EGroup Captain James Pelly-Fry Unique construction hallmark RAF bomber Brit ish used Ethiopia against Mussolini during early years WW II RC model design bit history come us men actually flew full-size plane action PART OF THE ROMANCE Scale aero modeling lies rescuing obscure forgot ten long-lost aircraft oblivion giving second life Searching details data necessary recreate old aircraft satisfying itself also adds another dimensionthe thrill huntto rewards pleasures acquiring expertise model builder Vickers Wellesley example just such long-forgotten discarded air craft long-range single-engine RAF bomber piloted World War II uncommonly efficient construction interesting history well worth know ing about brainchild Sir Barnes Wal lis Later war designed airships bouncing bomb destroyed huge dams Germany Wellesley flown successfully day night over Ethiopia against Mussolinis forces remarkable aircraft possessed ex ceptional load-carrying capabilityeven standard form could lift much its own weight 1938 three specially equipped Wellesleys flown nonstop over 48 hours Egypt Australiaa just-over-7 000-mile trip overturned world record distance held until Russia Fifty years ago 7000 unbroken miles fairly impressive achievement privileged command Wellesley squadrons having served second-in-command another squadron earlier war found air craft well exceeded expectations also piloted Douglas A20 Bob Wis cher has successfully built test flown Flying Scale model Wellesley comes second scaled-down version 52 Model Aviation Top extra wingspan lightweight construction enabled long-range RAF bomber lift much its own weight Above Its great thrill resurrect old de sign its particularly exciting bring plane back since no full-size version remains one-time military prototype person ally flew aviator As full-size aircraft both Douglas Wellesley did su perlative job very different wartime cir cumstances both have equal place sentiments salient characteristics Welles ley its very large wingspan 74 ft prototype good news model version use unique form air frame construction Barnes Wallis called geodetic consisting essentially double-spiral structure fuselage what might called basket weave wing stabilizer geodetic construc tion gave Wellesley exceptional light ness strength cardinal rule airplane design wing particular both extremely light very strong So far know single Wellesley specimen has recovered posterity left desert fate after Allied Forces moved Southern Europe Thus designing scaled-down version worthy aircraft researchthe aforementioned huntwould have lim ited whatever drawings sketches photographs could obtain Beaumont Avi ation London specializes keep ing records aviation data old maga zines books etc supplied some valuable material fortuitous coincidence also helped Matchbox Model Company recently produced 12-in-span stick together Wellesley kit ex Construction Once sufficient data work has collected piv otal step Scale design decide upon suitable scale choose hardware determined rest followsprob lems Wellesley after doing some figures back old enve lope chose Mo-scaleas RAF Boston counterpart A20 way Id get big wing keep wing loading down reasonable figuresthe perennial aim often eludes Scale modeler wingspan would 90 hoped get weight down around eight pounds power plant Enya 40-4C fourstroke seemed promising Id successfully fitted pair A20 RAF Bos ton case also happened have engines spare good friend Bud Voss uncertainty con cerned whether Enya sufficient power get big Wellesley airborne June 1988 53 cellent material supplied cooperative manufacturer got started proj ect Top particular model version plane once flew 223rd RAF Squadron Wellesley set distance world record 7000 continuous miles 1938 Above author rendition bombers piloted actually serving squadron commander during World War II scaled down one-tenth actual size big model flying safely Enya proved equal task landing gear supposed tail-down retractable job decided stay proven productthe excellent Rom-Air type As Boston gives creditable service very high wing loading sometimes occasions dramatic arrivals touchdown seemed natural choice use known entity Fuselage Fairly conventional construction used geodetic inner framework omitted sake weight-watch ing leaving four longerons stringers prototype establish correct oval shape cross section practice fabric covering used aft pilots cockpit course number flats sufficient number stringers employed maintain gen eral oval shape critical eye fuselage made up two halves using datum line straight along center line between top bottom halves method gives good foundation construction Mosquito employed es sentially same procedure dif ference being Mossie fuselage joined up top-and-bottom rather like chocolate Easter egg A-in-thick three-ply bulkheads TO I MAKE 2 MAKE RU 3RINS MA TRIM MAPLE MOTOR M U SHAPE BRA1 SCALE VOKES CARB FROM BALSA RLOCKS EV RUDDER SEEN PROM REAR H VB I/5 BALSA POST3 3/16 BALSA PIN 7 RUDDER F AME / I/I6 BALSA RI RINSEN LOCATION S TRIMTAB--H MUSC WRE TAILWHEE7 BRACEjXB BALSANOTSH BLOCKASEE TE XDETA LS S DA TALWHEEL 0IS345 constructed drawings appro priately slotted take north-south east-west longerons intermediate stringers completed cut across horizontal centerline using razor saw removes minimum timber useful number bulkhead go situated behind pi lots canopy has duplicated provide endpiece removal hatch reason make sure lower halves twin bulkhead glued gether top halves just lightly spot glued subsequent separa tion double lower bulkhead gives added strength rear spar wing passes through fuselage later Lay out full-size drawing top view fuselage building board steam shape first pair 4 x A-in spruce obechi sticks lie flat joined together 54 Model Aviation Using run-up table makes easier get everything assembled perform engine adjustments See text details making polystyrene external bomb containers Operating flaps slow big model down floating touchdowns add realism real beauty model lies just below its skin unique geodetic construction used designer Barnes Wallis give Wellesley lots strength lots weight Full-Size Plans Available. See Page 164 F WOOS .ASS B EPOXY ENGINE ORBOMB BOX IS MADE FROM FOAM BLOCK AND COVERED WITH FIBERGLASS EPOXYBOOS SUPPORT FRONT VIEW SCRAP WOOD SUPPORTS SAND TO AIRFOIL SHAPE SIDE VIEW USELAGE TOP VIEW NOTE FORMERS B THRO H ARE I/B PLYWOODTRIM AND NOTCH PER B F FIN CROSS IONREAR CLEAR PLASTIC CANOPY ENS SERB lIlY RUCTION FUSELAGE SIDE VIEW BOMB BOX y C I/4 PLY 1/B PLY -FORMERS-___ ---____________________ --I/G SO BALSA STRINGERS SPAR LINE I/4 I/lB BALSA LONG ERONS FIBERGLASS TOWNEND RING -x I/RPLYWOOO1/4 PLYWOOD / II LS MAPLE MOTOR MOUNTS K I FORWARD CLEAR PLASTIC CANOPY CLEARFUEL TANK PLASTICREMOVABLEVENTS WINDOWHATCH LINE C/771 E5OZFUELTANK SI/lB PLY FLAPS FLAP HORN ELEVATOR SERVO-i 2-I/ST INCIDENCE CS Y\ELAEJ--LSRyg I/32 PLY WHEEL COVERS WHEELS RCVR 5rNI II - ERY lID 3/B MAPLE MOTOR MOUNTS CLEAR PLASTIC WINDOW FIBERGLASS TOWNEND /1 oif i$ 40- 4 CYCLE ENGINE --c- I-S/B DIA SPINNER SHEET OF 2 MODEL AVIATION VICKERS WELLESLEY DESIGNED BY GRP CAPT JAMES PELLY FRY TRACING BY JOE DEMARCO RESERVED counterparts form completed longe rons Having pinned two sticks down securelyI pin either side through themtake top half-bulkhead hoop sequence glue its correct location Its best time hoop pretty unstable its small base halfbulkhead hoops glued position quick results used epoxy sup ported hoop anything handyso long hoop remained dead upright dur ing glue setting front bulkhead dou ble thickness ply strength Steam bend shape top longe rons again 1/4 x % Slot glue half-bulkhead hoops Slot glue %-in-sq balsa string ers fitting alternately avoid distor tion top half fuselage semicomplete sturdy enough handle re move building board An Enya 40 four-stroke provided plenty power model Note wire remote glow plug connector fuselage beams may look flimsy theyre plenty strong enough June 1988 55 drawing Place somewhere level weights bottom longerons pre serve true shape begin over again construction lower half fuselage constructing fuselage half keep mind its unnecessary stringers go way back theres much room anyway thin back end So its good idea shorten other suit eye case remove stringers last bay tail unit located Another im portant reminder Take great care second half fuselage duplicates first exactly possible particu larly true midpoint longerons must either glued fitted together inspection access hatch location Its impor tant take pains craftsmanship early stage project After checking two identical fu selage halves join together exactly apply glue along edgeswith important exception front half longe rons will glued just fitted gether what call touching fit around inspection hatch area youll separating hatch razor blade later Bring faces both glued fitted together secure along entire length springloaded office-type bulldog clipsvery handy grip firmly can fitted hand now have nicely shaped fairly stiff fuselage frame oval bulkheads have rigidity will ever needthe nylon covering add later will support moreand fuse lage length joined-up parts become good strong 14 x A-in-sq section forming master longerons along centerline Before setting aside masterpiece Im sure family friends will agree remove stringers last end bay tail unit will located will later replaced super-thin three-ply screwed place form ac cess hatches main hatch up front quick-remove can temporarily left spot glued place allow get used its new shape Empennage greatest need back end maximum lightness combined adequate strength flight ground handling fraction superfluous weight tail model roughly equivalent putting four times much nose Building light tail order exact weight penalty cannot stressed too strongly too often par ticularly Scale modeling basic layout prescribed external shape prototype builder finds after installing essential items like en gine fuel tank servo radio battery etc well up front still needs add much-dreaded ballast correct balance point Some Scale models need much two pounds lead squeezed nose offset tail weight thats terrible handicap Models short noses present biggest problems thus tend avoided Because requirement lightness materials stabilizer elevators fin rudder chosen great care kept judicious minimum wood primarily soft balsa plus small amount hard balsa little / super birchwood ply made Finlandthe latter strengthen both sides stabilizer main spar rudder post thin ply glued side separately keeping little oversize sanding down shape spars taper slighfly out tips theyre made up check twist during construction theyre weighted down during gluing allowed dry out well will remain straight true 2-in aluminum tube used connect elevators attach homemade control horns As fuselage make empen nage over drawings ensure accurate shape subtle curves give model its realism stabilizer distin guished its lattice-work geodetics elevators slightly off-center i/B PLY R-5~21/8 PLY EL I/B 1/5 BALSA 8-7 SMALL HINGES TO SUIT F SOFT BALSA BLOCK WING liPS HI LI STABILIZ GE IC LINES I/E S/lB BALSA-KEEP IT LIGHT-GEE TEST DETAILS BUILD FRAME FROM LAMINATES BALSA CROSSSECTION ALSALES R Left The air tank Rom-Air retracts servo operates valve inspection covers held place six self-tapping screws blisters necessary accommodate wheels Right Small inner covers wheel wells closed wheel itself upon retraction gear down weighted arms small doors keep open Plastic straps cover hole gear up 56 Model Aviation Full-Size Plans Available. See Page 164 R-6I/B PLYY SPAR IS /41/16 SPRUCE I/B PLYBOMB BOX LOCATIONWITH BALSA VERY SRAIN WEBS HORN MOUNTSEE TEST LEFT WINGWINS JOINT -LINE PLYAILERONR-I HORNB-S N-SILERO N-B-SERV -R -N C --ROM-AI RETRAC/ CB-BASEPLA/ IN / APBEPUBOS P0AERV L SR ROD AILERONS ARE BUILT UP SPARREARWITH BMSA RIBS SEE TEXT PLYSPAR DIHEDRAL 5-1/5 2FLAPS ARE I/IN PLY UNDER WINS5/16 PLY PLY RIBSEOOETIC LINES I/IN SEEP BY S/B WIDE BALSA SECTION ROOT CHORDSEE TEXT FOR CONSTRUCTIONR-2% SIB BALSA LE TAPEREDI/B PLY -RIGHT WING B-S AlONB-SR R ERV -A- SERVO FLAP AILERON HORN VICKERS WELLESLEY PLY HORN I161JNT DESIGNED BY GRP CAPT JAMES PELLY FRY BALSA YE STOCK0IS54BBTRACING BY JOE DEMARCO IIIII IGHTS ft SHEET 2 OF 2 MODEL AVIATION horns avoid contact rudder fin-rudder assembly completed have full travel latter influenced conventional Use small plastic necessarily covered stage now shape inboard part eleva hinges slipped pre-cut slots cor- set up fuselage Make provision tors sweep stabilizer rect midline points frame glued foot spar rudder post spar practice Wellesley does minimum epoxy Check secur- spar standing glued onto small need much application rudder normal ity pulling gently hinge after block rudder course has move flight since ailerons epoxy has cured may next freely double arms horns must work model ailerons coupled day trick fitting stabilizer eleva tors fuselage cut away lead ing edge spar sufficiently enable maneuvered place Once thats done stand fuselage its nose floor steady glue main spar onto back rearmost bulkhead midpoint Theres very little room area work carefully accurately mak ing sure stabilizer dead square fuselage upright Once epoxy has set can build up broken lead ing edge short piece hard balsa glued bulkhead along side using filler piece necessary June 1988 57 Detail geodetic wing construction locations aileron flap servos Left Band-sawing soup can half soldering tin across flat bottom resulted nice looking custom fuel tank Right molding tools beds used make canopies see text details right aerodynamically clean Townend cowl rudder least time being may change separate controls later Once again rehearse final assembly glu ing making sure everything true accurate beforehand Replace stringers cut away earlier last end bay fuselage four shaped pieces / ply will provide access moving parts tail elevator rudder steerable tail wheel builder prefers stringers can left out first place since chance fuselage twist slight four small very light panels secured bulk heads very small self-tap screws spare weight put just enough no little visual embellish ment adds almost nothing weight quarter-section ping pong ball can fitted glued edge top half rear bulkhead elevator rudder controls closed-loop type Closed-loop systems work fine save weight used very lightweight fishing trace wire nylon cov ered should no 10-lb break ing strength assembling servo coupling up wires use miniature fishing tackle swivels servo end fish ing gear ferrules trap wire coupling up nip two wire cutters advantage swivels can ad just correct tension removing clevis worse twisting wire Allow enough slack wires can move sideways about midpoint end-to-end approximately ly tight wires bad servos steerable tail wheel 2 A-in dia light can find mounted made-up fork piano wireabout 16-gauge just stiff enough job Bind ends thin wire solder lightly slide piece aluminum tube glue epoxy Trim wire ends unit fits another tubeyou want nice sliding fitwhich epoxied built-up unit fuselage use balsa pieces give rigidity Test smooth movement Make up own crank horn carefully epoxy collar type used landing wheels Locked grub screw collar traps inner tube top projects above bear ing its horn connects arm rudder horn now have good steer able tail wheel adjustable cor rect tracking taking off taxiing also removable neces sary book neat taxiing straight down-the-dotted-line takeoffs add re alism model flight point backtrack front end fuselage few major jobs have done before proceeding other work make access cover removable b cut away part fu selage form air-gunner/radio mans position make pilots gunners canopies c cut away part fuse lage underside accommodate wing root double spars make hatch access cover remov able begin slipping razor blade tween centerline longerons break spot gluing will free cover nicely help retain its shape after removing cover fit small strut across back hatch fit front would prevent putting taking off cover cover off glue place double-thickness front bulkhead gluing bottom half hatch cover now has no forward movement Prevent side ways movement fitting little feet hatch cover slip inside longerons Make small adjustments hatch fits snugly position secure nylon bolts small platforms glued bulk heads inside fuselage can take cap tive nuts Recessed bolts help appearances Making pilots gunners canopies first think about awhile Since chance finding anything ready-made approximates right size shape nil have no op tion make yourself method chose heat-mold oven using molding tool finding way position clear acetate sheet securely newly found expertise area welcome Choose piece balsa big enough task Using drawings perhaps photographs carve sand pretend can opy will sit place fuselage inside part sits nicely either before after cutting away unwanted part fuselage begin carve shape canopy itself Balsa easy work type job since lot so-called carving reality coarse sanding rather actual shaping carvers tool solid balsa canopy appears just right eye make hole underpart crea tion accept handle choice used 4-in length -in doweling sure epoxy handle well has work canopy-and-handle unit serves molding tool Give good hard var nish Next make wood bed little bigger plan size tool sup ported feet high enough tool can go through matching hole mat tress leaving bit space say around can move tool out nicely take piece thin acetate sheet pin way around close hole push pins work fine Now comes fun part things 58 Model Aviation seems shame hide structural work like underneath covering Scale model full-size bombers have never known fOr having see-through wings Left Inside structure details cockpit hatch Right one-piece removable cockpit hatch give total access inner workings quiet kitchen mama out shop ping turn electric oven maxi mum heat oven has preheated high will go put bed metal tray oven leaving main door open inner glass door shut Watch what happens closely After about minute will see acetate beginning ripple meaning has softened heat Before collapses take out bed its tray grab tool pronto push firmly hole bed acetate has softened correctly tool will force accept its shape have lucky tool will now below mat tress level will soon cool its cool enough handle gently wiggle tool back forth until sepa rates acetate now has just shape intended Remove bed trim off frilly part skirt its set fitted fuselage Dont expect good results first time tempt heat-mold procedure its bit knack get right may need try before youre successful pilots canopy after final trimming nice fit can edge glued place Use short lengths masking tape hold position during setting gunners can opy prototype quite cleverly hinged its opened back half becomes windshield front part disappears inside fuselage Wellesley gunners kept canopy open al time being very little air turbulence generally warm air over Af rica Making models canopy swivel though would have complicated also impractical standpoint canopy will stiff using thin ac etate sheet permanently closed want realism swivel can opy no harm trying make gunners canopy permanently closed dont forget make up lifelike Lewis gun mount cut slot fixed metal com partment prototype rear canopy stowage gun task cutting away part fuse lage underside accommodate wing spars may done now left until after main part wing has con structed modelers discretion latter sequence may better either way method same After marking unwanted areasthe main spar thin rear sparcut out fretsaw knife building up ends big cutaway ply shape upper line cutout must coincide root wing ribs idea being fu selage fits onto wing other way around low-slung wing Vickers Wellesley Mk 1 Single-engined RAF tight bomber Model scale 1/10th based L2714 wartime identity letters AO-A No 223 Squadron RAE Dimensions Wingspan895 Wing area6298 sq ft 907 sq Wing sectionRAE32 Root chord15in Tip chord65in mci balsa tip Aspect ratio88 Fuselage length47in Wing dihedral21/20 Wing washoutouters30 Engine Enya 40-4C four-stroke 65cc 1/2 hp PropellerTornado reinforced nylon 121/2 x 5 Maximum rpm ground run 8500 Weights Fuselage tail unit motor fuel tank 43 oz Wing complete Rom-Air gear z Radio8 servos 6 channels 18 oz Bomb containers 4 oz FuelS fluid oz 4 oz Total 127 oz 7 lb 15 oz Nominal 2 oz ballast added damp down elevator response necessary Wing loading 8 lb wt 0 ozIsq ft Control throwsat trailing edge Elevator way Rudder 1 way Ailerons % up % down Flaps 11/2 full down approx 400 makes sense have supporting fuse lage times Dont dismayed small amount fuselage material re mains after the big cutout accommo dating wing has made hatch removed isnt cause con cern Suitably strengthened balsa planks favorite /64 ply side its frame fuselage tougher appearsready perils flying life crashes Once three jobs done rest fuselage construction basically con ventional spiced few specific adapta tions Two beechwood engine bearers 5 long in cross section slotted bulkheads also pro vide platform special fuel tank slightly offset make room engine servoa snug fit space available Its remarkable much design work has done certain areas ac commodate essential items Once engine bearers have fitted supplementary platforms radio gear ser vos etc can provided suit individual preference however recommend locate everything along lines Wellesley way youll least know everything works together logical fashion have good access parts space behind Enya 40-4C engine front bulkhead filled aluminum sheet cowl top half shaped paper pattern made ear lier screwed thick front bulkhead bottom half thin ply glued place pilots cockpit also part fuse lage construction After cutting out small cockpit area hatch cover make wooden replica windshield framework will probably have noticed order simulate solid front sec tion fuselage going back far cockpit balsa sticks have sandwiched between longerons stringers solid structure nicely sanded down sists making neat job cockpit sur round windshield frame made match drawing applies equally canopy minor trimming can June 1988 59 opy will needed before final test fit gluing Make certain however thing position before glue since af terwards youll have no further access cockpit except inside hatch removed simulated glass windshield panels made clear Plexiglass cut thick enough look good little care shaping panel before gluing will give realistic ap pearance Dont forget human eye tends look things some kind prior ity case Scale model its cockpit area attracts Wing Wellesley somewhat other airplane Im familiar constructing wing key crucial step model priority consideration get near geo detic construction prototype possi ble Almost important decision use well-proven system removable outer wings Boston radio setup dictated fact fuselage would sit wing just four bolts keep decided mount aileron flap servos together Rom-Air unit wing accommodating other components within fuselage makes preflight assemblyand post-flight disassemblyas simple foolproof possible As prototype starting point wing construction Y-shaped main spar design gives great strength its needed also accommodates landing gear nicely spar fashioned primarily top bottom sticks 14 x /16 spruce supplemented vertical grain balsa webs beefed up ply facing near wing roots before assembly spars very sturdy initial stages construction wing structure consists four master ply ribs distributed along inner wing assem bly shown drawings cut trimmed glued position Cut small narrow vertical slots outboard master ribs accommodating wing joiners refer plans Port star board wings constructed separately spruce spars projecting two inches beyond wing root ribs form struc ture center section Place wing skeleton wing plan drawing add balsa shaped leading edge spar rear spar latter built up -in strip balsa medium hard / ply facings Glue face separately ply being little oversize sand down afterwards will get light stiff spar trouble three spars glued integrally four master ribs before begin ning geodetic construction phase install balsa platforms flap aileron servos according drawing loca tion seems work out fine given de sign factors involved access panels very thin ply can secured very small self-tap screws suitably posi tioned small hardwood blocks no need quick access field Youre now ready turn two halfwing skeletons geodetic ones Using geodetic lines drawing roughly correspond prototype pre pare large quantity balsa sticks /16 soft sheet balsa about % wide Work ing along panel upper part frame cut fit sticks edge up herringbone pattern Run same pattern opposite direction cutting fitting sticks slot original ones creates arrangement diamond shapes squares somewhat resembling egg-crate An important point remember sticks positioned little higher wing contour Next make sanding stick Cover straight batten about 1 x 114 just little longer span half-wing sandpapercoarse side fine other halfwing lap begin sanding evenly across span structure working grain balsa sticks wherever possible Soon wing contours begin show have sanded down almost point touching master ribs use fine sandpaper finish off now have nicely shaped accurate tapered wing geodetic construction wing has strength spare could fact build acceptably strong using less material wing gener ously built still light needs hold back RAF 32 airfoil dupli cates the prototype par ticular airfoil must can substi tute nice-looking NACA biconvex version thats minimum two inches deep root chord Once first wing half looking good topside turn over create same airy basket weave contours underside Repeat process both sides other wing half routine beginning stale least know end product justifies means Wellesleys geodetic wing singularly twist-free light Now youre ready join wing pan els together first step make jigs support wings positioned drawings jigs must provide secure base give necessary 2 0 dihe dral prototype Equally important wing half must have precisely identical rigging angles fore aft pays work carefully accurately process wings carefully positioned over drawing ballasted necessary keep steady jigs angles correct whole business symmetri cal connect spruce spars project fuselage bay spruce cut shape like epoxy job its quick drying strong main spar connected repeat rear spar shaped front balsa spars have joined since main spar its doubled Y configuration provides strength enough Remove inner wing jigs beef up spar assembly vertical grain balsa join has taken place Check eye looks good Add three-ply faces spar make extremely serviceable cen ter section job have specific use well provide location brack ets accept nylon bolts attach fuselage wing Trial fit fuselage main part wing making usual adjustments alterations get right wing root ribs should bed nicely cutaway part fuselage wing must dead square fuselage centerline Continued page 138 60 Model Aviation Left The left wings outer panel Du-Sro quarter-turn latches secure inspection hatch twin belicrank elevator con nected servo cables Note lower edge rudder prolects forward way aft end tail wheel mount RC Helicopters/Jolly Continued page 135 possible go flybarless rotor head Ive flying GMPs heads flybarless several years now have excellent re suits modifying following way center yoke bandsawed off top machined portion head head assembled normally except damp ening must tight possible Rang ers ran GMP blades cut rotor diameter 58 blade ballasted center-of-gravity-corrected weight 190 grams Set up way ships superb fly Because use no mixer headjust two links direct swashplateI must cut down collective cyclic throws can quite excessive try heads flybarless just make sure dampening tight throws reduced head gets normal pitch changes youll really like flying flybarless Also 190-gram blades autorotations dream fact night flying Rangers just set down ground Being cute hit throttle hold pulled up collective head has much inertia Helicopter lifted higher head settled slowly back ground thought sure would run out blade speed bend bird up honest soft touchdown achieved So finished three Rangers time shipped ahead Globe AZ film ing would take place arrived two days later uncrated beauties finding minimal damage flicted air freight kind winced found Out would flying elevation 4000 ft Believe nothing gets director excited watch ing flying bomb winding up wanting lift off loaded 13 lb Cobra/ Rangers flew excellentlyeven altitude Franidy after building three Helicopters shipping location span month flying anticlimactic director picked out rock face locked off two high-speed cam eras panned two hit spot first time Id used real explosives like potassium nitrate primer cord weird have machine strike wall see flash observe total disintegration fuselage mechanics falling ground As loaded up after destroying third ship thinking grateful could de pend various model companies provide quality equipment capable doing job safely Anyway see Midnight Run look small part model aviation played give believable explosion New GMP machine coming Gorham Model Products has just given permission nounce new aerobatic Helicopter Leg end have flown prototype can tell Legend quite capable dar ing acrobatic maneuvers GMP will showing ship Toledo made show saw public display first time Anyway Legend still cooperative ef fort between Gorham Hirobo lot Gorham Legend features flybar less rotor head toothed-belt tail rotor drive ex tremely light weight John says de mostly two new space age materials called aluminum steel As soon can get some pictures Ill give preview BCNU Wellesley/Pelly-Fry Continued page 60 thin three-ply flaps split type hinged rear spar three points side flaps lightly braced fore aft along inside span make rigid Small cutaways under wing accommodate will give snug fit flap bellcrank fitted coincide servo location Using servo flap merely conveni ent rather technical necessity Its easy harmonize two servos adjust ments devises method constructing wing out ers same main inner wing ailerons having recessed hinge Set up port starboard wings spe cially made jigs making provision three degrees washout cut sand soft balsa wing tips shape glue place Finish covering outers nylon Before constructing ailerons provide access aileron bellcranks using Du Bro quarter-turn latches As shown drawing aileron consists basically number balsa ribs half-round lead ing edges aluminum tube spar located fat point rib section trailing FOAM WING CORES muuumuu.uuuuuumummu.uuuuuuuuuuu.uuummm U U I PRECISION MADE EXPANDED BEAD POLYSTYRENE REPLACEMENT 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Edition: Model Aviation - 1988/06
Page Numbers: 52, 53, 54, 55, 56, 57, 58, 59, 60, 138
EGroup Captain James Pelly-Fry Unique construction hallmark RAF bomber Brit ish used Ethiopia against Mussolini during early years WW II RC model design bit history come us men actually flew full-size plane action PART OF THE ROMANCE Scale aero modeling lies rescuing obscure forgot ten long-lost aircraft oblivion giving second life Searching details data necessary recreate old aircraft satisfying itself also adds another dimensionthe thrill huntto rewards pleasures acquiring expertise model builder Vickers Wellesley example just such long-forgotten discarded air craft long-range single-engine RAF bomber piloted World War II uncommonly efficient construction interesting history well worth know ing about brainchild Sir Barnes Wal lis Later war designed airships bouncing bomb destroyed huge dams Germany Wellesley flown successfully day night over Ethiopia against Mussolinis forces remarkable aircraft possessed ex ceptional load-carrying capabilityeven standard form could lift much its own weight 1938 three specially equipped Wellesleys flown nonstop over 48 hours Egypt Australiaa just-over-7 000-mile trip overturned world record distance held until Russia Fifty years ago 7000 unbroken miles fairly impressive achievement privileged command Wellesley squadrons having served second-in-command another squadron earlier war found air craft well exceeded expectations also piloted Douglas A20 Bob Wis cher has successfully built test flown Flying Scale model Wellesley comes second scaled-down version 52 Model Aviation Top extra wingspan lightweight construction enabled long-range RAF bomber lift much its own weight Above Its great thrill resurrect old de sign its particularly exciting bring plane back since no full-size version remains one-time military prototype person ally flew aviator As full-size aircraft both Douglas Wellesley did su perlative job very different wartime cir cumstances both have equal place sentiments salient characteristics Welles ley its very large wingspan 74 ft prototype good news model version use unique form air frame construction Barnes Wallis called geodetic consisting essentially double-spiral structure fuselage what might called basket weave wing stabilizer geodetic construc tion gave Wellesley exceptional light ness strength cardinal rule airplane design wing particular both extremely light very strong So far know single Wellesley specimen has recovered posterity left desert fate after Allied Forces moved Southern Europe Thus designing scaled-down version worthy aircraft researchthe aforementioned huntwould have lim ited whatever drawings sketches photographs could obtain Beaumont Avi ation London specializes keep ing records aviation data old maga zines books etc supplied some valuable material fortuitous coincidence also helped Matchbox Model Company recently produced 12-in-span stick together Wellesley kit ex Construction Once sufficient data work has collected piv otal step Scale design decide upon suitable scale choose hardware determined rest followsprob lems Wellesley after doing some figures back old enve lope chose Mo-scaleas RAF Boston counterpart A20 way Id get big wing keep wing loading down reasonable figuresthe perennial aim often eludes Scale modeler wingspan would 90 hoped get weight down around eight pounds power plant Enya 40-4C fourstroke seemed promising Id successfully fitted pair A20 RAF Bos ton case also happened have engines spare good friend Bud Voss uncertainty con cerned whether Enya sufficient power get big Wellesley airborne June 1988 53 cellent material supplied cooperative manufacturer got started proj ect Top particular model version plane once flew 223rd RAF Squadron Wellesley set distance world record 7000 continuous miles 1938 Above author rendition bombers piloted actually serving squadron commander during World War II scaled down one-tenth actual size big model flying safely Enya proved equal task landing gear supposed tail-down retractable job decided stay proven productthe excellent Rom-Air type As Boston gives creditable service very high wing loading sometimes occasions dramatic arrivals touchdown seemed natural choice use known entity Fuselage Fairly conventional construction used geodetic inner framework omitted sake weight-watch ing leaving four longerons stringers prototype establish correct oval shape cross section practice fabric covering used aft pilots cockpit course number flats sufficient number stringers employed maintain gen eral oval shape critical eye fuselage made up two halves using datum line straight along center line between top bottom halves method gives good foundation construction Mosquito employed es sentially same procedure dif ference being Mossie fuselage joined up top-and-bottom rather like chocolate Easter egg A-in-thick three-ply bulkheads TO I MAKE 2 MAKE RU 3RINS MA TRIM MAPLE MOTOR M U SHAPE BRA1 SCALE VOKES CARB FROM BALSA RLOCKS EV RUDDER SEEN PROM REAR H VB I/5 BALSA POST3 3/16 BALSA PIN 7 RUDDER F AME / I/I6 BALSA RI RINSEN LOCATION S TRIMTAB--H MUSC WRE TAILWHEE7 BRACEjXB BALSANOTSH BLOCKASEE TE XDETA LS S DA TALWHEEL 0IS345 constructed drawings appro priately slotted take north-south east-west longerons intermediate stringers completed cut across horizontal centerline using razor saw removes minimum timber useful number bulkhead go situated behind pi lots canopy has duplicated provide endpiece removal hatch reason make sure lower halves twin bulkhead glued gether top halves just lightly spot glued subsequent separa tion double lower bulkhead gives added strength rear spar wing passes through fuselage later Lay out full-size drawing top view fuselage building board steam shape first pair 4 x A-in spruce obechi sticks lie flat joined together 54 Model Aviation Using run-up table makes easier get everything assembled perform engine adjustments See text details making polystyrene external bomb containers Operating flaps slow big model down floating touchdowns add realism real beauty model lies just below its skin unique geodetic construction used designer Barnes Wallis give Wellesley lots strength lots weight Full-Size Plans Available. See Page 164 F WOOS .ASS B EPOXY ENGINE ORBOMB BOX IS MADE FROM FOAM BLOCK AND COVERED WITH FIBERGLASS EPOXYBOOS SUPPORT FRONT VIEW SCRAP WOOD SUPPORTS SAND TO AIRFOIL SHAPE SIDE VIEW USELAGE TOP VIEW NOTE FORMERS B THRO H ARE I/B PLYWOODTRIM AND NOTCH PER B F FIN CROSS IONREAR CLEAR PLASTIC CANOPY ENS SERB lIlY RUCTION FUSELAGE SIDE VIEW BOMB BOX y C I/4 PLY 1/B PLY -FORMERS-___ ---____________________ --I/G SO BALSA STRINGERS SPAR LINE I/4 I/lB BALSA LONG ERONS FIBERGLASS TOWNEND RING -x I/RPLYWOOO1/4 PLYWOOD / II LS MAPLE MOTOR MOUNTS K I FORWARD CLEAR PLASTIC CANOPY CLEARFUEL TANK PLASTICREMOVABLEVENTS WINDOWHATCH LINE C/771 E5OZFUELTANK SI/lB PLY FLAPS FLAP HORN ELEVATOR SERVO-i 2-I/ST INCIDENCE CS Y\ELAEJ--LSRyg I/32 PLY WHEEL COVERS WHEELS RCVR 5rNI II - ERY lID 3/B MAPLE MOTOR MOUNTS CLEAR PLASTIC WINDOW FIBERGLASS TOWNEND /1 oif i$ 40- 4 CYCLE ENGINE --c- I-S/B DIA SPINNER SHEET OF 2 MODEL AVIATION VICKERS WELLESLEY DESIGNED BY GRP CAPT JAMES PELLY FRY TRACING BY JOE DEMARCO RESERVED counterparts form completed longe rons Having pinned two sticks down securelyI pin either side through themtake top half-bulkhead hoop sequence glue its correct location Its best time hoop pretty unstable its small base halfbulkhead hoops glued position quick results used epoxy sup ported hoop anything handyso long hoop remained dead upright dur ing glue setting front bulkhead dou ble thickness ply strength Steam bend shape top longe rons again 1/4 x % Slot glue half-bulkhead hoops Slot glue %-in-sq balsa string ers fitting alternately avoid distor tion top half fuselage semicomplete sturdy enough handle re move building board An Enya 40 four-stroke provided plenty power model Note wire remote glow plug connector fuselage beams may look flimsy theyre plenty strong enough June 1988 55 drawing Place somewhere level weights bottom longerons pre serve true shape begin over again construction lower half fuselage constructing fuselage half keep mind its unnecessary stringers go way back theres much room anyway thin back end So its good idea shorten other suit eye case remove stringers last bay tail unit located Another im portant reminder Take great care second half fuselage duplicates first exactly possible particu larly true midpoint longerons must either glued fitted together inspection access hatch location Its impor tant take pains craftsmanship early stage project After checking two identical fu selage halves join together exactly apply glue along edgeswith important exception front half longe rons will glued just fitted gether what call touching fit around inspection hatch area youll separating hatch razor blade later Bring faces both glued fitted together secure along entire length springloaded office-type bulldog clipsvery handy grip firmly can fitted hand now have nicely shaped fairly stiff fuselage frame oval bulkheads have rigidity will ever needthe nylon covering add later will support moreand fuse lage length joined-up parts become good strong 14 x A-in-sq section forming master longerons along centerline Before setting aside masterpiece Im sure family friends will agree remove stringers last end bay tail unit will located will later replaced super-thin three-ply screwed place form ac cess hatches main hatch up front quick-remove can temporarily left spot glued place allow get used its new shape Empennage greatest need back end maximum lightness combined adequate strength flight ground handling fraction superfluous weight tail model roughly equivalent putting four times much nose Building light tail order exact weight penalty cannot stressed too strongly too often par ticularly Scale modeling basic layout prescribed external shape prototype builder finds after installing essential items like en gine fuel tank servo radio battery etc well up front still needs add much-dreaded ballast correct balance point Some Scale models need much two pounds lead squeezed nose offset tail weight thats terrible handicap Models short noses present biggest problems thus tend avoided Because requirement lightness materials stabilizer elevators fin rudder chosen great care kept judicious minimum wood primarily soft balsa plus small amount hard balsa little / super birchwood ply made Finlandthe latter strengthen both sides stabilizer main spar rudder post thin ply glued side separately keeping little oversize sanding down shape spars taper slighfly out tips theyre made up check twist during construction theyre weighted down during gluing allowed dry out well will remain straight true 2-in aluminum tube used connect elevators attach homemade control horns As fuselage make empen nage over drawings ensure accurate shape subtle curves give model its realism stabilizer distin guished its lattice-work geodetics elevators slightly off-center i/B PLY R-5~21/8 PLY EL I/B 1/5 BALSA 8-7 SMALL HINGES TO SUIT F SOFT BALSA BLOCK WING liPS HI LI STABILIZ GE IC LINES I/E S/lB BALSA-KEEP IT LIGHT-GEE TEST DETAILS BUILD FRAME FROM LAMINATES BALSA CROSSSECTION ALSALES R Left The air tank Rom-Air retracts servo operates valve inspection covers held place six self-tapping screws blisters necessary accommodate wheels Right Small inner covers wheel wells closed wheel itself upon retraction gear down weighted arms small doors keep open Plastic straps cover hole gear up 56 Model Aviation Full-Size Plans Available. See Page 164 R-6I/B PLYY SPAR IS /41/16 SPRUCE I/B PLYBOMB BOX LOCATIONWITH BALSA VERY SRAIN WEBS HORN MOUNTSEE TEST LEFT WINGWINS JOINT -LINE PLYAILERONR-I HORNB-S N-SILERO N-B-SERV -R -N C --ROM-AI RETRAC/ CB-BASEPLA/ IN / APBEPUBOS P0AERV L SR ROD AILERONS ARE BUILT UP SPARREARWITH BMSA RIBS SEE TEXT PLYSPAR DIHEDRAL 5-1/5 2FLAPS ARE I/IN PLY UNDER WINS5/16 PLY PLY RIBSEOOETIC LINES I/IN SEEP BY S/B WIDE BALSA SECTION ROOT CHORDSEE TEXT FOR CONSTRUCTIONR-2% SIB BALSA LE TAPEREDI/B PLY -RIGHT WING B-S AlONB-SR R ERV -A- SERVO FLAP AILERON HORN VICKERS WELLESLEY PLY HORN I161JNT DESIGNED BY GRP CAPT JAMES PELLY FRY BALSA YE STOCK0IS54BBTRACING BY JOE DEMARCO IIIII IGHTS ft SHEET 2 OF 2 MODEL AVIATION horns avoid contact rudder fin-rudder assembly completed have full travel latter influenced conventional Use small plastic necessarily covered stage now shape inboard part eleva hinges slipped pre-cut slots cor- set up fuselage Make provision tors sweep stabilizer rect midline points frame glued foot spar rudder post spar practice Wellesley does minimum epoxy Check secur- spar standing glued onto small need much application rudder normal ity pulling gently hinge after block rudder course has move flight since ailerons epoxy has cured may next freely double arms horns must work model ailerons coupled day trick fitting stabilizer eleva tors fuselage cut away lead ing edge spar sufficiently enable maneuvered place Once thats done stand fuselage its nose floor steady glue main spar onto back rearmost bulkhead midpoint Theres very little room area work carefully accurately mak ing sure stabilizer dead square fuselage upright Once epoxy has set can build up broken lead ing edge short piece hard balsa glued bulkhead along side using filler piece necessary June 1988 57 Detail geodetic wing construction locations aileron flap servos Left Band-sawing soup can half soldering tin across flat bottom resulted nice looking custom fuel tank Right molding tools beds used make canopies see text details right aerodynamically clean Townend cowl rudder least time being may change separate controls later Once again rehearse final assembly glu ing making sure everything true accurate beforehand Replace stringers cut away earlier last end bay fuselage four shaped pieces / ply will provide access moving parts tail elevator rudder steerable tail wheel builder prefers stringers can left out first place since chance fuselage twist slight four small very light panels secured bulk heads very small self-tap screws spare weight put just enough no little visual embellish ment adds almost nothing weight quarter-section ping pong ball can fitted glued edge top half rear bulkhead elevator rudder controls closed-loop type Closed-loop systems work fine save weight used very lightweight fishing trace wire nylon cov ered should no 10-lb break ing strength assembling servo coupling up wires use miniature fishing tackle swivels servo end fish ing gear ferrules trap wire coupling up nip two wire cutters advantage swivels can ad just correct tension removing clevis worse twisting wire Allow enough slack wires can move sideways about midpoint end-to-end approximately ly tight wires bad servos steerable tail wheel 2 A-in dia light can find mounted made-up fork piano wireabout 16-gauge just stiff enough job Bind ends thin wire solder lightly slide piece aluminum tube glue epoxy Trim wire ends unit fits another tubeyou want nice sliding fitwhich epoxied built-up unit fuselage use balsa pieces give rigidity Test smooth movement Make up own crank horn carefully epoxy collar type used landing wheels Locked grub screw collar traps inner tube top projects above bear ing its horn connects arm rudder horn now have good steer able tail wheel adjustable cor rect tracking taking off taxiing also removable neces sary book neat taxiing straight down-the-dotted-line takeoffs add re alism model flight point backtrack front end fuselage few major jobs have done before proceeding other work make access cover removable b cut away part fu selage form air-gunner/radio mans position make pilots gunners canopies c cut away part fuse lage underside accommodate wing root double spars make hatch access cover remov able begin slipping razor blade tween centerline longerons break spot gluing will free cover nicely help retain its shape after removing cover fit small strut across back hatch fit front would prevent putting taking off cover cover off glue place double-thickness front bulkhead gluing bottom half hatch cover now has no forward movement Prevent side ways movement fitting little feet hatch cover slip inside longerons Make small adjustments hatch fits snugly position secure nylon bolts small platforms glued bulk heads inside fuselage can take cap tive nuts Recessed bolts help appearances Making pilots gunners canopies first think about awhile Since chance finding anything ready-made approximates right size shape nil have no op tion make yourself method chose heat-mold oven using molding tool finding way position clear acetate sheet securely newly found expertise area welcome Choose piece balsa big enough task Using drawings perhaps photographs carve sand pretend can opy will sit place fuselage inside part sits nicely either before after cutting away unwanted part fuselage begin carve shape canopy itself Balsa easy work type job since lot so-called carving reality coarse sanding rather actual shaping carvers tool solid balsa canopy appears just right eye make hole underpart crea tion accept handle choice used 4-in length -in doweling sure epoxy handle well has work canopy-and-handle unit serves molding tool Give good hard var nish Next make wood bed little bigger plan size tool sup ported feet high enough tool can go through matching hole mat tress leaving bit space say around can move tool out nicely take piece thin acetate sheet pin way around close hole push pins work fine Now comes fun part things 58 Model Aviation seems shame hide structural work like underneath covering Scale model full-size bombers have never known fOr having see-through wings Left Inside structure details cockpit hatch Right one-piece removable cockpit hatch give total access inner workings quiet kitchen mama out shop ping turn electric oven maxi mum heat oven has preheated high will go put bed metal tray oven leaving main door open inner glass door shut Watch what happens closely After about minute will see acetate beginning ripple meaning has softened heat Before collapses take out bed its tray grab tool pronto push firmly hole bed acetate has softened correctly tool will force accept its shape have lucky tool will now below mat tress level will soon cool its cool enough handle gently wiggle tool back forth until sepa rates acetate now has just shape intended Remove bed trim off frilly part skirt its set fitted fuselage Dont expect good results first time tempt heat-mold procedure its bit knack get right may need try before youre successful pilots canopy after final trimming nice fit can edge glued place Use short lengths masking tape hold position during setting gunners can opy prototype quite cleverly hinged its opened back half becomes windshield front part disappears inside fuselage Wellesley gunners kept canopy open al time being very little air turbulence generally warm air over Af rica Making models canopy swivel though would have complicated also impractical standpoint canopy will stiff using thin ac etate sheet permanently closed want realism swivel can opy no harm trying make gunners canopy permanently closed dont forget make up lifelike Lewis gun mount cut slot fixed metal com partment prototype rear canopy stowage gun task cutting away part fuse lage underside accommodate wing spars may done now left until after main part wing has con structed modelers discretion latter sequence may better either way method same After marking unwanted areasthe main spar thin rear sparcut out fretsaw knife building up ends big cutaway ply shape upper line cutout must coincide root wing ribs idea being fu selage fits onto wing other way around low-slung wing Vickers Wellesley Mk 1 Single-engined RAF tight bomber Model scale 1/10th based L2714 wartime identity letters AO-A No 223 Squadron RAE Dimensions Wingspan895 Wing area6298 sq ft 907 sq Wing sectionRAE32 Root chord15in Tip chord65in mci balsa tip Aspect ratio88 Fuselage length47in Wing dihedral21/20 Wing washoutouters30 Engine Enya 40-4C four-stroke 65cc 1/2 hp PropellerTornado reinforced nylon 121/2 x 5 Maximum rpm ground run 8500 Weights Fuselage tail unit motor fuel tank 43 oz Wing complete Rom-Air gear z Radio8 servos 6 channels 18 oz Bomb containers 4 oz FuelS fluid oz 4 oz Total 127 oz 7 lb 15 oz Nominal 2 oz ballast added damp down elevator response necessary Wing loading 8 lb wt 0 ozIsq ft Control throwsat trailing edge Elevator way Rudder 1 way Ailerons % up % down Flaps 11/2 full down approx 400 makes sense have supporting fuse lage times Dont dismayed small amount fuselage material re mains after the big cutout accommo dating wing has made hatch removed isnt cause con cern Suitably strengthened balsa planks favorite /64 ply side its frame fuselage tougher appearsready perils flying life crashes Once three jobs done rest fuselage construction basically con ventional spiced few specific adapta tions Two beechwood engine bearers 5 long in cross section slotted bulkheads also pro vide platform special fuel tank slightly offset make room engine servoa snug fit space available Its remarkable much design work has done certain areas ac commodate essential items Once engine bearers have fitted supplementary platforms radio gear ser vos etc can provided suit individual preference however recommend locate everything along lines Wellesley way youll least know everything works together logical fashion have good access parts space behind Enya 40-4C engine front bulkhead filled aluminum sheet cowl top half shaped paper pattern made ear lier screwed thick front bulkhead bottom half thin ply glued place pilots cockpit also part fuse lage construction After cutting out small cockpit area hatch cover make wooden replica windshield framework will probably have noticed order simulate solid front sec tion fuselage going back far cockpit balsa sticks have sandwiched between longerons stringers solid structure nicely sanded down sists making neat job cockpit sur round windshield frame made match drawing applies equally canopy minor trimming can June 1988 59 opy will needed before final test fit gluing Make certain however thing position before glue since af terwards youll have no further access cockpit except inside hatch removed simulated glass windshield panels made clear Plexiglass cut thick enough look good little care shaping panel before gluing will give realistic ap pearance Dont forget human eye tends look things some kind prior ity case Scale model its cockpit area attracts Wing Wellesley somewhat other airplane Im familiar constructing wing key crucial step model priority consideration get near geo detic construction prototype possi ble Almost important decision use well-proven system removable outer wings Boston radio setup dictated fact fuselage would sit wing just four bolts keep decided mount aileron flap servos together Rom-Air unit wing accommodating other components within fuselage makes preflight assemblyand post-flight disassemblyas simple foolproof possible As prototype starting point wing construction Y-shaped main spar design gives great strength its needed also accommodates landing gear nicely spar fashioned primarily top bottom sticks 14 x /16 spruce supplemented vertical grain balsa webs beefed up ply facing near wing roots before assembly spars very sturdy initial stages construction wing structure consists four master ply ribs distributed along inner wing assem bly shown drawings cut trimmed glued position Cut small narrow vertical slots outboard master ribs accommodating wing joiners refer plans Port star board wings constructed separately spruce spars projecting two inches beyond wing root ribs form struc ture center section Place wing skeleton wing plan drawing add balsa shaped leading edge spar rear spar latter built up -in strip balsa medium hard / ply facings Glue face separately ply being little oversize sand down afterwards will get light stiff spar trouble three spars glued integrally four master ribs before begin ning geodetic construction phase install balsa platforms flap aileron servos according drawing loca tion seems work out fine given de sign factors involved access panels very thin ply can secured very small self-tap screws suitably posi tioned small hardwood blocks no need quick access field Youre now ready turn two halfwing skeletons geodetic ones Using geodetic lines drawing roughly correspond prototype pre pare large quantity balsa sticks /16 soft sheet balsa about % wide Work ing along panel upper part frame cut fit sticks edge up herringbone pattern Run same pattern opposite direction cutting fitting sticks slot original ones creates arrangement diamond shapes squares somewhat resembling egg-crate An important point remember sticks positioned little higher wing contour Next make sanding stick Cover straight batten about 1 x 114 just little longer span half-wing sandpapercoarse side fine other halfwing lap begin sanding evenly across span structure working grain balsa sticks wherever possible Soon wing contours begin show have sanded down almost point touching master ribs use fine sandpaper finish off now have nicely shaped accurate tapered wing geodetic construction wing has strength spare could fact build acceptably strong using less material wing gener ously built still light needs hold back RAF 32 airfoil dupli cates the prototype par ticular airfoil must can substi tute nice-looking NACA biconvex version thats minimum two inches deep root chord Once first wing half looking good topside turn over create same airy basket weave contours underside Repeat process both sides other wing half routine beginning stale least know end product justifies means Wellesleys geodetic wing singularly twist-free light Now youre ready join wing pan els together first step make jigs support wings positioned drawings jigs must provide secure base give necessary 2 0 dihe dral prototype Equally important wing half must have precisely identical rigging angles fore aft pays work carefully accurately process wings carefully positioned over drawing ballasted necessary keep steady jigs angles correct whole business symmetri cal connect spruce spars project fuselage bay spruce cut shape like epoxy job its quick drying strong main spar connected repeat rear spar shaped front balsa spars have joined since main spar its doubled Y configuration provides strength enough Remove inner wing jigs beef up spar assembly vertical grain balsa join has taken place Check eye looks good Add three-ply faces spar make extremely serviceable cen ter section job have specific use well provide location brack ets accept nylon bolts attach fuselage wing Trial fit fuselage main part wing making usual adjustments alterations get right wing root ribs should bed nicely cutaway part fuselage wing must dead square fuselage centerline Continued page 138 60 Model Aviation Left The left wings outer panel Du-Sro quarter-turn latches secure inspection hatch twin belicrank elevator con nected servo cables Note lower edge rudder prolects forward way aft end tail wheel mount RC Helicopters/Jolly Continued page 135 possible go flybarless rotor head Ive flying GMPs heads flybarless several years now have excellent re suits modifying following way center yoke bandsawed off top machined portion head head assembled normally except damp ening must tight possible Rang ers ran GMP blades cut rotor diameter 58 blade ballasted center-of-gravity-corrected weight 190 grams Set up way ships superb fly Because use no mixer headjust two links direct swashplateI must cut down collective cyclic throws can quite excessive try heads flybarless just make sure dampening tight throws reduced head gets normal pitch changes youll really like flying flybarless Also 190-gram blades autorotations dream fact night flying Rangers just set down ground Being cute hit throttle hold pulled up collective head has much inertia Helicopter lifted higher head settled slowly back ground thought sure would run out blade speed bend bird up honest soft touchdown achieved So finished three Rangers time shipped ahead Globe AZ film ing would take place arrived two days later uncrated beauties finding minimal damage flicted air freight kind winced found Out would flying elevation 4000 ft Believe nothing gets director excited watch ing flying bomb winding up wanting lift off loaded 13 lb Cobra/ Rangers flew excellentlyeven altitude Franidy after building three Helicopters shipping location span month flying anticlimactic director picked out rock face locked off two high-speed cam eras panned two hit spot first time Id used real explosives like potassium nitrate primer cord weird have machine strike wall see flash observe total disintegration fuselage mechanics falling ground As loaded up after destroying third ship thinking grateful could de pend various model companies provide quality equipment capable doing job safely Anyway see Midnight Run look small part model aviation played give believable explosion New GMP machine coming Gorham Model Products has just given permission nounce new aerobatic Helicopter Leg end have flown prototype can tell Legend quite capable dar ing acrobatic maneuvers GMP will showing ship Toledo made show saw public display first time Anyway Legend still cooperative ef fort between Gorham Hirobo lot Gorham Legend features flybar less rotor head toothed-belt tail rotor drive ex tremely light weight John says de mostly two new space age materials called aluminum steel As soon can get some pictures Ill give preview BCNU Wellesley/Pelly-Fry Continued page 60 thin three-ply flaps split type hinged rear spar three points side flaps lightly braced fore aft along inside span make rigid Small cutaways under wing accommodate will give snug fit flap bellcrank fitted coincide servo location Using servo flap merely conveni ent rather technical necessity Its easy harmonize two servos adjust ments devises method constructing wing out ers same main inner wing ailerons having recessed hinge Set up port starboard wings spe cially made jigs making provision three degrees washout cut sand soft balsa wing tips shape glue place Finish covering outers nylon Before constructing ailerons provide access aileron bellcranks using Du Bro quarter-turn latches As shown drawing aileron consists basically number balsa ribs half-round lead ing edges aluminum tube spar located fat point rib section trailing FOAM WING CORES muuumuu.uuuuuumummu.uuuuuuuuuuu.uuummm U U I PRECISION MADE EXPANDED BEAD POLYSTYRENE REPLACEMENT 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Edition: Model Aviation - 1988/06
Page Numbers: 52, 53, 54, 55, 56, 57, 58, 59, 60, 138
EGroup Captain James Pelly-Fry Unique construction hallmark RAF bomber Brit ish used Ethiopia against Mussolini during early years WW II RC model design bit history come us men actually flew full-size plane action PART OF THE ROMANCE Scale aero modeling lies rescuing obscure forgot ten long-lost aircraft oblivion giving second life Searching details data necessary recreate old aircraft satisfying itself also adds another dimensionthe thrill huntto rewards pleasures acquiring expertise model builder Vickers Wellesley example just such long-forgotten discarded air craft long-range single-engine RAF bomber piloted World War II uncommonly efficient construction interesting history well worth know ing about brainchild Sir Barnes Wal lis Later war designed airships bouncing bomb destroyed huge dams Germany Wellesley flown successfully day night over Ethiopia against Mussolinis forces remarkable aircraft possessed ex ceptional load-carrying capabilityeven standard form could lift much its own weight 1938 three specially equipped Wellesleys flown nonstop over 48 hours Egypt Australiaa just-over-7 000-mile trip overturned world record distance held until Russia Fifty years ago 7000 unbroken miles fairly impressive achievement privileged command Wellesley squadrons having served second-in-command another squadron earlier war found air craft well exceeded expectations also piloted Douglas A20 Bob Wis cher has successfully built test flown Flying Scale model Wellesley comes second scaled-down version 52 Model Aviation Top extra wingspan lightweight construction enabled long-range RAF bomber lift much its own weight Above Its great thrill resurrect old de sign its particularly exciting bring plane back since no full-size version remains one-time military prototype person ally flew aviator As full-size aircraft both Douglas Wellesley did su perlative job very different wartime cir cumstances both have equal place sentiments salient characteristics Welles ley its very large wingspan 74 ft prototype good news model version use unique form air frame construction Barnes Wallis called geodetic consisting essentially double-spiral structure fuselage what might called basket weave wing stabilizer geodetic construc tion gave Wellesley exceptional light ness strength cardinal rule airplane design wing particular both extremely light very strong So far know single Wellesley specimen has recovered posterity left desert fate after Allied Forces moved Southern Europe Thus designing scaled-down version worthy aircraft researchthe aforementioned huntwould have lim ited whatever drawings sketches photographs could obtain Beaumont Avi ation London specializes keep ing records aviation data old maga zines books etc supplied some valuable material fortuitous coincidence also helped Matchbox Model Company recently produced 12-in-span stick together Wellesley kit ex Construction Once sufficient data work has collected piv otal step Scale design decide upon suitable scale choose hardware determined rest followsprob lems Wellesley after doing some figures back old enve lope chose Mo-scaleas RAF Boston counterpart A20 way Id get big wing keep wing loading down reasonable figuresthe perennial aim often eludes Scale modeler wingspan would 90 hoped get weight down around eight pounds power plant Enya 40-4C fourstroke seemed promising Id successfully fitted pair A20 RAF Bos ton case also happened have engines spare good friend Bud Voss uncertainty con cerned whether Enya sufficient power get big Wellesley airborne June 1988 53 cellent material supplied cooperative manufacturer got started proj ect Top particular model version plane once flew 223rd RAF Squadron Wellesley set distance world record 7000 continuous miles 1938 Above author rendition bombers piloted actually serving squadron commander during World War II scaled down one-tenth actual size big model flying safely Enya proved equal task landing gear supposed tail-down retractable job decided stay proven productthe excellent Rom-Air type As Boston gives creditable service very high wing loading sometimes occasions dramatic arrivals touchdown seemed natural choice use known entity Fuselage Fairly conventional construction used geodetic inner framework omitted sake weight-watch ing leaving four longerons stringers prototype establish correct oval shape cross section practice fabric covering used aft pilots cockpit course number flats sufficient number stringers employed maintain gen eral oval shape critical eye fuselage made up two halves using datum line straight along center line between top bottom halves method gives good foundation construction Mosquito employed es sentially same procedure dif ference being Mossie fuselage joined up top-and-bottom rather like chocolate Easter egg A-in-thick three-ply bulkheads TO I MAKE 2 MAKE RU 3RINS MA TRIM MAPLE MOTOR M U SHAPE BRA1 SCALE VOKES CARB FROM BALSA RLOCKS EV RUDDER SEEN PROM REAR H VB I/5 BALSA POST3 3/16 BALSA PIN 7 RUDDER F AME / I/I6 BALSA RI RINSEN LOCATION S TRIMTAB--H MUSC WRE TAILWHEE7 BRACEjXB BALSANOTSH BLOCKASEE TE XDETA LS S DA TALWHEEL 0IS345 constructed drawings appro priately slotted take north-south east-west longerons intermediate stringers completed cut across horizontal centerline using razor saw removes minimum timber useful number bulkhead go situated behind pi lots canopy has duplicated provide endpiece removal hatch reason make sure lower halves twin bulkhead glued gether top halves just lightly spot glued subsequent separa tion double lower bulkhead gives added strength rear spar wing passes through fuselage later Lay out full-size drawing top view fuselage building board steam shape first pair 4 x A-in spruce obechi sticks lie flat joined together 54 Model Aviation Using run-up table makes easier get everything assembled perform engine adjustments See text details making polystyrene external bomb containers Operating flaps slow big model down floating touchdowns add realism real beauty model lies just below its skin unique geodetic construction used designer Barnes Wallis give Wellesley lots strength lots weight Full-Size Plans Available. See Page 164 F WOOS .ASS B EPOXY ENGINE ORBOMB BOX IS MADE FROM FOAM BLOCK AND COVERED WITH FIBERGLASS EPOXYBOOS SUPPORT FRONT VIEW SCRAP WOOD SUPPORTS SAND TO AIRFOIL SHAPE SIDE VIEW USELAGE TOP VIEW NOTE FORMERS B THRO H ARE I/B PLYWOODTRIM AND NOTCH PER B F FIN CROSS IONREAR CLEAR PLASTIC CANOPY ENS SERB lIlY RUCTION FUSELAGE SIDE VIEW BOMB BOX y C I/4 PLY 1/B PLY -FORMERS-___ ---____________________ --I/G SO BALSA STRINGERS SPAR LINE I/4 I/lB BALSA LONG ERONS FIBERGLASS TOWNEND RING -x I/RPLYWOOO1/4 PLYWOOD / II LS MAPLE MOTOR MOUNTS K I FORWARD CLEAR PLASTIC CANOPY CLEARFUEL TANK PLASTICREMOVABLEVENTS WINDOWHATCH LINE C/771 E5OZFUELTANK SI/lB PLY FLAPS FLAP HORN ELEVATOR SERVO-i 2-I/ST INCIDENCE CS Y\ELAEJ--LSRyg I/32 PLY WHEEL COVERS WHEELS RCVR 5rNI II - ERY lID 3/B MAPLE MOTOR MOUNTS CLEAR PLASTIC WINDOW FIBERGLASS TOWNEND /1 oif i$ 40- 4 CYCLE ENGINE --c- I-S/B DIA SPINNER SHEET OF 2 MODEL AVIATION VICKERS WELLESLEY DESIGNED BY GRP CAPT JAMES PELLY FRY TRACING BY JOE DEMARCO RESERVED counterparts form completed longe rons Having pinned two sticks down securelyI pin either side through themtake top half-bulkhead hoop sequence glue its correct location Its best time hoop pretty unstable its small base halfbulkhead hoops glued position quick results used epoxy sup ported hoop anything handyso long hoop remained dead upright dur ing glue setting front bulkhead dou ble thickness ply strength Steam bend shape top longe rons again 1/4 x % Slot glue half-bulkhead hoops Slot glue %-in-sq balsa string ers fitting alternately avoid distor tion top half fuselage semicomplete sturdy enough handle re move building board An Enya 40 four-stroke provided plenty power model Note wire remote glow plug connector fuselage beams may look flimsy theyre plenty strong enough June 1988 55 drawing Place somewhere level weights bottom longerons pre serve true shape begin over again construction lower half fuselage constructing fuselage half keep mind its unnecessary stringers go way back theres much room anyway thin back end So its good idea shorten other suit eye case remove stringers last bay tail unit located Another im portant reminder Take great care second half fuselage duplicates first exactly possible particu larly true midpoint longerons must either glued fitted together inspection access hatch location Its impor tant take pains craftsmanship early stage project After checking two identical fu selage halves join together exactly apply glue along edgeswith important exception front half longe rons will glued just fitted gether what call touching fit around inspection hatch area youll separating hatch razor blade later Bring faces both glued fitted together secure along entire length springloaded office-type bulldog clipsvery handy grip firmly can fitted hand now have nicely shaped fairly stiff fuselage frame oval bulkheads have rigidity will ever needthe nylon covering add later will support moreand fuse lage length joined-up parts become good strong 14 x A-in-sq section forming master longerons along centerline Before setting aside masterpiece Im sure family friends will agree remove stringers last end bay tail unit will located will later replaced super-thin three-ply screwed place form ac cess hatches main hatch up front quick-remove can temporarily left spot glued place allow get used its new shape Empennage greatest need back end maximum lightness combined adequate strength flight ground handling fraction superfluous weight tail model roughly equivalent putting four times much nose Building light tail order exact weight penalty cannot stressed too strongly too often par ticularly Scale modeling basic layout prescribed external shape prototype builder finds after installing essential items like en gine fuel tank servo radio battery etc well up front still needs add much-dreaded ballast correct balance point Some Scale models need much two pounds lead squeezed nose offset tail weight thats terrible handicap Models short noses present biggest problems thus tend avoided Because requirement lightness materials stabilizer elevators fin rudder chosen great care kept judicious minimum wood primarily soft balsa plus small amount hard balsa little / super birchwood ply made Finlandthe latter strengthen both sides stabilizer main spar rudder post thin ply glued side separately keeping little oversize sanding down shape spars taper slighfly out tips theyre made up check twist during construction theyre weighted down during gluing allowed dry out well will remain straight true 2-in aluminum tube used connect elevators attach homemade control horns As fuselage make empen nage over drawings ensure accurate shape subtle curves give model its realism stabilizer distin guished its lattice-work geodetics elevators slightly off-center i/B PLY R-5~21/8 PLY EL I/B 1/5 BALSA 8-7 SMALL HINGES TO SUIT F SOFT BALSA BLOCK WING liPS HI LI STABILIZ GE IC LINES I/E S/lB BALSA-KEEP IT LIGHT-GEE TEST DETAILS BUILD FRAME FROM LAMINATES BALSA CROSSSECTION ALSALES R Left The air tank Rom-Air retracts servo operates valve inspection covers held place six self-tapping screws blisters necessary accommodate wheels Right Small inner covers wheel wells closed wheel itself upon retraction gear down weighted arms small doors keep open Plastic straps cover hole gear up 56 Model Aviation Full-Size Plans Available. See Page 164 R-6I/B PLYY SPAR IS /41/16 SPRUCE I/B PLYBOMB BOX LOCATIONWITH BALSA VERY SRAIN WEBS HORN MOUNTSEE TEST LEFT WINGWINS JOINT -LINE PLYAILERONR-I HORNB-S N-SILERO N-B-SERV -R -N C --ROM-AI RETRAC/ CB-BASEPLA/ IN / APBEPUBOS P0AERV L SR ROD AILERONS ARE BUILT UP SPARREARWITH BMSA RIBS SEE TEXT PLYSPAR DIHEDRAL 5-1/5 2FLAPS ARE I/IN PLY UNDER WINS5/16 PLY PLY RIBSEOOETIC LINES I/IN SEEP BY S/B WIDE BALSA SECTION ROOT CHORDSEE TEXT FOR CONSTRUCTIONR-2% SIB BALSA LE TAPEREDI/B PLY -RIGHT WING B-S AlONB-SR R ERV -A- SERVO FLAP AILERON HORN VICKERS WELLESLEY PLY HORN I161JNT DESIGNED BY GRP CAPT JAMES PELLY FRY BALSA YE STOCK0IS54BBTRACING BY JOE DEMARCO IIIII IGHTS ft SHEET 2 OF 2 MODEL AVIATION horns avoid contact rudder fin-rudder assembly completed have full travel latter influenced conventional Use small plastic necessarily covered stage now shape inboard part eleva hinges slipped pre-cut slots cor- set up fuselage Make provision tors sweep stabilizer rect midline points frame glued foot spar rudder post spar practice Wellesley does minimum epoxy Check secur- spar standing glued onto small need much application rudder normal ity pulling gently hinge after block rudder course has move flight since ailerons epoxy has cured may next freely double arms horns must work model ailerons coupled day trick fitting stabilizer eleva tors fuselage cut away lead ing edge spar sufficiently enable maneuvered place Once thats done stand fuselage its nose floor steady glue main spar onto back rearmost bulkhead midpoint Theres very little room area work carefully accurately mak ing sure stabilizer dead square fuselage upright Once epoxy has set can build up broken lead ing edge short piece hard balsa glued bulkhead along side using filler piece necessary June 1988 57 Detail geodetic wing construction locations aileron flap servos Left Band-sawing soup can half soldering tin across flat bottom resulted nice looking custom fuel tank Right molding tools beds used make canopies see text details right aerodynamically clean Townend cowl rudder least time being may change separate controls later Once again rehearse final assembly glu ing making sure everything true accurate beforehand Replace stringers cut away earlier last end bay fuselage four shaped pieces / ply will provide access moving parts tail elevator rudder steerable tail wheel builder prefers stringers can left out first place since chance fuselage twist slight four small very light panels secured bulk heads very small self-tap screws spare weight put just enough no little visual embellish ment adds almost nothing weight quarter-section ping pong ball can fitted glued edge top half rear bulkhead elevator rudder controls closed-loop type Closed-loop systems work fine save weight used very lightweight fishing trace wire nylon cov ered should no 10-lb break ing strength assembling servo coupling up wires use miniature fishing tackle swivels servo end fish ing gear ferrules trap wire coupling up nip two wire cutters advantage swivels can ad just correct tension removing clevis worse twisting wire Allow enough slack wires can move sideways about midpoint end-to-end approximately ly tight wires bad servos steerable tail wheel 2 A-in dia light can find mounted made-up fork piano wireabout 16-gauge just stiff enough job Bind ends thin wire solder lightly slide piece aluminum tube glue epoxy Trim wire ends unit fits another tubeyou want nice sliding fitwhich epoxied built-up unit fuselage use balsa pieces give rigidity Test smooth movement Make up own crank horn carefully epoxy collar type used landing wheels Locked grub screw collar traps inner tube top projects above bear ing its horn connects arm rudder horn now have good steer able tail wheel adjustable cor rect tracking taking off taxiing also removable neces sary book neat taxiing straight down-the-dotted-line takeoffs add re alism model flight point backtrack front end fuselage few major jobs have done before proceeding other work make access cover removable b cut away part fu selage form air-gunner/radio mans position make pilots gunners canopies c cut away part fuse lage underside accommodate wing root double spars make hatch access cover remov able begin slipping razor blade tween centerline longerons break spot gluing will free cover nicely help retain its shape after removing cover fit small strut across back hatch fit front would prevent putting taking off cover cover off glue place double-thickness front bulkhead gluing bottom half hatch cover now has no forward movement Prevent side ways movement fitting little feet hatch cover slip inside longerons Make small adjustments hatch fits snugly position secure nylon bolts small platforms glued bulk heads inside fuselage can take cap tive nuts Recessed bolts help appearances Making pilots gunners canopies first think about awhile Since chance finding anything ready-made approximates right size shape nil have no op tion make yourself method chose heat-mold oven using molding tool finding way position clear acetate sheet securely newly found expertise area welcome Choose piece balsa big enough task Using drawings perhaps photographs carve sand pretend can opy will sit place fuselage inside part sits nicely either before after cutting away unwanted part fuselage begin carve shape canopy itself Balsa easy work type job since lot so-called carving reality coarse sanding rather actual shaping carvers tool solid balsa canopy appears just right eye make hole underpart crea tion accept handle choice used 4-in length -in doweling sure epoxy handle well has work canopy-and-handle unit serves molding tool Give good hard var nish Next make wood bed little bigger plan size tool sup ported feet high enough tool can go through matching hole mat tress leaving bit space say around can move tool out nicely take piece thin acetate sheet pin way around close hole push pins work fine Now comes fun part things 58 Model Aviation seems shame hide structural work like underneath covering Scale model full-size bombers have never known fOr having see-through wings Left Inside structure details cockpit hatch Right one-piece removable cockpit hatch give total access inner workings quiet kitchen mama out shop ping turn electric oven maxi mum heat oven has preheated high will go put bed metal tray oven leaving main door open inner glass door shut Watch what happens closely After about minute will see acetate beginning ripple meaning has softened heat Before collapses take out bed its tray grab tool pronto push firmly hole bed acetate has softened correctly tool will force accept its shape have lucky tool will now below mat tress level will soon cool its cool enough handle gently wiggle tool back forth until sepa rates acetate now has just shape intended Remove bed trim off frilly part skirt its set fitted fuselage Dont expect good results first time tempt heat-mold procedure its bit knack get right may need try before youre successful pilots canopy after final trimming nice fit can edge glued place Use short lengths masking tape hold position during setting gunners can opy prototype quite cleverly hinged its opened back half becomes windshield front part disappears inside fuselage Wellesley gunners kept canopy open al time being very little air turbulence generally warm air over Af rica Making models canopy swivel though would have complicated also impractical standpoint canopy will stiff using thin ac etate sheet permanently closed want realism swivel can opy no harm trying make gunners canopy permanently closed dont forget make up lifelike Lewis gun mount cut slot fixed metal com partment prototype rear canopy stowage gun task cutting away part fuse lage underside accommodate wing spars may done now left until after main part wing has con structed modelers discretion latter sequence may better either way method same After marking unwanted areasthe main spar thin rear sparcut out fretsaw knife building up ends big cutaway ply shape upper line cutout must coincide root wing ribs idea being fu selage fits onto wing other way around low-slung wing Vickers Wellesley Mk 1 Single-engined RAF tight bomber Model scale 1/10th based L2714 wartime identity letters AO-A No 223 Squadron RAE Dimensions Wingspan895 Wing area6298 sq ft 907 sq Wing sectionRAE32 Root chord15in Tip chord65in mci balsa tip Aspect ratio88 Fuselage length47in Wing dihedral21/20 Wing washoutouters30 Engine Enya 40-4C four-stroke 65cc 1/2 hp PropellerTornado reinforced nylon 121/2 x 5 Maximum rpm ground run 8500 Weights Fuselage tail unit motor fuel tank 43 oz Wing complete Rom-Air gear z Radio8 servos 6 channels 18 oz Bomb containers 4 oz FuelS fluid oz 4 oz Total 127 oz 7 lb 15 oz Nominal 2 oz ballast added damp down elevator response necessary Wing loading 8 lb wt 0 ozIsq ft Control throwsat trailing edge Elevator way Rudder 1 way Ailerons % up % down Flaps 11/2 full down approx 400 makes sense have supporting fuse lage times Dont dismayed small amount fuselage material re mains after the big cutout accommo dating wing has made hatch removed isnt cause con cern Suitably strengthened balsa planks favorite /64 ply side its frame fuselage tougher appearsready perils flying life crashes Once three jobs done rest fuselage construction basically con ventional spiced few specific adapta tions Two beechwood engine bearers 5 long in cross section slotted bulkheads also pro vide platform special fuel tank slightly offset make room engine servoa snug fit space available Its remarkable much design work has done certain areas ac commodate essential items Once engine bearers have fitted supplementary platforms radio gear ser vos etc can provided suit individual preference however recommend locate everything along lines Wellesley way youll least know everything works together logical fashion have good access parts space behind Enya 40-4C engine front bulkhead filled aluminum sheet cowl top half shaped paper pattern made ear lier screwed thick front bulkhead bottom half thin ply glued place pilots cockpit also part fuse lage construction After cutting out small cockpit area hatch cover make wooden replica windshield framework will probably have noticed order simulate solid front sec tion fuselage going back far cockpit balsa sticks have sandwiched between longerons stringers solid structure nicely sanded down sists making neat job cockpit sur round windshield frame made match drawing applies equally canopy minor trimming can June 1988 59 opy will needed before final test fit gluing Make certain however thing position before glue since af terwards youll have no further access cockpit except inside hatch removed simulated glass windshield panels made clear Plexiglass cut thick enough look good little care shaping panel before gluing will give realistic ap pearance Dont forget human eye tends look things some kind prior ity case Scale model its cockpit area attracts Wing Wellesley somewhat other airplane Im familiar constructing wing key crucial step model priority consideration get near geo detic construction prototype possi ble Almost important decision use well-proven system removable outer wings Boston radio setup dictated fact fuselage would sit wing just four bolts keep decided mount aileron flap servos together Rom-Air unit wing accommodating other components within fuselage makes preflight assemblyand post-flight disassemblyas simple foolproof possible As prototype starting point wing construction Y-shaped main spar design gives great strength its needed also accommodates landing gear nicely spar fashioned primarily top bottom sticks 14 x /16 spruce supplemented vertical grain balsa webs beefed up ply facing near wing roots before assembly spars very sturdy initial stages construction wing structure consists four master ply ribs distributed along inner wing assem bly shown drawings cut trimmed glued position Cut small narrow vertical slots outboard master ribs accommodating wing joiners refer plans Port star board wings constructed separately spruce spars projecting two inches beyond wing root ribs form struc ture center section Place wing skeleton wing plan drawing add balsa shaped leading edge spar rear spar latter built up -in strip balsa medium hard / ply facings Glue face separately ply being little oversize sand down afterwards will get light stiff spar trouble three spars glued integrally four master ribs before begin ning geodetic construction phase install balsa platforms flap aileron servos according drawing loca tion seems work out fine given de sign factors involved access panels very thin ply can secured very small self-tap screws suitably posi tioned small hardwood blocks no need quick access field Youre now ready turn two halfwing skeletons geodetic ones Using geodetic lines drawing roughly correspond prototype pre pare large quantity balsa sticks /16 soft sheet balsa about % wide Work ing along panel upper part frame cut fit sticks edge up herringbone pattern Run same pattern opposite direction cutting fitting sticks slot original ones creates arrangement diamond shapes squares somewhat resembling egg-crate An important point remember sticks positioned little higher wing contour Next make sanding stick Cover straight batten about 1 x 114 just little longer span half-wing sandpapercoarse side fine other halfwing lap begin sanding evenly across span structure working grain balsa sticks wherever possible Soon wing contours begin show have sanded down almost point touching master ribs use fine sandpaper finish off now have nicely shaped accurate tapered wing geodetic construction wing has strength spare could fact build acceptably strong using less material wing gener ously built still light needs hold back RAF 32 airfoil dupli cates the prototype par ticular airfoil must can substi tute nice-looking NACA biconvex version thats minimum two inches deep root chord Once first wing half looking good topside turn over create same airy basket weave contours underside Repeat process both sides other wing half routine beginning stale least know end product justifies means Wellesleys geodetic wing singularly twist-free light Now youre ready join wing pan els together first step make jigs support wings positioned drawings jigs must provide secure base give necessary 2 0 dihe dral prototype Equally important wing half must have precisely identical rigging angles fore aft pays work carefully accurately process wings carefully positioned over drawing ballasted necessary keep steady jigs angles correct whole business symmetri cal connect spruce spars project fuselage bay spruce cut shape like epoxy job its quick drying strong main spar connected repeat rear spar shaped front balsa spars have joined since main spar its doubled Y configuration provides strength enough Remove inner wing jigs beef up spar assembly vertical grain balsa join has taken place Check eye looks good Add three-ply faces spar make extremely serviceable cen ter section job have specific use well provide location brack ets accept nylon bolts attach fuselage wing Trial fit fuselage main part wing making usual adjustments alterations get right wing root ribs should bed nicely cutaway part fuselage wing must dead square fuselage centerline Continued page 138 60 Model Aviation Left The left wings outer panel Du-Sro quarter-turn latches secure inspection hatch twin belicrank elevator con nected servo cables Note lower edge rudder prolects forward way aft end tail wheel mount RC Helicopters/Jolly Continued page 135 possible go flybarless rotor head Ive flying GMPs heads flybarless several years now have excellent re suits modifying following way center yoke bandsawed off top machined portion head head assembled normally except damp ening must tight possible Rang ers ran GMP blades cut rotor diameter 58 blade ballasted center-of-gravity-corrected weight 190 grams Set up way ships superb fly Because use no mixer headjust two links direct swashplateI must cut down collective cyclic throws can quite excessive try heads flybarless just make sure dampening tight throws reduced head gets normal pitch changes youll really like flying flybarless Also 190-gram blades autorotations dream fact night flying Rangers just set down ground Being cute hit throttle hold pulled up collective head has much inertia Helicopter lifted higher head settled slowly back ground thought sure would run out blade speed bend bird up honest soft touchdown achieved So finished three Rangers time shipped ahead Globe AZ film ing would take place arrived two days later uncrated beauties finding minimal damage flicted air freight kind winced found Out would flying elevation 4000 ft Believe nothing gets director excited watch ing flying bomb winding up wanting lift off loaded 13 lb Cobra/ Rangers flew excellentlyeven altitude Franidy after building three Helicopters shipping location span month flying anticlimactic director picked out rock face locked off two high-speed cam eras panned two hit spot first time Id used real explosives like potassium nitrate primer cord weird have machine strike wall see flash observe total disintegration fuselage mechanics falling ground As loaded up after destroying third ship thinking grateful could de pend various model companies provide quality equipment capable doing job safely Anyway see Midnight Run look small part model aviation played give believable explosion New GMP machine coming Gorham Model Products has just given permission nounce new aerobatic Helicopter Leg end have flown prototype can tell Legend quite capable dar ing acrobatic maneuvers GMP will showing ship Toledo made show saw public display first time Anyway Legend still cooperative ef fort between Gorham Hirobo lot Gorham Legend features flybar less rotor head toothed-belt tail rotor drive ex tremely light weight John says de mostly two new space age materials called aluminum steel As soon can get some pictures Ill give preview BCNU Wellesley/Pelly-Fry Continued page 60 thin three-ply flaps split type hinged rear spar three points side flaps lightly braced fore aft along inside span make rigid Small cutaways under wing accommodate will give snug fit flap bellcrank fitted coincide servo location Using servo flap merely conveni ent rather technical necessity Its easy harmonize two servos adjust ments devises method constructing wing out ers same main inner wing ailerons having recessed hinge Set up port starboard wings spe cially made jigs making provision three degrees washout cut sand soft balsa wing tips shape glue place Finish covering outers nylon Before constructing ailerons provide access aileron bellcranks using Du Bro quarter-turn latches As shown drawing aileron consists basically number balsa ribs half-round lead ing edges aluminum tube spar located fat point rib section trailing FOAM WING CORES muuumuu.uuuuuumummu.uuuuuuuuuuu.uuummm U U I PRECISION MADE EXPANDED BEAD POLYSTYRENE REPLACEMENT WING & STAB CORES FOR ALLI POPULAR RIC AIRCRAFT OVER 250 DIFFERENT WINGS IMMEDIATE DELI VERE SO IF YOU HAVE U AFAVORITEBIRD THAT NEEDS WING CALL OR WRITE USI I- SEND $350 FOR OESCRIPTIVB PRODUCT CATALOGj I U U U U II U U U U U uuuemmuuumumuUUuuuuuummmuuum..~... /VG MFG WING MPG P0 BOX 33 CRYSTAL LAKE IL 60014 p p pg S 0 AMERICAN JR OM RIDGE CAMPBELL T RITE DUBRO EASY BUILT MODELS FLYLINE FOX BERG DUBOIS LOW K&B MICRO X OS MAX RA PECK-POLYMER ECT MODELS SEAGLEN STERUNG IVAN SUPER TIGER INDER PLITE LER WILLIAMSS PRODUCTS RS ESTES MODEL ROCKETS Send Si Caeh Cheek ow Stamp eur 32 page tabloid size DISCOUNT Catalog 900 jItosttions ove 700 Kits choose Io, MAILOROER PHONEORDER IN STORE PENN VALLEY HORNY CENTER 837 1 Main St LansdalmVa 19445 138 Model Aviation REPRODUCTION PARTS FOR ANTIQUE IGNITION ENGINES o SPARK PLUGSa TANK TOPSa POINTS o TIMERSo GASKETSoTANKS o NEEDLE VALVESa SCREW SETSo COILS o EXHAUST STACKSe MANUALSa PROP DRIVES OVER 1000 ITEMS FOR MORE THAN 60 ENGINES SEND $4 FOR 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Edition: Model Aviation - 1988/06
Page Numbers: 52, 53, 54, 55, 56, 57, 58, 59, 60, 138
EGroup Captain James Pelly-Fry Unique construction hallmark RAF bomber Brit ish used Ethiopia against Mussolini during early years WW II RC model design bit history come us men actually flew full-size plane action PART OF THE ROMANCE Scale aero modeling lies rescuing obscure forgot ten long-lost aircraft oblivion giving second life Searching details data necessary recreate old aircraft satisfying itself also adds another dimensionthe thrill huntto rewards pleasures acquiring expertise model builder Vickers Wellesley example just such long-forgotten discarded air craft long-range single-engine RAF bomber piloted World War II uncommonly efficient construction interesting history well worth know ing about brainchild Sir Barnes Wal lis Later war designed airships bouncing bomb destroyed huge dams Germany Wellesley flown successfully day night over Ethiopia against Mussolinis forces remarkable aircraft possessed ex ceptional load-carrying capabilityeven standard form could lift much its own weight 1938 three specially equipped Wellesleys flown nonstop over 48 hours Egypt Australiaa just-over-7 000-mile trip overturned world record distance held until Russia Fifty years ago 7000 unbroken miles fairly impressive achievement privileged command Wellesley squadrons having served second-in-command another squadron earlier war found air craft well exceeded expectations also piloted Douglas A20 Bob Wis cher has successfully built test flown Flying Scale model Wellesley comes second scaled-down version 52 Model Aviation Top extra wingspan lightweight construction enabled long-range RAF bomber lift much its own weight Above Its great thrill resurrect old de sign its particularly exciting bring plane back since no full-size version remains one-time military prototype person ally flew aviator As full-size aircraft both Douglas Wellesley did su perlative job very different wartime cir cumstances both have equal place sentiments salient characteristics Welles ley its very large wingspan 74 ft prototype good news model version use unique form air frame construction Barnes Wallis called geodetic consisting essentially double-spiral structure fuselage what might called basket weave wing stabilizer geodetic construc tion gave Wellesley exceptional light ness strength cardinal rule airplane design wing particular both extremely light very strong So far know single Wellesley specimen has recovered posterity left desert fate after Allied Forces moved Southern Europe Thus designing scaled-down version worthy aircraft researchthe aforementioned huntwould have lim ited whatever drawings sketches photographs could obtain Beaumont Avi ation London specializes keep ing records aviation data old maga zines books etc supplied some valuable material fortuitous coincidence also helped Matchbox Model Company recently produced 12-in-span stick together Wellesley kit ex Construction Once sufficient data work has collected piv otal step Scale design decide upon suitable scale choose hardware determined rest followsprob lems Wellesley after doing some figures back old enve lope chose Mo-scaleas RAF Boston counterpart A20 way Id get big wing keep wing loading down reasonable figuresthe perennial aim often eludes Scale modeler wingspan would 90 hoped get weight down around eight pounds power plant Enya 40-4C fourstroke seemed promising Id successfully fitted pair A20 RAF Bos ton case also happened have engines spare good friend Bud Voss uncertainty con cerned whether Enya sufficient power get big Wellesley airborne June 1988 53 cellent material supplied cooperative manufacturer got started proj ect Top particular model version plane once flew 223rd RAF Squadron Wellesley set distance world record 7000 continuous miles 1938 Above author rendition bombers piloted actually serving squadron commander during World War II scaled down one-tenth actual size big model flying safely Enya proved equal task landing gear supposed tail-down retractable job decided stay proven productthe excellent Rom-Air type As Boston gives creditable service very high wing loading sometimes occasions dramatic arrivals touchdown seemed natural choice use known entity Fuselage Fairly conventional construction used geodetic inner framework omitted sake weight-watch ing leaving four longerons stringers prototype establish correct oval shape cross section practice fabric covering used aft pilots cockpit course number flats sufficient number stringers employed maintain gen eral oval shape critical eye fuselage made up two halves using datum line straight along center line between top bottom halves method gives good foundation construction Mosquito employed es sentially same procedure dif ference being Mossie fuselage joined up top-and-bottom rather like chocolate Easter egg A-in-thick three-ply bulkheads TO I MAKE 2 MAKE RU 3RINS MA TRIM MAPLE MOTOR M U SHAPE BRA1 SCALE VOKES CARB FROM BALSA RLOCKS EV RUDDER SEEN PROM REAR H VB I/5 BALSA POST3 3/16 BALSA PIN 7 RUDDER F AME / I/I6 BALSA RI RINSEN LOCATION S TRIMTAB--H MUSC WRE TAILWHEE7 BRACEjXB BALSANOTSH BLOCKASEE TE XDETA LS S DA TALWHEEL 0IS345 constructed drawings appro priately slotted take north-south east-west longerons intermediate stringers completed cut across horizontal centerline using razor saw removes minimum timber useful number bulkhead go situated behind pi lots canopy has duplicated provide endpiece removal hatch reason make sure lower halves twin bulkhead glued gether top halves just lightly spot glued subsequent separa tion double lower bulkhead gives added strength rear spar wing passes through fuselage later Lay out full-size drawing top view fuselage building board steam shape first pair 4 x A-in spruce obechi sticks lie flat joined together 54 Model Aviation Using run-up table makes easier get everything assembled perform engine adjustments See text details making polystyrene external bomb containers Operating flaps slow big model down floating touchdowns add realism real beauty model lies just below its skin unique geodetic construction used designer Barnes Wallis give Wellesley lots strength lots weight Full-Size Plans Available. See Page 164 F WOOS .ASS B EPOXY ENGINE ORBOMB BOX IS MADE FROM FOAM BLOCK AND COVERED WITH FIBERGLASS EPOXYBOOS SUPPORT FRONT VIEW SCRAP WOOD SUPPORTS SAND TO AIRFOIL SHAPE SIDE VIEW USELAGE TOP VIEW NOTE FORMERS B THRO H ARE I/B PLYWOODTRIM AND NOTCH PER B F FIN CROSS IONREAR CLEAR PLASTIC CANOPY ENS SERB lIlY RUCTION FUSELAGE SIDE VIEW BOMB BOX y C I/4 PLY 1/B PLY -FORMERS-___ ---____________________ --I/G SO BALSA STRINGERS SPAR LINE I/4 I/lB BALSA LONG ERONS FIBERGLASS TOWNEND RING -x I/RPLYWOOO1/4 PLYWOOD / II LS MAPLE MOTOR MOUNTS K I FORWARD CLEAR PLASTIC CANOPY CLEARFUEL TANK PLASTICREMOVABLEVENTS WINDOWHATCH LINE C/771 E5OZFUELTANK SI/lB PLY FLAPS FLAP HORN ELEVATOR SERVO-i 2-I/ST INCIDENCE CS Y\ELAEJ--LSRyg I/32 PLY WHEEL COVERS WHEELS RCVR 5rNI II - ERY lID 3/B MAPLE MOTOR MOUNTS CLEAR PLASTIC WINDOW FIBERGLASS TOWNEND /1 oif i$ 40- 4 CYCLE ENGINE --c- I-S/B DIA SPINNER SHEET OF 2 MODEL AVIATION VICKERS WELLESLEY DESIGNED BY GRP CAPT JAMES PELLY FRY TRACING BY JOE DEMARCO RESERVED counterparts form completed longe rons Having pinned two sticks down securelyI pin either side through themtake top half-bulkhead hoop sequence glue its correct location Its best time hoop pretty unstable its small base halfbulkhead hoops glued position quick results used epoxy sup ported hoop anything handyso long hoop remained dead upright dur ing glue setting front bulkhead dou ble thickness ply strength Steam bend shape top longe rons again 1/4 x % Slot glue half-bulkhead hoops Slot glue %-in-sq balsa string ers fitting alternately avoid distor tion top half fuselage semicomplete sturdy enough handle re move building board An Enya 40 four-stroke provided plenty power model Note wire remote glow plug connector fuselage beams may look flimsy theyre plenty strong enough June 1988 55 drawing Place somewhere level weights bottom longerons pre serve true shape begin over again construction lower half fuselage constructing fuselage half keep mind its unnecessary stringers go way back theres much room anyway thin back end So its good idea shorten other suit eye case remove stringers last bay tail unit located Another im portant reminder Take great care second half fuselage duplicates first exactly possible particu larly true midpoint longerons must either glued fitted together inspection access hatch location Its impor tant take pains craftsmanship early stage project After checking two identical fu selage halves join together exactly apply glue along edgeswith important exception front half longe rons will glued just fitted gether what call touching fit around inspection hatch area youll separating hatch razor blade later Bring faces both glued fitted together secure along entire length springloaded office-type bulldog clipsvery handy grip firmly can fitted hand now have nicely shaped fairly stiff fuselage frame oval bulkheads have rigidity will ever needthe nylon covering add later will support moreand fuse lage length joined-up parts become good strong 14 x A-in-sq section forming master longerons along centerline Before setting aside masterpiece Im sure family friends will agree remove stringers last end bay tail unit will located will later replaced super-thin three-ply screwed place form ac cess hatches main hatch up front quick-remove can temporarily left spot glued place allow get used its new shape Empennage greatest need back end maximum lightness combined adequate strength flight ground handling fraction superfluous weight tail model roughly equivalent putting four times much nose Building light tail order exact weight penalty cannot stressed too strongly too often par ticularly Scale modeling basic layout prescribed external shape prototype builder finds after installing essential items like en gine fuel tank servo radio battery etc well up front still needs add much-dreaded ballast correct balance point Some Scale models need much two pounds lead squeezed nose offset tail weight thats terrible handicap Models short noses present biggest problems thus tend avoided Because requirement lightness materials stabilizer elevators fin rudder chosen great care kept judicious minimum wood primarily soft balsa plus small amount hard balsa little / super birchwood ply made Finlandthe latter strengthen both sides stabilizer main spar rudder post thin ply glued side separately keeping little oversize sanding down shape spars taper slighfly out tips theyre made up check twist during construction theyre weighted down during gluing allowed dry out well will remain straight true 2-in aluminum tube used connect elevators attach homemade control horns As fuselage make empen nage over drawings ensure accurate shape subtle curves give model its realism stabilizer distin guished its lattice-work geodetics elevators slightly off-center i/B PLY R-5~21/8 PLY EL I/B 1/5 BALSA 8-7 SMALL HINGES TO SUIT F SOFT BALSA BLOCK WING liPS HI LI STABILIZ GE IC LINES I/E S/lB BALSA-KEEP IT LIGHT-GEE TEST DETAILS BUILD FRAME FROM LAMINATES BALSA CROSSSECTION ALSALES R Left The air tank Rom-Air retracts servo operates valve inspection covers held place six self-tapping screws blisters necessary accommodate wheels Right Small inner covers wheel wells closed wheel itself upon retraction gear down weighted arms small doors keep open Plastic straps cover hole gear up 56 Model Aviation Full-Size Plans Available. See Page 164 R-6I/B PLYY SPAR IS /41/16 SPRUCE I/B PLYBOMB BOX LOCATIONWITH BALSA VERY SRAIN WEBS HORN MOUNTSEE TEST LEFT WINGWINS JOINT -LINE PLYAILERONR-I HORNB-S N-SILERO N-B-SERV -R -N C --ROM-AI RETRAC/ CB-BASEPLA/ IN / APBEPUBOS P0AERV L SR ROD AILERONS ARE BUILT UP SPARREARWITH BMSA RIBS SEE TEXT PLYSPAR DIHEDRAL 5-1/5 2FLAPS ARE I/IN PLY UNDER WINS5/16 PLY PLY RIBSEOOETIC LINES I/IN SEEP BY S/B WIDE BALSA SECTION ROOT CHORDSEE TEXT FOR CONSTRUCTIONR-2% SIB BALSA LE TAPEREDI/B PLY -RIGHT WING B-S AlONB-SR R ERV -A- SERVO FLAP AILERON HORN VICKERS WELLESLEY PLY HORN I161JNT DESIGNED BY GRP CAPT JAMES PELLY FRY BALSA YE STOCK0IS54BBTRACING BY JOE DEMARCO IIIII IGHTS ft SHEET 2 OF 2 MODEL AVIATION horns avoid contact rudder fin-rudder assembly completed have full travel latter influenced conventional Use small plastic necessarily covered stage now shape inboard part eleva hinges slipped pre-cut slots cor- set up fuselage Make provision tors sweep stabilizer rect midline points frame glued foot spar rudder post spar practice Wellesley does minimum epoxy Check secur- spar standing glued onto small need much application rudder normal ity pulling gently hinge after block rudder course has move flight since ailerons epoxy has cured may next freely double arms horns must work model ailerons coupled day trick fitting stabilizer eleva tors fuselage cut away lead ing edge spar sufficiently enable maneuvered place Once thats done stand fuselage its nose floor steady glue main spar onto back rearmost bulkhead midpoint Theres very little room area work carefully accurately mak ing sure stabilizer dead square fuselage upright Once epoxy has set can build up broken lead ing edge short piece hard balsa glued bulkhead along side using filler piece necessary June 1988 57 Detail geodetic wing construction locations aileron flap servos Left Band-sawing soup can half soldering tin across flat bottom resulted nice looking custom fuel tank Right molding tools beds used make canopies see text details right aerodynamically clean Townend cowl rudder least time being may change separate controls later Once again rehearse final assembly glu ing making sure everything true accurate beforehand Replace stringers cut away earlier last end bay fuselage four shaped pieces / ply will provide access moving parts tail elevator rudder steerable tail wheel builder prefers stringers can left out first place since chance fuselage twist slight four small very light panels secured bulk heads very small self-tap screws spare weight put just enough no little visual embellish ment adds almost nothing weight quarter-section ping pong ball can fitted glued edge top half rear bulkhead elevator rudder controls closed-loop type Closed-loop systems work fine save weight used very lightweight fishing trace wire nylon cov ered should no 10-lb break ing strength assembling servo coupling up wires use miniature fishing tackle swivels servo end fish ing gear ferrules trap wire coupling up nip two wire cutters advantage swivels can ad just correct tension removing clevis worse twisting wire Allow enough slack wires can move sideways about midpoint end-to-end approximately ly tight wires bad servos steerable tail wheel 2 A-in dia light can find mounted made-up fork piano wireabout 16-gauge just stiff enough job Bind ends thin wire solder lightly slide piece aluminum tube glue epoxy Trim wire ends unit fits another tubeyou want nice sliding fitwhich epoxied built-up unit fuselage use balsa pieces give rigidity Test smooth movement Make up own crank horn carefully epoxy collar type used landing wheels Locked grub screw collar traps inner tube top projects above bear ing its horn connects arm rudder horn now have good steer able tail wheel adjustable cor rect tracking taking off taxiing also removable neces sary book neat taxiing straight down-the-dotted-line takeoffs add re alism model flight point backtrack front end fuselage few major jobs have done before proceeding other work make access cover removable b cut away part fu selage form air-gunner/radio mans position make pilots gunners canopies c cut away part fuse lage underside accommodate wing root double spars make hatch access cover remov able begin slipping razor blade tween centerline longerons break spot gluing will free cover nicely help retain its shape after removing cover fit small strut across back hatch fit front would prevent putting taking off cover cover off glue place double-thickness front bulkhead gluing bottom half hatch cover now has no forward movement Prevent side ways movement fitting little feet hatch cover slip inside longerons Make small adjustments hatch fits snugly position secure nylon bolts small platforms glued bulk heads inside fuselage can take cap tive nuts Recessed bolts help appearances Making pilots gunners canopies first think about awhile Since chance finding anything ready-made approximates right size shape nil have no op tion make yourself method chose heat-mold oven using molding tool finding way position clear acetate sheet securely newly found expertise area welcome Choose piece balsa big enough task Using drawings perhaps photographs carve sand pretend can opy will sit place fuselage inside part sits nicely either before after cutting away unwanted part fuselage begin carve shape canopy itself Balsa easy work type job since lot so-called carving reality coarse sanding rather actual shaping carvers tool solid balsa canopy appears just right eye make hole underpart crea tion accept handle choice used 4-in length -in doweling sure epoxy handle well has work canopy-and-handle unit serves molding tool Give good hard var nish Next make wood bed little bigger plan size tool sup ported feet high enough tool can go through matching hole mat tress leaving bit space say around can move tool out nicely take piece thin acetate sheet pin way around close hole push pins work fine Now comes fun part things 58 Model Aviation seems shame hide structural work like underneath covering Scale model full-size bombers have never known fOr having see-through wings Left Inside structure details cockpit hatch Right one-piece removable cockpit hatch give total access inner workings quiet kitchen mama out shop ping turn electric oven maxi mum heat oven has preheated high will go put bed metal tray oven leaving main door open inner glass door shut Watch what happens closely After about minute will see acetate beginning ripple meaning has softened heat Before collapses take out bed its tray grab tool pronto push firmly hole bed acetate has softened correctly tool will force accept its shape have lucky tool will now below mat tress level will soon cool its cool enough handle gently wiggle tool back forth until sepa rates acetate now has just shape intended Remove bed trim off frilly part skirt its set fitted fuselage Dont expect good results first time tempt heat-mold procedure its bit knack get right may need try before youre successful pilots canopy after final trimming nice fit can edge glued place Use short lengths masking tape hold position during setting gunners can opy prototype quite cleverly hinged its opened back half becomes windshield front part disappears inside fuselage Wellesley gunners kept canopy open al time being very little air turbulence generally warm air over Af rica Making models canopy swivel though would have complicated also impractical standpoint canopy will stiff using thin ac etate sheet permanently closed want realism swivel can opy no harm trying make gunners canopy permanently closed dont forget make up lifelike Lewis gun mount cut slot fixed metal com partment prototype rear canopy stowage gun task cutting away part fuse lage underside accommodate wing spars may done now left until after main part wing has con structed modelers discretion latter sequence may better either way method same After marking unwanted areasthe main spar thin rear sparcut out fretsaw knife building up ends big cutaway ply shape upper line cutout must coincide root wing ribs idea being fu selage fits onto wing other way around low-slung wing Vickers Wellesley Mk 1 Single-engined RAF tight bomber Model scale 1/10th based L2714 wartime identity letters AO-A No 223 Squadron RAE Dimensions Wingspan895 Wing area6298 sq ft 907 sq Wing sectionRAE32 Root chord15in Tip chord65in mci balsa tip Aspect ratio88 Fuselage length47in Wing dihedral21/20 Wing washoutouters30 Engine Enya 40-4C four-stroke 65cc 1/2 hp PropellerTornado reinforced nylon 121/2 x 5 Maximum rpm ground run 8500 Weights Fuselage tail unit motor fuel tank 43 oz Wing complete Rom-Air gear z Radio8 servos 6 channels 18 oz Bomb containers 4 oz FuelS fluid oz 4 oz Total 127 oz 7 lb 15 oz Nominal 2 oz ballast added damp down elevator response necessary Wing loading 8 lb wt 0 ozIsq ft Control throwsat trailing edge Elevator way Rudder 1 way Ailerons % up % down Flaps 11/2 full down approx 400 makes sense have supporting fuse lage times Dont dismayed small amount fuselage material re mains after the big cutout accommo dating wing has made hatch removed isnt cause con cern Suitably strengthened balsa planks favorite /64 ply side its frame fuselage tougher appearsready perils flying life crashes Once three jobs done rest fuselage construction basically con ventional spiced few specific adapta tions Two beechwood engine bearers 5 long in cross section slotted bulkheads also pro vide platform special fuel tank slightly offset make room engine servoa snug fit space available Its remarkable much design work has done certain areas ac commodate essential items Once engine bearers have fitted supplementary platforms radio gear ser vos etc can provided suit individual preference however recommend locate everything along lines Wellesley way youll least know everything works together logical fashion have good access parts space behind Enya 40-4C engine front bulkhead filled aluminum sheet cowl top half shaped paper pattern made ear lier screwed thick front bulkhead bottom half thin ply glued place pilots cockpit also part fuse lage construction After cutting out small cockpit area hatch cover make wooden replica windshield framework will probably have noticed order simulate solid front sec tion fuselage going back far cockpit balsa sticks have sandwiched between longerons stringers solid structure nicely sanded down sists making neat job cockpit sur round windshield frame made match drawing applies equally canopy minor trimming can June 1988 59 opy will needed before final test fit gluing Make certain however thing position before glue since af terwards youll have no further access cockpit except inside hatch removed simulated glass windshield panels made clear Plexiglass cut thick enough look good little care shaping panel before gluing will give realistic ap pearance Dont forget human eye tends look things some kind prior ity case Scale model its cockpit area attracts Wing Wellesley somewhat other airplane Im familiar constructing wing key crucial step model priority consideration get near geo detic construction prototype possi ble Almost important decision use well-proven system removable outer wings Boston radio setup dictated fact fuselage would sit wing just four bolts keep decided mount aileron flap servos together Rom-Air unit wing accommodating other components within fuselage makes preflight assemblyand post-flight disassemblyas simple foolproof possible As prototype starting point wing construction Y-shaped main spar design gives great strength its needed also accommodates landing gear nicely spar fashioned primarily top bottom sticks 14 x /16 spruce supplemented vertical grain balsa webs beefed up ply facing near wing roots before assembly spars very sturdy initial stages construction wing structure consists four master ply ribs distributed along inner wing assem bly shown drawings cut trimmed glued position Cut small narrow vertical slots outboard master ribs accommodating wing joiners refer plans Port star board wings constructed separately spruce spars projecting two inches beyond wing root ribs form struc ture center section Place wing skeleton wing plan drawing add balsa shaped leading edge spar rear spar latter built up -in strip balsa medium hard / ply facings Glue face separately ply being little oversize sand down afterwards will get light stiff spar trouble three spars glued integrally four master ribs before begin ning geodetic construction phase install balsa platforms flap aileron servos according drawing loca tion seems work out fine given de sign factors involved access panels very thin ply can secured very small self-tap screws suitably posi tioned small hardwood blocks no need quick access field Youre now ready turn two halfwing skeletons geodetic ones Using geodetic lines drawing roughly correspond prototype pre pare large quantity balsa sticks /16 soft sheet balsa about % wide Work ing along panel upper part frame cut fit sticks edge up herringbone pattern Run same pattern opposite direction cutting fitting sticks slot original ones creates arrangement diamond shapes squares somewhat resembling egg-crate An important point remember sticks positioned little higher wing contour Next make sanding stick Cover straight batten about 1 x 114 just little longer span half-wing sandpapercoarse side fine other halfwing lap begin sanding evenly across span structure working grain balsa sticks wherever possible Soon wing contours begin show have sanded down almost point touching master ribs use fine sandpaper finish off now have nicely shaped accurate tapered wing geodetic construction wing has strength spare could fact build acceptably strong using less material wing gener ously built still light needs hold back RAF 32 airfoil dupli cates the prototype par ticular airfoil must can substi tute nice-looking NACA biconvex version thats minimum two inches deep root chord Once first wing half looking good topside turn over create same airy basket weave contours underside Repeat process both sides other wing half routine beginning stale least know end product justifies means Wellesleys geodetic wing singularly twist-free light Now youre ready join wing pan els together first step make jigs support wings positioned drawings jigs must provide secure base give necessary 2 0 dihe dral prototype Equally important wing half must have precisely identical rigging angles fore aft pays work carefully accurately process wings carefully positioned over drawing ballasted necessary keep steady jigs angles correct whole business symmetri cal connect spruce spars project fuselage bay spruce cut shape like epoxy job its quick drying strong main spar connected repeat rear spar shaped front balsa spars have joined since main spar its doubled Y configuration provides strength enough Remove inner wing jigs beef up spar assembly vertical grain balsa join has taken place Check eye looks good Add three-ply faces spar make extremely serviceable cen ter section job have specific use well provide location brack ets accept nylon bolts attach fuselage wing Trial fit fuselage main part wing making usual adjustments alterations get right wing root ribs should bed nicely cutaway part fuselage wing must dead square fuselage centerline Continued page 138 60 Model Aviation Left The left wings outer panel Du-Sro quarter-turn latches secure inspection hatch twin belicrank elevator con nected servo cables Note lower edge rudder prolects forward way aft end tail wheel mount RC Helicopters/Jolly Continued page 135 possible go flybarless rotor head Ive flying GMPs heads flybarless several years now have excellent re suits modifying following way center yoke bandsawed off top machined portion head head assembled normally except damp ening must tight possible Rang ers ran GMP blades cut rotor diameter 58 blade ballasted center-of-gravity-corrected weight 190 grams Set up way ships superb fly Because use no mixer headjust two links direct swashplateI must cut down collective cyclic throws can quite excessive try heads flybarless just make sure dampening tight throws reduced head gets normal pitch changes youll really like flying flybarless Also 190-gram blades autorotations dream fact night flying Rangers just set down ground Being cute hit throttle hold pulled up collective head has much inertia Helicopter lifted higher head settled slowly back ground thought sure would run out blade speed bend bird up honest soft touchdown achieved So finished three Rangers time shipped ahead Globe AZ film ing would take place arrived two days later uncrated beauties finding minimal damage flicted air freight kind winced found Out would flying elevation 4000 ft Believe nothing gets director excited watch ing flying bomb winding up wanting lift off loaded 13 lb Cobra/ Rangers flew excellentlyeven altitude Franidy after building three Helicopters shipping location span month flying anticlimactic director picked out rock face locked off two high-speed cam eras panned two hit spot first time Id used real explosives like potassium nitrate primer cord weird have machine strike wall see flash observe total disintegration fuselage mechanics falling ground As loaded up after destroying third ship thinking grateful could de pend various model companies provide quality equipment capable doing job safely Anyway see Midnight Run look small part model aviation played give believable explosion New GMP machine coming Gorham Model Products has just given permission nounce new aerobatic Helicopter Leg end have flown prototype can tell Legend quite capable dar ing acrobatic maneuvers GMP will showing ship Toledo made show saw public display first time Anyway Legend still cooperative ef fort between Gorham Hirobo lot Gorham Legend features flybar less rotor head toothed-belt tail rotor drive ex tremely light weight John says de mostly two new space age materials called aluminum steel As soon can get some pictures Ill give preview BCNU Wellesley/Pelly-Fry Continued page 60 thin three-ply flaps split type hinged rear spar three points side flaps lightly braced fore aft along inside span make rigid Small cutaways under wing accommodate will give snug fit flap bellcrank fitted coincide servo location Using servo flap merely conveni ent rather technical necessity Its easy harmonize two servos adjust ments devises method constructing wing out ers same main inner wing ailerons having recessed hinge Set up port starboard wings spe cially made jigs making provision three degrees washout cut sand soft balsa wing tips shape glue place Finish covering outers nylon Before constructing ailerons provide access aileron bellcranks using Du Bro quarter-turn latches As shown drawing aileron consists basically number balsa ribs half-round lead ing edges aluminum tube spar located fat point rib section trailing FOAM WING CORES muuumuu.uuuuuumummu.uuuuuuuuuuu.uuummm U U I PRECISION MADE EXPANDED BEAD POLYSTYRENE REPLACEMENT WING & STAB CORES FOR ALLI POPULAR RIC AIRCRAFT OVER 250 DIFFERENT WINGS IMMEDIATE DELI VERE SO IF YOU HAVE U AFAVORITEBIRD THAT NEEDS WING CALL OR WRITE USI I- SEND $350 FOR OESCRIPTIVB PRODUCT CATALOGj I U U U U II U U U U U uuuemmuuumumuUUuuuuuummmuuum..~... /VG MFG WING MPG P0 BOX 33 CRYSTAL LAKE IL 60014 p p pg S 0 AMERICAN JR OM RIDGE CAMPBELL T RITE DUBRO EASY BUILT MODELS FLYLINE FOX BERG DUBOIS LOW K&B MICRO X OS MAX RA PECK-POLYMER ECT MODELS SEAGLEN STERUNG IVAN SUPER TIGER INDER PLITE LER WILLIAMSS PRODUCTS RS ESTES MODEL ROCKETS Send Si Caeh Cheek ow Stamp eur 32 page tabloid size DISCOUNT Catalog 900 jItosttions ove 700 Kits choose Io, MAILOROER PHONEORDER IN STORE PENN VALLEY HORNY CENTER 837 1 Main St LansdalmVa 19445 138 Model Aviation REPRODUCTION PARTS FOR ANTIQUE IGNITION ENGINES o SPARK PLUGSa TANK TOPSa POINTS o TIMERSo GASKETSoTANKS o NEEDLE VALVESa SCREW SETSo COILS o EXHAUST STACKSe MANUALSa PROP DRIVES OVER 1000 ITEMS FOR MORE THAN 60 ENGINES SEND $4 FOR 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Edition: Model Aviation - 1988/06
Page Numbers: 52, 53, 54, 55, 56, 57, 58, 59, 60, 138
EGroup Captain James Pelly-Fry Unique construction hallmark RAF bomber Brit ish used Ethiopia against Mussolini during early years WW II RC model design bit history come us men actually flew full-size plane action PART OF THE ROMANCE Scale aero modeling lies rescuing obscure forgot ten long-lost aircraft oblivion giving second life Searching details data necessary recreate old aircraft satisfying itself also adds another dimensionthe thrill huntto rewards pleasures acquiring expertise model builder Vickers Wellesley example just such long-forgotten discarded air craft long-range single-engine RAF bomber piloted World War II uncommonly efficient construction interesting history well worth know ing about brainchild Sir Barnes Wal lis Later war designed airships bouncing bomb destroyed huge dams Germany Wellesley flown successfully day night over Ethiopia against Mussolinis forces remarkable aircraft possessed ex ceptional load-carrying capabilityeven standard form could lift much its own weight 1938 three specially equipped Wellesleys flown nonstop over 48 hours Egypt Australiaa just-over-7 000-mile trip overturned world record distance held until Russia Fifty years ago 7000 unbroken miles fairly impressive achievement privileged command Wellesley squadrons having served second-in-command another squadron earlier war found air craft well exceeded expectations also piloted Douglas A20 Bob Wis cher has successfully built test flown Flying Scale model Wellesley comes second scaled-down version 52 Model Aviation Top extra wingspan lightweight construction enabled long-range RAF bomber lift much its own weight Above Its great thrill resurrect old de sign its particularly exciting bring plane back since no full-size version remains one-time military prototype person ally flew aviator As full-size aircraft both Douglas Wellesley did su perlative job very different wartime cir cumstances both have equal place sentiments salient characteristics Welles ley its very large wingspan 74 ft prototype good news model version use unique form air frame construction Barnes Wallis called geodetic consisting essentially double-spiral structure fuselage what might called basket weave wing stabilizer geodetic construc tion gave Wellesley exceptional light ness strength cardinal rule airplane design wing particular both extremely light very strong So far know single Wellesley specimen has recovered posterity left desert fate after Allied Forces moved Southern Europe Thus designing scaled-down version worthy aircraft researchthe aforementioned huntwould have lim ited whatever drawings sketches photographs could obtain Beaumont Avi ation London specializes keep ing records aviation data old maga zines books etc supplied some valuable material fortuitous coincidence also helped Matchbox Model Company recently produced 12-in-span stick together Wellesley kit ex Construction Once sufficient data work has collected piv otal step Scale design decide upon suitable scale choose hardware determined rest followsprob lems Wellesley after doing some figures back old enve lope chose Mo-scaleas RAF Boston counterpart A20 way Id get big wing keep wing loading down reasonable figuresthe perennial aim often eludes Scale modeler wingspan would 90 hoped get weight down around eight pounds power plant Enya 40-4C fourstroke seemed promising Id successfully fitted pair A20 RAF Bos ton case also happened have engines spare good friend Bud Voss uncertainty con cerned whether Enya sufficient power get big Wellesley airborne June 1988 53 cellent material supplied cooperative manufacturer got started proj ect Top particular model version plane once flew 223rd RAF Squadron Wellesley set distance world record 7000 continuous miles 1938 Above author rendition bombers piloted actually serving squadron commander during World War II scaled down one-tenth actual size big model flying safely Enya proved equal task landing gear supposed tail-down retractable job decided stay proven productthe excellent Rom-Air type As Boston gives creditable service very high wing loading sometimes occasions dramatic arrivals touchdown seemed natural choice use known entity Fuselage Fairly conventional construction used geodetic inner framework omitted sake weight-watch ing leaving four longerons stringers prototype establish correct oval shape cross section practice fabric covering used aft pilots cockpit course number flats sufficient number stringers employed maintain gen eral oval shape critical eye fuselage made up two halves using datum line straight along center line between top bottom halves method gives good foundation construction Mosquito employed es sentially same procedure dif ference being Mossie fuselage joined up top-and-bottom rather like chocolate Easter egg A-in-thick three-ply bulkheads TO I MAKE 2 MAKE RU 3RINS MA TRIM MAPLE MOTOR M U SHAPE BRA1 SCALE VOKES CARB FROM BALSA RLOCKS EV RUDDER SEEN PROM REAR H VB I/5 BALSA POST3 3/16 BALSA PIN 7 RUDDER F AME / I/I6 BALSA RI RINSEN LOCATION S TRIMTAB--H MUSC WRE TAILWHEE7 BRACEjXB BALSANOTSH BLOCKASEE TE XDETA LS S DA TALWHEEL 0IS345 constructed drawings appro priately slotted take north-south east-west longerons intermediate stringers completed cut across horizontal centerline using razor saw removes minimum timber useful number bulkhead go situated behind pi lots canopy has duplicated provide endpiece removal hatch reason make sure lower halves twin bulkhead glued gether top halves just lightly spot glued subsequent separa tion double lower bulkhead gives added strength rear spar wing passes through fuselage later Lay out full-size drawing top view fuselage building board steam shape first pair 4 x A-in spruce obechi sticks lie flat joined together 54 Model Aviation Using run-up table makes easier get everything assembled perform engine adjustments See text details making polystyrene external bomb containers Operating flaps slow big model down floating touchdowns add realism real beauty model lies just below its skin unique geodetic construction used designer Barnes Wallis give Wellesley lots strength lots weight Full-Size Plans Available. See Page 164 F WOOS .ASS B EPOXY ENGINE ORBOMB BOX IS MADE FROM FOAM BLOCK AND COVERED WITH FIBERGLASS EPOXYBOOS SUPPORT FRONT VIEW SCRAP WOOD SUPPORTS SAND TO AIRFOIL SHAPE SIDE VIEW USELAGE TOP VIEW NOTE FORMERS B THRO H ARE I/B PLYWOODTRIM AND NOTCH PER B F FIN CROSS IONREAR CLEAR PLASTIC CANOPY ENS SERB lIlY RUCTION FUSELAGE SIDE VIEW BOMB BOX y C I/4 PLY 1/B PLY -FORMERS-___ ---____________________ --I/G SO BALSA STRINGERS SPAR LINE I/4 I/lB BALSA LONG ERONS FIBERGLASS TOWNEND RING -x I/RPLYWOOO1/4 PLYWOOD / II LS MAPLE MOTOR MOUNTS K I FORWARD CLEAR PLASTIC CANOPY CLEARFUEL TANK PLASTICREMOVABLEVENTS WINDOWHATCH LINE C/771 E5OZFUELTANK SI/lB PLY FLAPS FLAP HORN ELEVATOR SERVO-i 2-I/ST INCIDENCE CS Y\ELAEJ--LSRyg I/32 PLY WHEEL COVERS WHEELS RCVR 5rNI II - ERY lID 3/B MAPLE MOTOR MOUNTS CLEAR PLASTIC WINDOW FIBERGLASS TOWNEND /1 oif i$ 40- 4 CYCLE ENGINE --c- I-S/B DIA SPINNER SHEET OF 2 MODEL AVIATION VICKERS WELLESLEY DESIGNED BY GRP CAPT JAMES PELLY FRY TRACING BY JOE DEMARCO RESERVED counterparts form completed longe rons Having pinned two sticks down securelyI pin either side through themtake top half-bulkhead hoop sequence glue its correct location Its best time hoop pretty unstable its small base halfbulkhead hoops glued position quick results used epoxy sup ported hoop anything handyso long hoop remained dead upright dur ing glue setting front bulkhead dou ble thickness ply strength Steam bend shape top longe rons again 1/4 x % Slot glue half-bulkhead hoops Slot glue %-in-sq balsa string ers fitting alternately avoid distor tion top half fuselage semicomplete sturdy enough handle re move building board An Enya 40 four-stroke provided plenty power model Note wire remote glow plug connector fuselage beams may look flimsy theyre plenty strong enough June 1988 55 drawing Place somewhere level weights bottom longerons pre serve true shape begin over again construction lower half fuselage constructing fuselage half keep mind its unnecessary stringers go way back theres much room anyway thin back end So its good idea shorten other suit eye case remove stringers last bay tail unit located Another im portant reminder Take great care second half fuselage duplicates first exactly possible particu larly true midpoint longerons must either glued fitted together inspection access hatch location Its impor tant take pains craftsmanship early stage project After checking two identical fu selage halves join together exactly apply glue along edgeswith important exception front half longe rons will glued just fitted gether what call touching fit around inspection hatch area youll separating hatch razor blade later Bring faces both glued fitted together secure along entire length springloaded office-type bulldog clipsvery handy grip firmly can fitted hand now have nicely shaped fairly stiff fuselage frame oval bulkheads have rigidity will ever needthe nylon covering add later will support moreand fuse lage length joined-up parts become good strong 14 x A-in-sq section forming master longerons along centerline Before setting aside masterpiece Im sure family friends will agree remove stringers last end bay tail unit will located will later replaced super-thin three-ply screwed place form ac cess hatches main hatch up front quick-remove can temporarily left spot glued place allow get used its new shape Empennage greatest need back end maximum lightness combined adequate strength flight ground handling fraction superfluous weight tail model roughly equivalent putting four times much nose Building light tail order exact weight penalty cannot stressed too strongly too often par ticularly Scale modeling basic layout prescribed external shape prototype builder finds after installing essential items like en gine fuel tank servo radio battery etc well up front still needs add much-dreaded ballast correct balance point Some Scale models need much two pounds lead squeezed nose offset tail weight thats terrible handicap Models short noses present biggest problems thus tend avoided Because requirement lightness materials stabilizer elevators fin rudder chosen great care kept judicious minimum wood primarily soft balsa plus small amount hard balsa little / super birchwood ply made Finlandthe latter strengthen both sides stabilizer main spar rudder post thin ply glued side separately keeping little oversize sanding down shape spars taper slighfly out tips theyre made up check twist during construction theyre weighted down during gluing allowed dry out well will remain straight true 2-in aluminum tube used connect elevators attach homemade control horns As fuselage make empen nage over drawings ensure accurate shape subtle curves give model its realism stabilizer distin guished its lattice-work geodetics elevators slightly off-center i/B PLY R-5~21/8 PLY EL I/B 1/5 BALSA 8-7 SMALL HINGES TO SUIT F SOFT BALSA BLOCK WING liPS HI LI STABILIZ GE IC LINES I/E S/lB BALSA-KEEP IT LIGHT-GEE TEST DETAILS BUILD FRAME FROM LAMINATES BALSA CROSSSECTION ALSALES R Left The air tank Rom-Air retracts servo operates valve inspection covers held place six self-tapping screws blisters necessary accommodate wheels Right Small inner covers wheel wells closed wheel itself upon retraction gear down weighted arms small doors keep open Plastic straps cover hole gear up 56 Model Aviation Full-Size Plans Available. See Page 164 R-6I/B PLYY SPAR IS /41/16 SPRUCE I/B PLYBOMB BOX LOCATIONWITH BALSA VERY SRAIN WEBS HORN MOUNTSEE TEST LEFT WINGWINS JOINT -LINE PLYAILERONR-I HORNB-S N-SILERO N-B-SERV -R -N C --ROM-AI RETRAC/ CB-BASEPLA/ IN / APBEPUBOS P0AERV L SR ROD AILERONS ARE BUILT UP SPARREARWITH BMSA RIBS SEE TEXT PLYSPAR DIHEDRAL 5-1/5 2FLAPS ARE I/IN PLY UNDER WINS5/16 PLY PLY RIBSEOOETIC LINES I/IN SEEP BY S/B WIDE BALSA SECTION ROOT CHORDSEE TEXT FOR CONSTRUCTIONR-2% SIB BALSA LE TAPEREDI/B PLY -RIGHT WING B-S AlONB-SR R ERV -A- SERVO FLAP AILERON HORN VICKERS WELLESLEY PLY HORN I161JNT DESIGNED BY GRP CAPT JAMES PELLY FRY BALSA YE STOCK0IS54BBTRACING BY JOE DEMARCO IIIII IGHTS ft SHEET 2 OF 2 MODEL AVIATION horns avoid contact rudder fin-rudder assembly completed have full travel latter influenced conventional Use small plastic necessarily covered stage now shape inboard part eleva hinges slipped pre-cut slots cor- set up fuselage Make provision tors sweep stabilizer rect midline points frame glued foot spar rudder post spar practice Wellesley does minimum epoxy Check secur- spar standing glued onto small need much application rudder normal ity pulling gently hinge after block rudder course has move flight since ailerons epoxy has cured may next freely double arms horns must work model ailerons coupled day trick fitting stabilizer eleva tors fuselage cut away lead ing edge spar sufficiently enable maneuvered place Once thats done stand fuselage its nose floor steady glue main spar onto back rearmost bulkhead midpoint Theres very little room area work carefully accurately mak ing sure stabilizer dead square fuselage upright Once epoxy has set can build up broken lead ing edge short piece hard balsa glued bulkhead along side using filler piece necessary June 1988 57 Detail geodetic wing construction locations aileron flap servos Left Band-sawing soup can half soldering tin across flat bottom resulted nice looking custom fuel tank Right molding tools beds used make canopies see text details right aerodynamically clean Townend cowl rudder least time being may change separate controls later Once again rehearse final assembly glu ing making sure everything true accurate beforehand Replace stringers cut away earlier last end bay fuselage four shaped pieces / ply will provide access moving parts tail elevator rudder steerable tail wheel builder prefers stringers can left out first place since chance fuselage twist slight four small very light panels secured bulk heads very small self-tap screws spare weight put just enough no little visual embellish ment adds almost nothing weight quarter-section ping pong ball can fitted glued edge top half rear bulkhead elevator rudder controls closed-loop type Closed-loop systems work fine save weight used very lightweight fishing trace wire nylon cov ered should no 10-lb break ing strength assembling servo coupling up wires use miniature fishing tackle swivels servo end fish ing gear ferrules trap wire coupling up nip two wire cutters advantage swivels can ad just correct tension removing clevis worse twisting wire Allow enough slack wires can move sideways about midpoint end-to-end approximately ly tight wires bad servos steerable tail wheel 2 A-in dia light can find mounted made-up fork piano wireabout 16-gauge just stiff enough job Bind ends thin wire solder lightly slide piece aluminum tube glue epoxy Trim wire ends unit fits another tubeyou want nice sliding fitwhich epoxied built-up unit fuselage use balsa pieces give rigidity Test smooth movement Make up own crank horn carefully epoxy collar type used landing wheels Locked grub screw collar traps inner tube top projects above bear ing its horn connects arm rudder horn now have good steer able tail wheel adjustable cor rect tracking taking off taxiing also removable neces sary book neat taxiing straight down-the-dotted-line takeoffs add re alism model flight point backtrack front end fuselage few major jobs have done before proceeding other work make access cover removable b cut away part fu selage form air-gunner/radio mans position make pilots gunners canopies c cut away part fuse lage underside accommodate wing root double spars make hatch access cover remov able begin slipping razor blade tween centerline longerons break spot gluing will free cover nicely help retain its shape after removing cover fit small strut across back hatch fit front would prevent putting taking off cover cover off glue place double-thickness front bulkhead gluing bottom half hatch cover now has no forward movement Prevent side ways movement fitting little feet hatch cover slip inside longerons Make small adjustments hatch fits snugly position secure nylon bolts small platforms glued bulk heads inside fuselage can take cap tive nuts Recessed bolts help appearances Making pilots gunners canopies first think about awhile Since chance finding anything ready-made approximates right size shape nil have no op tion make yourself method chose heat-mold oven using molding tool finding way position clear acetate sheet securely newly found expertise area welcome Choose piece balsa big enough task Using drawings perhaps photographs carve sand pretend can opy will sit place fuselage inside part sits nicely either before after cutting away unwanted part fuselage begin carve shape canopy itself Balsa easy work type job since lot so-called carving reality coarse sanding rather actual shaping carvers tool solid balsa canopy appears just right eye make hole underpart crea tion accept handle choice used 4-in length -in doweling sure epoxy handle well has work canopy-and-handle unit serves molding tool Give good hard var nish Next make wood bed little bigger plan size tool sup ported feet high enough tool can go through matching hole mat tress leaving bit space say around can move tool out nicely take piece thin acetate sheet pin way around close hole push pins work fine Now comes fun part things 58 Model Aviation seems shame hide structural work like underneath covering Scale model full-size bombers have never known fOr having see-through wings Left Inside structure details cockpit hatch Right one-piece removable cockpit hatch give total access inner workings quiet kitchen mama out shop ping turn electric oven maxi mum heat oven has preheated high will go put bed metal tray oven leaving main door open inner glass door shut Watch what happens closely After about minute will see acetate beginning ripple meaning has softened heat Before collapses take out bed its tray grab tool pronto push firmly hole bed acetate has softened correctly tool will force accept its shape have lucky tool will now below mat tress level will soon cool its cool enough handle gently wiggle tool back forth until sepa rates acetate now has just shape intended Remove bed trim off frilly part skirt its set fitted fuselage Dont expect good results first time tempt heat-mold procedure its bit knack get right may need try before youre successful pilots canopy after final trimming nice fit can edge glued place Use short lengths masking tape hold position during setting gunners can opy prototype quite cleverly hinged its opened back half becomes windshield front part disappears inside fuselage Wellesley gunners kept canopy open al time being very little air turbulence generally warm air over Af rica Making models canopy swivel though would have complicated also impractical standpoint canopy will stiff using thin ac etate sheet permanently closed want realism swivel can opy no harm trying make gunners canopy permanently closed dont forget make up lifelike Lewis gun mount cut slot fixed metal com partment prototype rear canopy stowage gun task cutting away part fuse lage underside accommodate wing spars may done now left until after main part wing has con structed modelers discretion latter sequence may better either way method same After marking unwanted areasthe main spar thin rear sparcut out fretsaw knife building up ends big cutaway ply shape upper line cutout must coincide root wing ribs idea being fu selage fits onto wing other way around low-slung wing Vickers Wellesley Mk 1 Single-engined RAF tight bomber Model scale 1/10th based L2714 wartime identity letters AO-A No 223 Squadron RAE Dimensions Wingspan895 Wing area6298 sq ft 907 sq Wing sectionRAE32 Root chord15in Tip chord65in mci balsa tip Aspect ratio88 Fuselage length47in Wing dihedral21/20 Wing washoutouters30 Engine Enya 40-4C four-stroke 65cc 1/2 hp PropellerTornado reinforced nylon 121/2 x 5 Maximum rpm ground run 8500 Weights Fuselage tail unit motor fuel tank 43 oz Wing complete Rom-Air gear z Radio8 servos 6 channels 18 oz Bomb containers 4 oz FuelS fluid oz 4 oz Total 127 oz 7 lb 15 oz Nominal 2 oz ballast added damp down elevator response necessary Wing loading 8 lb wt 0 ozIsq ft Control throwsat trailing edge Elevator way Rudder 1 way Ailerons % up % down Flaps 11/2 full down approx 400 makes sense have supporting fuse lage times Dont dismayed small amount fuselage material re mains after the big cutout accommo dating wing has made hatch removed isnt cause con cern Suitably strengthened balsa planks favorite /64 ply side its frame fuselage tougher appearsready perils flying life crashes Once three jobs done rest fuselage construction basically con ventional spiced few specific adapta tions Two beechwood engine bearers 5 long in cross section slotted bulkheads also pro vide platform special fuel tank slightly offset make room engine servoa snug fit space available Its remarkable much design work has done certain areas ac commodate essential items Once engine bearers have fitted supplementary platforms radio gear ser vos etc can provided suit individual preference however recommend locate everything along lines Wellesley way youll least know everything works together logical fashion have good access parts space behind Enya 40-4C engine front bulkhead filled aluminum sheet cowl top half shaped paper pattern made ear lier screwed thick front bulkhead bottom half thin ply glued place pilots cockpit also part fuse lage construction After cutting out small cockpit area hatch cover make wooden replica windshield framework will probably have noticed order simulate solid front sec tion fuselage going back far cockpit balsa sticks have sandwiched between longerons stringers solid structure nicely sanded down sists making neat job cockpit sur round windshield frame made match drawing applies equally canopy minor trimming can June 1988 59 opy will needed before final test fit gluing Make certain however thing position before glue since af terwards youll have no further access cockpit except inside hatch removed simulated glass windshield panels made clear Plexiglass cut thick enough look good little care shaping panel before gluing will give realistic ap pearance Dont forget human eye tends look things some kind prior ity case Scale model its cockpit area attracts Wing Wellesley somewhat other airplane Im familiar constructing wing key crucial step model priority consideration get near geo detic construction prototype possi ble Almost important decision use well-proven system removable outer wings Boston radio setup dictated fact fuselage would sit wing just four bolts keep decided mount aileron flap servos together Rom-Air unit wing accommodating other components within fuselage makes preflight assemblyand post-flight disassemblyas simple foolproof possible As prototype starting point wing construction Y-shaped main spar design gives great strength its needed also accommodates landing gear nicely spar fashioned primarily top bottom sticks 14 x /16 spruce supplemented vertical grain balsa webs beefed up ply facing near wing roots before assembly spars very sturdy initial stages construction wing structure consists four master ply ribs distributed along inner wing assem bly shown drawings cut trimmed glued position Cut small narrow vertical slots outboard master ribs accommodating wing joiners refer plans Port star board wings constructed separately spruce spars projecting two inches beyond wing root ribs form struc ture center section Place wing skeleton wing plan drawing add balsa shaped leading edge spar rear spar latter built up -in strip balsa medium hard / ply facings Glue face separately ply being little oversize sand down afterwards will get light stiff spar trouble three spars glued integrally four master ribs before begin ning geodetic construction phase install balsa platforms flap aileron servos according drawing loca tion seems work out fine given de sign factors involved access panels very thin ply can secured very small self-tap screws suitably posi tioned small hardwood blocks no need quick access field Youre now ready turn two halfwing skeletons geodetic ones Using geodetic lines drawing roughly correspond prototype pre pare large quantity balsa sticks /16 soft sheet balsa about % wide Work ing along panel upper part frame cut fit sticks edge up herringbone pattern Run same pattern opposite direction cutting fitting sticks slot original ones creates arrangement diamond shapes squares somewhat resembling egg-crate An important point remember sticks positioned little higher wing contour Next make sanding stick Cover straight batten about 1 x 114 just little longer span half-wing sandpapercoarse side fine other halfwing lap begin sanding evenly across span structure working grain balsa sticks wherever possible Soon wing contours begin show have sanded down almost point touching master ribs use fine sandpaper finish off now have nicely shaped accurate tapered wing geodetic construction wing has strength spare could fact build acceptably strong using less material wing gener ously built still light needs hold back RAF 32 airfoil dupli cates the prototype par ticular airfoil must can substi tute nice-looking NACA biconvex version thats minimum two inches deep root chord Once first wing half looking good topside turn over create same airy basket weave contours underside Repeat process both sides other wing half routine beginning stale least know end product justifies means Wellesleys geodetic wing singularly twist-free light Now youre ready join wing pan els together first step make jigs support wings positioned drawings jigs must provide secure base give necessary 2 0 dihe dral prototype Equally important wing half must have precisely identical rigging angles fore aft pays work carefully accurately process wings carefully positioned over drawing ballasted necessary keep steady jigs angles correct whole business symmetri cal connect spruce spars project fuselage bay spruce cut shape like epoxy job its quick drying strong main spar connected repeat rear spar shaped front balsa spars have joined since main spar its doubled Y configuration provides strength enough Remove inner wing jigs beef up spar assembly vertical grain balsa join has taken place Check eye looks good Add three-ply faces spar make extremely serviceable cen ter section job have specific use well provide location brack ets accept nylon bolts attach fuselage wing Trial fit fuselage main part wing making usual adjustments alterations get right wing root ribs should bed nicely cutaway part fuselage wing must dead square fuselage centerline Continued page 138 60 Model Aviation Left The left wings outer panel Du-Sro quarter-turn latches secure inspection hatch twin belicrank elevator con nected servo cables Note lower edge rudder prolects forward way aft end tail wheel mount RC Helicopters/Jolly Continued page 135 possible go flybarless rotor head Ive flying GMPs heads flybarless several years now have excellent re suits modifying following way center yoke bandsawed off top machined portion head head assembled normally except damp ening must tight possible Rang ers ran GMP blades cut rotor diameter 58 blade ballasted center-of-gravity-corrected weight 190 grams Set up way ships superb fly Because use no mixer headjust two links direct swashplateI must cut down collective cyclic throws can quite excessive try heads flybarless just make sure dampening tight throws reduced head gets normal pitch changes youll really like flying flybarless Also 190-gram blades autorotations dream fact night flying Rangers just set down ground Being cute hit throttle hold pulled up collective head has much inertia Helicopter lifted higher head settled slowly back ground thought sure would run out blade speed bend bird up honest soft touchdown achieved So finished three Rangers time shipped ahead Globe AZ film ing would take place arrived two days later uncrated beauties finding minimal damage flicted air freight kind winced found Out would flying elevation 4000 ft Believe nothing gets director excited watch ing flying bomb winding up wanting lift off loaded 13 lb Cobra/ Rangers flew excellentlyeven altitude Franidy after building three Helicopters shipping location span month flying anticlimactic director picked out rock face locked off two high-speed cam eras panned two hit spot first time Id used real explosives like potassium nitrate primer cord weird have machine strike wall see flash observe total disintegration fuselage mechanics falling ground As loaded up after destroying third ship thinking grateful could de pend various model companies provide quality equipment capable doing job safely Anyway see Midnight Run look small part model aviation played give believable explosion New GMP machine coming Gorham Model Products has just given permission nounce new aerobatic Helicopter Leg end have flown prototype can tell Legend quite capable dar ing acrobatic maneuvers GMP will showing ship Toledo made show saw public display first time Anyway Legend still cooperative ef fort between Gorham Hirobo lot Gorham Legend features flybar less rotor head toothed-belt tail rotor drive ex tremely light weight John says de mostly two new space age materials called aluminum steel As soon can get some pictures Ill give preview BCNU Wellesley/Pelly-Fry Continued page 60 thin three-ply flaps split type hinged rear spar three points side flaps lightly braced fore aft along inside span make rigid Small cutaways under wing accommodate will give snug fit flap bellcrank fitted coincide servo location Using servo flap merely conveni ent rather technical necessity Its easy harmonize two servos adjust ments devises method constructing wing out ers same main inner wing ailerons having recessed hinge Set up port starboard wings spe cially made jigs making provision three degrees washout cut sand soft balsa wing tips shape glue place Finish covering outers nylon Before constructing ailerons provide access aileron bellcranks using Du Bro quarter-turn latches As shown drawing aileron consists basically number balsa ribs half-round lead ing edges aluminum tube spar located fat point rib section trailing FOAM WING CORES muuumuu.uuuuuumummu.uuuuuuuuuuu.uuummm U U I PRECISION MADE EXPANDED BEAD POLYSTYRENE REPLACEMENT 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Edition: Model Aviation - 1988/06
Page Numbers: 52, 53, 54, 55, 56, 57, 58, 59, 60, 138
EGroup Captain James Pelly-Fry Unique construction hallmark RAF bomber Brit ish used Ethiopia against Mussolini during early years WW II RC model design bit history come us men actually flew full-size plane action PART OF THE ROMANCE Scale aero modeling lies rescuing obscure forgot ten long-lost aircraft oblivion giving second life Searching details data necessary recreate old aircraft satisfying itself also adds another dimensionthe thrill huntto rewards pleasures acquiring expertise model builder Vickers Wellesley example just such long-forgotten discarded air craft long-range single-engine RAF bomber piloted World War II uncommonly efficient construction interesting history well worth know ing about brainchild Sir Barnes Wal lis Later war designed airships bouncing bomb destroyed huge dams Germany Wellesley flown successfully day night over Ethiopia against Mussolinis forces remarkable aircraft possessed ex ceptional load-carrying capabilityeven standard form could lift much its own weight 1938 three specially equipped Wellesleys flown nonstop over 48 hours Egypt Australiaa just-over-7 000-mile trip overturned world record distance held until Russia Fifty years ago 7000 unbroken miles fairly impressive achievement privileged command Wellesley squadrons having served second-in-command another squadron earlier war found air craft well exceeded expectations also piloted Douglas A20 Bob Wis cher has successfully built test flown Flying Scale model Wellesley comes second scaled-down version 52 Model Aviation Top extra wingspan lightweight construction enabled long-range RAF bomber lift much its own weight Above Its great thrill resurrect old de sign its particularly exciting bring plane back since no full-size version remains one-time military prototype person ally flew aviator As full-size aircraft both Douglas Wellesley did su perlative job very different wartime cir cumstances both have equal place sentiments salient characteristics Welles ley its very large wingspan 74 ft prototype good news model version use unique form air frame construction Barnes Wallis called geodetic consisting essentially double-spiral structure fuselage what might called basket weave wing stabilizer geodetic construc tion gave Wellesley exceptional light ness strength cardinal rule airplane design wing particular both extremely light very strong So far know single Wellesley specimen has recovered posterity left desert fate after Allied Forces moved Southern Europe Thus designing scaled-down version worthy aircraft researchthe aforementioned huntwould have lim ited whatever drawings sketches photographs could obtain Beaumont Avi ation London specializes keep ing records aviation data old maga zines books etc supplied some valuable material fortuitous coincidence also helped Matchbox Model Company recently produced 12-in-span stick together Wellesley kit ex Construction Once sufficient data work has collected piv otal step Scale design decide upon suitable scale choose hardware determined rest followsprob lems Wellesley after doing some figures back old enve lope chose Mo-scaleas RAF Boston counterpart A20 way Id get big wing keep wing loading down reasonable figuresthe perennial aim often eludes Scale modeler wingspan would 90 hoped get weight down around eight pounds power plant Enya 40-4C fourstroke seemed promising Id successfully fitted pair A20 RAF Bos ton case also happened have engines spare good friend Bud Voss uncertainty con cerned whether Enya sufficient power get big Wellesley airborne June 1988 53 cellent material supplied cooperative manufacturer got started proj ect Top particular model version plane once flew 223rd RAF Squadron Wellesley set distance world record 7000 continuous miles 1938 Above author rendition bombers piloted actually serving squadron commander during World War II scaled down one-tenth actual size big model flying safely Enya proved equal task landing gear supposed tail-down retractable job decided stay proven productthe excellent Rom-Air type As Boston gives creditable service very high wing loading sometimes occasions dramatic arrivals touchdown seemed natural choice use known entity Fuselage Fairly conventional construction used geodetic inner framework omitted sake weight-watch ing leaving four longerons stringers prototype establish correct oval shape cross section practice fabric covering used aft pilots cockpit course number flats sufficient number stringers employed maintain gen eral oval shape critical eye fuselage made up two halves using datum line straight along center line between top bottom halves method gives good foundation construction Mosquito employed es sentially same procedure dif ference being Mossie fuselage joined up top-and-bottom rather like chocolate Easter egg A-in-thick three-ply bulkheads TO I MAKE 2 MAKE RU 3RINS MA TRIM MAPLE MOTOR M U SHAPE BRA1 SCALE VOKES CARB FROM BALSA RLOCKS EV RUDDER SEEN PROM REAR H VB I/5 BALSA POST3 3/16 BALSA PIN 7 RUDDER F AME / I/I6 BALSA RI RINSEN LOCATION S TRIMTAB--H MUSC WRE TAILWHEE7 BRACEjXB BALSANOTSH BLOCKASEE TE XDETA LS S DA TALWHEEL 0IS345 constructed drawings appro priately slotted take north-south east-west longerons intermediate stringers completed cut across horizontal centerline using razor saw removes minimum timber useful number bulkhead go situated behind pi lots canopy has duplicated provide endpiece removal hatch reason make sure lower halves twin bulkhead glued gether top halves just lightly spot glued subsequent separa tion double lower bulkhead gives added strength rear spar wing passes through fuselage later Lay out full-size drawing top view fuselage building board steam shape first pair 4 x A-in spruce obechi sticks lie flat joined together 54 Model Aviation Using run-up table makes easier get everything assembled perform engine adjustments See text details making polystyrene external bomb containers Operating flaps slow big model down floating touchdowns add realism real beauty model lies just below its skin unique geodetic construction used designer Barnes Wallis give Wellesley lots strength lots weight Full-Size Plans Available. See Page 164 F WOOS .ASS B EPOXY ENGINE ORBOMB BOX IS MADE FROM FOAM BLOCK AND COVERED WITH FIBERGLASS EPOXYBOOS SUPPORT FRONT VIEW SCRAP WOOD SUPPORTS SAND TO AIRFOIL SHAPE SIDE VIEW USELAGE TOP VIEW NOTE FORMERS B THRO H ARE I/B PLYWOODTRIM AND NOTCH PER B F FIN CROSS IONREAR CLEAR PLASTIC CANOPY ENS SERB lIlY RUCTION FUSELAGE SIDE VIEW BOMB BOX y C I/4 PLY 1/B PLY -FORMERS-___ ---____________________ --I/G SO BALSA STRINGERS SPAR LINE I/4 I/lB BALSA LONG ERONS FIBERGLASS TOWNEND RING -x I/RPLYWOOO1/4 PLYWOOD / II LS MAPLE MOTOR MOUNTS K I FORWARD CLEAR PLASTIC CANOPY CLEARFUEL TANK PLASTICREMOVABLEVENTS WINDOWHATCH LINE C/771 E5OZFUELTANK SI/lB PLY FLAPS FLAP HORN ELEVATOR SERVO-i 2-I/ST INCIDENCE CS Y\ELAEJ--LSRyg I/32 PLY WHEEL COVERS WHEELS RCVR 5rNI II - ERY lID 3/B MAPLE MOTOR MOUNTS CLEAR PLASTIC WINDOW FIBERGLASS TOWNEND /1 oif i$ 40- 4 CYCLE ENGINE --c- I-S/B DIA SPINNER SHEET OF 2 MODEL AVIATION VICKERS WELLESLEY DESIGNED BY GRP CAPT JAMES PELLY FRY TRACING BY JOE DEMARCO RESERVED counterparts form completed longe rons Having pinned two sticks down securelyI pin either side through themtake top half-bulkhead hoop sequence glue its correct location Its best time hoop pretty unstable its small base halfbulkhead hoops glued position quick results used epoxy sup ported hoop anything handyso long hoop remained dead upright dur ing glue setting front bulkhead dou ble thickness ply strength Steam bend shape top longe rons again 1/4 x % Slot glue half-bulkhead hoops Slot glue %-in-sq balsa string ers fitting alternately avoid distor tion top half fuselage semicomplete sturdy enough handle re move building board An Enya 40 four-stroke provided plenty power model Note wire remote glow plug connector fuselage beams may look flimsy theyre plenty strong enough June 1988 55 drawing Place somewhere level weights bottom longerons pre serve true shape begin over again construction lower half fuselage constructing fuselage half keep mind its unnecessary stringers go way back theres much room anyway thin back end So its good idea shorten other suit eye case remove stringers last bay tail unit located Another im portant reminder Take great care second half fuselage duplicates first exactly possible particu larly true midpoint longerons must either glued fitted together inspection access hatch location Its impor tant take pains craftsmanship early stage project After checking two identical fu selage halves join together exactly apply glue along edgeswith important exception front half longe rons will glued just fitted gether what call touching fit around inspection hatch area youll separating hatch razor blade later Bring faces both glued fitted together secure along entire length springloaded office-type bulldog clipsvery handy grip firmly can fitted hand now have nicely shaped fairly stiff fuselage frame oval bulkheads have rigidity will ever needthe nylon covering add later will support moreand fuse lage length joined-up parts become good strong 14 x A-in-sq section forming master longerons along centerline Before setting aside masterpiece Im sure family friends will agree remove stringers last end bay tail unit will located will later replaced super-thin three-ply screwed place form ac cess hatches main hatch up front quick-remove can temporarily left spot glued place allow get used its new shape Empennage greatest need back end maximum lightness combined adequate strength flight ground handling fraction superfluous weight tail model roughly equivalent putting four times much nose Building light tail order exact weight penalty cannot stressed too strongly too often par ticularly Scale modeling basic layout prescribed external shape prototype builder finds after installing essential items like en gine fuel tank servo radio battery etc well up front still needs add much-dreaded ballast correct balance point Some Scale models need much two pounds lead squeezed nose offset tail weight thats terrible handicap Models short noses present biggest problems thus tend avoided Because requirement lightness materials stabilizer elevators fin rudder chosen great care kept judicious minimum wood primarily soft balsa plus small amount hard balsa little / super birchwood ply made Finlandthe latter strengthen both sides stabilizer main spar rudder post thin ply glued side separately keeping little oversize sanding down shape spars taper slighfly out tips theyre made up check twist during construction theyre weighted down during gluing allowed dry out well will remain straight true 2-in aluminum tube used connect elevators attach homemade control horns As fuselage make empen nage over drawings ensure accurate shape subtle curves give model its realism stabilizer distin guished its lattice-work geodetics elevators slightly off-center i/B PLY R-5~21/8 PLY EL I/B 1/5 BALSA 8-7 SMALL HINGES TO SUIT F SOFT BALSA BLOCK WING liPS HI LI STABILIZ GE IC LINES I/E S/lB BALSA-KEEP IT LIGHT-GEE TEST DETAILS BUILD FRAME FROM LAMINATES BALSA CROSSSECTION ALSALES R Left The air tank Rom-Air retracts servo operates valve inspection covers held place six self-tapping screws blisters necessary accommodate wheels Right Small inner covers wheel wells closed wheel itself upon retraction gear down weighted arms small doors keep open Plastic straps cover hole gear up 56 Model Aviation Full-Size Plans Available. See Page 164 R-6I/B PLYY SPAR IS /41/16 SPRUCE I/B PLYBOMB BOX LOCATIONWITH BALSA VERY SRAIN WEBS HORN MOUNTSEE TEST LEFT WINGWINS JOINT -LINE PLYAILERONR-I HORNB-S N-SILERO N-B-SERV -R -N C --ROM-AI RETRAC/ CB-BASEPLA/ IN / APBEPUBOS P0AERV L SR ROD AILERONS ARE BUILT UP SPARREARWITH BMSA RIBS SEE TEXT PLYSPAR DIHEDRAL 5-1/5 2FLAPS ARE I/IN PLY UNDER WINS5/16 PLY PLY RIBSEOOETIC LINES I/IN SEEP BY S/B WIDE BALSA SECTION ROOT CHORDSEE TEXT FOR CONSTRUCTIONR-2% SIB BALSA LE TAPEREDI/B PLY -RIGHT WING B-S AlONB-SR R ERV -A- SERVO FLAP AILERON HORN VICKERS WELLESLEY PLY HORN I161JNT DESIGNED BY GRP CAPT JAMES PELLY FRY BALSA YE STOCK0IS54BBTRACING BY JOE DEMARCO IIIII IGHTS ft SHEET 2 OF 2 MODEL AVIATION horns avoid contact rudder fin-rudder assembly completed have full travel latter influenced conventional Use small plastic necessarily covered stage now shape inboard part eleva hinges slipped pre-cut slots cor- set up fuselage Make provision tors sweep stabilizer rect midline points frame glued foot spar rudder post spar practice Wellesley does minimum epoxy Check secur- spar standing glued onto small need much application rudder normal ity pulling gently hinge after block rudder course has move flight since ailerons epoxy has cured may next freely double arms horns must work model ailerons coupled day trick fitting stabilizer eleva tors fuselage cut away lead ing edge spar sufficiently enable maneuvered place Once thats done stand fuselage its nose floor steady glue main spar onto back rearmost bulkhead midpoint Theres very little room area work carefully accurately mak ing sure stabilizer dead square fuselage upright Once epoxy has set can build up broken lead ing edge short piece hard balsa glued bulkhead along side using filler piece necessary June 1988 57 Detail geodetic wing construction locations aileron flap servos Left Band-sawing soup can half soldering tin across flat bottom resulted nice looking custom fuel tank Right molding tools beds used make canopies see text details right aerodynamically clean Townend cowl rudder least time being may change separate controls later Once again rehearse final assembly glu ing making sure everything true accurate beforehand Replace stringers cut away earlier last end bay fuselage four shaped pieces / ply will provide access moving parts tail elevator rudder steerable tail wheel builder prefers stringers can left out first place since chance fuselage twist slight four small very light panels secured bulk heads very small self-tap screws spare weight put just enough no little visual embellish ment adds almost nothing weight quarter-section ping pong ball can fitted glued edge top half rear bulkhead elevator rudder controls closed-loop type Closed-loop systems work fine save weight used very lightweight fishing trace wire nylon cov ered should no 10-lb break ing strength assembling servo coupling up wires use miniature fishing tackle swivels servo end fish ing gear ferrules trap wire coupling up nip two wire cutters advantage swivels can ad just correct tension removing clevis worse twisting wire Allow enough slack wires can move sideways about midpoint end-to-end approximately ly tight wires bad servos steerable tail wheel 2 A-in dia light can find mounted made-up fork piano wireabout 16-gauge just stiff enough job Bind ends thin wire solder lightly slide piece aluminum tube glue epoxy Trim wire ends unit fits another tubeyou want nice sliding fitwhich epoxied built-up unit fuselage use balsa pieces give rigidity Test smooth movement Make up own crank horn carefully epoxy collar type used landing wheels Locked grub screw collar traps inner tube top projects above bear ing its horn connects arm rudder horn now have good steer able tail wheel adjustable cor rect tracking taking off taxiing also removable neces sary book neat taxiing straight down-the-dotted-line takeoffs add re alism model flight point backtrack front end fuselage few major jobs have done before proceeding other work make access cover removable b cut away part fu selage form air-gunner/radio mans position make pilots gunners canopies c cut away part fuse lage underside accommodate wing root double spars make hatch access cover remov able begin slipping razor blade tween centerline longerons break spot gluing will free cover nicely help retain its shape after removing cover fit small strut across back hatch fit front would prevent putting taking off cover cover off glue place double-thickness front bulkhead gluing bottom half hatch cover now has no forward movement Prevent side ways movement fitting little feet hatch cover slip inside longerons Make small adjustments hatch fits snugly position secure nylon bolts small platforms glued bulk heads inside fuselage can take cap tive nuts Recessed bolts help appearances Making pilots gunners canopies first think about awhile Since chance finding anything ready-made approximates right size shape nil have no op tion make yourself method chose heat-mold oven using molding tool finding way position clear acetate sheet securely newly found expertise area welcome Choose piece balsa big enough task Using drawings perhaps photographs carve sand pretend can opy will sit place fuselage inside part sits nicely either before after cutting away unwanted part fuselage begin carve shape canopy itself Balsa easy work type job since lot so-called carving reality coarse sanding rather actual shaping carvers tool solid balsa canopy appears just right eye make hole underpart crea tion accept handle choice used 4-in length -in doweling sure epoxy handle well has work canopy-and-handle unit serves molding tool Give good hard var nish Next make wood bed little bigger plan size tool sup ported feet high enough tool can go through matching hole mat tress leaving bit space say around can move tool out nicely take piece thin acetate sheet pin way around close hole push pins work fine Now comes fun part things 58 Model Aviation seems shame hide structural work like underneath covering Scale model full-size bombers have never known fOr having see-through wings Left Inside structure details cockpit hatch Right one-piece removable cockpit hatch give total access inner workings quiet kitchen mama out shop ping turn electric oven maxi mum heat oven has preheated high will go put bed metal tray oven leaving main door open inner glass door shut Watch what happens closely After about minute will see acetate beginning ripple meaning has softened heat Before collapses take out bed its tray grab tool pronto push firmly hole bed acetate has softened correctly tool will force accept its shape have lucky tool will now below mat tress level will soon cool its cool enough handle gently wiggle tool back forth until sepa rates acetate now has just shape intended Remove bed trim off frilly part skirt its set fitted fuselage Dont expect good results first time tempt heat-mold procedure its bit knack get right may need try before youre successful pilots canopy after final trimming nice fit can edge glued place Use short lengths masking tape hold position during setting gunners can opy prototype quite cleverly hinged its opened back half becomes windshield front part disappears inside fuselage Wellesley gunners kept canopy open al time being very little air turbulence generally warm air over Af rica Making models canopy swivel though would have complicated also impractical standpoint canopy will stiff using thin ac etate sheet permanently closed want realism swivel can opy no harm trying make gunners canopy permanently closed dont forget make up lifelike Lewis gun mount cut slot fixed metal com partment prototype rear canopy stowage gun task cutting away part fuse lage underside accommodate wing spars may done now left until after main part wing has con structed modelers discretion latter sequence may better either way method same After marking unwanted areasthe main spar thin rear sparcut out fretsaw knife building up ends big cutaway ply shape upper line cutout must coincide root wing ribs idea being fu selage fits onto wing other way around low-slung wing Vickers Wellesley Mk 1 Single-engined RAF tight bomber Model scale 1/10th based L2714 wartime identity letters AO-A No 223 Squadron RAE Dimensions Wingspan895 Wing area6298 sq ft 907 sq Wing sectionRAE32 Root chord15in Tip chord65in mci balsa tip Aspect ratio88 Fuselage length47in Wing dihedral21/20 Wing washoutouters30 Engine Enya 40-4C four-stroke 65cc 1/2 hp PropellerTornado reinforced nylon 121/2 x 5 Maximum rpm ground run 8500 Weights Fuselage tail unit motor fuel tank 43 oz Wing complete Rom-Air gear z Radio8 servos 6 channels 18 oz Bomb containers 4 oz FuelS fluid oz 4 oz Total 127 oz 7 lb 15 oz Nominal 2 oz ballast added damp down elevator response necessary Wing loading 8 lb wt 0 ozIsq ft Control throwsat trailing edge Elevator way Rudder 1 way Ailerons % up % down Flaps 11/2 full down approx 400 makes sense have supporting fuse lage times Dont dismayed small amount fuselage material re mains after the big cutout accommo dating wing has made hatch removed isnt cause con cern Suitably strengthened balsa planks favorite /64 ply side its frame fuselage tougher appearsready perils flying life crashes Once three jobs done rest fuselage construction basically con ventional spiced few specific adapta tions Two beechwood engine bearers 5 long in cross section slotted bulkheads also pro vide platform special fuel tank slightly offset make room engine servoa snug fit space available Its remarkable much design work has done certain areas ac commodate essential items Once engine bearers have fitted supplementary platforms radio gear ser vos etc can provided suit individual preference however recommend locate everything along lines Wellesley way youll least know everything works together logical fashion have good access parts space behind Enya 40-4C engine front bulkhead filled aluminum sheet cowl top half shaped paper pattern made ear lier screwed thick front bulkhead bottom half thin ply glued place pilots cockpit also part fuse lage construction After cutting out small cockpit area hatch cover make wooden replica windshield framework will probably have noticed order simulate solid front sec tion fuselage going back far cockpit balsa sticks have sandwiched between longerons stringers solid structure nicely sanded down sists making neat job cockpit sur round windshield frame made match drawing applies equally canopy minor trimming can June 1988 59 opy will needed before final test fit gluing Make certain however thing position before glue since af terwards youll have no further access cockpit except inside hatch removed simulated glass windshield panels made clear Plexiglass cut thick enough look good little care shaping panel before gluing will give realistic ap pearance Dont forget human eye tends look things some kind prior ity case Scale model its cockpit area attracts Wing Wellesley somewhat other airplane Im familiar constructing wing key crucial step model priority consideration get near geo detic construction prototype possi ble Almost important decision use well-proven system removable outer wings Boston radio setup dictated fact fuselage would sit wing just four bolts keep decided mount aileron flap servos together Rom-Air unit wing accommodating other components within fuselage makes preflight assemblyand post-flight disassemblyas simple foolproof possible As prototype starting point wing construction Y-shaped main spar design gives great strength its needed also accommodates landing gear nicely spar fashioned primarily top bottom sticks 14 x /16 spruce supplemented vertical grain balsa webs beefed up ply facing near wing roots before assembly spars very sturdy initial stages construction wing structure consists four master ply ribs distributed along inner wing assem bly shown drawings cut trimmed glued position Cut small narrow vertical slots outboard master ribs accommodating wing joiners refer plans Port star board wings constructed separately spruce spars projecting two inches beyond wing root ribs form struc ture center section Place wing skeleton wing plan drawing add balsa shaped leading edge spar rear spar latter built up -in strip balsa medium hard / ply facings Glue face separately ply being little oversize sand down afterwards will get light stiff spar trouble three spars glued integrally four master ribs before begin ning geodetic construction phase install balsa platforms flap aileron servos according drawing loca tion seems work out fine given de sign factors involved access panels very thin ply can secured very small self-tap screws suitably posi tioned small hardwood blocks no need quick access field Youre now ready turn two halfwing skeletons geodetic ones Using geodetic lines drawing roughly correspond prototype pre pare large quantity balsa sticks /16 soft sheet balsa about % wide Work ing along panel upper part frame cut fit sticks edge up herringbone pattern Run same pattern opposite direction cutting fitting sticks slot original ones creates arrangement diamond shapes squares somewhat resembling egg-crate An important point remember sticks positioned little higher wing contour Next make sanding stick Cover straight batten about 1 x 114 just little longer span half-wing sandpapercoarse side fine other halfwing lap begin sanding evenly across span structure working grain balsa sticks wherever possible Soon wing contours begin show have sanded down almost point touching master ribs use fine sandpaper finish off now have nicely shaped accurate tapered wing geodetic construction wing has strength spare could fact build acceptably strong using less material wing gener ously built still light needs hold back RAF 32 airfoil dupli cates the prototype par ticular airfoil must can substi tute nice-looking NACA biconvex version thats minimum two inches deep root chord Once first wing half looking good topside turn over create same airy basket weave contours underside Repeat process both sides other wing half routine beginning stale least know end product justifies means Wellesleys geodetic wing singularly twist-free light Now youre ready join wing pan els together first step make jigs support wings positioned drawings jigs must provide secure base give necessary 2 0 dihe dral prototype Equally important wing half must have precisely identical rigging angles fore aft pays work carefully accurately process wings carefully positioned over drawing ballasted necessary keep steady jigs angles correct whole business symmetri cal connect spruce spars project fuselage bay spruce cut shape like epoxy job its quick drying strong main spar connected repeat rear spar shaped front balsa spars have joined since main spar its doubled Y configuration provides strength enough Remove inner wing jigs beef up spar assembly vertical grain balsa join has taken place Check eye looks good Add three-ply faces spar make extremely serviceable cen ter section job have specific use well provide location brack ets accept nylon bolts attach fuselage wing Trial fit fuselage main part wing making usual adjustments alterations get right wing root ribs should bed nicely cutaway part fuselage wing must dead square fuselage centerline Continued page 138 60 Model Aviation Left The left wings outer panel Du-Sro quarter-turn latches secure inspection hatch twin belicrank elevator con nected servo cables Note lower edge rudder prolects forward way aft end tail wheel mount RC Helicopters/Jolly Continued page 135 possible go flybarless rotor head Ive flying GMPs heads flybarless several years now have excellent re suits modifying following way center yoke bandsawed off top machined portion head head assembled normally except damp ening must tight possible Rang ers ran GMP blades cut rotor diameter 58 blade ballasted center-of-gravity-corrected weight 190 grams Set up way ships superb fly Because use no mixer headjust two links direct swashplateI must cut down collective cyclic throws can quite excessive try heads flybarless just make sure dampening tight throws reduced head gets normal pitch changes youll really like flying flybarless Also 190-gram blades autorotations dream fact night flying Rangers just set down ground Being cute hit throttle hold pulled up collective head has much inertia Helicopter lifted higher head settled slowly back ground thought sure would run out blade speed bend bird up honest soft touchdown achieved So finished three Rangers time shipped ahead Globe AZ film ing would take place arrived two days later uncrated beauties finding minimal damage flicted air freight kind winced found Out would flying elevation 4000 ft Believe nothing gets director excited watch ing flying bomb winding up wanting lift off loaded 13 lb Cobra/ Rangers flew excellentlyeven altitude Franidy after building three Helicopters shipping location span month flying anticlimactic director picked out rock face locked off two high-speed cam eras panned two hit spot first time Id used real explosives like potassium nitrate primer cord weird have machine strike wall see flash observe total disintegration fuselage mechanics falling ground As loaded up after destroying third ship thinking grateful could de pend various model companies provide quality equipment capable doing job safely Anyway see Midnight Run look small part model aviation played give believable explosion New GMP machine coming Gorham Model Products has just given permission nounce new aerobatic Helicopter Leg end have flown prototype can tell Legend quite capable dar ing acrobatic maneuvers GMP will showing ship Toledo made show saw public display first time Anyway Legend still cooperative ef fort between Gorham Hirobo lot Gorham Legend features flybar less rotor head toothed-belt tail rotor drive ex tremely light weight John says de mostly two new space age materials called aluminum steel As soon can get some pictures Ill give preview BCNU Wellesley/Pelly-Fry Continued page 60 thin three-ply flaps split type hinged rear spar three points side flaps lightly braced fore aft along inside span make rigid Small cutaways under wing accommodate will give snug fit flap bellcrank fitted coincide servo location Using servo flap merely conveni ent rather technical necessity Its easy harmonize two servos adjust ments devises method constructing wing out ers same main inner wing ailerons having recessed hinge Set up port starboard wings spe cially made jigs making provision three degrees washout cut sand soft balsa wing tips shape glue place Finish covering outers nylon Before constructing ailerons provide access aileron bellcranks using Du Bro quarter-turn latches As shown drawing aileron consists basically number balsa ribs half-round lead ing edges aluminum tube spar located fat point rib section trailing FOAM WING CORES muuumuu.uuuuuumummu.uuuuuuuuuuu.uuummm U U I PRECISION MADE EXPANDED BEAD POLYSTYRENE REPLACEMENT 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Edition: Model Aviation - 1988/06
Page Numbers: 52, 53, 54, 55, 56, 57, 58, 59, 60, 138
EGroup Captain James Pelly-Fry Unique construction hallmark RAF bomber Brit ish used Ethiopia against Mussolini during early years WW II RC model design bit history come us men actually flew full-size plane action PART OF THE ROMANCE Scale aero modeling lies rescuing obscure forgot ten long-lost aircraft oblivion giving second life Searching details data necessary recreate old aircraft satisfying itself also adds another dimensionthe thrill huntto rewards pleasures acquiring expertise model builder Vickers Wellesley example just such long-forgotten discarded air craft long-range single-engine RAF bomber piloted World War II uncommonly efficient construction interesting history well worth know ing about brainchild Sir Barnes Wal lis Later war designed airships bouncing bomb destroyed huge dams Germany Wellesley flown successfully day night over Ethiopia against Mussolinis forces remarkable aircraft possessed ex ceptional load-carrying capabilityeven standard form could lift much its own weight 1938 three specially equipped Wellesleys flown nonstop over 48 hours Egypt Australiaa just-over-7 000-mile trip overturned world record distance held until Russia Fifty years ago 7000 unbroken miles fairly impressive achievement privileged command Wellesley squadrons having served second-in-command another squadron earlier war found air craft well exceeded expectations also piloted Douglas A20 Bob Wis cher has successfully built test flown Flying Scale model Wellesley comes second scaled-down version 52 Model Aviation Top extra wingspan lightweight construction enabled long-range RAF bomber lift much its own weight Above Its great thrill resurrect old de sign its particularly exciting bring plane back since no full-size version remains one-time military prototype person ally flew aviator As full-size aircraft both Douglas Wellesley did su perlative job very different wartime cir cumstances both have equal place sentiments salient characteristics Welles ley its very large wingspan 74 ft prototype good news model version use unique form air frame construction Barnes Wallis called geodetic consisting essentially double-spiral structure fuselage what might called basket weave wing stabilizer geodetic construc tion gave Wellesley exceptional light ness strength cardinal rule airplane design wing particular both extremely light very strong So far know single Wellesley specimen has recovered posterity left desert fate after Allied Forces moved Southern Europe Thus designing scaled-down version worthy aircraft researchthe aforementioned huntwould have lim ited whatever drawings sketches photographs could obtain Beaumont Avi ation London specializes keep ing records aviation data old maga zines books etc supplied some valuable material fortuitous coincidence also helped Matchbox Model Company recently produced 12-in-span stick together Wellesley kit ex Construction Once sufficient data work has collected piv otal step Scale design decide upon suitable scale choose hardware determined rest followsprob lems Wellesley after doing some figures back old enve lope chose Mo-scaleas RAF Boston counterpart A20 way Id get big wing keep wing loading down reasonable figuresthe perennial aim often eludes Scale modeler wingspan would 90 hoped get weight down around eight pounds power plant Enya 40-4C fourstroke seemed promising Id successfully fitted pair A20 RAF Bos ton case also happened have engines spare good friend Bud Voss uncertainty con cerned whether Enya sufficient power get big Wellesley airborne June 1988 53 cellent material supplied cooperative manufacturer got started proj ect Top particular model version plane once flew 223rd RAF Squadron Wellesley set distance world record 7000 continuous miles 1938 Above author rendition bombers piloted actually serving squadron commander during World War II scaled down one-tenth actual size big model flying safely Enya proved equal task landing gear supposed tail-down retractable job decided stay proven productthe excellent Rom-Air type As Boston gives creditable service very high wing loading sometimes occasions dramatic arrivals touchdown seemed natural choice use known entity Fuselage Fairly conventional construction used geodetic inner framework omitted sake weight-watch ing leaving four longerons stringers prototype establish correct oval shape cross section practice fabric covering used aft pilots cockpit course number flats sufficient number stringers employed maintain gen eral oval shape critical eye fuselage made up two halves using datum line straight along center line between top bottom halves method gives good foundation construction Mosquito employed es sentially same procedure dif ference being Mossie fuselage joined up top-and-bottom rather like chocolate Easter egg A-in-thick three-ply bulkheads TO I MAKE 2 MAKE RU 3RINS MA TRIM MAPLE MOTOR M U SHAPE BRA1 SCALE VOKES CARB FROM BALSA RLOCKS EV RUDDER SEEN PROM REAR H VB I/5 BALSA POST3 3/16 BALSA PIN 7 RUDDER F AME / I/I6 BALSA RI RINSEN LOCATION S TRIMTAB--H MUSC WRE TAILWHEE7 BRACEjXB BALSANOTSH BLOCKASEE TE XDETA LS S DA TALWHEEL 0IS345 constructed drawings appro priately slotted take north-south east-west longerons intermediate stringers completed cut across horizontal centerline using razor saw removes minimum timber useful number bulkhead go situated behind pi lots canopy has duplicated provide endpiece removal hatch reason make sure lower halves twin bulkhead glued gether top halves just lightly spot glued subsequent separa tion double lower bulkhead gives added strength rear spar wing passes through fuselage later Lay out full-size drawing top view fuselage building board steam shape first pair 4 x A-in spruce obechi sticks lie flat joined together 54 Model Aviation Using run-up table makes easier get everything assembled perform engine adjustments See text details making polystyrene external bomb containers Operating flaps slow big model down floating touchdowns add realism real beauty model lies just below its skin unique geodetic construction used designer Barnes Wallis give Wellesley lots strength lots weight Full-Size Plans Available. See Page 164 F WOOS .ASS B EPOXY ENGINE ORBOMB BOX IS MADE FROM FOAM BLOCK AND COVERED WITH FIBERGLASS EPOXYBOOS SUPPORT FRONT VIEW SCRAP WOOD SUPPORTS SAND TO AIRFOIL SHAPE SIDE VIEW USELAGE TOP VIEW NOTE FORMERS B THRO H ARE I/B PLYWOODTRIM AND NOTCH PER B F FIN CROSS IONREAR CLEAR PLASTIC CANOPY ENS SERB lIlY RUCTION FUSELAGE SIDE VIEW BOMB BOX y C I/4 PLY 1/B PLY -FORMERS-___ ---____________________ --I/G SO BALSA STRINGERS SPAR LINE I/4 I/lB BALSA LONG ERONS FIBERGLASS TOWNEND RING -x I/RPLYWOOO1/4 PLYWOOD / II LS MAPLE MOTOR MOUNTS K I FORWARD CLEAR PLASTIC CANOPY CLEARFUEL TANK PLASTICREMOVABLEVENTS WINDOWHATCH LINE C/771 E5OZFUELTANK SI/lB PLY FLAPS FLAP HORN ELEVATOR SERVO-i 2-I/ST INCIDENCE CS Y\ELAEJ--LSRyg I/32 PLY WHEEL COVERS WHEELS RCVR 5rNI II - ERY lID 3/B MAPLE MOTOR MOUNTS CLEAR PLASTIC WINDOW FIBERGLASS TOWNEND /1 oif i$ 40- 4 CYCLE ENGINE --c- I-S/B DIA SPINNER SHEET OF 2 MODEL AVIATION VICKERS WELLESLEY DESIGNED BY GRP CAPT JAMES PELLY FRY TRACING BY JOE DEMARCO RESERVED counterparts form completed longe rons Having pinned two sticks down securelyI pin either side through themtake top half-bulkhead hoop sequence glue its correct location Its best time hoop pretty unstable its small base halfbulkhead hoops glued position quick results used epoxy sup ported hoop anything handyso long hoop remained dead upright dur ing glue setting front bulkhead dou ble thickness ply strength Steam bend shape top longe rons again 1/4 x % Slot glue half-bulkhead hoops Slot glue %-in-sq balsa string ers fitting alternately avoid distor tion top half fuselage semicomplete sturdy enough handle re move building board An Enya 40 four-stroke provided plenty power model Note wire remote glow plug connector fuselage beams may look flimsy theyre plenty strong enough June 1988 55 drawing Place somewhere level weights bottom longerons pre serve true shape begin over again construction lower half fuselage constructing fuselage half keep mind its unnecessary stringers go way back theres much room anyway thin back end So its good idea shorten other suit eye case remove stringers last bay tail unit located Another im portant reminder Take great care second half fuselage duplicates first exactly possible particu larly true midpoint longerons must either glued fitted together inspection access hatch location Its impor tant take pains craftsmanship early stage project After checking two identical fu selage halves join together exactly apply glue along edgeswith important exception front half longe rons will glued just fitted gether what call touching fit around inspection hatch area youll separating hatch razor blade later Bring faces both glued fitted together secure along entire length springloaded office-type bulldog clipsvery handy grip firmly can fitted hand now have nicely shaped fairly stiff fuselage frame oval bulkheads have rigidity will ever needthe nylon covering add later will support moreand fuse lage length joined-up parts become good strong 14 x A-in-sq section forming master longerons along centerline Before setting aside masterpiece Im sure family friends will agree remove stringers last end bay tail unit will located will later replaced super-thin three-ply screwed place form ac cess hatches main hatch up front quick-remove can temporarily left spot glued place allow get used its new shape Empennage greatest need back end maximum lightness combined adequate strength flight ground handling fraction superfluous weight tail model roughly equivalent putting four times much nose Building light tail order exact weight penalty cannot stressed too strongly too often par ticularly Scale modeling basic layout prescribed external shape prototype builder finds after installing essential items like en gine fuel tank servo radio battery etc well up front still needs add much-dreaded ballast correct balance point Some Scale models need much two pounds lead squeezed nose offset tail weight thats terrible handicap Models short noses present biggest problems thus tend avoided Because requirement lightness materials stabilizer elevators fin rudder chosen great care kept judicious minimum wood primarily soft balsa plus small amount hard balsa little / super birchwood ply made Finlandthe latter strengthen both sides stabilizer main spar rudder post thin ply glued side separately keeping little oversize sanding down shape spars taper slighfly out tips theyre made up check twist during construction theyre weighted down during gluing allowed dry out well will remain straight true 2-in aluminum tube used connect elevators attach homemade control horns As fuselage make empen nage over drawings ensure accurate shape subtle curves give model its realism stabilizer distin guished its lattice-work geodetics elevators slightly off-center i/B PLY R-5~21/8 PLY EL I/B 1/5 BALSA 8-7 SMALL HINGES TO SUIT F SOFT BALSA BLOCK WING liPS HI LI STABILIZ GE IC LINES I/E S/lB BALSA-KEEP IT LIGHT-GEE TEST DETAILS BUILD FRAME FROM LAMINATES BALSA CROSSSECTION ALSALES R Left The air tank Rom-Air retracts servo operates valve inspection covers held place six self-tapping screws blisters necessary accommodate wheels Right Small inner covers wheel wells closed wheel itself upon retraction gear down weighted arms small doors keep open Plastic straps cover hole gear up 56 Model Aviation Full-Size Plans Available. See Page 164 R-6I/B PLYY SPAR IS /41/16 SPRUCE I/B PLYBOMB BOX LOCATIONWITH BALSA VERY SRAIN WEBS HORN MOUNTSEE TEST LEFT WINGWINS JOINT -LINE PLYAILERONR-I HORNB-S N-SILERO N-B-SERV -R -N C --ROM-AI RETRAC/ CB-BASEPLA/ IN / APBEPUBOS P0AERV L SR ROD AILERONS ARE BUILT UP SPARREARWITH BMSA RIBS SEE TEXT PLYSPAR DIHEDRAL 5-1/5 2FLAPS ARE I/IN PLY UNDER WINS5/16 PLY PLY RIBSEOOETIC LINES I/IN SEEP BY S/B WIDE BALSA SECTION ROOT CHORDSEE TEXT FOR CONSTRUCTIONR-2% SIB BALSA LE TAPEREDI/B PLY -RIGHT WING B-S AlONB-SR R ERV -A- SERVO FLAP AILERON HORN VICKERS WELLESLEY PLY HORN I161JNT DESIGNED BY GRP CAPT JAMES PELLY FRY BALSA YE STOCK0IS54BBTRACING BY JOE DEMARCO IIIII IGHTS ft SHEET 2 OF 2 MODEL AVIATION horns avoid contact rudder fin-rudder assembly completed have full travel latter influenced conventional Use small plastic necessarily covered stage now shape inboard part eleva hinges slipped pre-cut slots cor- set up fuselage Make provision tors sweep stabilizer rect midline points frame glued foot spar rudder post spar practice Wellesley does minimum epoxy Check secur- spar standing glued onto small need much application rudder normal ity pulling gently hinge after block rudder course has move flight since ailerons epoxy has cured may next freely double arms horns must work model ailerons coupled day trick fitting stabilizer eleva tors fuselage cut away lead ing edge spar sufficiently enable maneuvered place Once thats done stand fuselage its nose floor steady glue main spar onto back rearmost bulkhead midpoint Theres very little room area work carefully accurately mak ing sure stabilizer dead square fuselage upright Once epoxy has set can build up broken lead ing edge short piece hard balsa glued bulkhead along side using filler piece necessary June 1988 57 Detail geodetic wing construction locations aileron flap servos Left Band-sawing soup can half soldering tin across flat bottom resulted nice looking custom fuel tank Right molding tools beds used make canopies see text details right aerodynamically clean Townend cowl rudder least time being may change separate controls later Once again rehearse final assembly glu ing making sure everything true accurate beforehand Replace stringers cut away earlier last end bay fuselage four shaped pieces / ply will provide access moving parts tail elevator rudder steerable tail wheel builder prefers stringers can left out first place since chance fuselage twist slight four small very light panels secured bulk heads very small self-tap screws spare weight put just enough no little visual embellish ment adds almost nothing weight quarter-section ping pong ball can fitted glued edge top half rear bulkhead elevator rudder controls closed-loop type Closed-loop systems work fine save weight used very lightweight fishing trace wire nylon cov ered should no 10-lb break ing strength assembling servo coupling up wires use miniature fishing tackle swivels servo end fish ing gear ferrules trap wire coupling up nip two wire cutters advantage swivels can ad just correct tension removing clevis worse twisting wire Allow enough slack wires can move sideways about midpoint end-to-end approximately ly tight wires bad servos steerable tail wheel 2 A-in dia light can find mounted made-up fork piano wireabout 16-gauge just stiff enough job Bind ends thin wire solder lightly slide piece aluminum tube glue epoxy Trim wire ends unit fits another tubeyou want nice sliding fitwhich epoxied built-up unit fuselage use balsa pieces give rigidity Test smooth movement Make up own crank horn carefully epoxy collar type used landing wheels Locked grub screw collar traps inner tube top projects above bear ing its horn connects arm rudder horn now have good steer able tail wheel adjustable cor rect tracking taking off taxiing also removable neces sary book neat taxiing straight down-the-dotted-line takeoffs add re alism model flight point backtrack front end fuselage few major jobs have done before proceeding other work make access cover removable b cut away part fu selage form air-gunner/radio mans position make pilots gunners canopies c cut away part fuse lage underside accommodate wing root double spars make hatch access cover remov able begin slipping razor blade tween centerline longerons break spot gluing will free cover nicely help retain its shape after removing cover fit small strut across back hatch fit front would prevent putting taking off cover cover off glue place double-thickness front bulkhead gluing bottom half hatch cover now has no forward movement Prevent side ways movement fitting little feet hatch cover slip inside longerons Make small adjustments hatch fits snugly position secure nylon bolts small platforms glued bulk heads inside fuselage can take cap tive nuts Recessed bolts help appearances Making pilots gunners canopies first think about awhile Since chance finding anything ready-made approximates right size shape nil have no op tion make yourself method chose heat-mold oven using molding tool finding way position clear acetate sheet securely newly found expertise area welcome Choose piece balsa big enough task Using drawings perhaps photographs carve sand pretend can opy will sit place fuselage inside part sits nicely either before after cutting away unwanted part fuselage begin carve shape canopy itself Balsa easy work type job since lot so-called carving reality coarse sanding rather actual shaping carvers tool solid balsa canopy appears just right eye make hole underpart crea tion accept handle choice used 4-in length -in doweling sure epoxy handle well has work canopy-and-handle unit serves molding tool Give good hard var nish Next make wood bed little bigger plan size tool sup ported feet high enough tool can go through matching hole mat tress leaving bit space say around can move tool out nicely take piece thin acetate sheet pin way around close hole push pins work fine Now comes fun part things 58 Model Aviation seems shame hide structural work like underneath covering Scale model full-size bombers have never known fOr having see-through wings Left Inside structure details cockpit hatch Right one-piece removable cockpit hatch give total access inner workings quiet kitchen mama out shop ping turn electric oven maxi mum heat oven has preheated high will go put bed metal tray oven leaving main door open inner glass door shut Watch what happens closely After about minute will see acetate beginning ripple meaning has softened heat Before collapses take out bed its tray grab tool pronto push firmly hole bed acetate has softened correctly tool will force accept its shape have lucky tool will now below mat tress level will soon cool its cool enough handle gently wiggle tool back forth until sepa rates acetate now has just shape intended Remove bed trim off frilly part skirt its set fitted fuselage Dont expect good results first time tempt heat-mold procedure its bit knack get right may need try before youre successful pilots canopy after final trimming nice fit can edge glued place Use short lengths masking tape hold position during setting gunners can opy prototype quite cleverly hinged its opened back half becomes windshield front part disappears inside fuselage Wellesley gunners kept canopy open al time being very little air turbulence generally warm air over Af rica Making models canopy swivel though would have complicated also impractical standpoint canopy will stiff using thin ac etate sheet permanently closed want realism swivel can opy no harm trying make gunners canopy permanently closed dont forget make up lifelike Lewis gun mount cut slot fixed metal com partment prototype rear canopy stowage gun task cutting away part fuse lage underside accommodate wing spars may done now left until after main part wing has con structed modelers discretion latter sequence may better either way method same After marking unwanted areasthe main spar thin rear sparcut out fretsaw knife building up ends big cutaway ply shape upper line cutout must coincide root wing ribs idea being fu selage fits onto wing other way around low-slung wing Vickers Wellesley Mk 1 Single-engined RAF tight bomber Model scale 1/10th based L2714 wartime identity letters AO-A No 223 Squadron RAE Dimensions Wingspan895 Wing area6298 sq ft 907 sq Wing sectionRAE32 Root chord15in Tip chord65in mci balsa tip Aspect ratio88 Fuselage length47in Wing dihedral21/20 Wing washoutouters30 Engine Enya 40-4C four-stroke 65cc 1/2 hp PropellerTornado reinforced nylon 121/2 x 5 Maximum rpm ground run 8500 Weights Fuselage tail unit motor fuel tank 43 oz Wing complete Rom-Air gear z Radio8 servos 6 channels 18 oz Bomb containers 4 oz FuelS fluid oz 4 oz Total 127 oz 7 lb 15 oz Nominal 2 oz ballast added damp down elevator response necessary Wing loading 8 lb wt 0 ozIsq ft Control throwsat trailing edge Elevator way Rudder 1 way Ailerons % up % down Flaps 11/2 full down approx 400 makes sense have supporting fuse lage times Dont dismayed small amount fuselage material re mains after the big cutout accommo dating wing has made hatch removed isnt cause con cern Suitably strengthened balsa planks favorite /64 ply side its frame fuselage tougher appearsready perils flying life crashes Once three jobs done rest fuselage construction basically con ventional spiced few specific adapta tions Two beechwood engine bearers 5 long in cross section slotted bulkheads also pro vide platform special fuel tank slightly offset make room engine servoa snug fit space available Its remarkable much design work has done certain areas ac commodate essential items Once engine bearers have fitted supplementary platforms radio gear ser vos etc can provided suit individual preference however recommend locate everything along lines Wellesley way youll least know everything works together logical fashion have good access parts space behind Enya 40-4C engine front bulkhead filled aluminum sheet cowl top half shaped paper pattern made ear lier screwed thick front bulkhead bottom half thin ply glued place pilots cockpit also part fuse lage construction After cutting out small cockpit area hatch cover make wooden replica windshield framework will probably have noticed order simulate solid front sec tion fuselage going back far cockpit balsa sticks have sandwiched between longerons stringers solid structure nicely sanded down sists making neat job cockpit sur round windshield frame made match drawing applies equally canopy minor trimming can June 1988 59 opy will needed before final test fit gluing Make certain however thing position before glue since af terwards youll have no further access cockpit except inside hatch removed simulated glass windshield panels made clear Plexiglass cut thick enough look good little care shaping panel before gluing will give realistic ap pearance Dont forget human eye tends look things some kind prior ity case Scale model its cockpit area attracts Wing Wellesley somewhat other airplane Im familiar constructing wing key crucial step model priority consideration get near geo detic construction prototype possi ble Almost important decision use well-proven system removable outer wings Boston radio setup dictated fact fuselage would sit wing just four bolts keep decided mount aileron flap servos together Rom-Air unit wing accommodating other components within fuselage makes preflight assemblyand post-flight disassemblyas simple foolproof possible As prototype starting point wing construction Y-shaped main spar design gives great strength its needed also accommodates landing gear nicely spar fashioned primarily top bottom sticks 14 x /16 spruce supplemented vertical grain balsa webs beefed up ply facing near wing roots before assembly spars very sturdy initial stages construction wing structure consists four master ply ribs distributed along inner wing assem bly shown drawings cut trimmed glued position Cut small narrow vertical slots outboard master ribs accommodating wing joiners refer plans Port star board wings constructed separately spruce spars projecting two inches beyond wing root ribs form struc ture center section Place wing skeleton wing plan drawing add balsa shaped leading edge spar rear spar latter built up -in strip balsa medium hard / ply facings Glue face separately ply being little oversize sand down afterwards will get light stiff spar trouble three spars glued integrally four master ribs before begin ning geodetic construction phase install balsa platforms flap aileron servos according drawing loca tion seems work out fine given de sign factors involved access panels very thin ply can secured very small self-tap screws suitably posi tioned small hardwood blocks no need quick access field Youre now ready turn two halfwing skeletons geodetic ones Using geodetic lines drawing roughly correspond prototype pre pare large quantity balsa sticks /16 soft sheet balsa about % wide Work ing along panel upper part frame cut fit sticks edge up herringbone pattern Run same pattern opposite direction cutting fitting sticks slot original ones creates arrangement diamond shapes squares somewhat resembling egg-crate An important point remember sticks positioned little higher wing contour Next make sanding stick Cover straight batten about 1 x 114 just little longer span half-wing sandpapercoarse side fine other halfwing lap begin sanding evenly across span structure working grain balsa sticks wherever possible Soon wing contours begin show have sanded down almost point touching master ribs use fine sandpaper finish off now have nicely shaped accurate tapered wing geodetic construction wing has strength spare could fact build acceptably strong using less material wing gener ously built still light needs hold back RAF 32 airfoil dupli cates the prototype par ticular airfoil must can substi tute nice-looking NACA biconvex version thats minimum two inches deep root chord Once first wing half looking good topside turn over create same airy basket weave contours underside Repeat process both sides other wing half routine beginning stale least know end product justifies means Wellesleys geodetic wing singularly twist-free light Now youre ready join wing pan els together first step make jigs support wings positioned drawings jigs must provide secure base give necessary 2 0 dihe dral prototype Equally important wing half must have precisely identical rigging angles fore aft pays work carefully accurately process wings carefully positioned over drawing ballasted necessary keep steady jigs angles correct whole business symmetri cal connect spruce spars project fuselage bay spruce cut shape like epoxy job its quick drying strong main spar connected repeat rear spar shaped front balsa spars have joined since main spar its doubled Y configuration provides strength enough Remove inner wing jigs beef up spar assembly vertical grain balsa join has taken place Check eye looks good Add three-ply faces spar make extremely serviceable cen ter section job have specific use well provide location brack ets accept nylon bolts attach fuselage wing Trial fit fuselage main part wing making usual adjustments alterations get right wing root ribs should bed nicely cutaway part fuselage wing must dead square fuselage centerline Continued page 138 60 Model Aviation Left The left wings outer panel Du-Sro quarter-turn latches secure inspection hatch twin belicrank elevator con nected servo cables Note lower edge rudder prolects forward way aft end tail wheel mount RC Helicopters/Jolly Continued page 135 possible go flybarless rotor head Ive flying GMPs heads flybarless several years now have excellent re suits modifying following way center yoke bandsawed off top machined portion head head assembled normally except damp ening must tight possible Rang ers ran GMP blades cut rotor diameter 58 blade ballasted center-of-gravity-corrected weight 190 grams Set up way ships superb fly Because use no mixer headjust two links direct swashplateI must cut down collective cyclic throws can quite excessive try heads flybarless just make sure dampening tight throws reduced head gets normal pitch changes youll really like flying flybarless Also 190-gram blades autorotations dream fact night flying Rangers just set down ground Being cute hit throttle hold pulled up collective head has much inertia Helicopter lifted higher head settled slowly back ground thought sure would run out blade speed bend bird up honest soft touchdown achieved So finished three Rangers time shipped ahead Globe AZ film ing would take place arrived two days later uncrated beauties finding minimal damage flicted air freight kind winced found Out would flying elevation 4000 ft Believe nothing gets director excited watch ing flying bomb winding up wanting lift off loaded 13 lb Cobra/ Rangers flew excellentlyeven altitude Franidy after building three Helicopters shipping location span month flying anticlimactic director picked out rock face locked off two high-speed cam eras panned two hit spot first time Id used real explosives like potassium nitrate primer cord weird have machine strike wall see flash observe total disintegration fuselage mechanics falling ground As loaded up after destroying third ship thinking grateful could de pend various model companies provide quality equipment capable doing job safely Anyway see Midnight Run look small part model aviation played give believable explosion New GMP machine coming Gorham Model Products has just given permission nounce new aerobatic Helicopter Leg end have flown prototype can tell Legend quite capable dar ing acrobatic maneuvers GMP will showing ship Toledo made show saw public display first time Anyway Legend still cooperative ef fort between Gorham Hirobo lot Gorham Legend features flybar less rotor head toothed-belt tail rotor drive ex tremely light weight John says de mostly two new space age materials called aluminum steel As soon can get some pictures Ill give preview BCNU Wellesley/Pelly-Fry Continued page 60 thin three-ply flaps split type hinged rear spar three points side flaps lightly braced fore aft along inside span make rigid Small cutaways under wing accommodate will give snug fit flap bellcrank fitted coincide servo location Using servo flap merely conveni ent rather technical necessity Its easy harmonize two servos adjust ments devises method constructing wing out ers same main inner wing ailerons having recessed hinge Set up port starboard wings spe cially made jigs making provision three degrees washout cut sand soft balsa wing tips shape glue place Finish covering outers nylon Before constructing ailerons provide access aileron bellcranks using Du Bro quarter-turn latches As shown drawing aileron consists basically number balsa ribs half-round lead ing edges aluminum tube spar located fat point rib section trailing FOAM WING CORES muuumuu.uuuuuumummu.uuuuuuuuuuu.uuummm U U I PRECISION MADE EXPANDED BEAD POLYSTYRENE REPLACEMENT 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Edition: Model Aviation - 1988/06
Page Numbers: 52, 53, 54, 55, 56, 57, 58, 59, 60, 138
EGroup Captain James Pelly-Fry Unique construction hallmark RAF bomber Brit ish used Ethiopia against Mussolini during early years WW II RC model design bit history come us men actually flew full-size plane action PART OF THE ROMANCE Scale aero modeling lies rescuing obscure forgot ten long-lost aircraft oblivion giving second life Searching details data necessary recreate old aircraft satisfying itself also adds another dimensionthe thrill huntto rewards pleasures acquiring expertise model builder Vickers Wellesley example just such long-forgotten discarded air craft long-range single-engine RAF bomber piloted World War II uncommonly efficient construction interesting history well worth know ing about brainchild Sir Barnes Wal lis Later war designed airships bouncing bomb destroyed huge dams Germany Wellesley flown successfully day night over Ethiopia against Mussolinis forces remarkable aircraft possessed ex ceptional load-carrying capabilityeven standard form could lift much its own weight 1938 three specially equipped Wellesleys flown nonstop over 48 hours Egypt Australiaa just-over-7 000-mile trip overturned world record distance held until Russia Fifty years ago 7000 unbroken miles fairly impressive achievement privileged command Wellesley squadrons having served second-in-command another squadron earlier war found air craft well exceeded expectations also piloted Douglas A20 Bob Wis cher has successfully built test flown Flying Scale model Wellesley comes second scaled-down version 52 Model Aviation Top extra wingspan lightweight construction enabled long-range RAF bomber lift much its own weight Above Its great thrill resurrect old de sign its particularly exciting bring plane back since no full-size version remains one-time military prototype person ally flew aviator As full-size aircraft both Douglas Wellesley did su perlative job very different wartime cir cumstances both have equal place sentiments salient characteristics Welles ley its very large wingspan 74 ft prototype good news model version use unique form air frame construction Barnes Wallis called geodetic consisting essentially double-spiral structure fuselage what might called basket weave wing stabilizer geodetic construc tion gave Wellesley exceptional light ness strength cardinal rule airplane design wing particular both extremely light very strong So far know single Wellesley specimen has recovered posterity left desert fate after Allied Forces moved Southern Europe Thus designing scaled-down version worthy aircraft researchthe aforementioned huntwould have lim ited whatever drawings sketches photographs could obtain Beaumont Avi ation London specializes keep ing records aviation data old maga zines books etc supplied some valuable material fortuitous coincidence also helped Matchbox Model Company recently produced 12-in-span stick together Wellesley kit ex Construction Once sufficient data work has collected piv otal step Scale design decide upon suitable scale choose hardware determined rest followsprob lems Wellesley after doing some figures back old enve lope chose Mo-scaleas RAF Boston counterpart A20 way Id get big wing keep wing loading down reasonable figuresthe perennial aim often eludes Scale modeler wingspan would 90 hoped get weight down around eight pounds power plant Enya 40-4C fourstroke seemed promising Id successfully fitted pair A20 RAF Bos ton case also happened have engines spare good friend Bud Voss uncertainty con cerned whether Enya sufficient power get big Wellesley airborne June 1988 53 cellent material supplied cooperative manufacturer got started proj ect Top particular model version plane once flew 223rd RAF Squadron Wellesley set distance world record 7000 continuous miles 1938 Above author rendition bombers piloted actually serving squadron commander during World War II scaled down one-tenth actual size big model flying safely Enya proved equal task landing gear supposed tail-down retractable job decided stay proven productthe excellent Rom-Air type As Boston gives creditable service very high wing loading sometimes occasions dramatic arrivals touchdown seemed natural choice use known entity Fuselage Fairly conventional construction used geodetic inner framework omitted sake weight-watch ing leaving four longerons stringers prototype establish correct oval shape cross section practice fabric covering used aft pilots cockpit course number flats sufficient number stringers employed maintain gen eral oval shape critical eye fuselage made up two halves using datum line straight along center line between top bottom halves method gives good foundation construction Mosquito employed es sentially same procedure dif ference being Mossie fuselage joined up top-and-bottom rather like chocolate Easter egg A-in-thick three-ply bulkheads TO I MAKE 2 MAKE RU 3RINS MA TRIM MAPLE MOTOR M U SHAPE BRA1 SCALE VOKES CARB FROM BALSA RLOCKS EV RUDDER SEEN PROM REAR H VB I/5 BALSA POST3 3/16 BALSA PIN 7 RUDDER F AME / I/I6 BALSA RI RINSEN LOCATION S TRIMTAB--H MUSC WRE TAILWHEE7 BRACEjXB BALSANOTSH BLOCKASEE TE XDETA LS S DA TALWHEEL 0IS345 constructed drawings appro priately slotted take north-south east-west longerons intermediate stringers completed cut across horizontal centerline using razor saw removes minimum timber useful number bulkhead go situated behind pi lots canopy has duplicated provide endpiece removal hatch reason make sure lower halves twin bulkhead glued gether top halves just lightly spot glued subsequent separa tion double lower bulkhead gives added strength rear spar wing passes through fuselage later Lay out full-size drawing top view fuselage building board steam shape first pair 4 x A-in spruce obechi sticks lie flat joined together 54 Model Aviation Using run-up table makes easier get everything assembled perform engine adjustments See text details making polystyrene external bomb containers Operating flaps slow big model down floating touchdowns add realism real beauty model lies just below its skin unique geodetic construction used designer Barnes Wallis give Wellesley lots strength lots weight Full-Size Plans Available. See Page 164 F WOOS .ASS B EPOXY ENGINE ORBOMB BOX IS MADE FROM FOAM BLOCK AND COVERED WITH FIBERGLASS EPOXYBOOS SUPPORT FRONT VIEW SCRAP WOOD SUPPORTS SAND TO AIRFOIL SHAPE SIDE VIEW USELAGE TOP VIEW NOTE FORMERS B THRO H ARE I/B PLYWOODTRIM AND NOTCH PER B F FIN CROSS IONREAR CLEAR PLASTIC CANOPY ENS SERB lIlY RUCTION FUSELAGE SIDE VIEW BOMB BOX y C I/4 PLY 1/B PLY -FORMERS-___ ---____________________ --I/G SO BALSA STRINGERS SPAR LINE I/4 I/lB BALSA LONG ERONS FIBERGLASS TOWNEND RING -x I/RPLYWOOO1/4 PLYWOOD / II LS MAPLE MOTOR MOUNTS K I FORWARD CLEAR PLASTIC CANOPY CLEARFUEL TANK PLASTICREMOVABLEVENTS WINDOWHATCH LINE C/771 E5OZFUELTANK SI/lB PLY FLAPS FLAP HORN ELEVATOR SERVO-i 2-I/ST INCIDENCE CS Y\ELAEJ--LSRyg I/32 PLY WHEEL COVERS WHEELS RCVR 5rNI II - ERY lID 3/B MAPLE MOTOR MOUNTS CLEAR PLASTIC WINDOW FIBERGLASS TOWNEND /1 oif i$ 40- 4 CYCLE ENGINE --c- I-S/B DIA SPINNER SHEET OF 2 MODEL AVIATION VICKERS WELLESLEY DESIGNED BY GRP CAPT JAMES PELLY FRY TRACING BY JOE DEMARCO RESERVED counterparts form completed longe rons Having pinned two sticks down securelyI pin either side through themtake top half-bulkhead hoop sequence glue its correct location Its best time hoop pretty unstable its small base halfbulkhead hoops glued position quick results used epoxy sup ported hoop anything handyso long hoop remained dead upright dur ing glue setting front bulkhead dou ble thickness ply strength Steam bend shape top longe rons again 1/4 x % Slot glue half-bulkhead hoops Slot glue %-in-sq balsa string ers fitting alternately avoid distor tion top half fuselage semicomplete sturdy enough handle re move building board An Enya 40 four-stroke provided plenty power model Note wire remote glow plug connector fuselage beams may look flimsy theyre plenty strong enough June 1988 55 drawing Place somewhere level weights bottom longerons pre serve true shape begin over again construction lower half fuselage constructing fuselage half keep mind its unnecessary stringers go way back theres much room anyway thin back end So its good idea shorten other suit eye case remove stringers last bay tail unit located Another im portant reminder Take great care second half fuselage duplicates first exactly possible particu larly true midpoint longerons must either glued fitted together inspection access hatch location Its impor tant take pains craftsmanship early stage project After checking two identical fu selage halves join together exactly apply glue along edgeswith important exception front half longe rons will glued just fitted gether what call touching fit around inspection hatch area youll separating hatch razor blade later Bring faces both glued fitted together secure along entire length springloaded office-type bulldog clipsvery handy grip firmly can fitted hand now have nicely shaped fairly stiff fuselage frame oval bulkheads have rigidity will ever needthe nylon covering add later will support moreand fuse lage length joined-up parts become good strong 14 x A-in-sq section forming master longerons along centerline Before setting aside masterpiece Im sure family friends will agree remove stringers last end bay tail unit will located will later replaced super-thin three-ply screwed place form ac cess hatches main hatch up front quick-remove can temporarily left spot glued place allow get used its new shape Empennage greatest need back end maximum lightness combined adequate strength flight ground handling fraction superfluous weight tail model roughly equivalent putting four times much nose Building light tail order exact weight penalty cannot stressed too strongly too often par ticularly Scale modeling basic layout prescribed external shape prototype builder finds after installing essential items like en gine fuel tank servo radio battery etc well up front still needs add much-dreaded ballast correct balance point Some Scale models need much two pounds lead squeezed nose offset tail weight thats terrible handicap Models short noses present biggest problems thus tend avoided Because requirement lightness materials stabilizer elevators fin rudder chosen great care kept judicious minimum wood primarily soft balsa plus small amount hard balsa little / super birchwood ply made Finlandthe latter strengthen both sides stabilizer main spar rudder post thin ply glued side separately keeping little oversize sanding down shape spars taper slighfly out tips theyre made up check twist during construction theyre weighted down during gluing allowed dry out well will remain straight true 2-in aluminum tube used connect elevators attach homemade control horns As fuselage make empen nage over drawings ensure accurate shape subtle curves give model its realism stabilizer distin guished its lattice-work geodetics elevators slightly off-center i/B PLY R-5~21/8 PLY EL I/B 1/5 BALSA 8-7 SMALL HINGES TO SUIT F SOFT BALSA BLOCK WING liPS HI LI STABILIZ GE IC LINES I/E S/lB BALSA-KEEP IT LIGHT-GEE TEST DETAILS BUILD FRAME FROM LAMINATES BALSA CROSSSECTION ALSALES R Left The air tank Rom-Air retracts servo operates valve inspection covers held place six self-tapping screws blisters necessary accommodate wheels Right Small inner covers wheel wells closed wheel itself upon retraction gear down weighted arms small doors keep open Plastic straps cover hole gear up 56 Model Aviation Full-Size Plans Available. See Page 164 R-6I/B PLYY SPAR IS /41/16 SPRUCE I/B PLYBOMB BOX LOCATIONWITH BALSA VERY SRAIN WEBS HORN MOUNTSEE TEST LEFT WINGWINS JOINT -LINE PLYAILERONR-I HORNB-S N-SILERO N-B-SERV -R -N C --ROM-AI RETRAC/ CB-BASEPLA/ IN / APBEPUBOS P0AERV L SR ROD AILERONS ARE BUILT UP SPARREARWITH BMSA RIBS SEE TEXT PLYSPAR DIHEDRAL 5-1/5 2FLAPS ARE I/IN PLY UNDER WINS5/16 PLY PLY RIBSEOOETIC LINES I/IN SEEP BY S/B WIDE BALSA SECTION ROOT CHORDSEE TEXT FOR CONSTRUCTIONR-2% SIB BALSA LE TAPEREDI/B PLY -RIGHT WING B-S AlONB-SR R ERV -A- SERVO FLAP AILERON HORN VICKERS WELLESLEY PLY HORN I161JNT DESIGNED BY GRP CAPT JAMES PELLY FRY BALSA YE STOCK0IS54BBTRACING BY JOE DEMARCO IIIII IGHTS ft SHEET 2 OF 2 MODEL AVIATION horns avoid contact rudder fin-rudder assembly completed have full travel latter influenced conventional Use small plastic necessarily covered stage now shape inboard part eleva hinges slipped pre-cut slots cor- set up fuselage Make provision tors sweep stabilizer rect midline points frame glued foot spar rudder post spar practice Wellesley does minimum epoxy Check secur- spar standing glued onto small need much application rudder normal ity pulling gently hinge after block rudder course has move flight since ailerons epoxy has cured may next freely double arms horns must work model ailerons coupled day trick fitting stabilizer eleva tors fuselage cut away lead ing edge spar sufficiently enable maneuvered place Once thats done stand fuselage its nose floor steady glue main spar onto back rearmost bulkhead midpoint Theres very little room area work carefully accurately mak ing sure stabilizer dead square fuselage upright Once epoxy has set can build up broken lead ing edge short piece hard balsa glued bulkhead along side using filler piece necessary June 1988 57 Detail geodetic wing construction locations aileron flap servos Left Band-sawing soup can half soldering tin across flat bottom resulted nice looking custom fuel tank Right molding tools beds used make canopies see text details right aerodynamically clean Townend cowl rudder least time being may change separate controls later Once again rehearse final assembly glu ing making sure everything true accurate beforehand Replace stringers cut away earlier last end bay fuselage four shaped pieces / ply will provide access moving parts tail elevator rudder steerable tail wheel builder prefers stringers can left out first place since chance fuselage twist slight four small very light panels secured bulk heads very small self-tap screws spare weight put just enough no little visual embellish ment adds almost nothing weight quarter-section ping pong ball can fitted glued edge top half rear bulkhead elevator rudder controls closed-loop type Closed-loop systems work fine save weight used very lightweight fishing trace wire nylon cov ered should no 10-lb break ing strength assembling servo coupling up wires use miniature fishing tackle swivels servo end fish ing gear ferrules trap wire coupling up nip two wire cutters advantage swivels can ad just correct tension removing clevis worse twisting wire Allow enough slack wires can move sideways about midpoint end-to-end approximately ly tight wires bad servos steerable tail wheel 2 A-in dia light can find mounted made-up fork piano wireabout 16-gauge just stiff enough job Bind ends thin wire solder lightly slide piece aluminum tube glue epoxy Trim wire ends unit fits another tubeyou want nice sliding fitwhich epoxied built-up unit fuselage use balsa pieces give rigidity Test smooth movement Make up own crank horn carefully epoxy collar type used landing wheels Locked grub screw collar traps inner tube top projects above bear ing its horn connects arm rudder horn now have good steer able tail wheel adjustable cor rect tracking taking off taxiing also removable neces sary book neat taxiing straight down-the-dotted-line takeoffs add re alism model flight point backtrack front end fuselage few major jobs have done before proceeding other work make access cover removable b cut away part fu selage form air-gunner/radio mans position make pilots gunners canopies c cut away part fuse lage underside accommodate wing root double spars make hatch access cover remov able begin slipping razor blade tween centerline longerons break spot gluing will free cover nicely help retain its shape after removing cover fit small strut across back hatch fit front would prevent putting taking off cover cover off glue place double-thickness front bulkhead gluing bottom half hatch cover now has no forward movement Prevent side ways movement fitting little feet hatch cover slip inside longerons Make small adjustments hatch fits snugly position secure nylon bolts small platforms glued bulk heads inside fuselage can take cap tive nuts Recessed bolts help appearances Making pilots gunners canopies first think about awhile Since chance finding anything ready-made approximates right size shape nil have no op tion make yourself method chose heat-mold oven using molding tool finding way position clear acetate sheet securely newly found expertise area welcome Choose piece balsa big enough task Using drawings perhaps photographs carve sand pretend can opy will sit place fuselage inside part sits nicely either before after cutting away unwanted part fuselage begin carve shape canopy itself Balsa easy work type job since lot so-called carving reality coarse sanding rather actual shaping carvers tool solid balsa canopy appears just right eye make hole underpart crea tion accept handle choice used 4-in length -in doweling sure epoxy handle well has work canopy-and-handle unit serves molding tool Give good hard var nish Next make wood bed little bigger plan size tool sup ported feet high enough tool can go through matching hole mat tress leaving bit space say around can move tool out nicely take piece thin acetate sheet pin way around close hole push pins work fine Now comes fun part things 58 Model Aviation seems shame hide structural work like underneath covering Scale model full-size bombers have never known fOr having see-through wings Left Inside structure details cockpit hatch Right one-piece removable cockpit hatch give total access inner workings quiet kitchen mama out shop ping turn electric oven maxi mum heat oven has preheated high will go put bed metal tray oven leaving main door open inner glass door shut Watch what happens closely After about minute will see acetate beginning ripple meaning has softened heat Before collapses take out bed its tray grab tool pronto push firmly hole bed acetate has softened correctly tool will force accept its shape have lucky tool will now below mat tress level will soon cool its cool enough handle gently wiggle tool back forth until sepa rates acetate now has just shape intended Remove bed trim off frilly part skirt its set fitted fuselage Dont expect good results first time tempt heat-mold procedure its bit knack get right may need try before youre successful pilots canopy after final trimming nice fit can edge glued place Use short lengths masking tape hold position during setting gunners can opy prototype quite cleverly hinged its opened back half becomes windshield front part disappears inside fuselage Wellesley gunners kept canopy open al time being very little air turbulence generally warm air over Af rica Making models canopy swivel though would have complicated also impractical standpoint canopy will stiff using thin ac etate sheet permanently closed want realism swivel can opy no harm trying make gunners canopy permanently closed dont forget make up lifelike Lewis gun mount cut slot fixed metal com partment prototype rear canopy stowage gun task cutting away part fuse lage underside accommodate wing spars may done now left until after main part wing has con structed modelers discretion latter sequence may better either way method same After marking unwanted areasthe main spar thin rear sparcut out fretsaw knife building up ends big cutaway ply shape upper line cutout must coincide root wing ribs idea being fu selage fits onto wing other way around low-slung wing Vickers Wellesley Mk 1 Single-engined RAF tight bomber Model scale 1/10th based L2714 wartime identity letters AO-A No 223 Squadron RAE Dimensions Wingspan895 Wing area6298 sq ft 907 sq Wing sectionRAE32 Root chord15in Tip chord65in mci balsa tip Aspect ratio88 Fuselage length47in Wing dihedral21/20 Wing washoutouters30 Engine Enya 40-4C four-stroke 65cc 1/2 hp PropellerTornado reinforced nylon 121/2 x 5 Maximum rpm ground run 8500 Weights Fuselage tail unit motor fuel tank 43 oz Wing complete Rom-Air gear z Radio8 servos 6 channels 18 oz Bomb containers 4 oz FuelS fluid oz 4 oz Total 127 oz 7 lb 15 oz Nominal 2 oz ballast added damp down elevator response necessary Wing loading 8 lb wt 0 ozIsq ft Control throwsat trailing edge Elevator way Rudder 1 way Ailerons % up % down Flaps 11/2 full down approx 400 makes sense have supporting fuse lage times Dont dismayed small amount fuselage material re mains after the big cutout accommo dating wing has made hatch removed isnt cause con cern Suitably strengthened balsa planks favorite /64 ply side its frame fuselage tougher appearsready perils flying life crashes Once three jobs done rest fuselage construction basically con ventional spiced few specific adapta tions Two beechwood engine bearers 5 long in cross section slotted bulkheads also pro vide platform special fuel tank slightly offset make room engine servoa snug fit space available Its remarkable much design work has done certain areas ac commodate essential items Once engine bearers have fitted supplementary platforms radio gear ser vos etc can provided suit individual preference however recommend locate everything along lines Wellesley way youll least know everything works together logical fashion have good access parts space behind Enya 40-4C engine front bulkhead filled aluminum sheet cowl top half shaped paper pattern made ear lier screwed thick front bulkhead bottom half thin ply glued place pilots cockpit also part fuse lage construction After cutting out small cockpit area hatch cover make wooden replica windshield framework will probably have noticed order simulate solid front sec tion fuselage going back far cockpit balsa sticks have sandwiched between longerons stringers solid structure nicely sanded down sists making neat job cockpit sur round windshield frame made match drawing applies equally canopy minor trimming can June 1988 59 opy will needed before final test fit gluing Make certain however thing position before glue since af terwards youll have no further access cockpit except inside hatch removed simulated glass windshield panels made clear Plexiglass cut thick enough look good little care shaping panel before gluing will give realistic ap pearance Dont forget human eye tends look things some kind prior ity case Scale model its cockpit area attracts Wing Wellesley somewhat other airplane Im familiar constructing wing key crucial step model priority consideration get near geo detic construction prototype possi ble Almost important decision use well-proven system removable outer wings Boston radio setup dictated fact fuselage would sit wing just four bolts keep decided mount aileron flap servos together Rom-Air unit wing accommodating other components within fuselage makes preflight assemblyand post-flight disassemblyas simple foolproof possible As prototype starting point wing construction Y-shaped main spar design gives great strength its needed also accommodates landing gear nicely spar fashioned primarily top bottom sticks 14 x /16 spruce supplemented vertical grain balsa webs beefed up ply facing near wing roots before assembly spars very sturdy initial stages construction wing structure consists four master ply ribs distributed along inner wing assem bly shown drawings cut trimmed glued position Cut small narrow vertical slots outboard master ribs accommodating wing joiners refer plans Port star board wings constructed separately spruce spars projecting two inches beyond wing root ribs form struc ture center section Place wing skeleton wing plan drawing add balsa shaped leading edge spar rear spar latter built up -in strip balsa medium hard / ply facings Glue face separately ply being little oversize sand down afterwards will get light stiff spar trouble three spars glued integrally four master ribs before begin ning geodetic construction phase install balsa platforms flap aileron servos according drawing loca tion seems work out fine given de sign factors involved access panels very thin ply can secured very small self-tap screws suitably posi tioned small hardwood blocks no need quick access field Youre now ready turn two halfwing skeletons geodetic ones Using geodetic lines drawing roughly correspond prototype pre pare large quantity balsa sticks /16 soft sheet balsa about % wide Work ing along panel upper part frame cut fit sticks edge up herringbone pattern Run same pattern opposite direction cutting fitting sticks slot original ones creates arrangement diamond shapes squares somewhat resembling egg-crate An important point remember sticks positioned little higher wing contour Next make sanding stick Cover straight batten about 1 x 114 just little longer span half-wing sandpapercoarse side fine other halfwing lap begin sanding evenly across span structure working grain balsa sticks wherever possible Soon wing contours begin show have sanded down almost point touching master ribs use fine sandpaper finish off now have nicely shaped accurate tapered wing geodetic construction wing has strength spare could fact build acceptably strong using less material wing gener ously built still light needs hold back RAF 32 airfoil dupli cates the prototype par ticular airfoil must can substi tute nice-looking NACA biconvex version thats minimum two inches deep root chord Once first wing half looking good topside turn over create same airy basket weave contours underside Repeat process both sides other wing half routine beginning stale least know end product justifies means Wellesleys geodetic wing singularly twist-free light Now youre ready join wing pan els together first step make jigs support wings positioned drawings jigs must provide secure base give necessary 2 0 dihe dral prototype Equally important wing half must have precisely identical rigging angles fore aft pays work carefully accurately process wings carefully positioned over drawing ballasted necessary keep steady jigs angles correct whole business symmetri cal connect spruce spars project fuselage bay spruce cut shape like epoxy job its quick drying strong main spar connected repeat rear spar shaped front balsa spars have joined since main spar its doubled Y configuration provides strength enough Remove inner wing jigs beef up spar assembly vertical grain balsa join has taken place Check eye looks good Add three-ply faces spar make extremely serviceable cen ter section job have specific use well provide location brack ets accept nylon bolts attach fuselage wing Trial fit fuselage main part wing making usual adjustments alterations get right wing root ribs should bed nicely cutaway part fuselage wing must dead square fuselage centerline Continued page 138 60 Model Aviation Left The left wings outer panel Du-Sro quarter-turn latches secure inspection hatch twin belicrank elevator con nected servo cables Note lower edge rudder prolects forward way aft end tail wheel mount RC Helicopters/Jolly Continued page 135 possible go flybarless rotor head Ive flying GMPs heads flybarless several years now have excellent re suits modifying following way center yoke bandsawed off top machined portion head head assembled normally except damp ening must tight possible Rang ers ran GMP blades cut rotor diameter 58 blade ballasted center-of-gravity-corrected weight 190 grams Set up way ships superb fly Because use no mixer headjust two links direct swashplateI must cut down collective cyclic throws can quite excessive try heads flybarless just make sure dampening tight throws reduced head gets normal pitch changes youll really like flying flybarless Also 190-gram blades autorotations dream fact night flying Rangers just set down ground Being cute hit throttle hold pulled up collective head has much inertia Helicopter lifted higher head settled slowly back ground thought sure would run out blade speed bend bird up honest soft touchdown achieved So finished three Rangers time shipped ahead Globe AZ film ing would take place arrived two days later uncrated beauties finding minimal damage flicted air freight kind winced found Out would flying elevation 4000 ft Believe nothing gets director excited watch ing flying bomb winding up wanting lift off loaded 13 lb Cobra/ Rangers flew excellentlyeven altitude Franidy after building three Helicopters shipping location span month flying anticlimactic director picked out rock face locked off two high-speed cam eras panned two hit spot first time Id used real explosives like potassium nitrate primer cord weird have machine strike wall see flash observe total disintegration fuselage mechanics falling ground As loaded up after destroying third ship thinking grateful could de pend various model companies provide quality equipment capable doing job safely Anyway see Midnight Run look small part model aviation played give believable explosion New GMP machine coming Gorham Model Products has just given permission nounce new aerobatic Helicopter Leg end have flown prototype can tell Legend quite capable dar ing acrobatic maneuvers GMP will showing ship Toledo made show saw public display first time Anyway Legend still cooperative ef fort between Gorham Hirobo lot Gorham Legend features flybar less rotor head toothed-belt tail rotor drive ex tremely light weight John says de mostly two new space age materials called aluminum steel As soon can get some pictures Ill give preview BCNU Wellesley/Pelly-Fry Continued page 60 thin three-ply flaps split type hinged rear spar three points side flaps lightly braced fore aft along inside span make rigid Small cutaways under wing accommodate will give snug fit flap bellcrank fitted coincide servo location Using servo flap merely conveni ent rather technical necessity Its easy harmonize two servos adjust ments devises method constructing wing out ers same main inner wing ailerons having recessed hinge Set up port starboard wings spe cially made jigs making provision three degrees washout cut sand soft balsa wing tips shape glue place Finish covering outers nylon Before constructing ailerons provide access aileron bellcranks using Du Bro quarter-turn latches As shown drawing aileron consists basically number balsa ribs half-round lead ing edges aluminum tube spar located fat point rib section trailing FOAM WING CORES muuumuu.uuuuuumummu.uuuuuuuuuuu.uuummm U U I PRECISION MADE EXPANDED BEAD POLYSTYRENE REPLACEMENT 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Edition: Model Aviation - 1988/06
Page Numbers: 52, 53, 54, 55, 56, 57, 58, 59, 60, 138
EGroup Captain James Pelly-Fry Unique construction hallmark RAF bomber Brit ish used Ethiopia against Mussolini during early years WW II RC model design bit history come us men actually flew full-size plane action PART OF THE ROMANCE Scale aero modeling lies rescuing obscure forgot ten long-lost aircraft oblivion giving second life Searching details data necessary recreate old aircraft satisfying itself also adds another dimensionthe thrill huntto rewards pleasures acquiring expertise model builder Vickers Wellesley example just such long-forgotten discarded air craft long-range single-engine RAF bomber piloted World War II uncommonly efficient construction interesting history well worth know ing about brainchild Sir Barnes Wal lis Later war designed airships bouncing bomb destroyed huge dams Germany Wellesley flown successfully day night over Ethiopia against Mussolinis forces remarkable aircraft possessed ex ceptional load-carrying capabilityeven standard form could lift much its own weight 1938 three specially equipped Wellesleys flown nonstop over 48 hours Egypt Australiaa just-over-7 000-mile trip overturned world record distance held until Russia Fifty years ago 7000 unbroken miles fairly impressive achievement privileged command Wellesley squadrons having served second-in-command another squadron earlier war found air craft well exceeded expectations also piloted Douglas A20 Bob Wis cher has successfully built test flown Flying Scale model Wellesley comes second scaled-down version 52 Model Aviation Top extra wingspan lightweight construction enabled long-range RAF bomber lift much its own weight Above Its great thrill resurrect old de sign its particularly exciting bring plane back since no full-size version remains one-time military prototype person ally flew aviator As full-size aircraft both Douglas Wellesley did su perlative job very different wartime cir cumstances both have equal place sentiments salient characteristics Welles ley its very large wingspan 74 ft prototype good news model version use unique form air frame construction Barnes Wallis called geodetic consisting essentially double-spiral structure fuselage what might called basket weave wing stabilizer geodetic construc tion gave Wellesley exceptional light ness strength cardinal rule airplane design wing particular both extremely light very strong So far know single Wellesley specimen has recovered posterity left desert fate after Allied Forces moved Southern Europe Thus designing scaled-down version worthy aircraft researchthe aforementioned huntwould have lim ited whatever drawings sketches photographs could obtain Beaumont Avi ation London specializes keep ing records aviation data old maga zines books etc supplied some valuable material fortuitous coincidence also helped Matchbox Model Company recently produced 12-in-span stick together Wellesley kit ex Construction Once sufficient data work has collected piv otal step Scale design decide upon suitable scale choose hardware determined rest followsprob lems Wellesley after doing some figures back old enve lope chose Mo-scaleas RAF Boston counterpart A20 way Id get big wing keep wing loading down reasonable figuresthe perennial aim often eludes Scale modeler wingspan would 90 hoped get weight down around eight pounds power plant Enya 40-4C fourstroke seemed promising Id successfully fitted pair A20 RAF Bos ton case also happened have engines spare good friend Bud Voss uncertainty con cerned whether Enya sufficient power get big Wellesley airborne June 1988 53 cellent material supplied cooperative manufacturer got started proj ect Top particular model version plane once flew 223rd RAF Squadron Wellesley set distance world record 7000 continuous miles 1938 Above author rendition bombers piloted actually serving squadron commander during World War II scaled down one-tenth actual size big model flying safely Enya proved equal task landing gear supposed tail-down retractable job decided stay proven productthe excellent Rom-Air type As Boston gives creditable service very high wing loading sometimes occasions dramatic arrivals touchdown seemed natural choice use known entity Fuselage Fairly conventional construction used geodetic inner framework omitted sake weight-watch ing leaving four longerons stringers prototype establish correct oval shape cross section practice fabric covering used aft pilots cockpit course number flats sufficient number stringers employed maintain gen eral oval shape critical eye fuselage made up two halves using datum line straight along center line between top bottom halves method gives good foundation construction Mosquito employed es sentially same procedure dif ference being Mossie fuselage joined up top-and-bottom rather like chocolate Easter egg A-in-thick three-ply bulkheads TO I MAKE 2 MAKE RU 3RINS MA TRIM MAPLE MOTOR M U SHAPE BRA1 SCALE VOKES CARB FROM BALSA RLOCKS EV RUDDER SEEN PROM REAR H VB I/5 BALSA POST3 3/16 BALSA PIN 7 RUDDER F AME / I/I6 BALSA RI RINSEN LOCATION S TRIMTAB--H MUSC WRE TAILWHEE7 BRACEjXB BALSANOTSH BLOCKASEE TE XDETA LS S DA TALWHEEL 0IS345 constructed drawings appro priately slotted take north-south east-west longerons intermediate stringers completed cut across horizontal centerline using razor saw removes minimum timber useful number bulkhead go situated behind pi lots canopy has duplicated provide endpiece removal hatch reason make sure lower halves twin bulkhead glued gether top halves just lightly spot glued subsequent separa tion double lower bulkhead gives added strength rear spar wing passes through fuselage later Lay out full-size drawing top view fuselage building board steam shape first pair 4 x A-in spruce obechi sticks lie flat joined together 54 Model Aviation Using run-up table makes easier get everything assembled perform engine adjustments See text details making polystyrene external bomb containers Operating flaps slow big model down floating touchdowns add realism real beauty model lies just below its skin unique geodetic construction used designer Barnes Wallis give Wellesley lots strength lots weight Full-Size Plans Available. See Page 164 F WOOS .ASS B EPOXY ENGINE ORBOMB BOX IS MADE FROM FOAM BLOCK AND COVERED WITH FIBERGLASS EPOXYBOOS SUPPORT FRONT VIEW SCRAP WOOD SUPPORTS SAND TO AIRFOIL SHAPE SIDE VIEW USELAGE TOP VIEW NOTE FORMERS B THRO H ARE I/B PLYWOODTRIM AND NOTCH PER B F FIN CROSS IONREAR CLEAR PLASTIC CANOPY ENS SERB lIlY RUCTION FUSELAGE SIDE VIEW BOMB BOX y C I/4 PLY 1/B PLY -FORMERS-___ ---____________________ --I/G SO BALSA STRINGERS SPAR LINE I/4 I/lB BALSA LONG ERONS FIBERGLASS TOWNEND RING -x I/RPLYWOOO1/4 PLYWOOD / II LS MAPLE MOTOR MOUNTS K I FORWARD CLEAR PLASTIC CANOPY CLEARFUEL TANK PLASTICREMOVABLEVENTS WINDOWHATCH LINE C/771 E5OZFUELTANK SI/lB PLY FLAPS FLAP HORN ELEVATOR SERVO-i 2-I/ST INCIDENCE CS Y\ELAEJ--LSRyg I/32 PLY WHEEL COVERS WHEELS RCVR 5rNI II - ERY lID 3/B MAPLE MOTOR MOUNTS CLEAR PLASTIC WINDOW FIBERGLASS TOWNEND /1 oif i$ 40- 4 CYCLE ENGINE --c- I-S/B DIA SPINNER SHEET OF 2 MODEL AVIATION VICKERS WELLESLEY DESIGNED BY GRP CAPT JAMES PELLY FRY TRACING BY JOE DEMARCO RESERVED counterparts form completed longe rons Having pinned two sticks down securelyI pin either side through themtake top half-bulkhead hoop sequence glue its correct location Its best time hoop pretty unstable its small base halfbulkhead hoops glued position quick results used epoxy sup ported hoop anything handyso long hoop remained dead upright dur ing glue setting front bulkhead dou ble thickness ply strength Steam bend shape top longe rons again 1/4 x % Slot glue half-bulkhead hoops Slot glue %-in-sq balsa string ers fitting alternately avoid distor tion top half fuselage semicomplete sturdy enough handle re move building board An Enya 40 four-stroke provided plenty power model Note wire remote glow plug connector fuselage beams may look flimsy theyre plenty strong enough June 1988 55 drawing Place somewhere level weights bottom longerons pre serve true shape begin over again construction lower half fuselage constructing fuselage half keep mind its unnecessary stringers go way back theres much room anyway thin back end So its good idea shorten other suit eye case remove stringers last bay tail unit located Another im portant reminder Take great care second half fuselage duplicates first exactly possible particu larly true midpoint longerons must either glued fitted together inspection access hatch location Its impor tant take pains craftsmanship early stage project After checking two identical fu selage halves join together exactly apply glue along edgeswith important exception front half longe rons will glued just fitted gether what call touching fit around inspection hatch area youll separating hatch razor blade later Bring faces both glued fitted together secure along entire length springloaded office-type bulldog clipsvery handy grip firmly can fitted hand now have nicely shaped fairly stiff fuselage frame oval bulkheads have rigidity will ever needthe nylon covering add later will support moreand fuse lage length joined-up parts become good strong 14 x A-in-sq section forming master longerons along centerline Before setting aside masterpiece Im sure family friends will agree remove stringers last end bay tail unit will located will later replaced super-thin three-ply screwed place form ac cess hatches main hatch up front quick-remove can temporarily left spot glued place allow get used its new shape Empennage greatest need back end maximum lightness combined adequate strength flight ground handling fraction superfluous weight tail model roughly equivalent putting four times much nose Building light tail order exact weight penalty cannot stressed too strongly too often par ticularly Scale modeling basic layout prescribed external shape prototype builder finds after installing essential items like en gine fuel tank servo radio battery etc well up front still needs add much-dreaded ballast correct balance point Some Scale models need much two pounds lead squeezed nose offset tail weight thats terrible handicap Models short noses present biggest problems thus tend avoided Because requirement lightness materials stabilizer elevators fin rudder chosen great care kept judicious minimum wood primarily soft balsa plus small amount hard balsa little / super birchwood ply made Finlandthe latter strengthen both sides stabilizer main spar rudder post thin ply glued side separately keeping little oversize sanding down shape spars taper slighfly out tips theyre made up check twist during construction theyre weighted down during gluing allowed dry out well will remain straight true 2-in aluminum tube used connect elevators attach homemade control horns As fuselage make empen nage over drawings ensure accurate shape subtle curves give model its realism stabilizer distin guished its lattice-work geodetics elevators slightly off-center i/B PLY R-5~21/8 PLY EL I/B 1/5 BALSA 8-7 SMALL HINGES TO SUIT F SOFT BALSA BLOCK WING liPS HI LI STABILIZ GE IC LINES I/E S/lB BALSA-KEEP IT LIGHT-GEE TEST DETAILS BUILD FRAME FROM LAMINATES BALSA CROSSSECTION ALSALES R Left The air tank Rom-Air retracts servo operates valve inspection covers held place six self-tapping screws blisters necessary accommodate wheels Right Small inner covers wheel wells closed wheel itself upon retraction gear down weighted arms small doors keep open Plastic straps cover hole gear up 56 Model Aviation Full-Size Plans Available. See Page 164 R-6I/B PLYY SPAR IS /41/16 SPRUCE I/B PLYBOMB BOX LOCATIONWITH BALSA VERY SRAIN WEBS HORN MOUNTSEE TEST LEFT WINGWINS JOINT -LINE PLYAILERONR-I HORNB-S N-SILERO N-B-SERV -R -N C --ROM-AI RETRAC/ CB-BASEPLA/ IN / APBEPUBOS P0AERV L SR ROD AILERONS ARE BUILT UP SPARREARWITH BMSA RIBS SEE TEXT PLYSPAR DIHEDRAL 5-1/5 2FLAPS ARE I/IN PLY UNDER WINS5/16 PLY PLY RIBSEOOETIC LINES I/IN SEEP BY S/B WIDE BALSA SECTION ROOT CHORDSEE TEXT FOR CONSTRUCTIONR-2% SIB BALSA LE TAPEREDI/B PLY -RIGHT WING B-S AlONB-SR R ERV -A- SERVO FLAP AILERON HORN VICKERS WELLESLEY PLY HORN I161JNT DESIGNED BY GRP CAPT JAMES PELLY FRY BALSA YE STOCK0IS54BBTRACING BY JOE DEMARCO IIIII IGHTS ft SHEET 2 OF 2 MODEL AVIATION horns avoid contact rudder fin-rudder assembly completed have full travel latter influenced conventional Use small plastic necessarily covered stage now shape inboard part eleva hinges slipped pre-cut slots cor- set up fuselage Make provision tors sweep stabilizer rect midline points frame glued foot spar rudder post spar practice Wellesley does minimum epoxy Check secur- spar standing glued onto small need much application rudder normal ity pulling gently hinge after block rudder course has move flight since ailerons epoxy has cured may next freely double arms horns must work model ailerons coupled day trick fitting stabilizer eleva tors fuselage cut away lead ing edge spar sufficiently enable maneuvered place Once thats done stand fuselage its nose floor steady glue main spar onto back rearmost bulkhead midpoint Theres very little room area work carefully accurately mak ing sure stabilizer dead square fuselage upright Once epoxy has set can build up broken lead ing edge short piece hard balsa glued bulkhead along side using filler piece necessary June 1988 57 Detail geodetic wing construction locations aileron flap servos Left Band-sawing soup can half soldering tin across flat bottom resulted nice looking custom fuel tank Right molding tools beds used make canopies see text details right aerodynamically clean Townend cowl rudder least time being may change separate controls later Once again rehearse final assembly glu ing making sure everything true accurate beforehand Replace stringers cut away earlier last end bay fuselage four shaped pieces / ply will provide access moving parts tail elevator rudder steerable tail wheel builder prefers stringers can left out first place since chance fuselage twist slight four small very light panels secured bulk heads very small self-tap screws spare weight put just enough no little visual embellish ment adds almost nothing weight quarter-section ping pong ball can fitted glued edge top half rear bulkhead elevator rudder controls closed-loop type Closed-loop systems work fine save weight used very lightweight fishing trace wire nylon cov ered should no 10-lb break ing strength assembling servo coupling up wires use miniature fishing tackle swivels servo end fish ing gear ferrules trap wire coupling up nip two wire cutters advantage swivels can ad just correct tension removing clevis worse twisting wire Allow enough slack wires can move sideways about midpoint end-to-end approximately ly tight wires bad servos steerable tail wheel 2 A-in dia light can find mounted made-up fork piano wireabout 16-gauge just stiff enough job Bind ends thin wire solder lightly slide piece aluminum tube glue epoxy Trim wire ends unit fits another tubeyou want nice sliding fitwhich epoxied built-up unit fuselage use balsa pieces give rigidity Test smooth movement Make up own crank horn carefully epoxy collar type used landing wheels Locked grub screw collar traps inner tube top projects above bear ing its horn connects arm rudder horn now have good steer able tail wheel adjustable cor rect tracking taking off taxiing also removable neces sary book neat taxiing straight down-the-dotted-line takeoffs add re alism model flight point backtrack front end fuselage few major jobs have done before proceeding other work make access cover removable b cut away part fu selage form air-gunner/radio mans position make pilots gunners canopies c cut away part fuse lage underside accommodate wing root double spars make hatch access cover remov able begin slipping razor blade tween centerline longerons break spot gluing will free cover nicely help retain its shape after removing cover fit small strut across back hatch fit front would prevent putting taking off cover cover off glue place double-thickness front bulkhead gluing bottom half hatch cover now has no forward movement Prevent side ways movement fitting little feet hatch cover slip inside longerons Make small adjustments hatch fits snugly position secure nylon bolts small platforms glued bulk heads inside fuselage can take cap tive nuts Recessed bolts help appearances Making pilots gunners canopies first think about awhile Since chance finding anything ready-made approximates right size shape nil have no op tion make yourself method chose heat-mold oven using molding tool finding way position clear acetate sheet securely newly found expertise area welcome Choose piece balsa big enough task Using drawings perhaps photographs carve sand pretend can opy will sit place fuselage inside part sits nicely either before after cutting away unwanted part fuselage begin carve shape canopy itself Balsa easy work type job since lot so-called carving reality coarse sanding rather actual shaping carvers tool solid balsa canopy appears just right eye make hole underpart crea tion accept handle choice used 4-in length -in doweling sure epoxy handle well has work canopy-and-handle unit serves molding tool Give good hard var nish Next make wood bed little bigger plan size tool sup ported feet high enough tool can go through matching hole mat tress leaving bit space say around can move tool out nicely take piece thin acetate sheet pin way around close hole push pins work fine Now comes fun part things 58 Model Aviation seems shame hide structural work like underneath covering Scale model full-size bombers have never known fOr having see-through wings Left Inside structure details cockpit hatch Right one-piece removable cockpit hatch give total access inner workings quiet kitchen mama out shop ping turn electric oven maxi mum heat oven has preheated high will go put bed metal tray oven leaving main door open inner glass door shut Watch what happens closely After about minute will see acetate beginning ripple meaning has softened heat Before collapses take out bed its tray grab tool pronto push firmly hole bed acetate has softened correctly tool will force accept its shape have lucky tool will now below mat tress level will soon cool its cool enough handle gently wiggle tool back forth until sepa rates acetate now has just shape intended Remove bed trim off frilly part skirt its set fitted fuselage Dont expect good results first time tempt heat-mold procedure its bit knack get right may need try before youre successful pilots canopy after final trimming nice fit can edge glued place Use short lengths masking tape hold position during setting gunners can opy prototype quite cleverly hinged its opened back half becomes windshield front part disappears inside fuselage Wellesley gunners kept canopy open al time being very little air turbulence generally warm air over Af rica Making models canopy swivel though would have complicated also impractical standpoint canopy will stiff using thin ac etate sheet permanently closed want realism swivel can opy no harm trying make gunners canopy permanently closed dont forget make up lifelike Lewis gun mount cut slot fixed metal com partment prototype rear canopy stowage gun task cutting away part fuse lage underside accommodate wing spars may done now left until after main part wing has con structed modelers discretion latter sequence may better either way method same After marking unwanted areasthe main spar thin rear sparcut out fretsaw knife building up ends big cutaway ply shape upper line cutout must coincide root wing ribs idea being fu selage fits onto wing other way around low-slung wing Vickers Wellesley Mk 1 Single-engined RAF tight bomber Model scale 1/10th based L2714 wartime identity letters AO-A No 223 Squadron RAE Dimensions Wingspan895 Wing area6298 sq ft 907 sq Wing sectionRAE32 Root chord15in Tip chord65in mci balsa tip Aspect ratio88 Fuselage length47in Wing dihedral21/20 Wing washoutouters30 Engine Enya 40-4C four-stroke 65cc 1/2 hp PropellerTornado reinforced nylon 121/2 x 5 Maximum rpm ground run 8500 Weights Fuselage tail unit motor fuel tank 43 oz Wing complete Rom-Air gear z Radio8 servos 6 channels 18 oz Bomb containers 4 oz FuelS fluid oz 4 oz Total 127 oz 7 lb 15 oz Nominal 2 oz ballast added damp down elevator response necessary Wing loading 8 lb wt 0 ozIsq ft Control throwsat trailing edge Elevator way Rudder 1 way Ailerons % up % down Flaps 11/2 full down approx 400 makes sense have supporting fuse lage times Dont dismayed small amount fuselage material re mains after the big cutout accommo dating wing has made hatch removed isnt cause con cern Suitably strengthened balsa planks favorite /64 ply side its frame fuselage tougher appearsready perils flying life crashes Once three jobs done rest fuselage construction basically con ventional spiced few specific adapta tions Two beechwood engine bearers 5 long in cross section slotted bulkheads also pro vide platform special fuel tank slightly offset make room engine servoa snug fit space available Its remarkable much design work has done certain areas ac commodate essential items Once engine bearers have fitted supplementary platforms radio gear ser vos etc can provided suit individual preference however recommend locate everything along lines Wellesley way youll least know everything works together logical fashion have good access parts space behind Enya 40-4C engine front bulkhead filled aluminum sheet cowl top half shaped paper pattern made ear lier screwed thick front bulkhead bottom half thin ply glued place pilots cockpit also part fuse lage construction After cutting out small cockpit area hatch cover make wooden replica windshield framework will probably have noticed order simulate solid front sec tion fuselage going back far cockpit balsa sticks have sandwiched between longerons stringers solid structure nicely sanded down sists making neat job cockpit sur round windshield frame made match drawing applies equally canopy minor trimming can June 1988 59 opy will needed before final test fit gluing Make certain however thing position before glue since af terwards youll have no further access cockpit except inside hatch removed simulated glass windshield panels made clear Plexiglass cut thick enough look good little care shaping panel before gluing will give realistic ap pearance Dont forget human eye tends look things some kind prior ity case Scale model its cockpit area attracts Wing Wellesley somewhat other airplane Im familiar constructing wing key crucial step model priority consideration get near geo detic construction prototype possi ble Almost important decision use well-proven system removable outer wings Boston radio setup dictated fact fuselage would sit wing just four bolts keep decided mount aileron flap servos together Rom-Air unit wing accommodating other components within fuselage makes preflight assemblyand post-flight disassemblyas simple foolproof possible As prototype starting point wing construction Y-shaped main spar design gives great strength its needed also accommodates landing gear nicely spar fashioned primarily top bottom sticks 14 x /16 spruce supplemented vertical grain balsa webs beefed up ply facing near wing roots before assembly spars very sturdy initial stages construction wing structure consists four master ply ribs distributed along inner wing assem bly shown drawings cut trimmed glued position Cut small narrow vertical slots outboard master ribs accommodating wing joiners refer plans Port star board wings constructed separately spruce spars projecting two inches beyond wing root ribs form struc ture center section Place wing skeleton wing plan drawing add balsa shaped leading edge spar rear spar latter built up -in strip balsa medium hard / ply facings Glue face separately ply being little oversize sand down afterwards will get light stiff spar trouble three spars glued integrally four master ribs before begin ning geodetic construction phase install balsa platforms flap aileron servos according drawing loca tion seems work out fine given de sign factors involved access panels very thin ply can secured very small self-tap screws suitably posi tioned small hardwood blocks no need quick access field Youre now ready turn two halfwing skeletons geodetic ones Using geodetic lines drawing roughly correspond prototype pre pare large quantity balsa sticks /16 soft sheet balsa about % wide Work ing along panel upper part frame cut fit sticks edge up herringbone pattern Run same pattern opposite direction cutting fitting sticks slot original ones creates arrangement diamond shapes squares somewhat resembling egg-crate An important point remember sticks positioned little higher wing contour Next make sanding stick Cover straight batten about 1 x 114 just little longer span half-wing sandpapercoarse side fine other halfwing lap begin sanding evenly across span structure working grain balsa sticks wherever possible Soon wing contours begin show have sanded down almost point touching master ribs use fine sandpaper finish off now have nicely shaped accurate tapered wing geodetic construction wing has strength spare could fact build acceptably strong using less material wing gener ously built still light needs hold back RAF 32 airfoil dupli cates the prototype par ticular airfoil must can substi tute nice-looking NACA biconvex version thats minimum two inches deep root chord Once first wing half looking good topside turn over create same airy basket weave contours underside Repeat process both sides other wing half routine beginning stale least know end product justifies means Wellesleys geodetic wing singularly twist-free light Now youre ready join wing pan els together first step make jigs support wings positioned drawings jigs must provide secure base give necessary 2 0 dihe dral prototype Equally important wing half must have precisely identical rigging angles fore aft pays work carefully accurately process wings carefully positioned over drawing ballasted necessary keep steady jigs angles correct whole business symmetri cal connect spruce spars project fuselage bay spruce cut shape like epoxy job its quick drying strong main spar connected repeat rear spar shaped front balsa spars have joined since main spar its doubled Y configuration provides strength enough Remove inner wing jigs beef up spar assembly vertical grain balsa join has taken place Check eye looks good Add three-ply faces spar make extremely serviceable cen ter section job have specific use well provide location brack ets accept nylon bolts attach fuselage wing Trial fit fuselage main part wing making usual adjustments alterations get right wing root ribs should bed nicely cutaway part fuselage wing must dead square fuselage centerline Continued page 138 60 Model Aviation Left The left wings outer panel Du-Sro quarter-turn latches secure inspection hatch twin belicrank elevator con nected servo cables Note lower edge rudder prolects forward way aft end tail wheel mount RC Helicopters/Jolly Continued page 135 possible go flybarless rotor head Ive flying GMPs heads flybarless several years now have excellent re suits modifying following way center yoke bandsawed off top machined portion head head assembled normally except damp ening must tight possible Rang ers ran GMP blades cut rotor diameter 58 blade ballasted center-of-gravity-corrected weight 190 grams Set up way ships superb fly Because use no mixer headjust two links direct swashplateI must cut down collective cyclic throws can quite excessive try heads flybarless just make sure dampening tight throws reduced head gets normal pitch changes youll really like flying flybarless Also 190-gram blades autorotations dream fact night flying Rangers just set down ground Being cute hit throttle hold pulled up collective head has much inertia Helicopter lifted higher head settled slowly back ground thought sure would run out blade speed bend bird up honest soft touchdown achieved So finished three Rangers time shipped ahead Globe AZ film ing would take place arrived two days later uncrated beauties finding minimal damage flicted air freight kind winced found Out would flying elevation 4000 ft Believe nothing gets director excited watch ing flying bomb winding up wanting lift off loaded 13 lb Cobra/ Rangers flew excellentlyeven altitude Franidy after building three Helicopters shipping location span month flying anticlimactic director picked out rock face locked off two high-speed cam eras panned two hit spot first time Id used real explosives like potassium nitrate primer cord weird have machine strike wall see flash observe total disintegration fuselage mechanics falling ground As loaded up after destroying third ship thinking grateful could de pend various model companies provide quality equipment capable doing job safely Anyway see Midnight Run look small part model aviation played give believable explosion New GMP machine coming Gorham Model Products has just given permission nounce new aerobatic Helicopter Leg end have flown prototype can tell Legend quite capable dar ing acrobatic maneuvers GMP will showing ship Toledo made show saw public display first time Anyway Legend still cooperative ef fort between Gorham Hirobo lot Gorham Legend features flybar less rotor head toothed-belt tail rotor drive ex tremely light weight John says de mostly two new space age materials called aluminum steel As soon can get some pictures Ill give preview BCNU Wellesley/Pelly-Fry Continued page 60 thin three-ply flaps split type hinged rear spar three points side flaps lightly braced fore aft along inside span make rigid Small cutaways under wing accommodate will give snug fit flap bellcrank fitted coincide servo location Using servo flap merely conveni ent rather technical necessity Its easy harmonize two servos adjust ments devises method constructing wing out ers same main inner wing ailerons having recessed hinge Set up port starboard wings spe cially made jigs making provision three degrees washout cut sand soft balsa wing tips shape glue place Finish covering outers nylon Before constructing ailerons provide access aileron bellcranks using Du Bro quarter-turn latches As shown drawing aileron consists basically number balsa ribs half-round lead ing edges aluminum tube spar located fat point rib section trailing FOAM WING CORES muuumuu.uuuuuumummu.uuuuuuuuuuu.uuummm U U I PRECISION MADE EXPANDED BEAD POLYSTYRENE REPLACEMENT WING & STAB CORES FOR ALLI POPULAR RIC AIRCRAFT OVER 250 DIFFERENT WINGS IMMEDIATE DELI VERE SO IF YOU HAVE U AFAVORITEBIRD THAT NEEDS WING CALL OR WRITE USI I- SEND $350 FOR OESCRIPTIVB PRODUCT CATALOGj I U U U U II U U U U U uuuemmuuumumuUUuuuuuummmuuum..~... /VG MFG WING MPG P0 BOX 33 CRYSTAL LAKE IL 60014 p p pg S 0 AMERICAN JR OM RIDGE CAMPBELL T RITE DUBRO EASY BUILT MODELS FLYLINE FOX BERG DUBOIS LOW K&B MICRO X OS MAX RA PECK-POLYMER ECT MODELS SEAGLEN STERUNG IVAN SUPER TIGER INDER PLITE LER WILLIAMSS PRODUCTS RS ESTES MODEL ROCKETS Send Si Caeh Cheek ow Stamp eur 32 page tabloid size DISCOUNT Catalog 900 jItosttions ove 700 Kits choose Io, MAILOROER PHONEORDER IN STORE PENN VALLEY HORNY CENTER 837 1 Main St LansdalmVa 19445 138 Model Aviation REPRODUCTION PARTS FOR ANTIQUE IGNITION ENGINES o SPARK PLUGSa TANK TOPSa POINTS o TIMERSo GASKETSoTANKS o NEEDLE VALVESa SCREW SETSo COILS o EXHAUST STACKSe MANUALSa PROP DRIVES OVER 1000 ITEMS FOR MORE THAN 60 ENGINES SEND $4 FOR CATALOG #10 IN US & CANADA INTERNATIONAL $7 air mail MICRO MODEL ENGINEERING 1301 W LAFAYETTE ST STURGIS MI 49091 LL Fu sToo ng P0 Box 95 Champaign lLDiou
Edition: Model Aviation - 1988/06
Page Numbers: 52, 53, 54, 55, 56, 57, 58, 59, 60, 138
EGroup Captain James Pelly-Fry Unique construction hallmark RAF bomber Brit ish used Ethiopia against Mussolini during early years WW II RC model design bit history come us men actually flew full-size plane action PART OF THE ROMANCE Scale aero modeling lies rescuing obscure forgot ten long-lost aircraft oblivion giving second life Searching details data necessary recreate old aircraft satisfying itself also adds another dimensionthe thrill huntto rewards pleasures acquiring expertise model builder Vickers Wellesley example just such long-forgotten discarded air craft long-range single-engine RAF bomber piloted World War II uncommonly efficient construction interesting history well worth know ing about brainchild Sir Barnes Wal lis Later war designed airships bouncing bomb destroyed huge dams Germany Wellesley flown successfully day night over Ethiopia against Mussolinis forces remarkable aircraft possessed ex ceptional load-carrying capabilityeven standard form could lift much its own weight 1938 three specially equipped Wellesleys flown nonstop over 48 hours Egypt Australiaa just-over-7 000-mile trip overturned world record distance held until Russia Fifty years ago 7000 unbroken miles fairly impressive achievement privileged command Wellesley squadrons having served second-in-command another squadron earlier war found air craft well exceeded expectations also piloted Douglas A20 Bob Wis cher has successfully built test flown Flying Scale model Wellesley comes second scaled-down version 52 Model Aviation Top extra wingspan lightweight construction enabled long-range RAF bomber lift much its own weight Above Its great thrill resurrect old de sign its particularly exciting bring plane back since no full-size version remains one-time military prototype person ally flew aviator As full-size aircraft both Douglas Wellesley did su perlative job very different wartime cir cumstances both have equal place sentiments salient characteristics Welles ley its very large wingspan 74 ft prototype good news model version use unique form air frame construction Barnes Wallis called geodetic consisting essentially double-spiral structure fuselage what might called basket weave wing stabilizer geodetic construc tion gave Wellesley exceptional light ness strength cardinal rule airplane design wing particular both extremely light very strong So far know single Wellesley specimen has recovered posterity left desert fate after Allied Forces moved Southern Europe Thus designing scaled-down version worthy aircraft researchthe aforementioned huntwould have lim ited whatever drawings sketches photographs could obtain Beaumont Avi ation London specializes keep ing records aviation data old maga zines books etc supplied some valuable material fortuitous coincidence also helped Matchbox Model Company recently produced 12-in-span stick together Wellesley kit ex Construction Once sufficient data work has collected piv otal step Scale design decide upon suitable scale choose hardware determined rest followsprob lems Wellesley after doing some figures back old enve lope chose Mo-scaleas RAF Boston counterpart A20 way Id get big wing keep wing loading down reasonable figuresthe perennial aim often eludes Scale modeler wingspan would 90 hoped get weight down around eight pounds power plant Enya 40-4C fourstroke seemed promising Id successfully fitted pair A20 RAF Bos ton case also happened have engines spare good friend Bud Voss uncertainty con cerned whether Enya sufficient power get big Wellesley airborne June 1988 53 cellent material supplied cooperative manufacturer got started proj ect Top particular model version plane once flew 223rd RAF Squadron Wellesley set distance world record 7000 continuous miles 1938 Above author rendition bombers piloted actually serving squadron commander during World War II scaled down one-tenth actual size big model flying safely Enya proved equal task landing gear supposed tail-down retractable job decided stay proven productthe excellent Rom-Air type As Boston gives creditable service very high wing loading sometimes occasions dramatic arrivals touchdown seemed natural choice use known entity Fuselage Fairly conventional construction used geodetic inner framework omitted sake weight-watch ing leaving four longerons stringers prototype establish correct oval shape cross section practice fabric covering used aft pilots cockpit course number flats sufficient number stringers employed maintain gen eral oval shape critical eye fuselage made up two halves using datum line straight along center line between top bottom halves method gives good foundation construction Mosquito employed es sentially same procedure dif ference being Mossie fuselage joined up top-and-bottom rather like chocolate Easter egg A-in-thick three-ply bulkheads TO I MAKE 2 MAKE RU 3RINS MA TRIM MAPLE MOTOR M U SHAPE BRA1 SCALE VOKES CARB FROM BALSA RLOCKS EV RUDDER SEEN PROM REAR H VB I/5 BALSA POST3 3/16 BALSA PIN 7 RUDDER F AME / I/I6 BALSA RI RINSEN LOCATION S TRIMTAB--H MUSC WRE TAILWHEE7 BRACEjXB BALSANOTSH BLOCKASEE TE XDETA LS S DA TALWHEEL 0IS345 constructed drawings appro priately slotted take north-south east-west longerons intermediate stringers completed cut across horizontal centerline using razor saw removes minimum timber useful number bulkhead go situated behind pi lots canopy has duplicated provide endpiece removal hatch reason make sure lower halves twin bulkhead glued gether top halves just lightly spot glued subsequent separa tion double lower bulkhead gives added strength rear spar wing passes through fuselage later Lay out full-size drawing top view fuselage building board steam shape first pair 4 x A-in spruce obechi sticks lie flat joined together 54 Model Aviation Using run-up table makes easier get everything assembled perform engine adjustments See text details making polystyrene external bomb containers Operating flaps slow big model down floating touchdowns add realism real beauty model lies just below its skin unique geodetic construction used designer Barnes Wallis give Wellesley lots strength lots weight Full-Size Plans Available. See Page 164 F WOOS .ASS B EPOXY ENGINE ORBOMB BOX IS MADE FROM FOAM BLOCK AND COVERED WITH FIBERGLASS EPOXYBOOS SUPPORT FRONT VIEW SCRAP WOOD SUPPORTS SAND TO AIRFOIL SHAPE SIDE VIEW USELAGE TOP VIEW NOTE FORMERS B THRO H ARE I/B PLYWOODTRIM AND NOTCH PER B F FIN CROSS IONREAR CLEAR PLASTIC CANOPY ENS SERB lIlY RUCTION FUSELAGE SIDE VIEW BOMB BOX y C I/4 PLY 1/B PLY -FORMERS-___ ---____________________ --I/G SO BALSA STRINGERS SPAR LINE I/4 I/lB BALSA LONG ERONS FIBERGLASS TOWNEND RING -x I/RPLYWOOO1/4 PLYWOOD / II LS MAPLE MOTOR MOUNTS K I FORWARD CLEAR PLASTIC CANOPY CLEARFUEL TANK PLASTICREMOVABLEVENTS WINDOWHATCH LINE C/771 E5OZFUELTANK SI/lB PLY FLAPS FLAP HORN ELEVATOR SERVO-i 2-I/ST INCIDENCE CS Y\ELAEJ--LSRyg I/32 PLY WHEEL COVERS WHEELS RCVR 5rNI II - ERY lID 3/B MAPLE MOTOR MOUNTS CLEAR PLASTIC WINDOW FIBERGLASS TOWNEND /1 oif i$ 40- 4 CYCLE ENGINE --c- I-S/B DIA SPINNER SHEET OF 2 MODEL AVIATION VICKERS WELLESLEY DESIGNED BY GRP CAPT JAMES PELLY FRY TRACING BY JOE DEMARCO RESERVED counterparts form completed longe rons Having pinned two sticks down securelyI pin either side through themtake top half-bulkhead hoop sequence glue its correct location Its best time hoop pretty unstable its small base halfbulkhead hoops glued position quick results used epoxy sup ported hoop anything handyso long hoop remained dead upright dur ing glue setting front bulkhead dou ble thickness ply strength Steam bend shape top longe rons again 1/4 x % Slot glue half-bulkhead hoops Slot glue %-in-sq balsa string ers fitting alternately avoid distor tion top half fuselage semicomplete sturdy enough handle re move building board An Enya 40 four-stroke provided plenty power model Note wire remote glow plug connector fuselage beams may look flimsy theyre plenty strong enough June 1988 55 drawing Place somewhere level weights bottom longerons pre serve true shape begin over again construction lower half fuselage constructing fuselage half keep mind its unnecessary stringers go way back theres much room anyway thin back end So its good idea shorten other suit eye case remove stringers last bay tail unit located Another im portant reminder Take great care second half fuselage duplicates first exactly possible particu larly true midpoint longerons must either glued fitted together inspection access hatch location Its impor tant take pains craftsmanship early stage project After checking two identical fu selage halves join together exactly apply glue along edgeswith important exception front half longe rons will glued just fitted gether what call touching fit around inspection hatch area youll separating hatch razor blade later Bring faces both glued fitted together secure along entire length springloaded office-type bulldog clipsvery handy grip firmly can fitted hand now have nicely shaped fairly stiff fuselage frame oval bulkheads have rigidity will ever needthe nylon covering add later will support moreand fuse lage length joined-up parts become good strong 14 x A-in-sq section forming master longerons along centerline Before setting aside masterpiece Im sure family friends will agree remove stringers last end bay tail unit will located will later replaced super-thin three-ply screwed place form ac cess hatches main hatch up front quick-remove can temporarily left spot glued place allow get used its new shape Empennage greatest need back end maximum lightness combined adequate strength flight ground handling fraction superfluous weight tail model roughly equivalent putting four times much nose Building light tail order exact weight penalty cannot stressed too strongly too often par ticularly Scale modeling basic layout prescribed external shape prototype builder finds after installing essential items like en gine fuel tank servo radio battery etc well up front still needs add much-dreaded ballast correct balance point Some Scale models need much two pounds lead squeezed nose offset tail weight thats terrible handicap Models short noses present biggest problems thus tend avoided Because requirement lightness materials stabilizer elevators fin rudder chosen great care kept judicious minimum wood primarily soft balsa plus small amount hard balsa little / super birchwood ply made Finlandthe latter strengthen both sides stabilizer main spar rudder post thin ply glued side separately keeping little oversize sanding down shape spars taper slighfly out tips theyre made up check twist during construction theyre weighted down during gluing allowed dry out well will remain straight true 2-in aluminum tube used connect elevators attach homemade control horns As fuselage make empen nage over drawings ensure accurate shape subtle curves give model its realism stabilizer distin guished its lattice-work geodetics elevators slightly off-center i/B PLY R-5~21/8 PLY EL I/B 1/5 BALSA 8-7 SMALL HINGES TO SUIT F SOFT BALSA BLOCK WING liPS HI LI STABILIZ GE IC LINES I/E S/lB BALSA-KEEP IT LIGHT-GEE TEST DETAILS BUILD FRAME FROM LAMINATES BALSA CROSSSECTION ALSALES R Left The air tank Rom-Air retracts servo operates valve inspection covers held place six self-tapping screws blisters necessary accommodate wheels Right Small inner covers wheel wells closed wheel itself upon retraction gear down weighted arms small doors keep open Plastic straps cover hole gear up 56 Model Aviation Full-Size Plans Available. See Page 164 R-6I/B PLYY SPAR IS /41/16 SPRUCE I/B PLYBOMB BOX LOCATIONWITH BALSA VERY SRAIN WEBS HORN MOUNTSEE TEST LEFT WINGWINS JOINT -LINE PLYAILERONR-I HORNB-S N-SILERO N-B-SERV -R -N C --ROM-AI RETRAC/ CB-BASEPLA/ IN / APBEPUBOS P0AERV L SR ROD AILERONS ARE BUILT UP SPARREARWITH BMSA RIBS SEE TEXT PLYSPAR DIHEDRAL 5-1/5 2FLAPS ARE I/IN PLY UNDER WINS5/16 PLY PLY RIBSEOOETIC LINES I/IN SEEP BY S/B WIDE BALSA SECTION ROOT CHORDSEE TEXT FOR CONSTRUCTIONR-2% SIB BALSA LE TAPEREDI/B PLY -RIGHT WING B-S AlONB-SR R ERV -A- SERVO FLAP AILERON HORN VICKERS WELLESLEY PLY HORN I161JNT DESIGNED BY GRP CAPT JAMES PELLY FRY BALSA YE STOCK0IS54BBTRACING BY JOE DEMARCO IIIII IGHTS ft SHEET 2 OF 2 MODEL AVIATION horns avoid contact rudder fin-rudder assembly completed have full travel latter influenced conventional Use small plastic necessarily covered stage now shape inboard part eleva hinges slipped pre-cut slots cor- set up fuselage Make provision tors sweep stabilizer rect midline points frame glued foot spar rudder post spar practice Wellesley does minimum epoxy Check secur- spar standing glued onto small need much application rudder normal ity pulling gently hinge after block rudder course has move flight since ailerons epoxy has cured may next freely double arms horns must work model ailerons coupled day trick fitting stabilizer eleva tors fuselage cut away lead ing edge spar sufficiently enable maneuvered place Once thats done stand fuselage its nose floor steady glue main spar onto back rearmost bulkhead midpoint Theres very little room area work carefully accurately mak ing sure stabilizer dead square fuselage upright Once epoxy has set can build up broken lead ing edge short piece hard balsa glued bulkhead along side using filler piece necessary June 1988 57 Detail geodetic wing construction locations aileron flap servos Left Band-sawing soup can half soldering tin across flat bottom resulted nice looking custom fuel tank Right molding tools beds used make canopies see text details right aerodynamically clean Townend cowl rudder least time being may change separate controls later Once again rehearse final assembly glu ing making sure everything true accurate beforehand Replace stringers cut away earlier last end bay fuselage four shaped pieces / ply will provide access moving parts tail elevator rudder steerable tail wheel builder prefers stringers can left out first place since chance fuselage twist slight four small very light panels secured bulk heads very small self-tap screws spare weight put just enough no little visual embellish ment adds almost nothing weight quarter-section ping pong ball can fitted glued edge top half rear bulkhead elevator rudder controls closed-loop type Closed-loop systems work fine save weight used very lightweight fishing trace wire nylon cov ered should no 10-lb break ing strength assembling servo coupling up wires use miniature fishing tackle swivels servo end fish ing gear ferrules trap wire coupling up nip two wire cutters advantage swivels can ad just correct tension removing clevis worse twisting wire Allow enough slack wires can move sideways about midpoint end-to-end approximately ly tight wires bad servos steerable tail wheel 2 A-in dia light can find mounted made-up fork piano wireabout 16-gauge just stiff enough job Bind ends thin wire solder lightly slide piece aluminum tube glue epoxy Trim wire ends unit fits another tubeyou want nice sliding fitwhich epoxied built-up unit fuselage use balsa pieces give rigidity Test smooth movement Make up own crank horn carefully epoxy collar type used landing wheels Locked grub screw collar traps inner tube top projects above bear ing its horn connects arm rudder horn now have good steer able tail wheel adjustable cor rect tracking taking off taxiing also removable neces sary book neat taxiing straight down-the-dotted-line takeoffs add re alism model flight point backtrack front end fuselage few major jobs have done before proceeding other work make access cover removable b cut away part fu selage form air-gunner/radio mans position make pilots gunners canopies c cut away part fuse lage underside accommodate wing root double spars make hatch access cover remov able begin slipping razor blade tween centerline longerons break spot gluing will free cover nicely help retain its shape after removing cover fit small strut across back hatch fit front would prevent putting taking off cover cover off glue place double-thickness front bulkhead gluing bottom half hatch cover now has no forward movement Prevent side ways movement fitting little feet hatch cover slip inside longerons Make small adjustments hatch fits snugly position secure nylon bolts small platforms glued bulk heads inside fuselage can take cap tive nuts Recessed bolts help appearances Making pilots gunners canopies first think about awhile Since chance finding anything ready-made approximates right size shape nil have no op tion make yourself method chose heat-mold oven using molding tool finding way position clear acetate sheet securely newly found expertise area welcome Choose piece balsa big enough task Using drawings perhaps photographs carve sand pretend can opy will sit place fuselage inside part sits nicely either before after cutting away unwanted part fuselage begin carve shape canopy itself Balsa easy work type job since lot so-called carving reality coarse sanding rather actual shaping carvers tool solid balsa canopy appears just right eye make hole underpart crea tion accept handle choice used 4-in length -in doweling sure epoxy handle well has work canopy-and-handle unit serves molding tool Give good hard var nish Next make wood bed little bigger plan size tool sup ported feet high enough tool can go through matching hole mat tress leaving bit space say around can move tool out nicely take piece thin acetate sheet pin way around close hole push pins work fine Now comes fun part things 58 Model Aviation seems shame hide structural work like underneath covering Scale model full-size bombers have never known fOr having see-through wings Left Inside structure details cockpit hatch Right one-piece removable cockpit hatch give total access inner workings quiet kitchen mama out shop ping turn electric oven maxi mum heat oven has preheated high will go put bed metal tray oven leaving main door open inner glass door shut Watch what happens closely After about minute will see acetate beginning ripple meaning has softened heat Before collapses take out bed its tray grab tool pronto push firmly hole bed acetate has softened correctly tool will force accept its shape have lucky tool will now below mat tress level will soon cool its cool enough handle gently wiggle tool back forth until sepa rates acetate now has just shape intended Remove bed trim off frilly part skirt its set fitted fuselage Dont expect good results first time tempt heat-mold procedure its bit knack get right may need try before youre successful pilots canopy after final trimming nice fit can edge glued place Use short lengths masking tape hold position during setting gunners can opy prototype quite cleverly hinged its opened back half becomes windshield front part disappears inside fuselage Wellesley gunners kept canopy open al time being very little air turbulence generally warm air over Af rica Making models canopy swivel though would have complicated also impractical standpoint canopy will stiff using thin ac etate sheet permanently closed want realism swivel can opy no harm trying make gunners canopy permanently closed dont forget make up lifelike Lewis gun mount cut slot fixed metal com partment prototype rear canopy stowage gun task cutting away part fuse lage underside accommodate wing spars may done now left until after main part wing has con structed modelers discretion latter sequence may better either way method same After marking unwanted areasthe main spar thin rear sparcut out fretsaw knife building up ends big cutaway ply shape upper line cutout must coincide root wing ribs idea being fu selage fits onto wing other way around low-slung wing Vickers Wellesley Mk 1 Single-engined RAF tight bomber Model scale 1/10th based L2714 wartime identity letters AO-A No 223 Squadron RAE Dimensions Wingspan895 Wing area6298 sq ft 907 sq Wing sectionRAE32 Root chord15in Tip chord65in mci balsa tip Aspect ratio88 Fuselage length47in Wing dihedral21/20 Wing washoutouters30 Engine Enya 40-4C four-stroke 65cc 1/2 hp PropellerTornado reinforced nylon 121/2 x 5 Maximum rpm ground run 8500 Weights Fuselage tail unit motor fuel tank 43 oz Wing complete Rom-Air gear z Radio8 servos 6 channels 18 oz Bomb containers 4 oz FuelS fluid oz 4 oz Total 127 oz 7 lb 15 oz Nominal 2 oz ballast added damp down elevator response necessary Wing loading 8 lb wt 0 ozIsq ft Control throwsat trailing edge Elevator way Rudder 1 way Ailerons % up % down Flaps 11/2 full down approx 400 makes sense have supporting fuse lage times Dont dismayed small amount fuselage material re mains after the big cutout accommo dating wing has made hatch removed isnt cause con cern Suitably strengthened balsa planks favorite /64 ply side its frame fuselage tougher appearsready perils flying life crashes Once three jobs done rest fuselage construction basically con ventional spiced few specific adapta tions Two beechwood engine bearers 5 long in cross section slotted bulkheads also pro vide platform special fuel tank slightly offset make room engine servoa snug fit space available Its remarkable much design work has done certain areas ac commodate essential items Once engine bearers have fitted supplementary platforms radio gear ser vos etc can provided suit individual preference however recommend locate everything along lines Wellesley way youll least know everything works together logical fashion have good access parts space behind Enya 40-4C engine front bulkhead filled aluminum sheet cowl top half shaped paper pattern made ear lier screwed thick front bulkhead bottom half thin ply glued place pilots cockpit also part fuse lage construction After cutting out small cockpit area hatch cover make wooden replica windshield framework will probably have noticed order simulate solid front sec tion fuselage going back far cockpit balsa sticks have sandwiched between longerons stringers solid structure nicely sanded down sists making neat job cockpit sur round windshield frame made match drawing applies equally canopy minor trimming can June 1988 59 opy will needed before final test fit gluing Make certain however thing position before glue since af terwards youll have no further access cockpit except inside hatch removed simulated glass windshield panels made clear Plexiglass cut thick enough look good little care shaping panel before gluing will give realistic ap pearance Dont forget human eye tends look things some kind prior ity case Scale model its cockpit area attracts Wing Wellesley somewhat other airplane Im familiar constructing wing key crucial step model priority consideration get near geo detic construction prototype possi ble Almost important decision use well-proven system removable outer wings Boston radio setup dictated fact fuselage would sit wing just four bolts keep decided mount aileron flap servos together Rom-Air unit wing accommodating other components within fuselage makes preflight assemblyand post-flight disassemblyas simple foolproof possible As prototype starting point wing construction Y-shaped main spar design gives great strength its needed also accommodates landing gear nicely spar fashioned primarily top bottom sticks 14 x /16 spruce supplemented vertical grain balsa webs beefed up ply facing near wing roots before assembly spars very sturdy initial stages construction wing structure consists four master ply ribs distributed along inner wing assem bly shown drawings cut trimmed glued position Cut small narrow vertical slots outboard master ribs accommodating wing joiners refer plans Port star board wings constructed separately spruce spars projecting two inches beyond wing root ribs form struc ture center section Place wing skeleton wing plan drawing add balsa shaped leading edge spar rear spar latter built up -in strip balsa medium hard / ply facings Glue face separately ply being little oversize sand down afterwards will get light stiff spar trouble three spars glued integrally four master ribs before begin ning geodetic construction phase install balsa platforms flap aileron servos according drawing loca tion seems work out fine given de sign factors involved access panels very thin ply can secured very small self-tap screws suitably posi tioned small hardwood blocks no need quick access field Youre now ready turn two halfwing skeletons geodetic ones Using geodetic lines drawing roughly correspond prototype pre pare large quantity balsa sticks /16 soft sheet balsa about % wide Work ing along panel upper part frame cut fit sticks edge up herringbone pattern Run same pattern opposite direction cutting fitting sticks slot original ones creates arrangement diamond shapes squares somewhat resembling egg-crate An important point remember sticks positioned little higher wing contour Next make sanding stick Cover straight batten about 1 x 114 just little longer span half-wing sandpapercoarse side fine other halfwing lap begin sanding evenly across span structure working grain balsa sticks wherever possible Soon wing contours begin show have sanded down almost point touching master ribs use fine sandpaper finish off now have nicely shaped accurate tapered wing geodetic construction wing has strength spare could fact build acceptably strong using less material wing gener ously built still light needs hold back RAF 32 airfoil dupli cates the prototype par ticular airfoil must can substi tute nice-looking NACA biconvex version thats minimum two inches deep root chord Once first wing half looking good topside turn over create same airy basket weave contours underside Repeat process both sides other wing half routine beginning stale least know end product justifies means Wellesleys geodetic wing singularly twist-free light Now youre ready join wing pan els together first step make jigs support wings positioned drawings jigs must provide secure base give necessary 2 0 dihe dral prototype Equally important wing half must have precisely identical rigging angles fore aft pays work carefully accurately process wings carefully positioned over drawing ballasted necessary keep steady jigs angles correct whole business symmetri cal connect spruce spars project fuselage bay spruce cut shape like epoxy job its quick drying strong main spar connected repeat rear spar shaped front balsa spars have joined since main spar its doubled Y configuration provides strength enough Remove inner wing jigs beef up spar assembly vertical grain balsa join has taken place Check eye looks good Add three-ply faces spar make extremely serviceable cen ter section job have specific use well provide location brack ets accept nylon bolts attach fuselage wing Trial fit fuselage main part wing making usual adjustments alterations get right wing root ribs should bed nicely cutaway part fuselage wing must dead square fuselage centerline Continued page 138 60 Model Aviation Left The left wings outer panel Du-Sro quarter-turn latches secure inspection hatch twin belicrank elevator con nected servo cables Note lower edge rudder prolects forward way aft end tail wheel mount RC Helicopters/Jolly Continued page 135 possible go flybarless rotor head Ive flying GMPs heads flybarless several years now have excellent re suits modifying following way center yoke bandsawed off top machined portion head head assembled normally except damp ening must tight possible Rang ers ran GMP blades cut rotor diameter 58 blade ballasted center-of-gravity-corrected weight 190 grams Set up way ships superb fly Because use no mixer headjust two links direct swashplateI must cut down collective cyclic throws can quite excessive try heads flybarless just make sure dampening tight throws reduced head gets normal pitch changes youll really like flying flybarless Also 190-gram blades autorotations dream fact night flying Rangers just set down ground Being cute hit throttle hold pulled up collective head has much inertia Helicopter lifted higher head settled slowly back ground thought sure would run out blade speed bend bird up honest soft touchdown achieved So finished three Rangers time shipped ahead Globe AZ film ing would take place arrived two days later uncrated beauties finding minimal damage flicted air freight kind winced found Out would flying elevation 4000 ft Believe nothing gets director excited watch ing flying bomb winding up wanting lift off loaded 13 lb Cobra/ Rangers flew excellentlyeven altitude Franidy after building three Helicopters shipping location span month flying anticlimactic director picked out rock face locked off two high-speed cam eras panned two hit spot first time Id used real explosives like potassium nitrate primer cord weird have machine strike wall see flash observe total disintegration fuselage mechanics falling ground As loaded up after destroying third ship thinking grateful could de pend various model companies provide quality equipment capable doing job safely Anyway see Midnight Run look small part model aviation played give believable explosion New GMP machine coming Gorham Model Products has just given permission nounce new aerobatic Helicopter Leg end have flown prototype can tell Legend quite capable dar ing acrobatic maneuvers GMP will showing ship Toledo made show saw public display first time Anyway Legend still cooperative ef fort between Gorham Hirobo lot Gorham Legend features flybar less rotor head toothed-belt tail rotor drive ex tremely light weight John says de mostly two new space age materials called aluminum steel As soon can get some pictures Ill give preview BCNU Wellesley/Pelly-Fry Continued page 60 thin three-ply flaps split type hinged rear spar three points side flaps lightly braced fore aft along inside span make rigid Small cutaways under wing accommodate will give snug fit flap bellcrank fitted coincide servo location Using servo flap merely conveni ent rather technical necessity Its easy harmonize two servos adjust ments devises method constructing wing out ers same main inner wing ailerons having recessed hinge Set up port starboard wings spe cially made jigs making provision three degrees washout cut sand soft balsa wing tips shape glue place Finish covering outers nylon Before constructing ailerons provide access aileron bellcranks using Du Bro quarter-turn latches As shown drawing aileron consists basically number balsa ribs half-round lead ing edges aluminum tube spar located fat point rib section trailing FOAM WING CORES muuumuu.uuuuuumummu.uuuuuuuuuuu.uuummm U U I PRECISION MADE EXPANDED BEAD POLYSTYRENE REPLACEMENT WING & STAB CORES FOR ALLI POPULAR RIC AIRCRAFT OVER 250 DIFFERENT WINGS IMMEDIATE DELI VERE SO IF YOU HAVE U AFAVORITEBIRD THAT NEEDS WING CALL OR WRITE USI I- SEND $350 FOR OESCRIPTIVB PRODUCT CATALOGj I U U U U II U U U U U uuuemmuuumumuUUuuuuuummmuuum..~... /VG MFG WING MPG P0 BOX 33 CRYSTAL LAKE IL 60014 p p pg S 0 AMERICAN JR OM RIDGE CAMPBELL T RITE DUBRO EASY BUILT MODELS FLYLINE FOX BERG DUBOIS LOW K&B MICRO X OS MAX RA PECK-POLYMER ECT MODELS SEAGLEN STERUNG IVAN SUPER TIGER INDER PLITE LER WILLIAMSS PRODUCTS RS ESTES MODEL ROCKETS Send Si Caeh Cheek ow Stamp eur 32 page tabloid size DISCOUNT Catalog 900 jItosttions ove 700 Kits choose Io, MAILOROER PHONEORDER IN STORE PENN VALLEY HORNY CENTER 837 1 Main St LansdalmVa 19445 138 Model Aviation REPRODUCTION PARTS FOR ANTIQUE IGNITION ENGINES o SPARK PLUGSa TANK TOPSa POINTS o TIMERSo GASKETSoTANKS o NEEDLE VALVESa SCREW SETSo COILS o EXHAUST STACKSe MANUALSa PROP DRIVES OVER 1000 ITEMS FOR MORE THAN 60 ENGINES SEND $4 FOR CATALOG #10 IN US & CANADA INTERNATIONAL $7 air mail MICRO MODEL ENGINEERING 1301 W LAFAYETTE ST STURGIS MI 49091 LL Fu sToo ng P0 Box 95 Champaign lLDiou