Krackerjac Mk Mk II favorite oddcouple design team backthis time two-for-one like options build RC sport plane/ trainer combo Mark soars delightfully its higher performance sibling gets excellent marks hot-dogging U Bill Winter Bill Evans VOICE OFFSTAGE go again opposite schools design coau thors have managed second last presumes unlikely collaboration West Coaster Evans loves straight-up 140 0-plus flybys known philoso phy horizontal tails tantamount buggy-whip technology East Coaster pre historic old-timer Bill Winter go-slow airplane watcher thinks straight-up folks harbor hidden rocketry complexes Still found middle ground pro duced Krackerjac MK II Asked Evans would stoop build ing conservative cabin job conspic uous stabilizer Winter would say Whats nice guy like Bill Evans doing place like two collaborated Simitar Slow Motion published January 1987 issue Model Aviation docile flying wing almost easy fly Eaglet time Winters responsiveness Simitar proj ect flabbergasted Evans Winter ever did impose certain conditions First model soarso speed range set 15 80 mph plane fully controllable either rudder aileronsso equipped elevons Because specifications fuselage behind bobtail trailing edge termination extended some eight inches rudder post Since Winter also demanded extended pe riods hands-off flying modest dihedral added Indeed Slow Motion would 720s hands-off initial tap aileron stick save weight ship Krackerjac Mark pictured before its first flight flown Bill Winter couple years before being modified installing spoilers 6-ft-span 40-powered ship has wings stabilizer open-frame construction airfoil thin flat bottomed up main spar has long Phillips entry model has over 6 sq ft area under 19-ozIsq-ft loading will soar easily weak thermals airplane takes off climbs out 1A throttle will consecutive outside loops ttle fly about verted % throttle Bill added spoilers landings could easily made short flying fields Mk Bill Winters newest version Krackerjac seen doing what Bill likes besta slow flyby low altitude low throttle Model can equipped spoilers much like Thermal Soarers help control landings lightly loaded ship Tom Schmitt photo November 1990 83 little headwind model will tly ground cushion extremely low throttle Win ter claims times has able walk quickly beside model still airborne Mk floating its wheels just above grass Tom Schmitt photo tail-dragger protect old man Evans added foot span Aerobatic capability must K&B Veco 19 maximum power after adding second foot span bringing model six feet using 05 15 power performance essentially un changed did Evans Winter join gether second time Krackerjac Winter In 1960 good systems fullhouse control around about five years us could afford single-channel escapement airplanes Lacking elevator control designs addicted ballooning turns wind fly-aways commonplace original 54-in model called K rudder-only control quick-blip high/low throttle Max 15 ended non sense plane published Air Trails kitted Jetco Incidentally throttles time used exhaust stack re strictor coupled butterfly ven turi thin airfoil long Phillips en try secret models controlla bility original handled like multi llent penetration facility per fect touch-and-goes RCs over 40-year period three continue built Antique RC Special published 1948 early-60s Krackerjac reed-systems low-wing Rookie first published Model Airplane News early Sixties later some what modified publication Model Builder Other modelers have frequently im proved upon designs continue Several years ago obtained 6-ft ver sion Krackerjac 40 power plans service built model dozen test flights magazine ex pressed desire publish major manufacturer asked about kit mag wanted perfect pictures unfortu nately Id already marred covering stall spoilers wing efficient 6 sq ft 7A lb gross weight like Glider difficult get ground 300-ft strip Krackerjac soared ease dis covered day turning cross wind leg sixth flight noted no loss altitude did 360 ended up clouds Equipped 40 model demon strated considerable prowess took off climbed one-third throttle could fly inverted respond steering half throttle performed consecutive outside loops half throttle one-third down el evator Yet magazine staff thought plane should have 120 Hard believe told kit company opinion Krackerjac wasnt mainstream hence its best interests aircraft eventually given Doug Pratt converted K&B 40 to Enya four-stroke 46 Pratt has flown three seasons happened mention Bill Evans adding could get clean photos thought should published Evans Curiosity killed cat though find horizontal tails useless appendages Winters strange short-coupled cabin its big stab bottom odd appeal could build onemy way youll seeand fly within week Winter sent print Finding untried modification using semisymmetri cal airfoil 60 power phoned him ask Which would like build said might check out never-built aerobatic version Winter uses lots sticks Im always hurry So simplified fuse went foam balsa-skinned wing stab isnt neutrally stable prefer Winter wont give up measure hands-off control otherwise flies great Winter able join California watching pleased expressions flew per formance version treasured moments Ill never live down project has tail Everybody fly visits shop ribs unmercifully too much shipped model Winter year later Alas reports UPS stress tested wing found wanting Winter So now two airplanes different performance envelope working plan original good new pictures Evans Attempts revise original print tracer ran stone wall project sat 15 months Evans Dont ever get mixed up hair-splitting old-timers Theyll drive up wall kept asking Winter Whats problem Air Force project overruns delays would have provoked Congress hed draw wed done week Finally badgered him drawing incorporating sup plementary drawings decided show cross-options stuff crammed plans could come up least four differ ent ships Maybe should have sold National Geographic Surprise editor gave him green light two 40 x 52-in sheets proposed Winter designate original Mark call Mark II added Buddy East Coast now its own Winter Which build what ex pect Marks Design objectives MK easy piloting rather like 40-powered Senior Falcon Sig Kadet Goldberg Ea gle ability groove well maneuvers better average aerobatics enough reaction time prevent airplanes getting ahead average pi lot slow landings automatic takeoff though its tail-dragger ability ride weak general lift thermal soar Fly 84 Model Aviation close-up shot shows some details Mk built-up wing spoilers shown partially deployed control servos visible under transparent wing covering Steve Kaluf demonstrates short landing tech niques using spoilers plane will land observed attitude reserve flare can abort spoilers deployed Specs spoilers Size opening location etc shown plans tailored safe flight envelope ing techniques discussed end article low wing loading 19 ozI sq ft low drag result consistent ma chine sustains open maneuvers rela tively low power hands-off stability makes relaxed flying What about bigger engine Except improved vertical maneuvers brings added power self-defeating case 60 two-stroke limit youll find yourself doing aerobatics half power potent four-stroke such Enya 60 plenty Watch center-of-gravity such heavy engine An Enya 46 fourstroke does aerobatic maneuvers except advanced such knife-edge flight careful building can achieve gross weight seven pounds Mine turned out 7 lb spoilers two extra servos Some may come 8 lb because some always Dont load up paint Since ship can soar its lightly loaded large wing being equiv alent lower loading smaller wing has significantly higher Reynolds number long low approaches neces saryand critical small field obstacles beneath approach path may overshoot 300-ft strip model too high and/or too fast may wish consider spoiler option Spoilers allow make higher approaches land within first half strip Used front-hinge did create another fun mode flying described later MK Ls open-frame wing thin well large area heavy-handed pilot using oversized engine might overstress model example dive followed abrupt pullout overapplica tion up Evans MK H Winter specified airfoil incidence power 60 en gine version faster far Mark Its also spectacular groovy its closer being neutrally stable MK airplane still safe fly hands-off Winter said wanted two degrees dihedral own insur ance fuselage sides bottom shaped framed prepared ammbly ply gear plate place corner pieces will rounded later cross pIeces glued untrimmed bottom sheet grain running lengthwise side crosspieces trimmed exactly fit Note fishtail butt loint side sheeting above stabilizer saddle docile aircraft rather different fast neutrally stable machines Im used Still found nice fly wrung out Winter California handed controls over him Its measure planes easy handling low-speed abilities cruising about half throttle Winter held light back-pressure steadily ex ecuting towering perfectly round beauti ful loopall touching controls including throttle downside model seemed rails Throughout flight OS 60 gave him power wanted Very slight back trim slower stooging around resulted prolonged slight climb 2A-/3 airfoil ship will climb one-third throttle 60 foam wing balsa skin weighs ex actly same Winters open-frame MK wingfor total model weight 7 lb model robust enough kind flying wing thicker thing increased performance MK H can flown safely anyone aileron experience Like MK will fly ruddernice know since very slow approach rudder last control fail normal aircraft As shown used two exterior-mounted small Futaba servos ailerons Ive used arrangement de signs because its simple speeds up building Winter shocked first saw quickly agreed good way go now has same setup low-wing Desperado Simitar deriva tive anhedral wing reports no trace exhaust dirt servos Winter plans details op tions shown consider before making final decision MK presented basically com plete optional spoilers shown Though spoilers bring interesting dimen sion flying theyre required Cross sections outlines shown MK II wing tail Two versions wing shown Mine slightly modi fied two-bolt-and-dowel attachment Evans wing has four bolts panel can seen Evans external bottommounted servos linkage mod ified panel shows optional standard sin gle-servo arrangement Two profiles show mounting saddle semisymmetri cal wing near side view shows Evans reshaped cabin top four-bolt attachment other shows wing modified dowel two bolts Also shown Evans simpler open nose can substituted com plicated semi-enclosed nose MK Construction Fuselage Two techniques used ease assembly First bottom lies flat workbench Evans used length A-in soft sheeting grain running length wise bottom glued A-in-sq bottom longerons crosspiec es sheeting isnt trimmed off until Left Using front cabin bulkhead ass hg builder glues sides bottom sheeting against bottom side pieces Right assembled fuselage minus top sheeting Note sheet laminations nose Excess bottom sheeting trimmed off point construction technique ensures perfect centerline alignment tail Both Mk Mk II fuselages built same manner November 1990 85 sides top place Drawing centerline bottom sheet ing allows precise positioning rud der post After top longerons side crosspieces have glued fin ished sides fitted top bottom sheeting against bottom longerons Erect main cabin bulkheads before bend ing sides inward aft rear cabin sta tion Second lengths sheet balsa dimen sions given plan laminated graduate inward nose ring avoids awkward bending sides area forward cabin nose rough shaped sanding board progressing coarse medium paper Note different airfoil options re quire different fuselage top rails proper seating semisymmetrical section matching saddle necessitates deeper top rail allow required cutout Likewise choice nose wing op tions influences selection hold-down method consequently number location tapped hold-down blocks dow els etc Tail surfaces selection tail type de termines shape saddle bottom-mounted stabilizer MK built-up stab has cross section basically like two triangles set base base spar position Dress cross section precise contour sanding board sloping edges match shal low triangular shapes beveling edges flat spars Hold sanding Bill Evans showing off trademarks small external aileron servos Bill Winter impressed simplicity now has several models board steadily against edge spar youre working Finish moving board about gradually taking down mate rial along span rather anchoring spot Bolt-on stab mounting recommended easy transportation compact car either tail option epoxied place cer tain remove covering wood-towood joints includes covering laps around bottom saddle assembling vertical surfaces caution trial fit rudder tiller arm allowing sufficient space swing freely prevent metal-to-metal contacts thin neoprene tubing forced over tiller passed through rudder-mounted sheet metal bracket ac cepts tiller align independent finone isnt integral stabclamp thin straightedge hard straight flat piece wood cabin top aligned center marks Bend straightedge wood strip down centerline hole made tiller arm Draw guideline re move strip Evans cut MK II stab light weight foam two tapered halves butt joined centerline after being skinned A6 sheet balsa used own twosided Core Film tape attach skinning Its easy apply works well doesnt lift balsa skin Evans also used own X-Hingeslong sewn hinge strips cut length ironed close hinge gap accept MonoKote well Note leading edge spar glued foam slabs Use yellow glue similar adhesive Sand edges matching contour first achieving flat sloped surface sheeting will glued later rounding off full leading edge Evans glued stab place pre fer bolt yours sure reinforce bolt holes between top bottom sheet ing adequate quantity balsa stalled grain runs vertically Bolts will crush unsupported foam must done prior skinning Adhesives view differences ma terials between two Krackerjac ver sions few notes order wide variety glues can used balsato-balsa joints both authors used Hot Stuff instant well slow-setting because shortens building time Winter finds 3M spray-can contact cement suitable lami nating nose block sheets Epoxy used firewalls wing joiners though Win ter used white glue joiners openframe wing Both Evans Winter used two-sided Core Film skinning Contact cement may substituted make sure its com patible foam 3M spray can vari ety helps job go quickly White glue used attach balsa edge pieces foam cores Winter pro tects inside surfaces nose cavity 86 Model Aviation Above Bill Evans making slow flyby Mk ii Krackerjac crystal-clear air Bishop CA high-performance version equipped OS 60 two-stroke has ailerons rigged fiapperons Look closely youll notice flaps partially deployed Below closer look Mk ii fiapperons clearly visible model has balsaskinned foam core wing stabilizer no spoilers Winter %-1A French-curve airfoil two coats thinned epoxy Landing gear Any standard metal gear satisfactory Halico gear appropri ate size 7A-lb plane bit flimsy anything good landing original Great Planes gear wider tougher Both legs gear bent slight toe-in angle Toe-in eliminates erratic takeoff runs thereby reducing corrections Planes pronounced torque swings will behave bet ter perfectly toe-in No two degrees both toe-in castor recommended standard gear can twisted angle large bench vise Attach gear either two A-in ny lon bolts fitted blind nuts four self-tapping screws nylon bolts will shear semicrash landing broken rem nants can removed heating tip screwdriver Klett plastic gear appeared af ter design produced medium size recommended MK wing open-frame wing can built spoilers men tioned Construction techniques will fa miliar builder experience undertake project nature long Phillips entry airfoil curve leading edge near spar position bottom has characteristics close semisymmetrical section flat portion aft spars makes easy assemble bench Though spacing blocks eliminated its advisable block up leading edge ensure align ment Use standard glue epoxy tach joiners spoilers used note spar webs area front spars clear spoiler horn plans show sizes align ment bellcranks linkage spoiler servo have different servo arm travel indicated plan compensate appropriate holes dont change horn spacing spoiler Washout MK wing achieved bottom-sanding board tip area indicated plan MK II wing Evans built wing foam skinned A6 balsa sheeting airfoil approximate A-2A semisymmetrical section set less incidence MK wing produces less angular difference between wing stab improves aer obatics higher speeds Again Core Film tape X-Hinges used Other hinges may substi tuted made Robart example strong easy usesimply bore holes insert hinges epoxy Since ailerons rather thick fash ion lightest possible balsa Construction differs somewhat used foam stab leading edge built two pieces inner pieces glued flat edge foam sanded before skinning aileron spar re ceives same treatment skinning ex tends over edges After skinning leading edge proper glued front wing Its depth equal inner lead ing edge plus thickness top bottom skins Evans joiner though built A-in ply shallower shown Since UPS performed ultimate stress test changed full-depth joiner shown cut depth foam wing /6 ply slot full-depth joiner easier cut saw tapered por tion joiner will leave gap slot close-up shot Mk Iis tail feathers shows short externai cievis rod runs devises middle hoies arge horns boit visible behind rud der horn retains tail wheei tiiler arm plans show bolt-on arrangement stabilizer its epoxied place plane can filled epoxied scrap foam microballoons mixed epoxy installing two outboard servos wing bottom Evans threaded servo leads through short paper tube buried foam wing before skinning An optional standard single-servo installa tion shown requires servo cavity wood mounting pieces built after skinning panel joining completed November 1990 87 Bill Winter didnt have force smile photo just completed tower ing perfectly round loop half throttle holding gentle stick pressure corrections first flight Evans high-performance Mk ii business end Evans Mk Ii Its OS 60 swinging 11 x 7 Zinger prop simple open-nose configuration shown option plans profile less deep Winters Mk version windshield carved block balsa Vertical-grain blocks un der two wing hold-down bolts prevent crushing foam wing skin Note ex haust diverter made copper plumbing elbow retained common hose clamp Block up panel turn proper dihedral aligning wing root edge workbench sanding board can used smooth matching root sections Some foam removed ac commodate smaller front rear join ers Trial fit panels joiners until fit perfect Before permanently inserting joiners work epoxy evenly slots smooth evenly over joiners Cover center joints M-oz glass cloth Attach cloth epoxy rubbing out excess outer edges wiping off residue wing tips sloped sanding board Make plywood jig piece check ing proper angle tips made soft sheeting overlap top bottom skin leave excess Block sand match wing top bottom Covering Though iron-on coverings easy use recommend textured mate rial MK companies sell dif ferent varieties often can painted MK used silk/rayon applied buty rate fuselage finished two coats K&B epoxy paint wings tail however covered Super Mono Kote Though excellent popular prod uct turned out unsuitable large-area open-frame wing ship size weight landing made considerable vertical impact during spoiler experiments MK dead weight wings flexed down structural damage split covering chordwise edge edge Covering sheeted fuselage A-oz glass cloth attached K&B satin brush ing epoxy provides strength good finish imperviousness raw fuel glass cloth brushes out flat pulling follows curves corners After allow ing stand overnight can sanded beautifully fine-grade paper given second coat K&B epoxy col ored paint wont leave trace brush mark single coat works well two sufficient Other material re quired open stab wing Super MonoKote worked well MK II its wing being solid rather openframe construction Evans loves effect orange accented dark blue striping MK has red fuselage orange wings stab silver vertical red-orange combination happenstance Winter 25-ft roll orange hand Yellow would make less fiery contrast red background Flying Anyone building mod els already knows flyor should notes follow intended famil iarize handling characteristics Winters Evans modelsa preflight handoff speak primary focus MK Since MK intended fly wing power spectacular vertical maneuvers high-rate rolls expected craft wasnt designed per form knife-edge categoryresponses realistic stick pressures pilot MK delivers some nice performance indeed Pilots full-size air planes will sense familiar feedback fact flying model rather like being cockpit aircraft does would expect Because flies wing Mark will surprise certain modes course vertical performance would improve 60 engine much power would disadvantage other re spects bigger engine would have throttled back considerably time using high power climb ma neuvers full power heavy down trim would required due lift available would need either fly backstick remove considerable down trim dur ing approaches landings K&B 40 MK lifts off one-third power out pilots touching elevator theres no need two-thirds throttle point Incidentally 10 x 6 pro peller usual choice 11 x 5 wood prop better matched models aero batics proper center-of-gravity CG loca tion flat-bottomed airfoil section 25% chord Though pilots ac customed trimming 33% requires down trim cruising heavier control deflections inverted outside loops forward position gives solid feeling better penetration less bouncing around wind light wing load ings ride bumpily wind Approaches positive groove good test appropriateness CG location aerobatics perform outside loop constant elevator power ship buttonhooksthat tightens up during last quarter maneuver straightens back level flight lower its original altitudethis means its too nose-heavy Because model both short-coupled tail-dragger full up elevator recom mended slow taxiing grassespe cially grass long ragged begin takeoff advance throttle slowly smoothlynever abruptlywhile continu ing hold up elevator short distance typically 10 ft Actually lower power Continued page 196 88 Model Aviation Bill Evans baisa4kinned foam-core Mk ii wings root left has yet slotted joiner pians shows fuii-depth joiner requiring presiotting foam Evens inserts deep joiner through bottom slot including bottom skin cutout wing tip right msde soft sheet balsa cut oversize sanded flush top bottom sheeting foam-core stabilizer halves Evans Mk ii have skinned balsa sheeting ready joined center epoxy tips made sheet balsa --- * fl5 E Main Northvlfle Ml 481 67 Special Fast Turnaround Now Available CALL Frequency Conversion $4000 Includes Crystals Certification Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royai Tower HobbiesWorld Engines Spectrum Ana lyzers Cali brated Test struments Large Inventory R/C Parts Crystals Self I Addressed Envelope Ill Fly What Fix LeI ZAP UNIVERSITY COLLEGE OF GLUE KNOWLEDGE turn use small medical syringe meter fuel engine Cardinal will fly out sight full tank measuring fuel important Limit first test flights short engine runs five seconds stretching long practical ie long care run af ter model once things look safe Normally start priming engine hooking up battery Once prime fuel left tank run out feed measured amount check wind direc tion start engine needle valve preset produce slow run once its running its time launch its gusty day Cardinal probably ready its trim dihedral model will handle fair amount wind Make sure shes launched directly wind just slightly off right Sport flying should always much fun Krackerjac/Wi nter-Evans Continued page 90 used begin roll followed smooth steady advancing throt tle pilot wont need bold up take off allowing roll develop bit before going higher power increase airspeed point rudder has good bite steering tail-dragger steering control low speeds derives tail wheel much rud der quick surge power allowed lift tail instantly airplane will lose steering power due loss tail wheel trac tion 5-mph headwind MK will climb quickly landing pattern height one-third power power expect airplane climb rapidly fly wing two degrees dihedral permits free flight hands-off stability yielding continu ous turns either aileron rudder out compromising wingovers etc stooging around wide turns can tight ened much desired touch up el evator nose wont drop return neutral roll out plane will nose-up invert MK raise nose slightly say 100 half roll al lows time feel matching down el evator before nose drops Powered 40 engine model will sustain invert ed maneuversincluding steering figure eights etcat two-thirds power one-half going down no two-thirds go ing down circumstances Three consecutive concentric outside loops can done flying off top half power one-third one-half go ing down power speed opens up outside increasing loadings up side possibly causing twisting out ship has area thats intended used Landing approaches long airUPS US Mail Federal Express OOD Mastercard Visa Acce ted YOU WONT GET STUNG ON OUR NEW STINGER ARF Fuselage Length 525 Wing Span 84 Rec Engine Size 12 42 cu inArea 1596 sq Flying Weight 14 lbs & upRadio Channels 4 Available favorite Hobby Dealer Replacement parts available Dealer distributor inquiries invited Write today information LANIER RC PO Box 458 ood GA 30566 532-6401 Made U S 196 Model Aviation LISTED FORACOMPLETh PLEASE SEND STAMPED SELF-AL mSAATL FOR YOUR BUSINESS _____I~\I plane shows surprising ability keep coming makes really good idle essen tial bigger lower pitched prop provides bit braking Because clean ap proach use stick pressure rather movements up elevator begin flareotherwise youll go out other side Slowly build up sink touchdown gradually increasing up pressure As mentioned ship soars easily has soared out turn cross wind adding power simply trim ming rudder flat wide circles Nor mally soaring MK done climb ing moderate glide altitude going notch above idle trimming rud der continuous flat circles lift cir cle tightens speed increases go idle shut off model becomes Glid er Dress circle diameters rudder trim locked model will bank steeply go automatic Its easy see spoilers added MK though theyre optional small front-hinged spoilers typi cal blade types designed put Sail plane ground will kill some lift minimum buildup drag MK spoilers set full-open posi tion 60% vertical effect requires steady compensation up elevator goaround aborted landing possible spoilers less full power Use proportional channel radio spoilers can opened degree de sired spoiler system designed produce dethermalized descent Free Flight style thats variable slight limited full Compensating up elevator varies amount spoiler applied model can hold increasing nose-up attitude augment sink desired point STOL descent chooses Its possible fully open spoilers land ing pattern power downwind arriv ing 50 ft high just 100 ft short runway go idle STOL down head runwayor exit thermals approach 600 flight path high altitude anywhere easily hit spot spoiler action limited enough allow final flare safety tech niques fully described Winters arti cle Spoilers Power Febru ary 1986 Model Aviation flying habits MK II dont re quire special description can build youll know what MK II excels close-in maneuvers allowing nervous pilot enough reaction time prevent ships getting ahead him Due airfoil type angular rig ging spoilers appropriate gentlest headwind either model will fly ground cushion extremely low power pilot holds up elevator Winter claims has walked quickly beside MK pilot slows up too much final close ground both ships can stagger around like drunken sail ors until aileron response lost common VEND MOUNTSOn. 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Edition: Model Aviation - 1990/11
Page Numbers: 83, 84, 85, 86, 87, 88, 196, 197, 198
Krackerjac Mk Mk II favorite oddcouple design team backthis time two-for-one like options build RC sport plane/ trainer combo Mark soars delightfully its higher performance sibling gets excellent marks hot-dogging U Bill Winter Bill Evans VOICE OFFSTAGE go again opposite schools design coau thors have managed second last presumes unlikely collaboration West Coaster Evans loves straight-up 140 0-plus flybys known philoso phy horizontal tails tantamount buggy-whip technology East Coaster pre historic old-timer Bill Winter go-slow airplane watcher thinks straight-up folks harbor hidden rocketry complexes Still found middle ground pro duced Krackerjac MK II Asked Evans would stoop build ing conservative cabin job conspic uous stabilizer Winter would say Whats nice guy like Bill Evans doing place like two collaborated Simitar Slow Motion published January 1987 issue Model Aviation docile flying wing almost easy fly Eaglet time Winters responsiveness Simitar proj ect flabbergasted Evans Winter ever did impose certain conditions First model soarso speed range set 15 80 mph plane fully controllable either rudder aileronsso equipped elevons Because specifications fuselage behind bobtail trailing edge termination extended some eight inches rudder post Since Winter also demanded extended pe riods hands-off flying modest dihedral added Indeed Slow Motion would 720s hands-off initial tap aileron stick save weight ship Krackerjac Mark pictured before its first flight flown Bill Winter couple years before being modified installing spoilers 6-ft-span 40-powered ship has wings stabilizer open-frame construction airfoil thin flat bottomed up main spar has long Phillips entry model has over 6 sq ft area under 19-ozIsq-ft loading will soar easily weak thermals airplane takes off climbs out 1A throttle will consecutive outside loops ttle fly about verted % throttle Bill added spoilers landings could easily made short flying fields Mk Bill Winters newest version Krackerjac seen doing what Bill likes besta slow flyby low altitude low throttle Model can equipped spoilers much like Thermal Soarers help control landings lightly loaded ship Tom Schmitt photo November 1990 83 little headwind model will tly ground cushion extremely low throttle Win ter claims times has able walk quickly beside model still airborne Mk floating its wheels just above grass Tom Schmitt photo tail-dragger protect old man Evans added foot span Aerobatic capability must K&B Veco 19 maximum power after adding second foot span bringing model six feet using 05 15 power performance essentially un changed did Evans Winter join gether second time Krackerjac Winter In 1960 good systems fullhouse control around about five years us could afford single-channel escapement airplanes Lacking elevator control designs addicted ballooning turns wind fly-aways commonplace original 54-in model called K rudder-only control quick-blip high/low throttle Max 15 ended non sense plane published Air Trails kitted Jetco Incidentally throttles time used exhaust stack re strictor coupled butterfly ven turi thin airfoil long Phillips en try secret models controlla bility original handled like multi llent penetration facility per fect touch-and-goes RCs over 40-year period three continue built Antique RC Special published 1948 early-60s Krackerjac reed-systems low-wing Rookie first published Model Airplane News early Sixties later some what modified publication Model Builder Other modelers have frequently im proved upon designs continue Several years ago obtained 6-ft ver sion Krackerjac 40 power plans service built model dozen test flights magazine ex pressed desire publish major manufacturer asked about kit mag wanted perfect pictures unfortu nately Id already marred covering stall spoilers wing efficient 6 sq ft 7A lb gross weight like Glider difficult get ground 300-ft strip Krackerjac soared ease dis covered day turning cross wind leg sixth flight noted no loss altitude did 360 ended up clouds Equipped 40 model demon strated considerable prowess took off climbed one-third throttle could fly inverted respond steering half throttle performed consecutive outside loops half throttle one-third down el evator Yet magazine staff thought plane should have 120 Hard believe told kit company opinion Krackerjac wasnt mainstream hence its best interests aircraft eventually given Doug Pratt converted K&B 40 to Enya four-stroke 46 Pratt has flown three seasons happened mention Bill Evans adding could get clean photos thought should published Evans Curiosity killed cat though find horizontal tails useless appendages Winters strange short-coupled cabin its big stab bottom odd appeal could build onemy way youll seeand fly within week Winter sent print Finding untried modification using semisymmetri cal airfoil 60 power phoned him ask Which would like build said might check out never-built aerobatic version Winter uses lots sticks Im always hurry So simplified fuse went foam balsa-skinned wing stab isnt neutrally stable prefer Winter wont give up measure hands-off control otherwise flies great Winter able join California watching pleased expressions flew per formance version treasured moments Ill never live down project has tail Everybody fly visits shop ribs unmercifully too much shipped model Winter year later Alas reports UPS stress tested wing found wanting Winter So now two airplanes different performance envelope working plan original good new pictures Evans Attempts revise original print tracer ran stone wall project sat 15 months Evans Dont ever get mixed up hair-splitting old-timers Theyll drive up wall kept asking Winter Whats problem Air Force project overruns delays would have provoked Congress hed draw wed done week Finally badgered him drawing incorporating sup plementary drawings decided show cross-options stuff crammed plans could come up least four differ ent ships Maybe should have sold National Geographic Surprise editor gave him green light two 40 x 52-in sheets proposed Winter designate original Mark call Mark II added Buddy East Coast now its own Winter Which build what ex pect Marks Design objectives MK easy piloting rather like 40-powered Senior Falcon Sig Kadet Goldberg Ea gle ability groove well maneuvers better average aerobatics enough reaction time prevent airplanes getting ahead average pi lot slow landings automatic takeoff though its tail-dragger ability ride weak general lift thermal soar Fly 84 Model Aviation close-up shot shows some details Mk built-up wing spoilers shown partially deployed control servos visible under transparent wing covering Steve Kaluf demonstrates short landing tech niques using spoilers plane will land observed attitude reserve flare can abort spoilers deployed Specs spoilers Size opening location etc shown plans tailored safe flight envelope ing techniques discussed end article low wing loading 19 ozI sq ft low drag result consistent ma chine sustains open maneuvers rela tively low power hands-off stability makes relaxed flying What about bigger engine Except improved vertical maneuvers brings added power self-defeating case 60 two-stroke limit youll find yourself doing aerobatics half power potent four-stroke such Enya 60 plenty Watch center-of-gravity such heavy engine An Enya 46 fourstroke does aerobatic maneuvers except advanced such knife-edge flight careful building can achieve gross weight seven pounds Mine turned out 7 lb spoilers two extra servos Some may come 8 lb because some always Dont load up paint Since ship can soar its lightly loaded large wing being equiv alent lower loading smaller wing has significantly higher Reynolds number long low approaches neces saryand critical small field obstacles beneath approach path may overshoot 300-ft strip model too high and/or too fast may wish consider spoiler option Spoilers allow make higher approaches land within first half strip Used front-hinge did create another fun mode flying described later MK Ls open-frame wing thin well large area heavy-handed pilot using oversized engine might overstress model example dive followed abrupt pullout overapplica tion up Evans MK H Winter specified airfoil incidence power 60 en gine version faster far Mark Its also spectacular groovy its closer being neutrally stable MK airplane still safe fly hands-off Winter said wanted two degrees dihedral own insur ance fuselage sides bottom shaped framed prepared ammbly ply gear plate place corner pieces will rounded later cross pIeces glued untrimmed bottom sheet grain running lengthwise side crosspieces trimmed exactly fit Note fishtail butt loint side sheeting above stabilizer saddle docile aircraft rather different fast neutrally stable machines Im used Still found nice fly wrung out Winter California handed controls over him Its measure planes easy handling low-speed abilities cruising about half throttle Winter held light back-pressure steadily ex ecuting towering perfectly round beauti ful loopall touching controls including throttle downside model seemed rails Throughout flight OS 60 gave him power wanted Very slight back trim slower stooging around resulted prolonged slight climb 2A-/3 airfoil ship will climb one-third throttle 60 foam wing balsa skin weighs ex actly same Winters open-frame MK wingfor total model weight 7 lb model robust enough kind flying wing thicker thing increased performance MK H can flown safely anyone aileron experience Like MK will fly ruddernice know since very slow approach rudder last control fail normal aircraft As shown used two exterior-mounted small Futaba servos ailerons Ive used arrangement de signs because its simple speeds up building Winter shocked first saw quickly agreed good way go now has same setup low-wing Desperado Simitar deriva tive anhedral wing reports no trace exhaust dirt servos Winter plans details op tions shown consider before making final decision MK presented basically com plete optional spoilers shown Though spoilers bring interesting dimen sion flying theyre required Cross sections outlines shown MK II wing tail Two versions wing shown Mine slightly modi fied two-bolt-and-dowel attachment Evans wing has four bolts panel can seen Evans external bottommounted servos linkage mod ified panel shows optional standard sin gle-servo arrangement Two profiles show mounting saddle semisymmetri cal wing near side view shows Evans reshaped cabin top four-bolt attachment other shows wing modified dowel two bolts Also shown Evans simpler open nose can substituted com plicated semi-enclosed nose MK Construction Fuselage Two techniques used ease assembly First bottom lies flat workbench Evans used length A-in soft sheeting grain running length wise bottom glued A-in-sq bottom longerons crosspiec es sheeting isnt trimmed off until Left Using front cabin bulkhead ass hg builder glues sides bottom sheeting against bottom side pieces Right assembled fuselage minus top sheeting Note sheet laminations nose Excess bottom sheeting trimmed off point construction technique ensures perfect centerline alignment tail Both Mk Mk II fuselages built same manner November 1990 85 sides top place Drawing centerline bottom sheet ing allows precise positioning rud der post After top longerons side crosspieces have glued fin ished sides fitted top bottom sheeting against bottom longerons Erect main cabin bulkheads before bend ing sides inward aft rear cabin sta tion Second lengths sheet balsa dimen sions given plan laminated graduate inward nose ring avoids awkward bending sides area forward cabin nose rough shaped sanding board progressing coarse medium paper Note different airfoil options re quire different fuselage top rails proper seating semisymmetrical section matching saddle necessitates deeper top rail allow required cutout Likewise choice nose wing op tions influences selection hold-down method consequently number location tapped hold-down blocks dow els etc Tail surfaces selection tail type de termines shape saddle bottom-mounted stabilizer MK built-up stab has cross section basically like two triangles set base base spar position Dress cross section precise contour sanding board sloping edges match shal low triangular shapes beveling edges flat spars Hold sanding Bill Evans showing off trademarks small external aileron servos Bill Winter impressed simplicity now has several models board steadily against edge spar youre working Finish moving board about gradually taking down mate rial along span rather anchoring spot Bolt-on stab mounting recommended easy transportation compact car either tail option epoxied place cer tain remove covering wood-towood joints includes covering laps around bottom saddle assembling vertical surfaces caution trial fit rudder tiller arm allowing sufficient space swing freely prevent metal-to-metal contacts thin neoprene tubing forced over tiller passed through rudder-mounted sheet metal bracket ac cepts tiller align independent finone isnt integral stabclamp thin straightedge hard straight flat piece wood cabin top aligned center marks Bend straightedge wood strip down centerline hole made tiller arm Draw guideline re move strip Evans cut MK II stab light weight foam two tapered halves butt joined centerline after being skinned A6 sheet balsa used own twosided Core Film tape attach skinning Its easy apply works well doesnt lift balsa skin Evans also used own X-Hingeslong sewn hinge strips cut length ironed close hinge gap accept MonoKote well Note leading edge spar glued foam slabs Use yellow glue similar adhesive Sand edges matching contour first achieving flat sloped surface sheeting will glued later rounding off full leading edge Evans glued stab place pre fer bolt yours sure reinforce bolt holes between top bottom sheet ing adequate quantity balsa stalled grain runs vertically Bolts will crush unsupported foam must done prior skinning Adhesives view differences ma terials between two Krackerjac ver sions few notes order wide variety glues can used balsato-balsa joints both authors used Hot Stuff instant well slow-setting because shortens building time Winter finds 3M spray-can contact cement suitable lami nating nose block sheets Epoxy used firewalls wing joiners though Win ter used white glue joiners openframe wing Both Evans Winter used two-sided Core Film skinning Contact cement may substituted make sure its com patible foam 3M spray can vari ety helps job go quickly White glue used attach balsa edge pieces foam cores Winter pro tects inside surfaces nose cavity 86 Model Aviation Above Bill Evans making slow flyby Mk ii Krackerjac crystal-clear air Bishop CA high-performance version equipped OS 60 two-stroke has ailerons rigged fiapperons Look closely youll notice flaps partially deployed Below closer look Mk ii fiapperons clearly visible model has balsaskinned foam core wing stabilizer no spoilers Winter %-1A French-curve airfoil two coats thinned epoxy Landing gear Any standard metal gear satisfactory Halico gear appropri ate size 7A-lb plane bit flimsy anything good landing original Great Planes gear wider tougher Both legs gear bent slight toe-in angle Toe-in eliminates erratic takeoff runs thereby reducing corrections Planes pronounced torque swings will behave bet ter perfectly toe-in No two degrees both toe-in castor recommended standard gear can twisted angle large bench vise Attach gear either two A-in ny lon bolts fitted blind nuts four self-tapping screws nylon bolts will shear semicrash landing broken rem nants can removed heating tip screwdriver Klett plastic gear appeared af ter design produced medium size recommended MK wing open-frame wing can built spoilers men tioned Construction techniques will fa miliar builder experience undertake project nature long Phillips entry airfoil curve leading edge near spar position bottom has characteristics close semisymmetrical section flat portion aft spars makes easy assemble bench Though spacing blocks eliminated its advisable block up leading edge ensure align ment Use standard glue epoxy tach joiners spoilers used note spar webs area front spars clear spoiler horn plans show sizes align ment bellcranks linkage spoiler servo have different servo arm travel indicated plan compensate appropriate holes dont change horn spacing spoiler Washout MK wing achieved bottom-sanding board tip area indicated plan MK II wing Evans built wing foam skinned A6 balsa sheeting airfoil approximate A-2A semisymmetrical section set less incidence MK wing produces less angular difference between wing stab improves aer obatics higher speeds Again Core Film tape X-Hinges used Other hinges may substi tuted made Robart example strong easy usesimply bore holes insert hinges epoxy Since ailerons rather thick fash ion lightest possible balsa Construction differs somewhat used foam stab leading edge built two pieces inner pieces glued flat edge foam sanded before skinning aileron spar re ceives same treatment skinning ex tends over edges After skinning leading edge proper glued front wing Its depth equal inner lead ing edge plus thickness top bottom skins Evans joiner though built A-in ply shallower shown Since UPS performed ultimate stress test changed full-depth joiner shown cut depth foam wing /6 ply slot full-depth joiner easier cut saw tapered por tion joiner will leave gap slot close-up shot Mk Iis tail feathers shows short externai cievis rod runs devises middle hoies arge horns boit visible behind rud der horn retains tail wheei tiiler arm plans show bolt-on arrangement stabilizer its epoxied place plane can filled epoxied scrap foam microballoons mixed epoxy installing two outboard servos wing bottom Evans threaded servo leads through short paper tube buried foam wing before skinning An optional standard single-servo installa tion shown requires servo cavity wood mounting pieces built after skinning panel joining completed November 1990 87 Bill Winter didnt have force smile photo just completed tower ing perfectly round loop half throttle holding gentle stick pressure corrections first flight Evans high-performance Mk ii business end Evans Mk Ii Its OS 60 swinging 11 x 7 Zinger prop simple open-nose configuration shown option plans profile less deep Winters Mk version windshield carved block balsa Vertical-grain blocks un der two wing hold-down bolts prevent crushing foam wing skin Note ex haust diverter made copper plumbing elbow retained common hose clamp Block up panel turn proper dihedral aligning wing root edge workbench sanding board can used smooth matching root sections Some foam removed ac commodate smaller front rear join ers Trial fit panels joiners until fit perfect Before permanently inserting joiners work epoxy evenly slots smooth evenly over joiners Cover center joints M-oz glass cloth Attach cloth epoxy rubbing out excess outer edges wiping off residue wing tips sloped sanding board Make plywood jig piece check ing proper angle tips made soft sheeting overlap top bottom skin leave excess Block sand match wing top bottom Covering Though iron-on coverings easy use recommend textured mate rial MK companies sell dif ferent varieties often can painted MK used silk/rayon applied buty rate fuselage finished two coats K&B epoxy paint wings tail however covered Super Mono Kote Though excellent popular prod uct turned out unsuitable large-area open-frame wing ship size weight landing made considerable vertical impact during spoiler experiments MK dead weight wings flexed down structural damage split covering chordwise edge edge Covering sheeted fuselage A-oz glass cloth attached K&B satin brush ing epoxy provides strength good finish imperviousness raw fuel glass cloth brushes out flat pulling follows curves corners After allow ing stand overnight can sanded beautifully fine-grade paper given second coat K&B epoxy col ored paint wont leave trace brush mark single coat works well two sufficient Other material re quired open stab wing Super MonoKote worked well MK II its wing being solid rather openframe construction Evans loves effect orange accented dark blue striping MK has red fuselage orange wings stab silver vertical red-orange combination happenstance Winter 25-ft roll orange hand Yellow would make less fiery contrast red background Flying Anyone building mod els already knows flyor should notes follow intended famil iarize handling characteristics Winters Evans modelsa preflight handoff speak primary focus MK Since MK intended fly wing power spectacular vertical maneuvers high-rate rolls expected craft wasnt designed per form knife-edge categoryresponses realistic stick pressures pilot MK delivers some nice performance indeed Pilots full-size air planes will sense familiar feedback fact flying model rather like being cockpit aircraft does would expect Because flies wing Mark will surprise certain modes course vertical performance would improve 60 engine much power would disadvantage other re spects bigger engine would have throttled back considerably time using high power climb ma neuvers full power heavy down trim would required due lift available would need either fly backstick remove considerable down trim dur ing approaches landings K&B 40 MK lifts off one-third power out pilots touching elevator theres no need two-thirds throttle point Incidentally 10 x 6 pro peller usual choice 11 x 5 wood prop better matched models aero batics proper center-of-gravity CG loca tion flat-bottomed airfoil section 25% chord Though pilots ac customed trimming 33% requires down trim cruising heavier control deflections inverted outside loops forward position gives solid feeling better penetration less bouncing around wind light wing load ings ride bumpily wind Approaches positive groove good test appropriateness CG location aerobatics perform outside loop constant elevator power ship buttonhooksthat tightens up during last quarter maneuver straightens back level flight lower its original altitudethis means its too nose-heavy Because model both short-coupled tail-dragger full up elevator recom mended slow taxiing grassespe cially grass long ragged begin takeoff advance throttle slowly smoothlynever abruptlywhile continu ing hold up elevator short distance typically 10 ft Actually lower power Continued page 196 88 Model Aviation Bill Evans baisa4kinned foam-core Mk ii wings root left has yet slotted joiner pians shows fuii-depth joiner requiring presiotting foam Evens inserts deep joiner through bottom slot including bottom skin cutout wing tip right msde soft sheet balsa cut oversize sanded flush top bottom sheeting foam-core stabilizer halves Evans Mk ii have skinned balsa sheeting ready joined center epoxy tips made sheet balsa --- * fl5 E Main Northvlfle Ml 481 67 Special Fast Turnaround Now Available CALL Frequency Conversion $4000 Includes Crystals Certification Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royai Tower HobbiesWorld Engines Spectrum Ana lyzers Cali brated Test struments Large Inventory R/C Parts Crystals Self I Addressed Envelope Ill Fly What Fix LeI ZAP UNIVERSITY COLLEGE OF GLUE KNOWLEDGE turn use small medical syringe meter fuel engine Cardinal will fly out sight full tank measuring fuel important Limit first test flights short engine runs five seconds stretching long practical ie long care run af ter model once things look safe Normally start priming engine hooking up battery Once prime fuel left tank run out feed measured amount check wind direc tion start engine needle valve preset produce slow run once its running its time launch its gusty day Cardinal probably ready its trim dihedral model will handle fair amount wind Make sure shes launched directly wind just slightly off right Sport flying should always much fun Krackerjac/Wi nter-Evans Continued page 90 used begin roll followed smooth steady advancing throt tle pilot wont need bold up take off allowing roll develop bit before going higher power increase airspeed point rudder has good bite steering tail-dragger steering control low speeds derives tail wheel much rud der quick surge power allowed lift tail instantly airplane will lose steering power due loss tail wheel trac tion 5-mph headwind MK will climb quickly landing pattern height one-third power power expect airplane climb rapidly fly wing two degrees dihedral permits free flight hands-off stability yielding continu ous turns either aileron rudder out compromising wingovers etc stooging around wide turns can tight ened much desired touch up el evator nose wont drop return neutral roll out plane will nose-up invert MK raise nose slightly say 100 half roll al lows time feel matching down el evator before nose drops Powered 40 engine model will sustain invert ed maneuversincluding steering figure eights etcat two-thirds power one-half going down no two-thirds go ing down circumstances Three consecutive concentric outside loops can done flying off top half power one-third one-half go ing down power speed opens up outside increasing loadings up side possibly causing twisting out ship has area thats intended used Landing approaches long airUPS US Mail Federal Express OOD Mastercard Visa Acce ted YOU WONT GET STUNG ON OUR NEW STINGER ARF Fuselage Length 525 Wing Span 84 Rec Engine Size 12 42 cu inArea 1596 sq Flying Weight 14 lbs & upRadio Channels 4 Available favorite Hobby Dealer Replacement parts available Dealer distributor inquiries invited Write today information LANIER RC PO Box 458 ood GA 30566 532-6401 Made U S 196 Model Aviation LISTED FORACOMPLETh PLEASE SEND STAMPED SELF-AL mSAATL FOR YOUR BUSINESS _____I~\I plane shows surprising ability keep coming makes really good idle essen tial bigger lower pitched prop provides bit braking Because clean ap proach use stick pressure rather movements up elevator begin flareotherwise youll go out other side Slowly build up sink touchdown gradually increasing up pressure As mentioned ship soars easily has soared out turn cross wind adding power simply trim ming rudder flat wide circles Nor mally soaring MK done climb ing moderate glide altitude going notch above idle trimming rud der continuous flat circles lift cir cle tightens speed increases go idle shut off model becomes Glid er Dress circle diameters rudder trim locked model will bank steeply go automatic Its easy see spoilers added MK though theyre optional small front-hinged spoilers typi cal blade types designed put Sail plane ground will kill some lift minimum buildup drag MK spoilers set full-open posi tion 60% vertical effect requires steady compensation up elevator goaround aborted landing possible spoilers less full power Use proportional channel radio spoilers can opened degree de sired spoiler system designed produce dethermalized descent Free Flight style thats variable slight limited full Compensating up elevator varies amount spoiler applied model can hold increasing nose-up attitude augment sink desired point STOL descent chooses Its possible fully open spoilers land ing pattern power downwind arriv ing 50 ft high just 100 ft short runway go idle STOL down head runwayor exit thermals approach 600 flight path high altitude anywhere easily hit spot spoiler action limited enough allow final flare safety tech niques fully described Winters arti cle Spoilers Power Febru ary 1986 Model Aviation flying habits MK II dont re quire special description can build youll know what MK II excels close-in maneuvers allowing nervous pilot enough reaction time prevent ships getting ahead him Due airfoil type angular rig ging spoilers appropriate gentlest headwind either model will fly ground cushion extremely low power pilot holds up elevator Winter claims has walked quickly beside MK pilot slows up too much final close ground both ships can stagger around like drunken sail ors until aileron response lost common VEND MOUNTSOn. THE VIBRATION KILLERRubber ft Engine Power Free Flight Display Fail fuel poot In. axes jaolaton 25 00 engine..eo .Control Line Electric Power RIC Airplanes File aCtually tiloWalt angIna'"Our new illustrated 32 page tabloid size catalog mounts Typical oibationtduction TOT, tae85%Tt 01 OOneieteOfUS ft Canada *100 Foreigli $300 moultIS salute four POints 0002ndt'l nn Valley Hobby center washers tubing inStruCtIOnS Sand Sf200 Otrena non Order837-A W Main St Lanadale PA 19448 000 kit GSA PRODUCTS PC 800 3602$ SARASOTA FL 34233 StOOar 3684770 3774252 FL residnts add 72% SaleS faa IRFO5MATIOR sand SASS THE KOMBAT 40 - GREAT R/C SPORT AFPLANE AND WITH SO LITTLE TIME AND MONEY INVESTED YOU CAN REALLY HAVE BALL iTS FULLY AEROBATIC AND EXTREPRELY DURABLE CONSTRUCTED OF ALUtvtIUM AND RUBBERIZED PLASTIC YOU PROVDE THE RADIO AND ENGINE WE SUPPLY EVERYTHING ELSE NO EXTRAS TO BUY 25 ENGINE MAKES GREAT ADVANCED TRAINER SPECIAL INTRODUCTORY OFFER 5 POSTPAID LIST $8995 1880 PINEVIEW MANDEVILLE LA 70448 November 1990 197 620 CRANDALL-LANESVILLE RD CORYDON INDIANA 471 LARGE SELECTION OF REMOTE CONTROL MODEL AIRPLANES AND ACCESSORIES FOR THE PROFESSIONAL A-J US TO JIG AMBROID ARCO RUBBER BANDS BRIDI DA VEYS SYSTEMS CHAMPION CO yE RITE DEVCON SIG SONIC-TRONICS STERLING SULLIVAN TOP FLITE YS ENGINES ZINGER PROPS FK art fiberglass fuSel MADE IN USA PHONE ORDERS 504 626-7840 1-8002647840 SATISFACTION GUARANTEED FLYABLE IN ONE HOUR 1EdiTT FOR ORDERS ONLYJLr7TY 1 -8OO633-7556CODs IN ALABAMA 3473525 COLLECTWELCOME TOP QUALITY FUEL FOR EXPERT OR BEGINNER NO RE-CLAIMED ALCOHOL O METHANE ONLY IS USED Designed tested give top performance both 2 cycle 4-cycle engines ringed Except engines requiring low lubricant content CONTAINS NEW TRULY SPACE AGE ADDITIVE ha deve oped nan outer space vacuum new additive attaches internal metal parts ot engine will reduce nc much 80 reduces heat wear absolute minimum WE HAVE 3 LUBRICANT BLENDS ALL SYNTHETIC OR SYNTHETIC BLEND CASTOR lOur castor new h gh Pu y much c eaner burning castor ALL OUR FUELS CONTAIN ANTIFOAMERS PREVENTERS WEAR ADDITIVES tuel developed priced nd v dus c ub d ect sales market dealer inquiries invited Ord gailon up Mis OK i 4 gailon cases up ALL FUEL EXCEPT 54 GALLON DRUMS SHIPPED FREIGHT PRE-PAID Oniy Coniinentsi USA fTo 3 GalI 23051jTo 63 GaiITO 127 Gal/ Up / Freight Collects 1 Gal4 Gal 24 Gat~64 Gal I28 Gait 54 Gal Drum 50/ 1095 0065057518500 12/1495. 95090085077528000 25%1995 1450 400 1350 1275 47500 50% 2695 22 50 2200 2075 78000 Manufactured MACH-7 PO Box 1201 Enterprise Alabama 36330 condition can landed rud-touch down withtn foot white dot der reassuring know rudder willMiracle Landing/Jollythe runway camera zooming hold heading goof go-roundContinued page 104 tight realism youre sort modeler must Mile Square wasnt closed way have fireworks build standard Stik alibbed walked away epoxyssince flying off adjacent runway piped 60 its realistic enjoyment thatnot holding up Once lower stan-under tightly controlled conditions Sport want either Krackerjacs isdards Krylon model will last for-flying continued active runway pleasant own flyeverthere no lack interested helpers paradox proved true theEach 12 flights last day Epilogue Evans shipped MK IIday 737 made see dif-picture perfect Kent would light fires Winter stab detached itficult shots wed asked like fly-and plane would accelerate lift off taped note Leave off fliesing over edge runway three feetfly Steve Korney tracked 737 over better Winters comment Ifabove ground came off hitch80 mph gear-down over 90 mph gearEvans isnt spoofing would have used ai-Imagine foam glass Krylonup literally stopped traffic nearby lerons elevons reflexed upwardscooting along 80-mph-plus over thestreets drivers spotted what appeared ral control CG atsame ground track time after time Thenbe stricken airliner landing Mile Square 20% Enough alreadythere landings model Continued page 200 PRODUCTS Complete Line Exhaust Systems Tuned Muffled Tuned Pipes Headers uri Mufflers Expansion Mufflers copter Ball Mufflers ialized Exhaust Systems Unsupassed Workmanshin B Paiformance 198 Model Aviation TulnkflvCosnWed Shotioq 1/4 Scale Kits $12995 Epoxy/Glass/Foam Construction Drawings Data Formula 120 Pylon Sport Standoff ScaleKit Price ping Credit Cards WelcomedOhio Residents Add 7%
Edition: Model Aviation - 1990/11
Page Numbers: 83, 84, 85, 86, 87, 88, 196, 197, 198
Krackerjac Mk Mk II favorite oddcouple design team backthis time two-for-one like options build RC sport plane/ trainer combo Mark soars delightfully its higher performance sibling gets excellent marks hot-dogging U Bill Winter Bill Evans VOICE OFFSTAGE go again opposite schools design coau thors have managed second last presumes unlikely collaboration West Coaster Evans loves straight-up 140 0-plus flybys known philoso phy horizontal tails tantamount buggy-whip technology East Coaster pre historic old-timer Bill Winter go-slow airplane watcher thinks straight-up folks harbor hidden rocketry complexes Still found middle ground pro duced Krackerjac MK II Asked Evans would stoop build ing conservative cabin job conspic uous stabilizer Winter would say Whats nice guy like Bill Evans doing place like two collaborated Simitar Slow Motion published January 1987 issue Model Aviation docile flying wing almost easy fly Eaglet time Winters responsiveness Simitar proj ect flabbergasted Evans Winter ever did impose certain conditions First model soarso speed range set 15 80 mph plane fully controllable either rudder aileronsso equipped elevons Because specifications fuselage behind bobtail trailing edge termination extended some eight inches rudder post Since Winter also demanded extended pe riods hands-off flying modest dihedral added Indeed Slow Motion would 720s hands-off initial tap aileron stick save weight ship Krackerjac Mark pictured before its first flight flown Bill Winter couple years before being modified installing spoilers 6-ft-span 40-powered ship has wings stabilizer open-frame construction airfoil thin flat bottomed up main spar has long Phillips entry model has over 6 sq ft area under 19-ozIsq-ft loading will soar easily weak thermals airplane takes off climbs out 1A throttle will consecutive outside loops ttle fly about verted % throttle Bill added spoilers landings could easily made short flying fields Mk Bill Winters newest version Krackerjac seen doing what Bill likes besta slow flyby low altitude low throttle Model can equipped spoilers much like Thermal Soarers help control landings lightly loaded ship Tom Schmitt photo November 1990 83 little headwind model will tly ground cushion extremely low throttle Win ter claims times has able walk quickly beside model still airborne Mk floating its wheels just above grass Tom Schmitt photo tail-dragger protect old man Evans added foot span Aerobatic capability must K&B Veco 19 maximum power after adding second foot span bringing model six feet using 05 15 power performance essentially un changed did Evans Winter join gether second time Krackerjac Winter In 1960 good systems fullhouse control around about five years us could afford single-channel escapement airplanes Lacking elevator control designs addicted ballooning turns wind fly-aways commonplace original 54-in model called K rudder-only control quick-blip high/low throttle Max 15 ended non sense plane published Air Trails kitted Jetco Incidentally throttles time used exhaust stack re strictor coupled butterfly ven turi thin airfoil long Phillips en try secret models controlla bility original handled like multi llent penetration facility per fect touch-and-goes RCs over 40-year period three continue built Antique RC Special published 1948 early-60s Krackerjac reed-systems low-wing Rookie first published Model Airplane News early Sixties later some what modified publication Model Builder Other modelers have frequently im proved upon designs continue Several years ago obtained 6-ft ver sion Krackerjac 40 power plans service built model dozen test flights magazine ex pressed desire publish major manufacturer asked about kit mag wanted perfect pictures unfortu nately Id already marred covering stall spoilers wing efficient 6 sq ft 7A lb gross weight like Glider difficult get ground 300-ft strip Krackerjac soared ease dis covered day turning cross wind leg sixth flight noted no loss altitude did 360 ended up clouds Equipped 40 model demon strated considerable prowess took off climbed one-third throttle could fly inverted respond steering half throttle performed consecutive outside loops half throttle one-third down el evator Yet magazine staff thought plane should have 120 Hard believe told kit company opinion Krackerjac wasnt mainstream hence its best interests aircraft eventually given Doug Pratt converted K&B 40 to Enya four-stroke 46 Pratt has flown three seasons happened mention Bill Evans adding could get clean photos thought should published Evans Curiosity killed cat though find horizontal tails useless appendages Winters strange short-coupled cabin its big stab bottom odd appeal could build onemy way youll seeand fly within week Winter sent print Finding untried modification using semisymmetri cal airfoil 60 power phoned him ask Which would like build said might check out never-built aerobatic version Winter uses lots sticks Im always hurry So simplified fuse went foam balsa-skinned wing stab isnt neutrally stable prefer Winter wont give up measure hands-off control otherwise flies great Winter able join California watching pleased expressions flew per formance version treasured moments Ill never live down project has tail Everybody fly visits shop ribs unmercifully too much shipped model Winter year later Alas reports UPS stress tested wing found wanting Winter So now two airplanes different performance envelope working plan original good new pictures Evans Attempts revise original print tracer ran stone wall project sat 15 months Evans Dont ever get mixed up hair-splitting old-timers Theyll drive up wall kept asking Winter Whats problem Air Force project overruns delays would have provoked Congress hed draw wed done week Finally badgered him drawing incorporating sup plementary drawings decided show cross-options stuff crammed plans could come up least four differ ent ships Maybe should have sold National Geographic Surprise editor gave him green light two 40 x 52-in sheets proposed Winter designate original Mark call Mark II added Buddy East Coast now its own Winter Which build what ex pect Marks Design objectives MK easy piloting rather like 40-powered Senior Falcon Sig Kadet Goldberg Ea gle ability groove well maneuvers better average aerobatics enough reaction time prevent airplanes getting ahead average pi lot slow landings automatic takeoff though its tail-dragger ability ride weak general lift thermal soar Fly 84 Model Aviation close-up shot shows some details Mk built-up wing spoilers shown partially deployed control servos visible under transparent wing covering Steve Kaluf demonstrates short landing tech niques using spoilers plane will land observed attitude reserve flare can abort spoilers deployed Specs spoilers Size opening location etc shown plans tailored safe flight envelope ing techniques discussed end article low wing loading 19 ozI sq ft low drag result consistent ma chine sustains open maneuvers rela tively low power hands-off stability makes relaxed flying What about bigger engine Except improved vertical maneuvers brings added power self-defeating case 60 two-stroke limit youll find yourself doing aerobatics half power potent four-stroke such Enya 60 plenty Watch center-of-gravity such heavy engine An Enya 46 fourstroke does aerobatic maneuvers except advanced such knife-edge flight careful building can achieve gross weight seven pounds Mine turned out 7 lb spoilers two extra servos Some may come 8 lb because some always Dont load up paint Since ship can soar its lightly loaded large wing being equiv alent lower loading smaller wing has significantly higher Reynolds number long low approaches neces saryand critical small field obstacles beneath approach path may overshoot 300-ft strip model too high and/or too fast may wish consider spoiler option Spoilers allow make higher approaches land within first half strip Used front-hinge did create another fun mode flying described later MK Ls open-frame wing thin well large area heavy-handed pilot using oversized engine might overstress model example dive followed abrupt pullout overapplica tion up Evans MK H Winter specified airfoil incidence power 60 en gine version faster far Mark Its also spectacular groovy its closer being neutrally stable MK airplane still safe fly hands-off Winter said wanted two degrees dihedral own insur ance fuselage sides bottom shaped framed prepared ammbly ply gear plate place corner pieces will rounded later cross pIeces glued untrimmed bottom sheet grain running lengthwise side crosspieces trimmed exactly fit Note fishtail butt loint side sheeting above stabilizer saddle docile aircraft rather different fast neutrally stable machines Im used Still found nice fly wrung out Winter California handed controls over him Its measure planes easy handling low-speed abilities cruising about half throttle Winter held light back-pressure steadily ex ecuting towering perfectly round beauti ful loopall touching controls including throttle downside model seemed rails Throughout flight OS 60 gave him power wanted Very slight back trim slower stooging around resulted prolonged slight climb 2A-/3 airfoil ship will climb one-third throttle 60 foam wing balsa skin weighs ex actly same Winters open-frame MK wingfor total model weight 7 lb model robust enough kind flying wing thicker thing increased performance MK H can flown safely anyone aileron experience Like MK will fly ruddernice know since very slow approach rudder last control fail normal aircraft As shown used two exterior-mounted small Futaba servos ailerons Ive used arrangement de signs because its simple speeds up building Winter shocked first saw quickly agreed good way go now has same setup low-wing Desperado Simitar deriva tive anhedral wing reports no trace exhaust dirt servos Winter plans details op tions shown consider before making final decision MK presented basically com plete optional spoilers shown Though spoilers bring interesting dimen sion flying theyre required Cross sections outlines shown MK II wing tail Two versions wing shown Mine slightly modi fied two-bolt-and-dowel attachment Evans wing has four bolts panel can seen Evans external bottommounted servos linkage mod ified panel shows optional standard sin gle-servo arrangement Two profiles show mounting saddle semisymmetri cal wing near side view shows Evans reshaped cabin top four-bolt attachment other shows wing modified dowel two bolts Also shown Evans simpler open nose can substituted com plicated semi-enclosed nose MK Construction Fuselage Two techniques used ease assembly First bottom lies flat workbench Evans used length A-in soft sheeting grain running length wise bottom glued A-in-sq bottom longerons crosspiec es sheeting isnt trimmed off until Left Using front cabin bulkhead ass hg builder glues sides bottom sheeting against bottom side pieces Right assembled fuselage minus top sheeting Note sheet laminations nose Excess bottom sheeting trimmed off point construction technique ensures perfect centerline alignment tail Both Mk Mk II fuselages built same manner November 1990 85 sides top place Drawing centerline bottom sheet ing allows precise positioning rud der post After top longerons side crosspieces have glued fin ished sides fitted top bottom sheeting against bottom longerons Erect main cabin bulkheads before bend ing sides inward aft rear cabin sta tion Second lengths sheet balsa dimen sions given plan laminated graduate inward nose ring avoids awkward bending sides area forward cabin nose rough shaped sanding board progressing coarse medium paper Note different airfoil options re quire different fuselage top rails proper seating semisymmetrical section matching saddle necessitates deeper top rail allow required cutout Likewise choice nose wing op tions influences selection hold-down method consequently number location tapped hold-down blocks dow els etc Tail surfaces selection tail type de termines shape saddle bottom-mounted stabilizer MK built-up stab has cross section basically like two triangles set base base spar position Dress cross section precise contour sanding board sloping edges match shal low triangular shapes beveling edges flat spars Hold sanding Bill Evans showing off trademarks small external aileron servos Bill Winter impressed simplicity now has several models board steadily against edge spar youre working Finish moving board about gradually taking down mate rial along span rather anchoring spot Bolt-on stab mounting recommended easy transportation compact car either tail option epoxied place cer tain remove covering wood-towood joints includes covering laps around bottom saddle assembling vertical surfaces caution trial fit rudder tiller arm allowing sufficient space swing freely prevent metal-to-metal contacts thin neoprene tubing forced over tiller passed through rudder-mounted sheet metal bracket ac cepts tiller align independent finone isnt integral stabclamp thin straightedge hard straight flat piece wood cabin top aligned center marks Bend straightedge wood strip down centerline hole made tiller arm Draw guideline re move strip Evans cut MK II stab light weight foam two tapered halves butt joined centerline after being skinned A6 sheet balsa used own twosided Core Film tape attach skinning Its easy apply works well doesnt lift balsa skin Evans also used own X-Hingeslong sewn hinge strips cut length ironed close hinge gap accept MonoKote well Note leading edge spar glued foam slabs Use yellow glue similar adhesive Sand edges matching contour first achieving flat sloped surface sheeting will glued later rounding off full leading edge Evans glued stab place pre fer bolt yours sure reinforce bolt holes between top bottom sheet ing adequate quantity balsa stalled grain runs vertically Bolts will crush unsupported foam must done prior skinning Adhesives view differences ma terials between two Krackerjac ver sions few notes order wide variety glues can used balsato-balsa joints both authors used Hot Stuff instant well slow-setting because shortens building time Winter finds 3M spray-can contact cement suitable lami nating nose block sheets Epoxy used firewalls wing joiners though Win ter used white glue joiners openframe wing Both Evans Winter used two-sided Core Film skinning Contact cement may substituted make sure its com patible foam 3M spray can vari ety helps job go quickly White glue used attach balsa edge pieces foam cores Winter pro tects inside surfaces nose cavity 86 Model Aviation Above Bill Evans making slow flyby Mk ii Krackerjac crystal-clear air Bishop CA high-performance version equipped OS 60 two-stroke has ailerons rigged fiapperons Look closely youll notice flaps partially deployed Below closer look Mk ii fiapperons clearly visible model has balsaskinned foam core wing stabilizer no spoilers Winter %-1A French-curve airfoil two coats thinned epoxy Landing gear Any standard metal gear satisfactory Halico gear appropri ate size 7A-lb plane bit flimsy anything good landing original Great Planes gear wider tougher Both legs gear bent slight toe-in angle Toe-in eliminates erratic takeoff runs thereby reducing corrections Planes pronounced torque swings will behave bet ter perfectly toe-in No two degrees both toe-in castor recommended standard gear can twisted angle large bench vise Attach gear either two A-in ny lon bolts fitted blind nuts four self-tapping screws nylon bolts will shear semicrash landing broken rem nants can removed heating tip screwdriver Klett plastic gear appeared af ter design produced medium size recommended MK wing open-frame wing can built spoilers men tioned Construction techniques will fa miliar builder experience undertake project nature long Phillips entry airfoil curve leading edge near spar position bottom has characteristics close semisymmetrical section flat portion aft spars makes easy assemble bench Though spacing blocks eliminated its advisable block up leading edge ensure align ment Use standard glue epoxy tach joiners spoilers used note spar webs area front spars clear spoiler horn plans show sizes align ment bellcranks linkage spoiler servo have different servo arm travel indicated plan compensate appropriate holes dont change horn spacing spoiler Washout MK wing achieved bottom-sanding board tip area indicated plan MK II wing Evans built wing foam skinned A6 balsa sheeting airfoil approximate A-2A semisymmetrical section set less incidence MK wing produces less angular difference between wing stab improves aer obatics higher speeds Again Core Film tape X-Hinges used Other hinges may substi tuted made Robart example strong easy usesimply bore holes insert hinges epoxy Since ailerons rather thick fash ion lightest possible balsa Construction differs somewhat used foam stab leading edge built two pieces inner pieces glued flat edge foam sanded before skinning aileron spar re ceives same treatment skinning ex tends over edges After skinning leading edge proper glued front wing Its depth equal inner lead ing edge plus thickness top bottom skins Evans joiner though built A-in ply shallower shown Since UPS performed ultimate stress test changed full-depth joiner shown cut depth foam wing /6 ply slot full-depth joiner easier cut saw tapered por tion joiner will leave gap slot close-up shot Mk Iis tail feathers shows short externai cievis rod runs devises middle hoies arge horns boit visible behind rud der horn retains tail wheei tiiler arm plans show bolt-on arrangement stabilizer its epoxied place plane can filled epoxied scrap foam microballoons mixed epoxy installing two outboard servos wing bottom Evans threaded servo leads through short paper tube buried foam wing before skinning An optional standard single-servo installa tion shown requires servo cavity wood mounting pieces built after skinning panel joining completed November 1990 87 Bill Winter didnt have force smile photo just completed tower ing perfectly round loop half throttle holding gentle stick pressure corrections first flight Evans high-performance Mk ii business end Evans Mk Ii Its OS 60 swinging 11 x 7 Zinger prop simple open-nose configuration shown option plans profile less deep Winters Mk version windshield carved block balsa Vertical-grain blocks un der two wing hold-down bolts prevent crushing foam wing skin Note ex haust diverter made copper plumbing elbow retained common hose clamp Block up panel turn proper dihedral aligning wing root edge workbench sanding board can used smooth matching root sections Some foam removed ac commodate smaller front rear join ers Trial fit panels joiners until fit perfect Before permanently inserting joiners work epoxy evenly slots smooth evenly over joiners Cover center joints M-oz glass cloth Attach cloth epoxy rubbing out excess outer edges wiping off residue wing tips sloped sanding board Make plywood jig piece check ing proper angle tips made soft sheeting overlap top bottom skin leave excess Block sand match wing top bottom Covering Though iron-on coverings easy use recommend textured mate rial MK companies sell dif ferent varieties often can painted MK used silk/rayon applied buty rate fuselage finished two coats K&B epoxy paint wings tail however covered Super Mono Kote Though excellent popular prod uct turned out unsuitable large-area open-frame wing ship size weight landing made considerable vertical impact during spoiler experiments MK dead weight wings flexed down structural damage split covering chordwise edge edge Covering sheeted fuselage A-oz glass cloth attached K&B satin brush ing epoxy provides strength good finish imperviousness raw fuel glass cloth brushes out flat pulling follows curves corners After allow ing stand overnight can sanded beautifully fine-grade paper given second coat K&B epoxy col ored paint wont leave trace brush mark single coat works well two sufficient Other material re quired open stab wing Super MonoKote worked well MK II its wing being solid rather openframe construction Evans loves effect orange accented dark blue striping MK has red fuselage orange wings stab silver vertical red-orange combination happenstance Winter 25-ft roll orange hand Yellow would make less fiery contrast red background Flying Anyone building mod els already knows flyor should notes follow intended famil iarize handling characteristics Winters Evans modelsa preflight handoff speak primary focus MK Since MK intended fly wing power spectacular vertical maneuvers high-rate rolls expected craft wasnt designed per form knife-edge categoryresponses realistic stick pressures pilot MK delivers some nice performance indeed Pilots full-size air planes will sense familiar feedback fact flying model rather like being cockpit aircraft does would expect Because flies wing Mark will surprise certain modes course vertical performance would improve 60 engine much power would disadvantage other re spects bigger engine would have throttled back considerably time using high power climb ma neuvers full power heavy down trim would required due lift available would need either fly backstick remove considerable down trim dur ing approaches landings K&B 40 MK lifts off one-third power out pilots touching elevator theres no need two-thirds throttle point Incidentally 10 x 6 pro peller usual choice 11 x 5 wood prop better matched models aero batics proper center-of-gravity CG loca tion flat-bottomed airfoil section 25% chord Though pilots ac customed trimming 33% requires down trim cruising heavier control deflections inverted outside loops forward position gives solid feeling better penetration less bouncing around wind light wing load ings ride bumpily wind Approaches positive groove good test appropriateness CG location aerobatics perform outside loop constant elevator power ship buttonhooksthat tightens up during last quarter maneuver straightens back level flight lower its original altitudethis means its too nose-heavy Because model both short-coupled tail-dragger full up elevator recom mended slow taxiing grassespe cially grass long ragged begin takeoff advance throttle slowly smoothlynever abruptlywhile continu ing hold up elevator short distance typically 10 ft Actually lower power Continued page 196 88 Model Aviation Bill Evans baisa4kinned foam-core Mk ii wings root left has yet slotted joiner pians shows fuii-depth joiner requiring presiotting foam Evens inserts deep joiner through bottom slot including bottom skin cutout wing tip right msde soft sheet balsa cut oversize sanded flush top bottom sheeting foam-core stabilizer halves Evans Mk ii have skinned balsa sheeting ready joined center epoxy tips made sheet balsa --- * fl5 E Main Northvlfle Ml 481 67 Special Fast Turnaround Now Available CALL Frequency Conversion $4000 Includes Crystals Certification Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royai Tower HobbiesWorld Engines Spectrum Ana lyzers Cali brated Test struments Large Inventory R/C Parts Crystals Self I Addressed Envelope Ill Fly What Fix LeI ZAP UNIVERSITY COLLEGE OF GLUE KNOWLEDGE turn use small medical syringe meter fuel engine Cardinal will fly out sight full tank measuring fuel important Limit first test flights short engine runs five seconds stretching long practical ie long care run af ter model once things look safe Normally start priming engine hooking up battery Once prime fuel left tank run out feed measured amount check wind direc tion start engine needle valve preset produce slow run once its running its time launch its gusty day Cardinal probably ready its trim dihedral model will handle fair amount wind Make sure shes launched directly wind just slightly off right Sport flying should always much fun Krackerjac/Wi nter-Evans Continued page 90 used begin roll followed smooth steady advancing throt tle pilot wont need bold up take off allowing roll develop bit before going higher power increase airspeed point rudder has good bite steering tail-dragger steering control low speeds derives tail wheel much rud der quick surge power allowed lift tail instantly airplane will lose steering power due loss tail wheel trac tion 5-mph headwind MK will climb quickly landing pattern height one-third power power expect airplane climb rapidly fly wing two degrees dihedral permits free flight hands-off stability yielding continu ous turns either aileron rudder out compromising wingovers etc stooging around wide turns can tight ened much desired touch up el evator nose wont drop return neutral roll out plane will nose-up invert MK raise nose slightly say 100 half roll al lows time feel matching down el evator before nose drops Powered 40 engine model will sustain invert ed maneuversincluding steering figure eights etcat two-thirds power one-half going down no two-thirds go ing down circumstances Three consecutive concentric outside loops can done flying off top half power one-third one-half go ing down power speed opens up outside increasing loadings up side possibly causing twisting out ship has area thats intended used Landing approaches long airUPS US Mail Federal Express OOD Mastercard Visa Acce ted YOU WONT GET STUNG ON OUR NEW STINGER ARF Fuselage Length 525 Wing Span 84 Rec Engine Size 12 42 cu inArea 1596 sq Flying Weight 14 lbs & upRadio Channels 4 Available favorite Hobby Dealer Replacement parts available Dealer distributor inquiries invited Write today information LANIER RC PO Box 458 ood GA 30566 532-6401 Made U S 196 Model Aviation LISTED FORACOMPLETh PLEASE SEND STAMPED SELF-AL mSAATL FOR YOUR BUSINESS _____I~\I plane shows surprising ability keep coming makes really good idle essen tial bigger lower pitched prop provides bit braking Because clean ap proach use stick pressure rather movements up elevator begin flareotherwise youll go out other side Slowly build up sink touchdown gradually increasing up pressure As mentioned ship soars easily has soared out turn cross wind adding power simply trim ming rudder flat wide circles Nor mally soaring MK done climb ing moderate glide altitude going notch above idle trimming rud der continuous flat circles lift cir cle tightens speed increases go idle shut off model becomes Glid er Dress circle diameters rudder trim locked model will bank steeply go automatic Its easy see spoilers added MK though theyre optional small front-hinged spoilers typi cal blade types designed put Sail plane ground will kill some lift minimum buildup drag MK spoilers set full-open posi tion 60% vertical effect requires steady compensation up elevator goaround aborted landing possible spoilers less full power Use proportional channel radio spoilers can opened degree de sired spoiler system designed produce dethermalized descent Free Flight style thats variable slight limited full Compensating up elevator varies amount spoiler applied model can hold increasing nose-up attitude augment sink desired point STOL descent chooses Its possible fully open spoilers land ing pattern power downwind arriv ing 50 ft high just 100 ft short runway go idle STOL down head runwayor exit thermals approach 600 flight path high altitude anywhere easily hit spot spoiler action limited enough allow final flare safety tech niques fully described Winters arti cle Spoilers Power Febru ary 1986 Model Aviation flying habits MK II dont re quire special description can build youll know what MK II excels close-in maneuvers allowing nervous pilot enough reaction time prevent ships getting ahead him Due airfoil type angular rig ging spoilers appropriate gentlest headwind either model will fly ground cushion extremely low power pilot holds up elevator Winter claims has walked quickly beside MK pilot slows up too much final close ground both ships can stagger around like drunken sail ors until aileron response lost common VEND MOUNTSOn. THE VIBRATION KILLERRubber ft Engine Power Free Flight Display Fail fuel poot In. axes jaolaton 25 00 engine..eo .Control Line Electric Power RIC Airplanes File aCtually tiloWalt angIna'"Our new illustrated 32 page tabloid size catalog mounts Typical oibationtduction TOT, tae85%Tt 01 OOneieteOfUS ft Canada *100 Foreigli $300 moultIS salute four POints 0002ndt'l nn Valley Hobby center washers tubing inStruCtIOnS Sand Sf200 Otrena non Order837-A W Main St Lanadale PA 19448 000 kit GSA PRODUCTS PC 800 3602$ SARASOTA FL 34233 StOOar 3684770 3774252 FL residnts add 72% SaleS faa IRFO5MATIOR sand SASS THE KOMBAT 40 - GREAT R/C SPORT AFPLANE AND WITH SO LITTLE TIME AND MONEY INVESTED YOU CAN REALLY HAVE BALL iTS FULLY AEROBATIC AND EXTREPRELY DURABLE CONSTRUCTED OF ALUtvtIUM AND RUBBERIZED PLASTIC YOU PROVDE THE RADIO AND ENGINE WE SUPPLY EVERYTHING ELSE NO EXTRAS TO BUY 25 ENGINE MAKES GREAT ADVANCED TRAINER SPECIAL INTRODUCTORY OFFER 5 POSTPAID LIST $8995 1880 PINEVIEW MANDEVILLE LA 70448 November 1990 197 620 CRANDALL-LANESVILLE RD CORYDON INDIANA 471 LARGE SELECTION OF REMOTE CONTROL MODEL AIRPLANES AND ACCESSORIES FOR THE PROFESSIONAL A-J US TO JIG AMBROID ARCO RUBBER BANDS BRIDI DA VEYS SYSTEMS CHAMPION CO yE RITE DEVCON SIG SONIC-TRONICS STERLING SULLIVAN TOP FLITE YS ENGINES ZINGER PROPS FK art fiberglass fuSel MADE IN USA PHONE ORDERS 504 626-7840 1-8002647840 SATISFACTION GUARANTEED FLYABLE IN ONE HOUR 1EdiTT FOR ORDERS ONLYJLr7TY 1 -8OO633-7556CODs IN ALABAMA 3473525 COLLECTWELCOME TOP QUALITY FUEL FOR EXPERT OR BEGINNER NO RE-CLAIMED ALCOHOL O METHANE ONLY IS USED Designed tested give top performance both 2 cycle 4-cycle engines ringed Except engines requiring low lubricant content CONTAINS NEW TRULY SPACE AGE ADDITIVE ha deve oped nan outer space vacuum new additive attaches internal metal parts ot engine will reduce nc much 80 reduces heat wear absolute minimum WE HAVE 3 LUBRICANT BLENDS ALL SYNTHETIC OR SYNTHETIC BLEND CASTOR lOur castor new h gh Pu y much c eaner burning castor ALL OUR FUELS CONTAIN ANTIFOAMERS PREVENTERS WEAR ADDITIVES tuel developed priced nd v dus c ub d ect sales market dealer inquiries invited Ord gailon up Mis OK i 4 gailon cases up ALL FUEL EXCEPT 54 GALLON DRUMS SHIPPED FREIGHT PRE-PAID Oniy Coniinentsi USA fTo 3 GalI 23051jTo 63 GaiITO 127 Gal/ Up / Freight Collects 1 Gal4 Gal 24 Gat~64 Gal I28 Gait 54 Gal Drum 50/ 1095 0065057518500 12/1495. 95090085077528000 25%1995 1450 400 1350 1275 47500 50% 2695 22 50 2200 2075 78000 Manufactured MACH-7 PO Box 1201 Enterprise Alabama 36330 condition can landed rud-touch down withtn foot white dot der reassuring know rudder willMiracle Landing/Jollythe runway camera zooming hold heading goof go-roundContinued page 104 tight realism youre sort modeler must Mile Square wasnt closed way have fireworks build standard Stik alibbed walked away epoxyssince flying off adjacent runway piped 60 its realistic enjoyment thatnot holding up Once lower stan-under tightly controlled conditions Sport want either Krackerjacs isdards Krylon model will last for-flying continued active runway pleasant own flyeverthere no lack interested helpers paradox proved true theEach 12 flights last day Epilogue Evans shipped MK IIday 737 made see dif-picture perfect Kent would light fires Winter stab detached itficult shots wed asked like fly-and plane would accelerate lift off taped note Leave off fliesing over edge runway three feetfly Steve Korney tracked 737 over better Winters comment Ifabove ground came off hitch80 mph gear-down over 90 mph gearEvans isnt spoofing would have used ai-Imagine foam glass Krylonup literally stopped traffic nearby lerons elevons reflexed upwardscooting along 80-mph-plus over thestreets drivers spotted what appeared ral control CG atsame ground track time after time Thenbe stricken airliner landing Mile Square 20% Enough alreadythere landings model Continued page 200 PRODUCTS Complete Line Exhaust Systems Tuned Muffled Tuned Pipes Headers uri Mufflers Expansion Mufflers copter Ball Mufflers ialized Exhaust Systems Unsupassed Workmanshin B Paiformance 198 Model Aviation TulnkflvCosnWed Shotioq 1/4 Scale Kits $12995 Epoxy/Glass/Foam Construction Drawings Data Formula 120 Pylon Sport Standoff ScaleKit Price ping Credit Cards WelcomedOhio Residents Add 7%
Edition: Model Aviation - 1990/11
Page Numbers: 83, 84, 85, 86, 87, 88, 196, 197, 198
Krackerjac Mk Mk II favorite oddcouple design team backthis time two-for-one like options build RC sport plane/ trainer combo Mark soars delightfully its higher performance sibling gets excellent marks hot-dogging U Bill Winter Bill Evans VOICE OFFSTAGE go again opposite schools design coau thors have managed second last presumes unlikely collaboration West Coaster Evans loves straight-up 140 0-plus flybys known philoso phy horizontal tails tantamount buggy-whip technology East Coaster pre historic old-timer Bill Winter go-slow airplane watcher thinks straight-up folks harbor hidden rocketry complexes Still found middle ground pro duced Krackerjac MK II Asked Evans would stoop build ing conservative cabin job conspic uous stabilizer Winter would say Whats nice guy like Bill Evans doing place like two collaborated Simitar Slow Motion published January 1987 issue Model Aviation docile flying wing almost easy fly Eaglet time Winters responsiveness Simitar proj ect flabbergasted Evans Winter ever did impose certain conditions First model soarso speed range set 15 80 mph plane fully controllable either rudder aileronsso equipped elevons Because specifications fuselage behind bobtail trailing edge termination extended some eight inches rudder post Since Winter also demanded extended pe riods hands-off flying modest dihedral added Indeed Slow Motion would 720s hands-off initial tap aileron stick save weight ship Krackerjac Mark pictured before its first flight flown Bill Winter couple years before being modified installing spoilers 6-ft-span 40-powered ship has wings stabilizer open-frame construction airfoil thin flat bottomed up main spar has long Phillips entry model has over 6 sq ft area under 19-ozIsq-ft loading will soar easily weak thermals airplane takes off climbs out 1A throttle will consecutive outside loops ttle fly about verted % throttle Bill added spoilers landings could easily made short flying fields Mk Bill Winters newest version Krackerjac seen doing what Bill likes besta slow flyby low altitude low throttle Model can equipped spoilers much like Thermal Soarers help control landings lightly loaded ship Tom Schmitt photo November 1990 83 little headwind model will tly ground cushion extremely low throttle Win ter claims times has able walk quickly beside model still airborne Mk floating its wheels just above grass Tom Schmitt photo tail-dragger protect old man Evans added foot span Aerobatic capability must K&B Veco 19 maximum power after adding second foot span bringing model six feet using 05 15 power performance essentially un changed did Evans Winter join gether second time Krackerjac Winter In 1960 good systems fullhouse control around about five years us could afford single-channel escapement airplanes Lacking elevator control designs addicted ballooning turns wind fly-aways commonplace original 54-in model called K rudder-only control quick-blip high/low throttle Max 15 ended non sense plane published Air Trails kitted Jetco Incidentally throttles time used exhaust stack re strictor coupled butterfly ven turi thin airfoil long Phillips en try secret models controlla bility original handled like multi llent penetration facility per fect touch-and-goes RCs over 40-year period three continue built Antique RC Special published 1948 early-60s Krackerjac reed-systems low-wing Rookie first published Model Airplane News early Sixties later some what modified publication Model Builder Other modelers have frequently im proved upon designs continue Several years ago obtained 6-ft ver sion Krackerjac 40 power plans service built model dozen test flights magazine ex pressed desire publish major manufacturer asked about kit mag wanted perfect pictures unfortu nately Id already marred covering stall spoilers wing efficient 6 sq ft 7A lb gross weight like Glider difficult get ground 300-ft strip Krackerjac soared ease dis covered day turning cross wind leg sixth flight noted no loss altitude did 360 ended up clouds Equipped 40 model demon strated considerable prowess took off climbed one-third throttle could fly inverted respond steering half throttle performed consecutive outside loops half throttle one-third down el evator Yet magazine staff thought plane should have 120 Hard believe told kit company opinion Krackerjac wasnt mainstream hence its best interests aircraft eventually given Doug Pratt converted K&B 40 to Enya four-stroke 46 Pratt has flown three seasons happened mention Bill Evans adding could get clean photos thought should published Evans Curiosity killed cat though find horizontal tails useless appendages Winters strange short-coupled cabin its big stab bottom odd appeal could build onemy way youll seeand fly within week Winter sent print Finding untried modification using semisymmetri cal airfoil 60 power phoned him ask Which would like build said might check out never-built aerobatic version Winter uses lots sticks Im always hurry So simplified fuse went foam balsa-skinned wing stab isnt neutrally stable prefer Winter wont give up measure hands-off control otherwise flies great Winter able join California watching pleased expressions flew per formance version treasured moments Ill never live down project has tail Everybody fly visits shop ribs unmercifully too much shipped model Winter year later Alas reports UPS stress tested wing found wanting Winter So now two airplanes different performance envelope working plan original good new pictures Evans Attempts revise original print tracer ran stone wall project sat 15 months Evans Dont ever get mixed up hair-splitting old-timers Theyll drive up wall kept asking Winter Whats problem Air Force project overruns delays would have provoked Congress hed draw wed done week Finally badgered him drawing incorporating sup plementary drawings decided show cross-options stuff crammed plans could come up least four differ ent ships Maybe should have sold National Geographic Surprise editor gave him green light two 40 x 52-in sheets proposed Winter designate original Mark call Mark II added Buddy East Coast now its own Winter Which build what ex pect Marks Design objectives MK easy piloting rather like 40-powered Senior Falcon Sig Kadet Goldberg Ea gle ability groove well maneuvers better average aerobatics enough reaction time prevent airplanes getting ahead average pi lot slow landings automatic takeoff though its tail-dragger ability ride weak general lift thermal soar Fly 84 Model Aviation close-up shot shows some details Mk built-up wing spoilers shown partially deployed control servos visible under transparent wing covering Steve Kaluf demonstrates short landing tech niques using spoilers plane will land observed attitude reserve flare can abort spoilers deployed Specs spoilers Size opening location etc shown plans tailored safe flight envelope ing techniques discussed end article low wing loading 19 ozI sq ft low drag result consistent ma chine sustains open maneuvers rela tively low power hands-off stability makes relaxed flying What about bigger engine Except improved vertical maneuvers brings added power self-defeating case 60 two-stroke limit youll find yourself doing aerobatics half power potent four-stroke such Enya 60 plenty Watch center-of-gravity such heavy engine An Enya 46 fourstroke does aerobatic maneuvers except advanced such knife-edge flight careful building can achieve gross weight seven pounds Mine turned out 7 lb spoilers two extra servos Some may come 8 lb because some always Dont load up paint Since ship can soar its lightly loaded large wing being equiv alent lower loading smaller wing has significantly higher Reynolds number long low approaches neces saryand critical small field obstacles beneath approach path may overshoot 300-ft strip model too high and/or too fast may wish consider spoiler option Spoilers allow make higher approaches land within first half strip Used front-hinge did create another fun mode flying described later MK Ls open-frame wing thin well large area heavy-handed pilot using oversized engine might overstress model example dive followed abrupt pullout overapplica tion up Evans MK H Winter specified airfoil incidence power 60 en gine version faster far Mark Its also spectacular groovy its closer being neutrally stable MK airplane still safe fly hands-off Winter said wanted two degrees dihedral own insur ance fuselage sides bottom shaped framed prepared ammbly ply gear plate place corner pieces will rounded later cross pIeces glued untrimmed bottom sheet grain running lengthwise side crosspieces trimmed exactly fit Note fishtail butt loint side sheeting above stabilizer saddle docile aircraft rather different fast neutrally stable machines Im used Still found nice fly wrung out Winter California handed controls over him Its measure planes easy handling low-speed abilities cruising about half throttle Winter held light back-pressure steadily ex ecuting towering perfectly round beauti ful loopall touching controls including throttle downside model seemed rails Throughout flight OS 60 gave him power wanted Very slight back trim slower stooging around resulted prolonged slight climb 2A-/3 airfoil ship will climb one-third throttle 60 foam wing balsa skin weighs ex actly same Winters open-frame MK wingfor total model weight 7 lb model robust enough kind flying wing thicker thing increased performance MK H can flown safely anyone aileron experience Like MK will fly ruddernice know since very slow approach rudder last control fail normal aircraft As shown used two exterior-mounted small Futaba servos ailerons Ive used arrangement de signs because its simple speeds up building Winter shocked first saw quickly agreed good way go now has same setup low-wing Desperado Simitar deriva tive anhedral wing reports no trace exhaust dirt servos Winter plans details op tions shown consider before making final decision MK presented basically com plete optional spoilers shown Though spoilers bring interesting dimen sion flying theyre required Cross sections outlines shown MK II wing tail Two versions wing shown Mine slightly modi fied two-bolt-and-dowel attachment Evans wing has four bolts panel can seen Evans external bottommounted servos linkage mod ified panel shows optional standard sin gle-servo arrangement Two profiles show mounting saddle semisymmetri cal wing near side view shows Evans reshaped cabin top four-bolt attachment other shows wing modified dowel two bolts Also shown Evans simpler open nose can substituted com plicated semi-enclosed nose MK Construction Fuselage Two techniques used ease assembly First bottom lies flat workbench Evans used length A-in soft sheeting grain running length wise bottom glued A-in-sq bottom longerons crosspiec es sheeting isnt trimmed off until Left Using front cabin bulkhead ass hg builder glues sides bottom sheeting against bottom side pieces Right assembled fuselage minus top sheeting Note sheet laminations nose Excess bottom sheeting trimmed off point construction technique ensures perfect centerline alignment tail Both Mk Mk II fuselages built same manner November 1990 85 sides top place Drawing centerline bottom sheet ing allows precise positioning rud der post After top longerons side crosspieces have glued fin ished sides fitted top bottom sheeting against bottom longerons Erect main cabin bulkheads before bend ing sides inward aft rear cabin sta tion Second lengths sheet balsa dimen sions given plan laminated graduate inward nose ring avoids awkward bending sides area forward cabin nose rough shaped sanding board progressing coarse medium paper Note different airfoil options re quire different fuselage top rails proper seating semisymmetrical section matching saddle necessitates deeper top rail allow required cutout Likewise choice nose wing op tions influences selection hold-down method consequently number location tapped hold-down blocks dow els etc Tail surfaces selection tail type de termines shape saddle bottom-mounted stabilizer MK built-up stab has cross section basically like two triangles set base base spar position Dress cross section precise contour sanding board sloping edges match shal low triangular shapes beveling edges flat spars Hold sanding Bill Evans showing off trademarks small external aileron servos Bill Winter impressed simplicity now has several models board steadily against edge spar youre working Finish moving board about gradually taking down mate rial along span rather anchoring spot Bolt-on stab mounting recommended easy transportation compact car either tail option epoxied place cer tain remove covering wood-towood joints includes covering laps around bottom saddle assembling vertical surfaces caution trial fit rudder tiller arm allowing sufficient space swing freely prevent metal-to-metal contacts thin neoprene tubing forced over tiller passed through rudder-mounted sheet metal bracket ac cepts tiller align independent finone isnt integral stabclamp thin straightedge hard straight flat piece wood cabin top aligned center marks Bend straightedge wood strip down centerline hole made tiller arm Draw guideline re move strip Evans cut MK II stab light weight foam two tapered halves butt joined centerline after being skinned A6 sheet balsa used own twosided Core Film tape attach skinning Its easy apply works well doesnt lift balsa skin Evans also used own X-Hingeslong sewn hinge strips cut length ironed close hinge gap accept MonoKote well Note leading edge spar glued foam slabs Use yellow glue similar adhesive Sand edges matching contour first achieving flat sloped surface sheeting will glued later rounding off full leading edge Evans glued stab place pre fer bolt yours sure reinforce bolt holes between top bottom sheet ing adequate quantity balsa stalled grain runs vertically Bolts will crush unsupported foam must done prior skinning Adhesives view differences ma terials between two Krackerjac ver sions few notes order wide variety glues can used balsato-balsa joints both authors used Hot Stuff instant well slow-setting because shortens building time Winter finds 3M spray-can contact cement suitable lami nating nose block sheets Epoxy used firewalls wing joiners though Win ter used white glue joiners openframe wing Both Evans Winter used two-sided Core Film skinning Contact cement may substituted make sure its com patible foam 3M spray can vari ety helps job go quickly White glue used attach balsa edge pieces foam cores Winter pro tects inside surfaces nose cavity 86 Model Aviation Above Bill Evans making slow flyby Mk ii Krackerjac crystal-clear air Bishop CA high-performance version equipped OS 60 two-stroke has ailerons rigged fiapperons Look closely youll notice flaps partially deployed Below closer look Mk ii fiapperons clearly visible model has balsaskinned foam core wing stabilizer no spoilers Winter %-1A French-curve airfoil two coats thinned epoxy Landing gear Any standard metal gear satisfactory Halico gear appropri ate size 7A-lb plane bit flimsy anything good landing original Great Planes gear wider tougher Both legs gear bent slight toe-in angle Toe-in eliminates erratic takeoff runs thereby reducing corrections Planes pronounced torque swings will behave bet ter perfectly toe-in No two degrees both toe-in castor recommended standard gear can twisted angle large bench vise Attach gear either two A-in ny lon bolts fitted blind nuts four self-tapping screws nylon bolts will shear semicrash landing broken rem nants can removed heating tip screwdriver Klett plastic gear appeared af ter design produced medium size recommended MK wing open-frame wing can built spoilers men tioned Construction techniques will fa miliar builder experience undertake project nature long Phillips entry airfoil curve leading edge near spar position bottom has characteristics close semisymmetrical section flat portion aft spars makes easy assemble bench Though spacing blocks eliminated its advisable block up leading edge ensure align ment Use standard glue epoxy tach joiners spoilers used note spar webs area front spars clear spoiler horn plans show sizes align ment bellcranks linkage spoiler servo have different servo arm travel indicated plan compensate appropriate holes dont change horn spacing spoiler Washout MK wing achieved bottom-sanding board tip area indicated plan MK II wing Evans built wing foam skinned A6 balsa sheeting airfoil approximate A-2A semisymmetrical section set less incidence MK wing produces less angular difference between wing stab improves aer obatics higher speeds Again Core Film tape X-Hinges used Other hinges may substi tuted made Robart example strong easy usesimply bore holes insert hinges epoxy Since ailerons rather thick fash ion lightest possible balsa Construction differs somewhat used foam stab leading edge built two pieces inner pieces glued flat edge foam sanded before skinning aileron spar re ceives same treatment skinning ex tends over edges After skinning leading edge proper glued front wing Its depth equal inner lead ing edge plus thickness top bottom skins Evans joiner though built A-in ply shallower shown Since UPS performed ultimate stress test changed full-depth joiner shown cut depth foam wing /6 ply slot full-depth joiner easier cut saw tapered por tion joiner will leave gap slot close-up shot Mk Iis tail feathers shows short externai cievis rod runs devises middle hoies arge horns boit visible behind rud der horn retains tail wheei tiiler arm plans show bolt-on arrangement stabilizer its epoxied place plane can filled epoxied scrap foam microballoons mixed epoxy installing two outboard servos wing bottom Evans threaded servo leads through short paper tube buried foam wing before skinning An optional standard single-servo installa tion shown requires servo cavity wood mounting pieces built after skinning panel joining completed November 1990 87 Bill Winter didnt have force smile photo just completed tower ing perfectly round loop half throttle holding gentle stick pressure corrections first flight Evans high-performance Mk ii business end Evans Mk Ii Its OS 60 swinging 11 x 7 Zinger prop simple open-nose configuration shown option plans profile less deep Winters Mk version windshield carved block balsa Vertical-grain blocks un der two wing hold-down bolts prevent crushing foam wing skin Note ex haust diverter made copper plumbing elbow retained common hose clamp Block up panel turn proper dihedral aligning wing root edge workbench sanding board can used smooth matching root sections Some foam removed ac commodate smaller front rear join ers Trial fit panels joiners until fit perfect Before permanently inserting joiners work epoxy evenly slots smooth evenly over joiners Cover center joints M-oz glass cloth Attach cloth epoxy rubbing out excess outer edges wiping off residue wing tips sloped sanding board Make plywood jig piece check ing proper angle tips made soft sheeting overlap top bottom skin leave excess Block sand match wing top bottom Covering Though iron-on coverings easy use recommend textured mate rial MK companies sell dif ferent varieties often can painted MK used silk/rayon applied buty rate fuselage finished two coats K&B epoxy paint wings tail however covered Super Mono Kote Though excellent popular prod uct turned out unsuitable large-area open-frame wing ship size weight landing made considerable vertical impact during spoiler experiments MK dead weight wings flexed down structural damage split covering chordwise edge edge Covering sheeted fuselage A-oz glass cloth attached K&B satin brush ing epoxy provides strength good finish imperviousness raw fuel glass cloth brushes out flat pulling follows curves corners After allow ing stand overnight can sanded beautifully fine-grade paper given second coat K&B epoxy col ored paint wont leave trace brush mark single coat works well two sufficient Other material re quired open stab wing Super MonoKote worked well MK II its wing being solid rather openframe construction Evans loves effect orange accented dark blue striping MK has red fuselage orange wings stab silver vertical red-orange combination happenstance Winter 25-ft roll orange hand Yellow would make less fiery contrast red background Flying Anyone building mod els already knows flyor should notes follow intended famil iarize handling characteristics Winters Evans modelsa preflight handoff speak primary focus MK Since MK intended fly wing power spectacular vertical maneuvers high-rate rolls expected craft wasnt designed per form knife-edge categoryresponses realistic stick pressures pilot MK delivers some nice performance indeed Pilots full-size air planes will sense familiar feedback fact flying model rather like being cockpit aircraft does would expect Because flies wing Mark will surprise certain modes course vertical performance would improve 60 engine much power would disadvantage other re spects bigger engine would have throttled back considerably time using high power climb ma neuvers full power heavy down trim would required due lift available would need either fly backstick remove considerable down trim dur ing approaches landings K&B 40 MK lifts off one-third power out pilots touching elevator theres no need two-thirds throttle point Incidentally 10 x 6 pro peller usual choice 11 x 5 wood prop better matched models aero batics proper center-of-gravity CG loca tion flat-bottomed airfoil section 25% chord Though pilots ac customed trimming 33% requires down trim cruising heavier control deflections inverted outside loops forward position gives solid feeling better penetration less bouncing around wind light wing load ings ride bumpily wind Approaches positive groove good test appropriateness CG location aerobatics perform outside loop constant elevator power ship buttonhooksthat tightens up during last quarter maneuver straightens back level flight lower its original altitudethis means its too nose-heavy Because model both short-coupled tail-dragger full up elevator recom mended slow taxiing grassespe cially grass long ragged begin takeoff advance throttle slowly smoothlynever abruptlywhile continu ing hold up elevator short distance typically 10 ft Actually lower power Continued page 196 88 Model Aviation Bill Evans baisa4kinned foam-core Mk ii wings root left has yet slotted joiner pians shows fuii-depth joiner requiring presiotting foam Evens inserts deep joiner through bottom slot including bottom skin cutout wing tip right msde soft sheet balsa cut oversize sanded flush top bottom sheeting foam-core stabilizer halves Evans Mk ii have skinned balsa sheeting ready joined center epoxy tips made sheet balsa --- * fl5 E Main Northvlfle Ml 481 67 Special Fast Turnaround Now Available CALL Frequency Conversion $4000 Includes Crystals Certification Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royai Tower HobbiesWorld Engines Spectrum Ana lyzers Cali brated Test struments Large Inventory R/C Parts Crystals Self I Addressed Envelope Ill Fly What Fix LeI ZAP UNIVERSITY COLLEGE OF GLUE KNOWLEDGE turn use small medical syringe meter fuel engine Cardinal will fly out sight full tank measuring fuel important Limit first test flights short engine runs five seconds stretching long practical ie long care run af ter model once things look safe Normally start priming engine hooking up battery Once prime fuel left tank run out feed measured amount check wind direc tion start engine needle valve preset produce slow run once its running its time launch its gusty day Cardinal probably ready its trim dihedral model will handle fair amount wind Make sure shes launched directly wind just slightly off right Sport flying should always much fun Krackerjac/Wi nter-Evans Continued page 90 used begin roll followed smooth steady advancing throt tle pilot wont need bold up take off allowing roll develop bit before going higher power increase airspeed point rudder has good bite steering tail-dragger steering control low speeds derives tail wheel much rud der quick surge power allowed lift tail instantly airplane will lose steering power due loss tail wheel trac tion 5-mph headwind MK will climb quickly landing pattern height one-third power power expect airplane climb rapidly fly wing two degrees dihedral permits free flight hands-off stability yielding continu ous turns either aileron rudder out compromising wingovers etc stooging around wide turns can tight ened much desired touch up el evator nose wont drop return neutral roll out plane will nose-up invert MK raise nose slightly say 100 half roll al lows time feel matching down el evator before nose drops Powered 40 engine model will sustain invert ed maneuversincluding steering figure eights etcat two-thirds power one-half going down no two-thirds go ing down circumstances Three consecutive concentric outside loops can done flying off top half power one-third one-half go ing down power speed opens up outside increasing loadings up side possibly causing twisting out ship has area thats intended used Landing approaches long airUPS US Mail Federal Express OOD Mastercard Visa Acce ted YOU WONT GET STUNG ON OUR NEW STINGER ARF Fuselage Length 525 Wing Span 84 Rec Engine Size 12 42 cu inArea 1596 sq Flying Weight 14 lbs & upRadio Channels 4 Available favorite Hobby Dealer Replacement parts available Dealer distributor inquiries invited Write today information LANIER RC PO Box 458 ood GA 30566 532-6401 Made U S 196 Model Aviation LISTED FORACOMPLETh PLEASE SEND STAMPED SELF-AL mSAATL FOR YOUR BUSINESS _____I~\I plane shows surprising ability keep coming makes really good idle essen tial bigger lower pitched prop provides bit braking Because clean ap proach use stick pressure rather movements up elevator begin flareotherwise youll go out other side Slowly build up sink touchdown gradually increasing up pressure As mentioned ship soars easily has soared out turn cross wind adding power simply trim ming rudder flat wide circles Nor mally soaring MK done climb ing moderate glide altitude going notch above idle trimming rud der continuous flat circles lift cir cle tightens speed increases go idle shut off model becomes Glid er Dress circle diameters rudder trim locked model will bank steeply go automatic Its easy see spoilers added MK though theyre optional small front-hinged spoilers typi cal blade types designed put Sail plane ground will kill some lift minimum buildup drag MK spoilers set full-open posi tion 60% vertical effect requires steady compensation up elevator goaround aborted landing possible spoilers less full power Use proportional channel radio spoilers can opened degree de sired spoiler system designed produce dethermalized descent Free Flight style thats variable slight limited full Compensating up elevator varies amount spoiler applied model can hold increasing nose-up attitude augment sink desired point STOL descent chooses Its possible fully open spoilers land ing pattern power downwind arriv ing 50 ft high just 100 ft short runway go idle STOL down head runwayor exit thermals approach 600 flight path high altitude anywhere easily hit spot spoiler action limited enough allow final flare safety tech niques fully described Winters arti cle Spoilers Power Febru ary 1986 Model Aviation flying habits MK II dont re quire special description can build youll know what MK II excels close-in maneuvers allowing nervous pilot enough reaction time prevent ships getting ahead him Due airfoil type angular rig ging spoilers appropriate gentlest headwind either model will fly ground cushion extremely low power pilot holds up elevator Winter claims has walked quickly beside MK pilot slows up too much final close ground both ships can stagger around like drunken sail ors until aileron response lost common VEND MOUNTSOn. THE VIBRATION KILLERRubber ft Engine Power Free Flight Display Fail fuel poot In. axes jaolaton 25 00 engine..eo .Control Line Electric Power RIC Airplanes File aCtually tiloWalt angIna'"Our new illustrated 32 page tabloid size catalog mounts Typical oibationtduction TOT, tae85%Tt 01 OOneieteOfUS ft Canada *100 Foreigli $300 moultIS salute four POints 0002ndt'l nn Valley Hobby center washers tubing inStruCtIOnS Sand Sf200 Otrena non Order837-A W Main St Lanadale PA 19448 000 kit GSA PRODUCTS PC 800 3602$ SARASOTA FL 34233 StOOar 3684770 3774252 FL residnts add 72% SaleS faa IRFO5MATIOR sand SASS THE KOMBAT 40 - GREAT R/C SPORT AFPLANE AND WITH SO LITTLE TIME AND MONEY INVESTED YOU CAN REALLY HAVE BALL iTS FULLY AEROBATIC AND EXTREPRELY DURABLE CONSTRUCTED OF ALUtvtIUM AND RUBBERIZED PLASTIC YOU PROVDE THE RADIO AND ENGINE WE SUPPLY EVERYTHING ELSE NO EXTRAS TO BUY 25 ENGINE MAKES GREAT ADVANCED TRAINER SPECIAL INTRODUCTORY OFFER 5 POSTPAID LIST $8995 1880 PINEVIEW MANDEVILLE LA 70448 November 1990 197 620 CRANDALL-LANESVILLE RD CORYDON INDIANA 471 LARGE SELECTION OF REMOTE CONTROL MODEL AIRPLANES AND ACCESSORIES FOR THE PROFESSIONAL A-J US TO JIG AMBROID ARCO RUBBER BANDS BRIDI DA VEYS SYSTEMS CHAMPION CO yE RITE DEVCON SIG SONIC-TRONICS STERLING SULLIVAN TOP FLITE YS ENGINES ZINGER PROPS FK art fiberglass fuSel MADE IN USA PHONE ORDERS 504 626-7840 1-8002647840 SATISFACTION GUARANTEED FLYABLE IN ONE HOUR 1EdiTT FOR ORDERS ONLYJLr7TY 1 -8OO633-7556CODs IN ALABAMA 3473525 COLLECTWELCOME TOP QUALITY FUEL FOR EXPERT OR BEGINNER NO RE-CLAIMED ALCOHOL O METHANE ONLY IS USED Designed tested give top performance both 2 cycle 4-cycle engines ringed Except engines requiring low lubricant content CONTAINS NEW TRULY SPACE AGE ADDITIVE ha deve oped nan outer space vacuum new additive attaches internal metal parts ot engine will reduce nc much 80 reduces heat wear absolute minimum WE HAVE 3 LUBRICANT BLENDS ALL SYNTHETIC OR SYNTHETIC BLEND CASTOR lOur castor new h gh Pu y much c eaner burning castor ALL OUR FUELS CONTAIN ANTIFOAMERS PREVENTERS WEAR ADDITIVES tuel developed priced nd v dus c ub d ect sales market dealer inquiries invited Ord gailon up Mis OK i 4 gailon cases up ALL FUEL EXCEPT 54 GALLON DRUMS SHIPPED FREIGHT PRE-PAID Oniy Coniinentsi USA fTo 3 GalI 23051jTo 63 GaiITO 127 Gal/ Up / Freight Collects 1 Gal4 Gal 24 Gat~64 Gal I28 Gait 54 Gal Drum 50/ 1095 0065057518500 12/1495. 95090085077528000 25%1995 1450 400 1350 1275 47500 50% 2695 22 50 2200 2075 78000 Manufactured MACH-7 PO Box 1201 Enterprise Alabama 36330 condition can landed rud-touch down withtn foot white dot der reassuring know rudder willMiracle Landing/Jollythe runway camera zooming hold heading goof go-roundContinued page 104 tight realism youre sort modeler must Mile Square wasnt closed way have fireworks build standard Stik alibbed walked away epoxyssince flying off adjacent runway piped 60 its realistic enjoyment thatnot holding up Once lower stan-under tightly controlled conditions Sport want either Krackerjacs isdards Krylon model will last for-flying continued active runway pleasant own flyeverthere no lack interested helpers paradox proved true theEach 12 flights last day Epilogue Evans shipped MK IIday 737 made see dif-picture perfect Kent would light fires Winter stab detached itficult shots wed asked like fly-and plane would accelerate lift off taped note Leave off fliesing over edge runway three feetfly Steve Korney tracked 737 over better Winters comment Ifabove ground came off hitch80 mph gear-down over 90 mph gearEvans isnt spoofing would have used ai-Imagine foam glass Krylonup literally stopped traffic nearby lerons elevons reflexed upwardscooting along 80-mph-plus over thestreets drivers spotted what appeared ral control CG atsame ground track time after time Thenbe stricken airliner landing Mile Square 20% Enough alreadythere landings model Continued page 200 PRODUCTS Complete Line Exhaust Systems Tuned Muffled Tuned Pipes Headers uri Mufflers Expansion Mufflers copter Ball Mufflers ialized Exhaust Systems Unsupassed Workmanshin B Paiformance 198 Model Aviation TulnkflvCosnWed Shotioq 1/4 Scale Kits $12995 Epoxy/Glass/Foam Construction Drawings Data Formula 120 Pylon Sport Standoff ScaleKit Price ping Credit Cards WelcomedOhio Residents Add 7%
Edition: Model Aviation - 1990/11
Page Numbers: 83, 84, 85, 86, 87, 88, 196, 197, 198
Krackerjac Mk Mk II favorite oddcouple design team backthis time two-for-one like options build RC sport plane/ trainer combo Mark soars delightfully its higher performance sibling gets excellent marks hot-dogging U Bill Winter Bill Evans VOICE OFFSTAGE go again opposite schools design coau thors have managed second last presumes unlikely collaboration West Coaster Evans loves straight-up 140 0-plus flybys known philoso phy horizontal tails tantamount buggy-whip technology East Coaster pre historic old-timer Bill Winter go-slow airplane watcher thinks straight-up folks harbor hidden rocketry complexes Still found middle ground pro duced Krackerjac MK II Asked Evans would stoop build ing conservative cabin job conspic uous stabilizer Winter would say Whats nice guy like Bill Evans doing place like two collaborated Simitar Slow Motion published January 1987 issue Model Aviation docile flying wing almost easy fly Eaglet time Winters responsiveness Simitar proj ect flabbergasted Evans Winter ever did impose certain conditions First model soarso speed range set 15 80 mph plane fully controllable either rudder aileronsso equipped elevons Because specifications fuselage behind bobtail trailing edge termination extended some eight inches rudder post Since Winter also demanded extended pe riods hands-off flying modest dihedral added Indeed Slow Motion would 720s hands-off initial tap aileron stick save weight ship Krackerjac Mark pictured before its first flight flown Bill Winter couple years before being modified installing spoilers 6-ft-span 40-powered ship has wings stabilizer open-frame construction airfoil thin flat bottomed up main spar has long Phillips entry model has over 6 sq ft area under 19-ozIsq-ft loading will soar easily weak thermals airplane takes off climbs out 1A throttle will consecutive outside loops ttle fly about verted % throttle Bill added spoilers landings could easily made short flying fields Mk Bill Winters newest version Krackerjac seen doing what Bill likes besta slow flyby low altitude low throttle Model can equipped spoilers much like Thermal Soarers help control landings lightly loaded ship Tom Schmitt photo November 1990 83 little headwind model will tly ground cushion extremely low throttle Win ter claims times has able walk quickly beside model still airborne Mk floating its wheels just above grass Tom Schmitt photo tail-dragger protect old man Evans added foot span Aerobatic capability must K&B Veco 19 maximum power after adding second foot span bringing model six feet using 05 15 power performance essentially un changed did Evans Winter join gether second time Krackerjac Winter In 1960 good systems fullhouse control around about five years us could afford single-channel escapement airplanes Lacking elevator control designs addicted ballooning turns wind fly-aways commonplace original 54-in model called K rudder-only control quick-blip high/low throttle Max 15 ended non sense plane published Air Trails kitted Jetco Incidentally throttles time used exhaust stack re strictor coupled butterfly ven turi thin airfoil long Phillips en try secret models controlla bility original handled like multi llent penetration facility per fect touch-and-goes RCs over 40-year period three continue built Antique RC Special published 1948 early-60s Krackerjac reed-systems low-wing Rookie first published Model Airplane News early Sixties later some what modified publication Model Builder Other modelers have frequently im proved upon designs continue Several years ago obtained 6-ft ver sion Krackerjac 40 power plans service built model dozen test flights magazine ex pressed desire publish major manufacturer asked about kit mag wanted perfect pictures unfortu nately Id already marred covering stall spoilers wing efficient 6 sq ft 7A lb gross weight like Glider difficult get ground 300-ft strip Krackerjac soared ease dis covered day turning cross wind leg sixth flight noted no loss altitude did 360 ended up clouds Equipped 40 model demon strated considerable prowess took off climbed one-third throttle could fly inverted respond steering half throttle performed consecutive outside loops half throttle one-third down el evator Yet magazine staff thought plane should have 120 Hard believe told kit company opinion Krackerjac wasnt mainstream hence its best interests aircraft eventually given Doug Pratt converted K&B 40 to Enya four-stroke 46 Pratt has flown three seasons happened mention Bill Evans adding could get clean photos thought should published Evans Curiosity killed cat though find horizontal tails useless appendages Winters strange short-coupled cabin its big stab bottom odd appeal could build onemy way youll seeand fly within week Winter sent print Finding untried modification using semisymmetri cal airfoil 60 power phoned him ask Which would like build said might check out never-built aerobatic version Winter uses lots sticks Im always hurry So simplified fuse went foam balsa-skinned wing stab isnt neutrally stable prefer Winter wont give up measure hands-off control otherwise flies great Winter able join California watching pleased expressions flew per formance version treasured moments Ill never live down project has tail Everybody fly visits shop ribs unmercifully too much shipped model Winter year later Alas reports UPS stress tested wing found wanting Winter So now two airplanes different performance envelope working plan original good new pictures Evans Attempts revise original print tracer ran stone wall project sat 15 months Evans Dont ever get mixed up hair-splitting old-timers Theyll drive up wall kept asking Winter Whats problem Air Force project overruns delays would have provoked Congress hed draw wed done week Finally badgered him drawing incorporating sup plementary drawings decided show cross-options stuff crammed plans could come up least four differ ent ships Maybe should have sold National Geographic Surprise editor gave him green light two 40 x 52-in sheets proposed Winter designate original Mark call Mark II added Buddy East Coast now its own Winter Which build what ex pect Marks Design objectives MK easy piloting rather like 40-powered Senior Falcon Sig Kadet Goldberg Ea gle ability groove well maneuvers better average aerobatics enough reaction time prevent airplanes getting ahead average pi lot slow landings automatic takeoff though its tail-dragger ability ride weak general lift thermal soar Fly 84 Model Aviation close-up shot shows some details Mk built-up wing spoilers shown partially deployed control servos visible under transparent wing covering Steve Kaluf demonstrates short landing tech niques using spoilers plane will land observed attitude reserve flare can abort spoilers deployed Specs spoilers Size opening location etc shown plans tailored safe flight envelope ing techniques discussed end article low wing loading 19 ozI sq ft low drag result consistent ma chine sustains open maneuvers rela tively low power hands-off stability makes relaxed flying What about bigger engine Except improved vertical maneuvers brings added power self-defeating case 60 two-stroke limit youll find yourself doing aerobatics half power potent four-stroke such Enya 60 plenty Watch center-of-gravity such heavy engine An Enya 46 fourstroke does aerobatic maneuvers except advanced such knife-edge flight careful building can achieve gross weight seven pounds Mine turned out 7 lb spoilers two extra servos Some may come 8 lb because some always Dont load up paint Since ship can soar its lightly loaded large wing being equiv alent lower loading smaller wing has significantly higher Reynolds number long low approaches neces saryand critical small field obstacles beneath approach path may overshoot 300-ft strip model too high and/or too fast may wish consider spoiler option Spoilers allow make higher approaches land within first half strip Used front-hinge did create another fun mode flying described later MK Ls open-frame wing thin well large area heavy-handed pilot using oversized engine might overstress model example dive followed abrupt pullout overapplica tion up Evans MK H Winter specified airfoil incidence power 60 en gine version faster far Mark Its also spectacular groovy its closer being neutrally stable MK airplane still safe fly hands-off Winter said wanted two degrees dihedral own insur ance fuselage sides bottom shaped framed prepared ammbly ply gear plate place corner pieces will rounded later cross pIeces glued untrimmed bottom sheet grain running lengthwise side crosspieces trimmed exactly fit Note fishtail butt loint side sheeting above stabilizer saddle docile aircraft rather different fast neutrally stable machines Im used Still found nice fly wrung out Winter California handed controls over him Its measure planes easy handling low-speed abilities cruising about half throttle Winter held light back-pressure steadily ex ecuting towering perfectly round beauti ful loopall touching controls including throttle downside model seemed rails Throughout flight OS 60 gave him power wanted Very slight back trim slower stooging around resulted prolonged slight climb 2A-/3 airfoil ship will climb one-third throttle 60 foam wing balsa skin weighs ex actly same Winters open-frame MK wingfor total model weight 7 lb model robust enough kind flying wing thicker thing increased performance MK H can flown safely anyone aileron experience Like MK will fly ruddernice know since very slow approach rudder last control fail normal aircraft As shown used two exterior-mounted small Futaba servos ailerons Ive used arrangement de signs because its simple speeds up building Winter shocked first saw quickly agreed good way go now has same setup low-wing Desperado Simitar deriva tive anhedral wing reports no trace exhaust dirt servos Winter plans details op tions shown consider before making final decision MK presented basically com plete optional spoilers shown Though spoilers bring interesting dimen sion flying theyre required Cross sections outlines shown MK II wing tail Two versions wing shown Mine slightly modi fied two-bolt-and-dowel attachment Evans wing has four bolts panel can seen Evans external bottommounted servos linkage mod ified panel shows optional standard sin gle-servo arrangement Two profiles show mounting saddle semisymmetri cal wing near side view shows Evans reshaped cabin top four-bolt attachment other shows wing modified dowel two bolts Also shown Evans simpler open nose can substituted com plicated semi-enclosed nose MK Construction Fuselage Two techniques used ease assembly First bottom lies flat workbench Evans used length A-in soft sheeting grain running length wise bottom glued A-in-sq bottom longerons crosspiec es sheeting isnt trimmed off until Left Using front cabin bulkhead ass hg builder glues sides bottom sheeting against bottom side pieces Right assembled fuselage minus top sheeting Note sheet laminations nose Excess bottom sheeting trimmed off point construction technique ensures perfect centerline alignment tail Both Mk Mk II fuselages built same manner November 1990 85 sides top place Drawing centerline bottom sheet ing allows precise positioning rud der post After top longerons side crosspieces have glued fin ished sides fitted top bottom sheeting against bottom longerons Erect main cabin bulkheads before bend ing sides inward aft rear cabin sta tion Second lengths sheet balsa dimen sions given plan laminated graduate inward nose ring avoids awkward bending sides area forward cabin nose rough shaped sanding board progressing coarse medium paper Note different airfoil options re quire different fuselage top rails proper seating semisymmetrical section matching saddle necessitates deeper top rail allow required cutout Likewise choice nose wing op tions influences selection hold-down method consequently number location tapped hold-down blocks dow els etc Tail surfaces selection tail type de termines shape saddle bottom-mounted stabilizer MK built-up stab has cross section basically like two triangles set base base spar position Dress cross section precise contour sanding board sloping edges match shal low triangular shapes beveling edges flat spars Hold sanding Bill Evans showing off trademarks small external aileron servos Bill Winter impressed simplicity now has several models board steadily against edge spar youre working Finish moving board about gradually taking down mate rial along span rather anchoring spot Bolt-on stab mounting recommended easy transportation compact car either tail option epoxied place cer tain remove covering wood-towood joints includes covering laps around bottom saddle assembling vertical surfaces caution trial fit rudder tiller arm allowing sufficient space swing freely prevent metal-to-metal contacts thin neoprene tubing forced over tiller passed through rudder-mounted sheet metal bracket ac cepts tiller align independent finone isnt integral stabclamp thin straightedge hard straight flat piece wood cabin top aligned center marks Bend straightedge wood strip down centerline hole made tiller arm Draw guideline re move strip Evans cut MK II stab light weight foam two tapered halves butt joined centerline after being skinned A6 sheet balsa used own twosided Core Film tape attach skinning Its easy apply works well doesnt lift balsa skin Evans also used own X-Hingeslong sewn hinge strips cut length ironed close hinge gap accept MonoKote well Note leading edge spar glued foam slabs Use yellow glue similar adhesive Sand edges matching contour first achieving flat sloped surface sheeting will glued later rounding off full leading edge Evans glued stab place pre fer bolt yours sure reinforce bolt holes between top bottom sheet ing adequate quantity balsa stalled grain runs vertically Bolts will crush unsupported foam must done prior skinning Adhesives view differences ma terials between two Krackerjac ver sions few notes order wide variety glues can used balsato-balsa joints both authors used Hot Stuff instant well slow-setting because shortens building time Winter finds 3M spray-can contact cement suitable lami nating nose block sheets Epoxy used firewalls wing joiners though Win ter used white glue joiners openframe wing Both Evans Winter used two-sided Core Film skinning Contact cement may substituted make sure its com patible foam 3M spray can vari ety helps job go quickly White glue used attach balsa edge pieces foam cores Winter pro tects inside surfaces nose cavity 86 Model Aviation Above Bill Evans making slow flyby Mk ii Krackerjac crystal-clear air Bishop CA high-performance version equipped OS 60 two-stroke has ailerons rigged fiapperons Look closely youll notice flaps partially deployed Below closer look Mk ii fiapperons clearly visible model has balsaskinned foam core wing stabilizer no spoilers Winter %-1A French-curve airfoil two coats thinned epoxy Landing gear Any standard metal gear satisfactory Halico gear appropri ate size 7A-lb plane bit flimsy anything good landing original Great Planes gear wider tougher Both legs gear bent slight toe-in angle Toe-in eliminates erratic takeoff runs thereby reducing corrections Planes pronounced torque swings will behave bet ter perfectly toe-in No two degrees both toe-in castor recommended standard gear can twisted angle large bench vise Attach gear either two A-in ny lon bolts fitted blind nuts four self-tapping screws nylon bolts will shear semicrash landing broken rem nants can removed heating tip screwdriver Klett plastic gear appeared af ter design produced medium size recommended MK wing open-frame wing can built spoilers men tioned Construction techniques will fa miliar builder experience undertake project nature long Phillips entry airfoil curve leading edge near spar position bottom has characteristics close semisymmetrical section flat portion aft spars makes easy assemble bench Though spacing blocks eliminated its advisable block up leading edge ensure align ment Use standard glue epoxy tach joiners spoilers used note spar webs area front spars clear spoiler horn plans show sizes align ment bellcranks linkage spoiler servo have different servo arm travel indicated plan compensate appropriate holes dont change horn spacing spoiler Washout MK wing achieved bottom-sanding board tip area indicated plan MK II wing Evans built wing foam skinned A6 balsa sheeting airfoil approximate A-2A semisymmetrical section set less incidence MK wing produces less angular difference between wing stab improves aer obatics higher speeds Again Core Film tape X-Hinges used Other hinges may substi tuted made Robart example strong easy usesimply bore holes insert hinges epoxy Since ailerons rather thick fash ion lightest possible balsa Construction differs somewhat used foam stab leading edge built two pieces inner pieces glued flat edge foam sanded before skinning aileron spar re ceives same treatment skinning ex tends over edges After skinning leading edge proper glued front wing Its depth equal inner lead ing edge plus thickness top bottom skins Evans joiner though built A-in ply shallower shown Since UPS performed ultimate stress test changed full-depth joiner shown cut depth foam wing /6 ply slot full-depth joiner easier cut saw tapered por tion joiner will leave gap slot close-up shot Mk Iis tail feathers shows short externai cievis rod runs devises middle hoies arge horns boit visible behind rud der horn retains tail wheei tiiler arm plans show bolt-on arrangement stabilizer its epoxied place plane can filled epoxied scrap foam microballoons mixed epoxy installing two outboard servos wing bottom Evans threaded servo leads through short paper tube buried foam wing before skinning An optional standard single-servo installa tion shown requires servo cavity wood mounting pieces built after skinning panel joining completed November 1990 87 Bill Winter didnt have force smile photo just completed tower ing perfectly round loop half throttle holding gentle stick pressure corrections first flight Evans high-performance Mk ii business end Evans Mk Ii Its OS 60 swinging 11 x 7 Zinger prop simple open-nose configuration shown option plans profile less deep Winters Mk version windshield carved block balsa Vertical-grain blocks un der two wing hold-down bolts prevent crushing foam wing skin Note ex haust diverter made copper plumbing elbow retained common hose clamp Block up panel turn proper dihedral aligning wing root edge workbench sanding board can used smooth matching root sections Some foam removed ac commodate smaller front rear join ers Trial fit panels joiners until fit perfect Before permanently inserting joiners work epoxy evenly slots smooth evenly over joiners Cover center joints M-oz glass cloth Attach cloth epoxy rubbing out excess outer edges wiping off residue wing tips sloped sanding board Make plywood jig piece check ing proper angle tips made soft sheeting overlap top bottom skin leave excess Block sand match wing top bottom Covering Though iron-on coverings easy use recommend textured mate rial MK companies sell dif ferent varieties often can painted MK used silk/rayon applied buty rate fuselage finished two coats K&B epoxy paint wings tail however covered Super Mono Kote Though excellent popular prod uct turned out unsuitable large-area open-frame wing ship size weight landing made considerable vertical impact during spoiler experiments MK dead weight wings flexed down structural damage split covering chordwise edge edge Covering sheeted fuselage A-oz glass cloth attached K&B satin brush ing epoxy provides strength good finish imperviousness raw fuel glass cloth brushes out flat pulling follows curves corners After allow ing stand overnight can sanded beautifully fine-grade paper given second coat K&B epoxy col ored paint wont leave trace brush mark single coat works well two sufficient Other material re quired open stab wing Super MonoKote worked well MK II its wing being solid rather openframe construction Evans loves effect orange accented dark blue striping MK has red fuselage orange wings stab silver vertical red-orange combination happenstance Winter 25-ft roll orange hand Yellow would make less fiery contrast red background Flying Anyone building mod els already knows flyor should notes follow intended famil iarize handling characteristics Winters Evans modelsa preflight handoff speak primary focus MK Since MK intended fly wing power spectacular vertical maneuvers high-rate rolls expected craft wasnt designed per form knife-edge categoryresponses realistic stick pressures pilot MK delivers some nice performance indeed Pilots full-size air planes will sense familiar feedback fact flying model rather like being cockpit aircraft does would expect Because flies wing Mark will surprise certain modes course vertical performance would improve 60 engine much power would disadvantage other re spects bigger engine would have throttled back considerably time using high power climb ma neuvers full power heavy down trim would required due lift available would need either fly backstick remove considerable down trim dur ing approaches landings K&B 40 MK lifts off one-third power out pilots touching elevator theres no need two-thirds throttle point Incidentally 10 x 6 pro peller usual choice 11 x 5 wood prop better matched models aero batics proper center-of-gravity CG loca tion flat-bottomed airfoil section 25% chord Though pilots ac customed trimming 33% requires down trim cruising heavier control deflections inverted outside loops forward position gives solid feeling better penetration less bouncing around wind light wing load ings ride bumpily wind Approaches positive groove good test appropriateness CG location aerobatics perform outside loop constant elevator power ship buttonhooksthat tightens up during last quarter maneuver straightens back level flight lower its original altitudethis means its too nose-heavy Because model both short-coupled tail-dragger full up elevator recom mended slow taxiing grassespe cially grass long ragged begin takeoff advance throttle slowly smoothlynever abruptlywhile continu ing hold up elevator short distance typically 10 ft Actually lower power Continued page 196 88 Model Aviation Bill Evans baisa4kinned foam-core Mk ii wings root left has yet slotted joiner pians shows fuii-depth joiner requiring presiotting foam Evens inserts deep joiner through bottom slot including bottom skin cutout wing tip right msde soft sheet balsa cut oversize sanded flush top bottom sheeting foam-core stabilizer halves Evans Mk ii have skinned balsa sheeting ready joined center epoxy tips made sheet balsa --- * fl5 E Main Northvlfle Ml 481 67 Special Fast Turnaround Now Available CALL Frequency Conversion $4000 Includes Crystals Certification Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royai Tower HobbiesWorld Engines Spectrum Ana lyzers Cali brated Test struments Large Inventory R/C Parts Crystals Self I Addressed Envelope Ill Fly What Fix LeI ZAP UNIVERSITY COLLEGE OF GLUE KNOWLEDGE turn use small medical syringe meter fuel engine Cardinal will fly out sight full tank measuring fuel important Limit first test flights short engine runs five seconds stretching long practical ie long care run af ter model once things look safe Normally start priming engine hooking up battery Once prime fuel left tank run out feed measured amount check wind direc tion start engine needle valve preset produce slow run once its running its time launch its gusty day Cardinal probably ready its trim dihedral model will handle fair amount wind Make sure shes launched directly wind just slightly off right Sport flying should always much fun Krackerjac/Wi nter-Evans Continued page 90 used begin roll followed smooth steady advancing throt tle pilot wont need bold up take off allowing roll develop bit before going higher power increase airspeed point rudder has good bite steering tail-dragger steering control low speeds derives tail wheel much rud der quick surge power allowed lift tail instantly airplane will lose steering power due loss tail wheel trac tion 5-mph headwind MK will climb quickly landing pattern height one-third power power expect airplane climb rapidly fly wing two degrees dihedral permits free flight hands-off stability yielding continu ous turns either aileron rudder out compromising wingovers etc stooging around wide turns can tight ened much desired touch up el evator nose wont drop return neutral roll out plane will nose-up invert MK raise nose slightly say 100 half roll al lows time feel matching down el evator before nose drops Powered 40 engine model will sustain invert ed maneuversincluding steering figure eights etcat two-thirds power one-half going down no two-thirds go ing down circumstances Three consecutive concentric outside loops can done flying off top half power one-third one-half go ing down power speed opens up outside increasing loadings up side possibly causing twisting out ship has area thats intended used Landing approaches long airUPS US Mail Federal Express OOD Mastercard Visa Acce ted YOU WONT GET STUNG ON OUR NEW STINGER ARF Fuselage Length 525 Wing Span 84 Rec Engine Size 12 42 cu inArea 1596 sq Flying Weight 14 lbs & upRadio Channels 4 Available favorite Hobby Dealer Replacement parts available Dealer distributor inquiries invited Write today information LANIER RC PO Box 458 ood GA 30566 532-6401 Made U S 196 Model Aviation LISTED FORACOMPLETh PLEASE SEND STAMPED SELF-AL mSAATL FOR YOUR BUSINESS _____I~\I plane shows surprising ability keep coming makes really good idle essen tial bigger lower pitched prop provides bit braking Because clean ap proach use stick pressure rather movements up elevator begin flareotherwise youll go out other side Slowly build up sink touchdown gradually increasing up pressure As mentioned ship soars easily has soared out turn cross wind adding power simply trim ming rudder flat wide circles Nor mally soaring MK done climb ing moderate glide altitude going notch above idle trimming rud der continuous flat circles lift cir cle tightens speed increases go idle shut off model becomes Glid er Dress circle diameters rudder trim locked model will bank steeply go automatic Its easy see spoilers added MK though theyre optional small front-hinged spoilers typi cal blade types designed put Sail plane ground will kill some lift minimum buildup drag MK spoilers set full-open posi tion 60% vertical effect requires steady compensation up elevator goaround aborted landing possible spoilers less full power Use proportional channel radio spoilers can opened degree de sired spoiler system designed produce dethermalized descent Free Flight style thats variable slight limited full Compensating up elevator varies amount spoiler applied model can hold increasing nose-up attitude augment sink desired point STOL descent chooses Its possible fully open spoilers land ing pattern power downwind arriv ing 50 ft high just 100 ft short runway go idle STOL down head runwayor exit thermals approach 600 flight path high altitude anywhere easily hit spot spoiler action limited enough allow final flare safety tech niques fully described Winters arti cle Spoilers Power Febru ary 1986 Model Aviation flying habits MK II dont re quire special description can build youll know what MK II excels close-in maneuvers allowing nervous pilot enough reaction time prevent ships getting ahead him Due airfoil type angular rig ging spoilers appropriate gentlest headwind either model will fly ground cushion extremely low power pilot holds up elevator Winter claims has walked quickly beside MK pilot slows up too much final close ground both ships can stagger around like drunken sail ors until aileron response lost common VEND MOUNTSOn. THE VIBRATION KILLERRubber ft Engine Power Free Flight Display Fail fuel poot In. axes jaolaton 25 00 engine..eo .Control Line Electric Power RIC Airplanes File aCtually tiloWalt angIna'"Our new illustrated 32 page tabloid size catalog mounts Typical oibationtduction TOT, tae85%Tt 01 OOneieteOfUS ft Canada *100 Foreigli $300 moultIS salute four POints 0002ndt'l nn Valley Hobby center washers tubing inStruCtIOnS Sand Sf200 Otrena non Order837-A W Main St Lanadale PA 19448 000 kit GSA PRODUCTS PC 800 3602$ SARASOTA FL 34233 StOOar 3684770 3774252 FL residnts add 72% SaleS faa IRFO5MATIOR sand SASS THE KOMBAT 40 - GREAT R/C SPORT AFPLANE AND WITH SO LITTLE TIME AND MONEY INVESTED YOU CAN REALLY HAVE BALL iTS FULLY AEROBATIC AND EXTREPRELY DURABLE CONSTRUCTED OF ALUtvtIUM AND RUBBERIZED PLASTIC YOU PROVDE THE RADIO AND ENGINE WE SUPPLY EVERYTHING ELSE NO EXTRAS TO BUY 25 ENGINE MAKES GREAT ADVANCED TRAINER SPECIAL INTRODUCTORY OFFER 5 POSTPAID LIST $8995 1880 PINEVIEW MANDEVILLE LA 70448 November 1990 197 620 CRANDALL-LANESVILLE RD CORYDON INDIANA 471 LARGE SELECTION OF REMOTE CONTROL MODEL AIRPLANES AND ACCESSORIES FOR THE PROFESSIONAL A-J US TO JIG AMBROID ARCO RUBBER BANDS BRIDI DA VEYS SYSTEMS CHAMPION CO yE RITE DEVCON SIG SONIC-TRONICS STERLING SULLIVAN TOP FLITE YS ENGINES ZINGER PROPS FK art fiberglass fuSel MADE IN USA PHONE ORDERS 504 626-7840 1-8002647840 SATISFACTION GUARANTEED FLYABLE IN ONE HOUR 1EdiTT FOR ORDERS ONLYJLr7TY 1 -8OO633-7556CODs IN ALABAMA 3473525 COLLECTWELCOME TOP QUALITY FUEL FOR EXPERT OR BEGINNER NO RE-CLAIMED ALCOHOL O METHANE ONLY IS USED Designed tested give top performance both 2 cycle 4-cycle engines ringed Except engines requiring low lubricant content CONTAINS NEW TRULY SPACE AGE ADDITIVE ha deve oped nan outer space vacuum new additive attaches internal metal parts ot engine will reduce nc much 80 reduces heat wear absolute minimum WE HAVE 3 LUBRICANT BLENDS ALL SYNTHETIC OR SYNTHETIC BLEND CASTOR lOur castor new h gh Pu y much c eaner burning castor ALL OUR FUELS CONTAIN ANTIFOAMERS PREVENTERS WEAR ADDITIVES tuel developed priced nd v dus c ub d ect sales market dealer inquiries invited Ord gailon up Mis OK i 4 gailon cases up ALL FUEL EXCEPT 54 GALLON DRUMS SHIPPED FREIGHT PRE-PAID Oniy Coniinentsi USA fTo 3 GalI 23051jTo 63 GaiITO 127 Gal/ Up / Freight Collects 1 Gal4 Gal 24 Gat~64 Gal I28 Gait 54 Gal Drum 50/ 1095 0065057518500 12/1495. 95090085077528000 25%1995 1450 400 1350 1275 47500 50% 2695 22 50 2200 2075 78000 Manufactured MACH-7 PO Box 1201 Enterprise Alabama 36330 condition can landed rud-touch down withtn foot white dot der reassuring know rudder willMiracle Landing/Jollythe runway camera zooming hold heading goof go-roundContinued page 104 tight realism youre sort modeler must Mile Square wasnt closed way have fireworks build standard Stik alibbed walked away epoxyssince flying off adjacent runway piped 60 its realistic enjoyment thatnot holding up Once lower stan-under tightly controlled conditions Sport want either Krackerjacs isdards Krylon model will last for-flying continued active runway pleasant own flyeverthere no lack interested helpers paradox proved true theEach 12 flights last day Epilogue Evans shipped MK IIday 737 made see dif-picture perfect Kent would light fires Winter stab detached itficult shots wed asked like fly-and plane would accelerate lift off taped note Leave off fliesing over edge runway three feetfly Steve Korney tracked 737 over better Winters comment Ifabove ground came off hitch80 mph gear-down over 90 mph gearEvans isnt spoofing would have used ai-Imagine foam glass Krylonup literally stopped traffic nearby lerons elevons reflexed upwardscooting along 80-mph-plus over thestreets drivers spotted what appeared ral control CG atsame ground track time after time Thenbe stricken airliner landing Mile Square 20% Enough alreadythere landings model Continued page 200 PRODUCTS Complete Line Exhaust Systems Tuned Muffled Tuned Pipes Headers uri Mufflers Expansion Mufflers copter Ball Mufflers ialized Exhaust Systems Unsupassed Workmanshin B Paiformance 198 Model Aviation TulnkflvCosnWed Shotioq 1/4 Scale Kits $12995 Epoxy/Glass/Foam Construction Drawings Data Formula 120 Pylon Sport Standoff ScaleKit Price ping Credit Cards WelcomedOhio Residents Add 7%
Edition: Model Aviation - 1990/11
Page Numbers: 83, 84, 85, 86, 87, 88, 196, 197, 198
Krackerjac Mk Mk II favorite oddcouple design team backthis time two-for-one like options build RC sport plane/ trainer combo Mark soars delightfully its higher performance sibling gets excellent marks hot-dogging U Bill Winter Bill Evans VOICE OFFSTAGE go again opposite schools design coau thors have managed second last presumes unlikely collaboration West Coaster Evans loves straight-up 140 0-plus flybys known philoso phy horizontal tails tantamount buggy-whip technology East Coaster pre historic old-timer Bill Winter go-slow airplane watcher thinks straight-up folks harbor hidden rocketry complexes Still found middle ground pro duced Krackerjac MK II Asked Evans would stoop build ing conservative cabin job conspic uous stabilizer Winter would say Whats nice guy like Bill Evans doing place like two collaborated Simitar Slow Motion published January 1987 issue Model Aviation docile flying wing almost easy fly Eaglet time Winters responsiveness Simitar proj ect flabbergasted Evans Winter ever did impose certain conditions First model soarso speed range set 15 80 mph plane fully controllable either rudder aileronsso equipped elevons Because specifications fuselage behind bobtail trailing edge termination extended some eight inches rudder post Since Winter also demanded extended pe riods hands-off flying modest dihedral added Indeed Slow Motion would 720s hands-off initial tap aileron stick save weight ship Krackerjac Mark pictured before its first flight flown Bill Winter couple years before being modified installing spoilers 6-ft-span 40-powered ship has wings stabilizer open-frame construction airfoil thin flat bottomed up main spar has long Phillips entry model has over 6 sq ft area under 19-ozIsq-ft loading will soar easily weak thermals airplane takes off climbs out 1A throttle will consecutive outside loops ttle fly about verted % throttle Bill added spoilers landings could easily made short flying fields Mk Bill Winters newest version Krackerjac seen doing what Bill likes besta slow flyby low altitude low throttle Model can equipped spoilers much like Thermal Soarers help control landings lightly loaded ship Tom Schmitt photo November 1990 83 little headwind model will tly ground cushion extremely low throttle Win ter claims times has able walk quickly beside model still airborne Mk floating its wheels just above grass Tom Schmitt photo tail-dragger protect old man Evans added foot span Aerobatic capability must K&B Veco 19 maximum power after adding second foot span bringing model six feet using 05 15 power performance essentially un changed did Evans Winter join gether second time Krackerjac Winter In 1960 good systems fullhouse control around about five years us could afford single-channel escapement airplanes Lacking elevator control designs addicted ballooning turns wind fly-aways commonplace original 54-in model called K rudder-only control quick-blip high/low throttle Max 15 ended non sense plane published Air Trails kitted Jetco Incidentally throttles time used exhaust stack re strictor coupled butterfly ven turi thin airfoil long Phillips en try secret models controlla bility original handled like multi llent penetration facility per fect touch-and-goes RCs over 40-year period three continue built Antique RC Special published 1948 early-60s Krackerjac reed-systems low-wing Rookie first published Model Airplane News early Sixties later some what modified publication Model Builder Other modelers have frequently im proved upon designs continue Several years ago obtained 6-ft ver sion Krackerjac 40 power plans service built model dozen test flights magazine ex pressed desire publish major manufacturer asked about kit mag wanted perfect pictures unfortu nately Id already marred covering stall spoilers wing efficient 6 sq ft 7A lb gross weight like Glider difficult get ground 300-ft strip Krackerjac soared ease dis covered day turning cross wind leg sixth flight noted no loss altitude did 360 ended up clouds Equipped 40 model demon strated considerable prowess took off climbed one-third throttle could fly inverted respond steering half throttle performed consecutive outside loops half throttle one-third down el evator Yet magazine staff thought plane should have 120 Hard believe told kit company opinion Krackerjac wasnt mainstream hence its best interests aircraft eventually given Doug Pratt converted K&B 40 to Enya four-stroke 46 Pratt has flown three seasons happened mention Bill Evans adding could get clean photos thought should published Evans Curiosity killed cat though find horizontal tails useless appendages Winters strange short-coupled cabin its big stab bottom odd appeal could build onemy way youll seeand fly within week Winter sent print Finding untried modification using semisymmetri cal airfoil 60 power phoned him ask Which would like build said might check out never-built aerobatic version Winter uses lots sticks Im always hurry So simplified fuse went foam balsa-skinned wing stab isnt neutrally stable prefer Winter wont give up measure hands-off control otherwise flies great Winter able join California watching pleased expressions flew per formance version treasured moments Ill never live down project has tail Everybody fly visits shop ribs unmercifully too much shipped model Winter year later Alas reports UPS stress tested wing found wanting Winter So now two airplanes different performance envelope working plan original good new pictures Evans Attempts revise original print tracer ran stone wall project sat 15 months Evans Dont ever get mixed up hair-splitting old-timers Theyll drive up wall kept asking Winter Whats problem Air Force project overruns delays would have provoked Congress hed draw wed done week Finally badgered him drawing incorporating sup plementary drawings decided show cross-options stuff crammed plans could come up least four differ ent ships Maybe should have sold National Geographic Surprise editor gave him green light two 40 x 52-in sheets proposed Winter designate original Mark call Mark II added Buddy East Coast now its own Winter Which build what ex pect Marks Design objectives MK easy piloting rather like 40-powered Senior Falcon Sig Kadet Goldberg Ea gle ability groove well maneuvers better average aerobatics enough reaction time prevent airplanes getting ahead average pi lot slow landings automatic takeoff though its tail-dragger ability ride weak general lift thermal soar Fly 84 Model Aviation close-up shot shows some details Mk built-up wing spoilers shown partially deployed control servos visible under transparent wing covering Steve Kaluf demonstrates short landing tech niques using spoilers plane will land observed attitude reserve flare can abort spoilers deployed Specs spoilers Size opening location etc shown plans tailored safe flight envelope ing techniques discussed end article low wing loading 19 ozI sq ft low drag result consistent ma chine sustains open maneuvers rela tively low power hands-off stability makes relaxed flying What about bigger engine Except improved vertical maneuvers brings added power self-defeating case 60 two-stroke limit youll find yourself doing aerobatics half power potent four-stroke such Enya 60 plenty Watch center-of-gravity such heavy engine An Enya 46 fourstroke does aerobatic maneuvers except advanced such knife-edge flight careful building can achieve gross weight seven pounds Mine turned out 7 lb spoilers two extra servos Some may come 8 lb because some always Dont load up paint Since ship can soar its lightly loaded large wing being equiv alent lower loading smaller wing has significantly higher Reynolds number long low approaches neces saryand critical small field obstacles beneath approach path may overshoot 300-ft strip model too high and/or too fast may wish consider spoiler option Spoilers allow make higher approaches land within first half strip Used front-hinge did create another fun mode flying described later MK Ls open-frame wing thin well large area heavy-handed pilot using oversized engine might overstress model example dive followed abrupt pullout overapplica tion up Evans MK H Winter specified airfoil incidence power 60 en gine version faster far Mark Its also spectacular groovy its closer being neutrally stable MK airplane still safe fly hands-off Winter said wanted two degrees dihedral own insur ance fuselage sides bottom shaped framed prepared ammbly ply gear plate place corner pieces will rounded later cross pIeces glued untrimmed bottom sheet grain running lengthwise side crosspieces trimmed exactly fit Note fishtail butt loint side sheeting above stabilizer saddle docile aircraft rather different fast neutrally stable machines Im used Still found nice fly wrung out Winter California handed controls over him Its measure planes easy handling low-speed abilities cruising about half throttle Winter held light back-pressure steadily ex ecuting towering perfectly round beauti ful loopall touching controls including throttle downside model seemed rails Throughout flight OS 60 gave him power wanted Very slight back trim slower stooging around resulted prolonged slight climb 2A-/3 airfoil ship will climb one-third throttle 60 foam wing balsa skin weighs ex actly same Winters open-frame MK wingfor total model weight 7 lb model robust enough kind flying wing thicker thing increased performance MK H can flown safely anyone aileron experience Like MK will fly ruddernice know since very slow approach rudder last control fail normal aircraft As shown used two exterior-mounted small Futaba servos ailerons Ive used arrangement de signs because its simple speeds up building Winter shocked first saw quickly agreed good way go now has same setup low-wing Desperado Simitar deriva tive anhedral wing reports no trace exhaust dirt servos Winter plans details op tions shown consider before making final decision MK presented basically com plete optional spoilers shown Though spoilers bring interesting dimen sion flying theyre required Cross sections outlines shown MK II wing tail Two versions wing shown Mine slightly modi fied two-bolt-and-dowel attachment Evans wing has four bolts panel can seen Evans external bottommounted servos linkage mod ified panel shows optional standard sin gle-servo arrangement Two profiles show mounting saddle semisymmetri cal wing near side view shows Evans reshaped cabin top four-bolt attachment other shows wing modified dowel two bolts Also shown Evans simpler open nose can substituted com plicated semi-enclosed nose MK Construction Fuselage Two techniques used ease assembly First bottom lies flat workbench Evans used length A-in soft sheeting grain running length wise bottom glued A-in-sq bottom longerons crosspiec es sheeting isnt trimmed off until Left Using front cabin bulkhead ass hg builder glues sides bottom sheeting against bottom side pieces Right assembled fuselage minus top sheeting Note sheet laminations nose Excess bottom sheeting trimmed off point construction technique ensures perfect centerline alignment tail Both Mk Mk II fuselages built same manner November 1990 85 sides top place Drawing centerline bottom sheet ing allows precise positioning rud der post After top longerons side crosspieces have glued fin ished sides fitted top bottom sheeting against bottom longerons Erect main cabin bulkheads before bend ing sides inward aft rear cabin sta tion Second lengths sheet balsa dimen sions given plan laminated graduate inward nose ring avoids awkward bending sides area forward cabin nose rough shaped sanding board progressing coarse medium paper Note different airfoil options re quire different fuselage top rails proper seating semisymmetrical section matching saddle necessitates deeper top rail allow required cutout Likewise choice nose wing op tions influences selection hold-down method consequently number location tapped hold-down blocks dow els etc Tail surfaces selection tail type de termines shape saddle bottom-mounted stabilizer MK built-up stab has cross section basically like two triangles set base base spar position Dress cross section precise contour sanding board sloping edges match shal low triangular shapes beveling edges flat spars Hold sanding Bill Evans showing off trademarks small external aileron servos Bill Winter impressed simplicity now has several models board steadily against edge spar youre working Finish moving board about gradually taking down mate rial along span rather anchoring spot Bolt-on stab mounting recommended easy transportation compact car either tail option epoxied place cer tain remove covering wood-towood joints includes covering laps around bottom saddle assembling vertical surfaces caution trial fit rudder tiller arm allowing sufficient space swing freely prevent metal-to-metal contacts thin neoprene tubing forced over tiller passed through rudder-mounted sheet metal bracket ac cepts tiller align independent finone isnt integral stabclamp thin straightedge hard straight flat piece wood cabin top aligned center marks Bend straightedge wood strip down centerline hole made tiller arm Draw guideline re move strip Evans cut MK II stab light weight foam two tapered halves butt joined centerline after being skinned A6 sheet balsa used own twosided Core Film tape attach skinning Its easy apply works well doesnt lift balsa skin Evans also used own X-Hingeslong sewn hinge strips cut length ironed close hinge gap accept MonoKote well Note leading edge spar glued foam slabs Use yellow glue similar adhesive Sand edges matching contour first achieving flat sloped surface sheeting will glued later rounding off full leading edge Evans glued stab place pre fer bolt yours sure reinforce bolt holes between top bottom sheet ing adequate quantity balsa stalled grain runs vertically Bolts will crush unsupported foam must done prior skinning Adhesives view differences ma terials between two Krackerjac ver sions few notes order wide variety glues can used balsato-balsa joints both authors used Hot Stuff instant well slow-setting because shortens building time Winter finds 3M spray-can contact cement suitable lami nating nose block sheets Epoxy used firewalls wing joiners though Win ter used white glue joiners openframe wing Both Evans Winter used two-sided Core Film skinning Contact cement may substituted make sure its com patible foam 3M spray can vari ety helps job go quickly White glue used attach balsa edge pieces foam cores Winter pro tects inside surfaces nose cavity 86 Model Aviation Above Bill Evans making slow flyby Mk ii Krackerjac crystal-clear air Bishop CA high-performance version equipped OS 60 two-stroke has ailerons rigged fiapperons Look closely youll notice flaps partially deployed Below closer look Mk ii fiapperons clearly visible model has balsaskinned foam core wing stabilizer no spoilers Winter %-1A French-curve airfoil two coats thinned epoxy Landing gear Any standard metal gear satisfactory Halico gear appropri ate size 7A-lb plane bit flimsy anything good landing original Great Planes gear wider tougher Both legs gear bent slight toe-in angle Toe-in eliminates erratic takeoff runs thereby reducing corrections Planes pronounced torque swings will behave bet ter perfectly toe-in No two degrees both toe-in castor recommended standard gear can twisted angle large bench vise Attach gear either two A-in ny lon bolts fitted blind nuts four self-tapping screws nylon bolts will shear semicrash landing broken rem nants can removed heating tip screwdriver Klett plastic gear appeared af ter design produced medium size recommended MK wing open-frame wing can built spoilers men tioned Construction techniques will fa miliar builder experience undertake project nature long Phillips entry airfoil curve leading edge near spar position bottom has characteristics close semisymmetrical section flat portion aft spars makes easy assemble bench Though spacing blocks eliminated its advisable block up leading edge ensure align ment Use standard glue epoxy tach joiners spoilers used note spar webs area front spars clear spoiler horn plans show sizes align ment bellcranks linkage spoiler servo have different servo arm travel indicated plan compensate appropriate holes dont change horn spacing spoiler Washout MK wing achieved bottom-sanding board tip area indicated plan MK II wing Evans built wing foam skinned A6 balsa sheeting airfoil approximate A-2A semisymmetrical section set less incidence MK wing produces less angular difference between wing stab improves aer obatics higher speeds Again Core Film tape X-Hinges used Other hinges may substi tuted made Robart example strong easy usesimply bore holes insert hinges epoxy Since ailerons rather thick fash ion lightest possible balsa Construction differs somewhat used foam stab leading edge built two pieces inner pieces glued flat edge foam sanded before skinning aileron spar re ceives same treatment skinning ex tends over edges After skinning leading edge proper glued front wing Its depth equal inner lead ing edge plus thickness top bottom skins Evans joiner though built A-in ply shallower shown Since UPS performed ultimate stress test changed full-depth joiner shown cut depth foam wing /6 ply slot full-depth joiner easier cut saw tapered por tion joiner will leave gap slot close-up shot Mk Iis tail feathers shows short externai cievis rod runs devises middle hoies arge horns boit visible behind rud der horn retains tail wheei tiiler arm plans show bolt-on arrangement stabilizer its epoxied place plane can filled epoxied scrap foam microballoons mixed epoxy installing two outboard servos wing bottom Evans threaded servo leads through short paper tube buried foam wing before skinning An optional standard single-servo installa tion shown requires servo cavity wood mounting pieces built after skinning panel joining completed November 1990 87 Bill Winter didnt have force smile photo just completed tower ing perfectly round loop half throttle holding gentle stick pressure corrections first flight Evans high-performance Mk ii business end Evans Mk Ii Its OS 60 swinging 11 x 7 Zinger prop simple open-nose configuration shown option plans profile less deep Winters Mk version windshield carved block balsa Vertical-grain blocks un der two wing hold-down bolts prevent crushing foam wing skin Note ex haust diverter made copper plumbing elbow retained common hose clamp Block up panel turn proper dihedral aligning wing root edge workbench sanding board can used smooth matching root sections Some foam removed ac commodate smaller front rear join ers Trial fit panels joiners until fit perfect Before permanently inserting joiners work epoxy evenly slots smooth evenly over joiners Cover center joints M-oz glass cloth Attach cloth epoxy rubbing out excess outer edges wiping off residue wing tips sloped sanding board Make plywood jig piece check ing proper angle tips made soft sheeting overlap top bottom skin leave excess Block sand match wing top bottom Covering Though iron-on coverings easy use recommend textured mate rial MK companies sell dif ferent varieties often can painted MK used silk/rayon applied buty rate fuselage finished two coats K&B epoxy paint wings tail however covered Super Mono Kote Though excellent popular prod uct turned out unsuitable large-area open-frame wing ship size weight landing made considerable vertical impact during spoiler experiments MK dead weight wings flexed down structural damage split covering chordwise edge edge Covering sheeted fuselage A-oz glass cloth attached K&B satin brush ing epoxy provides strength good finish imperviousness raw fuel glass cloth brushes out flat pulling follows curves corners After allow ing stand overnight can sanded beautifully fine-grade paper given second coat K&B epoxy col ored paint wont leave trace brush mark single coat works well two sufficient Other material re quired open stab wing Super MonoKote worked well MK II its wing being solid rather openframe construction Evans loves effect orange accented dark blue striping MK has red fuselage orange wings stab silver vertical red-orange combination happenstance Winter 25-ft roll orange hand Yellow would make less fiery contrast red background Flying Anyone building mod els already knows flyor should notes follow intended famil iarize handling characteristics Winters Evans modelsa preflight handoff speak primary focus MK Since MK intended fly wing power spectacular vertical maneuvers high-rate rolls expected craft wasnt designed per form knife-edge categoryresponses realistic stick pressures pilot MK delivers some nice performance indeed Pilots full-size air planes will sense familiar feedback fact flying model rather like being cockpit aircraft does would expect Because flies wing Mark will surprise certain modes course vertical performance would improve 60 engine much power would disadvantage other re spects bigger engine would have throttled back considerably time using high power climb ma neuvers full power heavy down trim would required due lift available would need either fly backstick remove considerable down trim dur ing approaches landings K&B 40 MK lifts off one-third power out pilots touching elevator theres no need two-thirds throttle point Incidentally 10 x 6 pro peller usual choice 11 x 5 wood prop better matched models aero batics proper center-of-gravity CG loca tion flat-bottomed airfoil section 25% chord Though pilots ac customed trimming 33% requires down trim cruising heavier control deflections inverted outside loops forward position gives solid feeling better penetration less bouncing around wind light wing load ings ride bumpily wind Approaches positive groove good test appropriateness CG location aerobatics perform outside loop constant elevator power ship buttonhooksthat tightens up during last quarter maneuver straightens back level flight lower its original altitudethis means its too nose-heavy Because model both short-coupled tail-dragger full up elevator recom mended slow taxiing grassespe cially grass long ragged begin takeoff advance throttle slowly smoothlynever abruptlywhile continu ing hold up elevator short distance typically 10 ft Actually lower power Continued page 196 88 Model Aviation Bill Evans baisa4kinned foam-core Mk ii wings root left has yet slotted joiner pians shows fuii-depth joiner requiring presiotting foam Evens inserts deep joiner through bottom slot including bottom skin cutout wing tip right msde soft sheet balsa cut oversize sanded flush top bottom sheeting foam-core stabilizer halves Evans Mk ii have skinned balsa sheeting ready joined center epoxy tips made sheet balsa --- * fl5 E Main Northvlfle Ml 481 67 Special Fast Turnaround Now Available CALL Frequency Conversion $4000 Includes Crystals Certification Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royai Tower HobbiesWorld Engines Spectrum Ana lyzers Cali brated Test struments Large Inventory R/C Parts Crystals Self I Addressed Envelope Ill Fly What Fix LeI ZAP UNIVERSITY COLLEGE OF GLUE KNOWLEDGE turn use small medical syringe meter fuel engine Cardinal will fly out sight full tank measuring fuel important Limit first test flights short engine runs five seconds stretching long practical ie long care run af ter model once things look safe Normally start priming engine hooking up battery Once prime fuel left tank run out feed measured amount check wind direc tion start engine needle valve preset produce slow run once its running its time launch its gusty day Cardinal probably ready its trim dihedral model will handle fair amount wind Make sure shes launched directly wind just slightly off right Sport flying should always much fun Krackerjac/Wi nter-Evans Continued page 90 used begin roll followed smooth steady advancing throt tle pilot wont need bold up take off allowing roll develop bit before going higher power increase airspeed point rudder has good bite steering tail-dragger steering control low speeds derives tail wheel much rud der quick surge power allowed lift tail instantly airplane will lose steering power due loss tail wheel trac tion 5-mph headwind MK will climb quickly landing pattern height one-third power power expect airplane climb rapidly fly wing two degrees dihedral permits free flight hands-off stability yielding continu ous turns either aileron rudder out compromising wingovers etc stooging around wide turns can tight ened much desired touch up el evator nose wont drop return neutral roll out plane will nose-up invert MK raise nose slightly say 100 half roll al lows time feel matching down el evator before nose drops Powered 40 engine model will sustain invert ed maneuversincluding steering figure eights etcat two-thirds power one-half going down no two-thirds go ing down circumstances Three consecutive concentric outside loops can done flying off top half power one-third one-half go ing down power speed opens up outside increasing loadings up side possibly causing twisting out ship has area thats intended used Landing approaches long airUPS US Mail Federal Express OOD Mastercard Visa Acce ted YOU WONT GET STUNG ON OUR NEW STINGER ARF Fuselage Length 525 Wing Span 84 Rec Engine Size 12 42 cu inArea 1596 sq Flying Weight 14 lbs & upRadio Channels 4 Available favorite Hobby Dealer Replacement parts available Dealer distributor inquiries invited Write today information LANIER RC PO Box 458 ood GA 30566 532-6401 Made U S 196 Model Aviation LISTED FORACOMPLETh PLEASE SEND STAMPED SELF-AL mSAATL FOR YOUR BUSINESS _____I~\I plane shows surprising ability keep coming makes really good idle essen tial bigger lower pitched prop provides bit braking Because clean ap proach use stick pressure rather movements up elevator begin flareotherwise youll go out other side Slowly build up sink touchdown gradually increasing up pressure As mentioned ship soars easily has soared out turn cross wind adding power simply trim ming rudder flat wide circles Nor mally soaring MK done climb ing moderate glide altitude going notch above idle trimming rud der continuous flat circles lift cir cle tightens speed increases go idle shut off model becomes Glid er Dress circle diameters rudder trim locked model will bank steeply go automatic Its easy see spoilers added MK though theyre optional small front-hinged spoilers typi cal blade types designed put Sail plane ground will kill some lift minimum buildup drag MK spoilers set full-open posi tion 60% vertical effect requires steady compensation up elevator goaround aborted landing possible spoilers less full power Use proportional channel radio spoilers can opened degree de sired spoiler system designed produce dethermalized descent Free Flight style thats variable slight limited full Compensating up elevator varies amount spoiler applied model can hold increasing nose-up attitude augment sink desired point STOL descent chooses Its possible fully open spoilers land ing pattern power downwind arriv ing 50 ft high just 100 ft short runway go idle STOL down head runwayor exit thermals approach 600 flight path high altitude anywhere easily hit spot spoiler action limited enough allow final flare safety tech niques fully described Winters arti cle Spoilers Power Febru ary 1986 Model Aviation flying habits MK II dont re quire special description can build youll know what MK II excels close-in maneuvers allowing nervous pilot enough reaction time prevent ships getting ahead him Due airfoil type angular rig ging spoilers appropriate gentlest headwind either model will fly ground cushion extremely low power pilot holds up elevator Winter claims has walked quickly beside MK pilot slows up too much final close ground both ships can stagger around like drunken sail ors until aileron response lost common VEND MOUNTSOn. THE VIBRATION KILLERRubber ft Engine Power Free Flight Display Fail fuel poot In. axes jaolaton 25 00 engine..eo .Control Line Electric Power RIC Airplanes File aCtually tiloWalt angIna'"Our new illustrated 32 page tabloid size catalog mounts Typical oibationtduction TOT, tae85%Tt 01 OOneieteOfUS ft Canada *100 Foreigli $300 moultIS salute four POints 0002ndt'l nn Valley Hobby center washers tubing inStruCtIOnS Sand Sf200 Otrena non Order837-A W Main St Lanadale PA 19448 000 kit GSA PRODUCTS PC 800 3602$ SARASOTA FL 34233 StOOar 3684770 3774252 FL residnts add 72% SaleS faa IRFO5MATIOR sand SASS THE KOMBAT 40 - GREAT R/C SPORT AFPLANE AND WITH SO LITTLE TIME AND MONEY INVESTED YOU CAN REALLY HAVE BALL iTS FULLY AEROBATIC AND EXTREPRELY DURABLE CONSTRUCTED OF ALUtvtIUM AND RUBBERIZED PLASTIC YOU PROVDE THE RADIO AND ENGINE WE SUPPLY EVERYTHING ELSE NO EXTRAS TO BUY 25 ENGINE MAKES GREAT ADVANCED TRAINER SPECIAL INTRODUCTORY OFFER 5 POSTPAID LIST $8995 1880 PINEVIEW MANDEVILLE LA 70448 November 1990 197 620 CRANDALL-LANESVILLE RD CORYDON INDIANA 471 LARGE SELECTION OF REMOTE CONTROL MODEL AIRPLANES AND ACCESSORIES FOR THE PROFESSIONAL A-J US TO JIG AMBROID ARCO RUBBER BANDS BRIDI DA VEYS SYSTEMS CHAMPION CO yE RITE DEVCON SIG SONIC-TRONICS STERLING SULLIVAN TOP FLITE YS ENGINES ZINGER PROPS FK art fiberglass fuSel MADE IN USA PHONE ORDERS 504 626-7840 1-8002647840 SATISFACTION GUARANTEED FLYABLE IN ONE HOUR 1EdiTT FOR ORDERS ONLYJLr7TY 1 -8OO633-7556CODs IN ALABAMA 3473525 COLLECTWELCOME TOP QUALITY FUEL FOR EXPERT OR BEGINNER NO RE-CLAIMED ALCOHOL O METHANE ONLY IS USED Designed tested give top performance both 2 cycle 4-cycle engines ringed Except engines requiring low lubricant content CONTAINS NEW TRULY SPACE AGE ADDITIVE ha deve oped nan outer space vacuum new additive attaches internal metal parts ot engine will reduce nc much 80 reduces heat wear absolute minimum WE HAVE 3 LUBRICANT BLENDS ALL SYNTHETIC OR SYNTHETIC BLEND CASTOR lOur castor new h gh Pu y much c eaner burning castor ALL OUR FUELS CONTAIN ANTIFOAMERS PREVENTERS WEAR ADDITIVES tuel developed priced nd v dus c ub d ect sales market dealer inquiries invited Ord gailon up Mis OK i 4 gailon cases up ALL FUEL EXCEPT 54 GALLON DRUMS SHIPPED FREIGHT PRE-PAID Oniy Coniinentsi USA fTo 3 GalI 23051jTo 63 GaiITO 127 Gal/ Up / Freight Collects 1 Gal4 Gal 24 Gat~64 Gal I28 Gait 54 Gal Drum 50/ 1095 0065057518500 12/1495. 95090085077528000 25%1995 1450 400 1350 1275 47500 50% 2695 22 50 2200 2075 78000 Manufactured MACH-7 PO Box 1201 Enterprise Alabama 36330 condition can landed rud-touch down withtn foot white dot der reassuring know rudder willMiracle Landing/Jollythe runway camera zooming hold heading goof go-roundContinued page 104 tight realism youre sort modeler must Mile Square wasnt closed way have fireworks build standard Stik alibbed walked away epoxyssince flying off adjacent runway piped 60 its realistic enjoyment thatnot holding up Once lower stan-under tightly controlled conditions Sport want either Krackerjacs isdards Krylon model will last for-flying continued active runway pleasant own flyeverthere no lack interested helpers paradox proved true theEach 12 flights last day Epilogue Evans shipped MK IIday 737 made see dif-picture perfect Kent would light fires Winter stab detached itficult shots wed asked like fly-and plane would accelerate lift off taped note Leave off fliesing over edge runway three feetfly Steve Korney tracked 737 over better Winters comment Ifabove ground came off hitch80 mph gear-down over 90 mph gearEvans isnt spoofing would have used ai-Imagine foam glass Krylonup literally stopped traffic nearby lerons elevons reflexed upwardscooting along 80-mph-plus over thestreets drivers spotted what appeared ral control CG atsame ground track time after time Thenbe stricken airliner landing Mile Square 20% Enough alreadythere landings model Continued page 200 PRODUCTS Complete Line Exhaust Systems Tuned Muffled Tuned Pipes Headers uri Mufflers Expansion Mufflers copter Ball Mufflers ialized Exhaust Systems Unsupassed Workmanshin B Paiformance 198 Model Aviation TulnkflvCosnWed Shotioq 1/4 Scale Kits $12995 Epoxy/Glass/Foam Construction Drawings Data Formula 120 Pylon Sport Standoff ScaleKit Price ping Credit Cards WelcomedOhio Residents Add 7%
Edition: Model Aviation - 1990/11
Page Numbers: 83, 84, 85, 86, 87, 88, 196, 197, 198
Krackerjac Mk Mk II favorite oddcouple design team backthis time two-for-one like options build RC sport plane/ trainer combo Mark soars delightfully its higher performance sibling gets excellent marks hot-dogging U Bill Winter Bill Evans VOICE OFFSTAGE go again opposite schools design coau thors have managed second last presumes unlikely collaboration West Coaster Evans loves straight-up 140 0-plus flybys known philoso phy horizontal tails tantamount buggy-whip technology East Coaster pre historic old-timer Bill Winter go-slow airplane watcher thinks straight-up folks harbor hidden rocketry complexes Still found middle ground pro duced Krackerjac MK II Asked Evans would stoop build ing conservative cabin job conspic uous stabilizer Winter would say Whats nice guy like Bill Evans doing place like two collaborated Simitar Slow Motion published January 1987 issue Model Aviation docile flying wing almost easy fly Eaglet time Winters responsiveness Simitar proj ect flabbergasted Evans Winter ever did impose certain conditions First model soarso speed range set 15 80 mph plane fully controllable either rudder aileronsso equipped elevons Because specifications fuselage behind bobtail trailing edge termination extended some eight inches rudder post Since Winter also demanded extended pe riods hands-off flying modest dihedral added Indeed Slow Motion would 720s hands-off initial tap aileron stick save weight ship Krackerjac Mark pictured before its first flight flown Bill Winter couple years before being modified installing spoilers 6-ft-span 40-powered ship has wings stabilizer open-frame construction airfoil thin flat bottomed up main spar has long Phillips entry model has over 6 sq ft area under 19-ozIsq-ft loading will soar easily weak thermals airplane takes off climbs out 1A throttle will consecutive outside loops ttle fly about verted % throttle Bill added spoilers landings could easily made short flying fields Mk Bill Winters newest version Krackerjac seen doing what Bill likes besta slow flyby low altitude low throttle Model can equipped spoilers much like Thermal Soarers help control landings lightly loaded ship Tom Schmitt photo November 1990 83 little headwind model will tly ground cushion extremely low throttle Win ter claims times has able walk quickly beside model still airborne Mk floating its wheels just above grass Tom Schmitt photo tail-dragger protect old man Evans added foot span Aerobatic capability must K&B Veco 19 maximum power after adding second foot span bringing model six feet using 05 15 power performance essentially un changed did Evans Winter join gether second time Krackerjac Winter In 1960 good systems fullhouse control around about five years us could afford single-channel escapement airplanes Lacking elevator control designs addicted ballooning turns wind fly-aways commonplace original 54-in model called K rudder-only control quick-blip high/low throttle Max 15 ended non sense plane published Air Trails kitted Jetco Incidentally throttles time used exhaust stack re strictor coupled butterfly ven turi thin airfoil long Phillips en try secret models controlla bility original handled like multi llent penetration facility per fect touch-and-goes RCs over 40-year period three continue built Antique RC Special published 1948 early-60s Krackerjac reed-systems low-wing Rookie first published Model Airplane News early Sixties later some what modified publication Model Builder Other modelers have frequently im proved upon designs continue Several years ago obtained 6-ft ver sion Krackerjac 40 power plans service built model dozen test flights magazine ex pressed desire publish major manufacturer asked about kit mag wanted perfect pictures unfortu nately Id already marred covering stall spoilers wing efficient 6 sq ft 7A lb gross weight like Glider difficult get ground 300-ft strip Krackerjac soared ease dis covered day turning cross wind leg sixth flight noted no loss altitude did 360 ended up clouds Equipped 40 model demon strated considerable prowess took off climbed one-third throttle could fly inverted respond steering half throttle performed consecutive outside loops half throttle one-third down el evator Yet magazine staff thought plane should have 120 Hard believe told kit company opinion Krackerjac wasnt mainstream hence its best interests aircraft eventually given Doug Pratt converted K&B 40 to Enya four-stroke 46 Pratt has flown three seasons happened mention Bill Evans adding could get clean photos thought should published Evans Curiosity killed cat though find horizontal tails useless appendages Winters strange short-coupled cabin its big stab bottom odd appeal could build onemy way youll seeand fly within week Winter sent print Finding untried modification using semisymmetri cal airfoil 60 power phoned him ask Which would like build said might check out never-built aerobatic version Winter uses lots sticks Im always hurry So simplified fuse went foam balsa-skinned wing stab isnt neutrally stable prefer Winter wont give up measure hands-off control otherwise flies great Winter able join California watching pleased expressions flew per formance version treasured moments Ill never live down project has tail Everybody fly visits shop ribs unmercifully too much shipped model Winter year later Alas reports UPS stress tested wing found wanting Winter So now two airplanes different performance envelope working plan original good new pictures Evans Attempts revise original print tracer ran stone wall project sat 15 months Evans Dont ever get mixed up hair-splitting old-timers Theyll drive up wall kept asking Winter Whats problem Air Force project overruns delays would have provoked Congress hed draw wed done week Finally badgered him drawing incorporating sup plementary drawings decided show cross-options stuff crammed plans could come up least four differ ent ships Maybe should have sold National Geographic Surprise editor gave him green light two 40 x 52-in sheets proposed Winter designate original Mark call Mark II added Buddy East Coast now its own Winter Which build what ex pect Marks Design objectives MK easy piloting rather like 40-powered Senior Falcon Sig Kadet Goldberg Ea gle ability groove well maneuvers better average aerobatics enough reaction time prevent airplanes getting ahead average pi lot slow landings automatic takeoff though its tail-dragger ability ride weak general lift thermal soar Fly 84 Model Aviation close-up shot shows some details Mk built-up wing spoilers shown partially deployed control servos visible under transparent wing covering Steve Kaluf demonstrates short landing tech niques using spoilers plane will land observed attitude reserve flare can abort spoilers deployed Specs spoilers Size opening location etc shown plans tailored safe flight envelope ing techniques discussed end article low wing loading 19 ozI sq ft low drag result consistent ma chine sustains open maneuvers rela tively low power hands-off stability makes relaxed flying What about bigger engine Except improved vertical maneuvers brings added power self-defeating case 60 two-stroke limit youll find yourself doing aerobatics half power potent four-stroke such Enya 60 plenty Watch center-of-gravity such heavy engine An Enya 46 fourstroke does aerobatic maneuvers except advanced such knife-edge flight careful building can achieve gross weight seven pounds Mine turned out 7 lb spoilers two extra servos Some may come 8 lb because some always Dont load up paint Since ship can soar its lightly loaded large wing being equiv alent lower loading smaller wing has significantly higher Reynolds number long low approaches neces saryand critical small field obstacles beneath approach path may overshoot 300-ft strip model too high and/or too fast may wish consider spoiler option Spoilers allow make higher approaches land within first half strip Used front-hinge did create another fun mode flying described later MK Ls open-frame wing thin well large area heavy-handed pilot using oversized engine might overstress model example dive followed abrupt pullout overapplica tion up Evans MK H Winter specified airfoil incidence power 60 en gine version faster far Mark Its also spectacular groovy its closer being neutrally stable MK airplane still safe fly hands-off Winter said wanted two degrees dihedral own insur ance fuselage sides bottom shaped framed prepared ammbly ply gear plate place corner pieces will rounded later cross pIeces glued untrimmed bottom sheet grain running lengthwise side crosspieces trimmed exactly fit Note fishtail butt loint side sheeting above stabilizer saddle docile aircraft rather different fast neutrally stable machines Im used Still found nice fly wrung out Winter California handed controls over him Its measure planes easy handling low-speed abilities cruising about half throttle Winter held light back-pressure steadily ex ecuting towering perfectly round beauti ful loopall touching controls including throttle downside model seemed rails Throughout flight OS 60 gave him power wanted Very slight back trim slower stooging around resulted prolonged slight climb 2A-/3 airfoil ship will climb one-third throttle 60 foam wing balsa skin weighs ex actly same Winters open-frame MK wingfor total model weight 7 lb model robust enough kind flying wing thicker thing increased performance MK H can flown safely anyone aileron experience Like MK will fly ruddernice know since very slow approach rudder last control fail normal aircraft As shown used two exterior-mounted small Futaba servos ailerons Ive used arrangement de signs because its simple speeds up building Winter shocked first saw quickly agreed good way go now has same setup low-wing Desperado Simitar deriva tive anhedral wing reports no trace exhaust dirt servos Winter plans details op tions shown consider before making final decision MK presented basically com plete optional spoilers shown Though spoilers bring interesting dimen sion flying theyre required Cross sections outlines shown MK II wing tail Two versions wing shown Mine slightly modi fied two-bolt-and-dowel attachment Evans wing has four bolts panel can seen Evans external bottommounted servos linkage mod ified panel shows optional standard sin gle-servo arrangement Two profiles show mounting saddle semisymmetri cal wing near side view shows Evans reshaped cabin top four-bolt attachment other shows wing modified dowel two bolts Also shown Evans simpler open nose can substituted com plicated semi-enclosed nose MK Construction Fuselage Two techniques used ease assembly First bottom lies flat workbench Evans used length A-in soft sheeting grain running length wise bottom glued A-in-sq bottom longerons crosspiec es sheeting isnt trimmed off until Left Using front cabin bulkhead ass hg builder glues sides bottom sheeting against bottom side pieces Right assembled fuselage minus top sheeting Note sheet laminations nose Excess bottom sheeting trimmed off point construction technique ensures perfect centerline alignment tail Both Mk Mk II fuselages built same manner November 1990 85 sides top place Drawing centerline bottom sheet ing allows precise positioning rud der post After top longerons side crosspieces have glued fin ished sides fitted top bottom sheeting against bottom longerons Erect main cabin bulkheads before bend ing sides inward aft rear cabin sta tion Second lengths sheet balsa dimen sions given plan laminated graduate inward nose ring avoids awkward bending sides area forward cabin nose rough shaped sanding board progressing coarse medium paper Note different airfoil options re quire different fuselage top rails proper seating semisymmetrical section matching saddle necessitates deeper top rail allow required cutout Likewise choice nose wing op tions influences selection hold-down method consequently number location tapped hold-down blocks dow els etc Tail surfaces selection tail type de termines shape saddle bottom-mounted stabilizer MK built-up stab has cross section basically like two triangles set base base spar position Dress cross section precise contour sanding board sloping edges match shal low triangular shapes beveling edges flat spars Hold sanding Bill Evans showing off trademarks small external aileron servos Bill Winter impressed simplicity now has several models board steadily against edge spar youre working Finish moving board about gradually taking down mate rial along span rather anchoring spot Bolt-on stab mounting recommended easy transportation compact car either tail option epoxied place cer tain remove covering wood-towood joints includes covering laps around bottom saddle assembling vertical surfaces caution trial fit rudder tiller arm allowing sufficient space swing freely prevent metal-to-metal contacts thin neoprene tubing forced over tiller passed through rudder-mounted sheet metal bracket ac cepts tiller align independent finone isnt integral stabclamp thin straightedge hard straight flat piece wood cabin top aligned center marks Bend straightedge wood strip down centerline hole made tiller arm Draw guideline re move strip Evans cut MK II stab light weight foam two tapered halves butt joined centerline after being skinned A6 sheet balsa used own twosided Core Film tape attach skinning Its easy apply works well doesnt lift balsa skin Evans also used own X-Hingeslong sewn hinge strips cut length ironed close hinge gap accept MonoKote well Note leading edge spar glued foam slabs Use yellow glue similar adhesive Sand edges matching contour first achieving flat sloped surface sheeting will glued later rounding off full leading edge Evans glued stab place pre fer bolt yours sure reinforce bolt holes between top bottom sheet ing adequate quantity balsa stalled grain runs vertically Bolts will crush unsupported foam must done prior skinning Adhesives view differences ma terials between two Krackerjac ver sions few notes order wide variety glues can used balsato-balsa joints both authors used Hot Stuff instant well slow-setting because shortens building time Winter finds 3M spray-can contact cement suitable lami nating nose block sheets Epoxy used firewalls wing joiners though Win ter used white glue joiners openframe wing Both Evans Winter used two-sided Core Film skinning Contact cement may substituted make sure its com patible foam 3M spray can vari ety helps job go quickly White glue used attach balsa edge pieces foam cores Winter pro tects inside surfaces nose cavity 86 Model Aviation Above Bill Evans making slow flyby Mk ii Krackerjac crystal-clear air Bishop CA high-performance version equipped OS 60 two-stroke has ailerons rigged fiapperons Look closely youll notice flaps partially deployed Below closer look Mk ii fiapperons clearly visible model has balsaskinned foam core wing stabilizer no spoilers Winter %-1A French-curve airfoil two coats thinned epoxy Landing gear Any standard metal gear satisfactory Halico gear appropri ate size 7A-lb plane bit flimsy anything good landing original Great Planes gear wider tougher Both legs gear bent slight toe-in angle Toe-in eliminates erratic takeoff runs thereby reducing corrections Planes pronounced torque swings will behave bet ter perfectly toe-in No two degrees both toe-in castor recommended standard gear can twisted angle large bench vise Attach gear either two A-in ny lon bolts fitted blind nuts four self-tapping screws nylon bolts will shear semicrash landing broken rem nants can removed heating tip screwdriver Klett plastic gear appeared af ter design produced medium size recommended MK wing open-frame wing can built spoilers men tioned Construction techniques will fa miliar builder experience undertake project nature long Phillips entry airfoil curve leading edge near spar position bottom has characteristics close semisymmetrical section flat portion aft spars makes easy assemble bench Though spacing blocks eliminated its advisable block up leading edge ensure align ment Use standard glue epoxy tach joiners spoilers used note spar webs area front spars clear spoiler horn plans show sizes align ment bellcranks linkage spoiler servo have different servo arm travel indicated plan compensate appropriate holes dont change horn spacing spoiler Washout MK wing achieved bottom-sanding board tip area indicated plan MK II wing Evans built wing foam skinned A6 balsa sheeting airfoil approximate A-2A semisymmetrical section set less incidence MK wing produces less angular difference between wing stab improves aer obatics higher speeds Again Core Film tape X-Hinges used Other hinges may substi tuted made Robart example strong easy usesimply bore holes insert hinges epoxy Since ailerons rather thick fash ion lightest possible balsa Construction differs somewhat used foam stab leading edge built two pieces inner pieces glued flat edge foam sanded before skinning aileron spar re ceives same treatment skinning ex tends over edges After skinning leading edge proper glued front wing Its depth equal inner lead ing edge plus thickness top bottom skins Evans joiner though built A-in ply shallower shown Since UPS performed ultimate stress test changed full-depth joiner shown cut depth foam wing /6 ply slot full-depth joiner easier cut saw tapered por tion joiner will leave gap slot close-up shot Mk Iis tail feathers shows short externai cievis rod runs devises middle hoies arge horns boit visible behind rud der horn retains tail wheei tiiler arm plans show bolt-on arrangement stabilizer its epoxied place plane can filled epoxied scrap foam microballoons mixed epoxy installing two outboard servos wing bottom Evans threaded servo leads through short paper tube buried foam wing before skinning An optional standard single-servo installa tion shown requires servo cavity wood mounting pieces built after skinning panel joining completed November 1990 87 Bill Winter didnt have force smile photo just completed tower ing perfectly round loop half throttle holding gentle stick pressure corrections first flight Evans high-performance Mk ii business end Evans Mk Ii Its OS 60 swinging 11 x 7 Zinger prop simple open-nose configuration shown option plans profile less deep Winters Mk version windshield carved block balsa Vertical-grain blocks un der two wing hold-down bolts prevent crushing foam wing skin Note ex haust diverter made copper plumbing elbow retained common hose clamp Block up panel turn proper dihedral aligning wing root edge workbench sanding board can used smooth matching root sections Some foam removed ac commodate smaller front rear join ers Trial fit panels joiners until fit perfect Before permanently inserting joiners work epoxy evenly slots smooth evenly over joiners Cover center joints M-oz glass cloth Attach cloth epoxy rubbing out excess outer edges wiping off residue wing tips sloped sanding board Make plywood jig piece check ing proper angle tips made soft sheeting overlap top bottom skin leave excess Block sand match wing top bottom Covering Though iron-on coverings easy use recommend textured mate rial MK companies sell dif ferent varieties often can painted MK used silk/rayon applied buty rate fuselage finished two coats K&B epoxy paint wings tail however covered Super Mono Kote Though excellent popular prod uct turned out unsuitable large-area open-frame wing ship size weight landing made considerable vertical impact during spoiler experiments MK dead weight wings flexed down structural damage split covering chordwise edge edge Covering sheeted fuselage A-oz glass cloth attached K&B satin brush ing epoxy provides strength good finish imperviousness raw fuel glass cloth brushes out flat pulling follows curves corners After allow ing stand overnight can sanded beautifully fine-grade paper given second coat K&B epoxy col ored paint wont leave trace brush mark single coat works well two sufficient Other material re quired open stab wing Super MonoKote worked well MK II its wing being solid rather openframe construction Evans loves effect orange accented dark blue striping MK has red fuselage orange wings stab silver vertical red-orange combination happenstance Winter 25-ft roll orange hand Yellow would make less fiery contrast red background Flying Anyone building mod els already knows flyor should notes follow intended famil iarize handling characteristics Winters Evans modelsa preflight handoff speak primary focus MK Since MK intended fly wing power spectacular vertical maneuvers high-rate rolls expected craft wasnt designed per form knife-edge categoryresponses realistic stick pressures pilot MK delivers some nice performance indeed Pilots full-size air planes will sense familiar feedback fact flying model rather like being cockpit aircraft does would expect Because flies wing Mark will surprise certain modes course vertical performance would improve 60 engine much power would disadvantage other re spects bigger engine would have throttled back considerably time using high power climb ma neuvers full power heavy down trim would required due lift available would need either fly backstick remove considerable down trim dur ing approaches landings K&B 40 MK lifts off one-third power out pilots touching elevator theres no need two-thirds throttle point Incidentally 10 x 6 pro peller usual choice 11 x 5 wood prop better matched models aero batics proper center-of-gravity CG loca tion flat-bottomed airfoil section 25% chord Though pilots ac customed trimming 33% requires down trim cruising heavier control deflections inverted outside loops forward position gives solid feeling better penetration less bouncing around wind light wing load ings ride bumpily wind Approaches positive groove good test appropriateness CG location aerobatics perform outside loop constant elevator power ship buttonhooksthat tightens up during last quarter maneuver straightens back level flight lower its original altitudethis means its too nose-heavy Because model both short-coupled tail-dragger full up elevator recom mended slow taxiing grassespe cially grass long ragged begin takeoff advance throttle slowly smoothlynever abruptlywhile continu ing hold up elevator short distance typically 10 ft Actually lower power Continued page 196 88 Model Aviation Bill Evans baisa4kinned foam-core Mk ii wings root left has yet slotted joiner pians shows fuii-depth joiner requiring presiotting foam Evens inserts deep joiner through bottom slot including bottom skin cutout wing tip right msde soft sheet balsa cut oversize sanded flush top bottom sheeting foam-core stabilizer halves Evans Mk ii have skinned balsa sheeting ready joined center epoxy tips made sheet balsa --- * fl5 E Main Northvlfle Ml 481 67 Special Fast Turnaround Now Available CALL Frequency Conversion $4000 Includes Crystals Certification Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royai Tower HobbiesWorld Engines Spectrum Ana lyzers Cali brated Test struments Large Inventory R/C Parts Crystals Self I Addressed Envelope Ill Fly What Fix LeI ZAP UNIVERSITY COLLEGE OF GLUE KNOWLEDGE turn use small medical syringe meter fuel engine Cardinal will fly out sight full tank measuring fuel important Limit first test flights short engine runs five seconds stretching long practical ie long care run af ter model once things look safe Normally start priming engine hooking up battery Once prime fuel left tank run out feed measured amount check wind direc tion start engine needle valve preset produce slow run once its running its time launch its gusty day Cardinal probably ready its trim dihedral model will handle fair amount wind Make sure shes launched directly wind just slightly off right Sport flying should always much fun Krackerjac/Wi nter-Evans Continued page 90 used begin roll followed smooth steady advancing throt tle pilot wont need bold up take off allowing roll develop bit before going higher power increase airspeed point rudder has good bite steering tail-dragger steering control low speeds derives tail wheel much rud der quick surge power allowed lift tail instantly airplane will lose steering power due loss tail wheel trac tion 5-mph headwind MK will climb quickly landing pattern height one-third power power expect airplane climb rapidly fly wing two degrees dihedral permits free flight hands-off stability yielding continu ous turns either aileron rudder out compromising wingovers etc stooging around wide turns can tight ened much desired touch up el evator nose wont drop return neutral roll out plane will nose-up invert MK raise nose slightly say 100 half roll al lows time feel matching down el evator before nose drops Powered 40 engine model will sustain invert ed maneuversincluding steering figure eights etcat two-thirds power one-half going down no two-thirds go ing down circumstances Three consecutive concentric outside loops can done flying off top half power one-third one-half go ing down power speed opens up outside increasing loadings up side possibly causing twisting out ship has area thats intended used Landing approaches long airUPS US Mail Federal Express OOD Mastercard Visa Acce ted YOU WONT GET STUNG ON OUR NEW STINGER ARF Fuselage Length 525 Wing Span 84 Rec Engine Size 12 42 cu inArea 1596 sq Flying Weight 14 lbs & upRadio Channels 4 Available favorite Hobby Dealer Replacement parts available Dealer distributor inquiries invited Write today information LANIER RC PO Box 458 ood GA 30566 532-6401 Made U S 196 Model Aviation LISTED FORACOMPLETh PLEASE SEND STAMPED SELF-AL mSAATL FOR YOUR BUSINESS _____I~\I plane shows surprising ability keep coming makes really good idle essen tial bigger lower pitched prop provides bit braking Because clean ap proach use stick pressure rather movements up elevator begin flareotherwise youll go out other side Slowly build up sink touchdown gradually increasing up pressure As mentioned ship soars easily has soared out turn cross wind adding power simply trim ming rudder flat wide circles Nor mally soaring MK done climb ing moderate glide altitude going notch above idle trimming rud der continuous flat circles lift cir cle tightens speed increases go idle shut off model becomes Glid er Dress circle diameters rudder trim locked model will bank steeply go automatic Its easy see spoilers added MK though theyre optional small front-hinged spoilers typi cal blade types designed put Sail plane ground will kill some lift minimum buildup drag MK spoilers set full-open posi tion 60% vertical effect requires steady compensation up elevator goaround aborted landing possible spoilers less full power Use proportional channel radio spoilers can opened degree de sired spoiler system designed produce dethermalized descent Free Flight style thats variable slight limited full Compensating up elevator varies amount spoiler applied model can hold increasing nose-up attitude augment sink desired point STOL descent chooses Its possible fully open spoilers land ing pattern power downwind arriv ing 50 ft high just 100 ft short runway go idle STOL down head runwayor exit thermals approach 600 flight path high altitude anywhere easily hit spot spoiler action limited enough allow final flare safety tech niques fully described Winters arti cle Spoilers Power Febru ary 1986 Model Aviation flying habits MK II dont re quire special description can build youll know what MK II excels close-in maneuvers allowing nervous pilot enough reaction time prevent ships getting ahead him Due airfoil type angular rig ging spoilers appropriate gentlest headwind either model will fly ground cushion extremely low power pilot holds up elevator Winter claims has walked quickly beside MK pilot slows up too much final close ground both ships can stagger around like drunken sail ors until aileron response lost common VEND MOUNTSOn. THE VIBRATION KILLERRubber ft Engine Power Free Flight Display Fail fuel poot In. axes jaolaton 25 00 engine..eo .Control Line Electric Power RIC Airplanes File aCtually tiloWalt angIna'"Our new illustrated 32 page tabloid size catalog mounts Typical oibationtduction TOT, tae85%Tt 01 OOneieteOfUS ft Canada *100 Foreigli $300 moultIS salute four POints 0002ndt'l nn Valley Hobby center washers tubing inStruCtIOnS Sand Sf200 Otrena non Order837-A W Main St Lanadale PA 19448 000 kit GSA PRODUCTS PC 800 3602$ SARASOTA FL 34233 StOOar 3684770 3774252 FL residnts add 72% SaleS faa IRFO5MATIOR sand SASS THE KOMBAT 40 - GREAT R/C SPORT AFPLANE AND WITH SO LITTLE TIME AND MONEY INVESTED YOU CAN REALLY HAVE BALL iTS FULLY AEROBATIC AND EXTREPRELY DURABLE CONSTRUCTED OF ALUtvtIUM AND RUBBERIZED PLASTIC YOU PROVDE THE RADIO AND ENGINE WE SUPPLY EVERYTHING ELSE NO EXTRAS TO BUY 25 ENGINE MAKES GREAT ADVANCED TRAINER SPECIAL INTRODUCTORY OFFER 5 POSTPAID LIST $8995 1880 PINEVIEW MANDEVILLE LA 70448 November 1990 197 620 CRANDALL-LANESVILLE RD CORYDON INDIANA 471 LARGE SELECTION OF REMOTE CONTROL MODEL AIRPLANES AND ACCESSORIES FOR THE PROFESSIONAL A-J US TO JIG AMBROID ARCO RUBBER BANDS BRIDI DA VEYS SYSTEMS CHAMPION CO yE RITE DEVCON SIG SONIC-TRONICS STERLING SULLIVAN TOP FLITE YS ENGINES ZINGER PROPS FK art fiberglass fuSel MADE IN USA PHONE ORDERS 504 626-7840 1-8002647840 SATISFACTION GUARANTEED FLYABLE IN ONE HOUR 1EdiTT FOR ORDERS ONLYJLr7TY 1 -8OO633-7556CODs IN ALABAMA 3473525 COLLECTWELCOME TOP QUALITY FUEL FOR EXPERT OR BEGINNER NO RE-CLAIMED ALCOHOL O METHANE ONLY IS USED Designed tested give top performance both 2 cycle 4-cycle engines ringed Except engines requiring low lubricant content CONTAINS NEW TRULY SPACE AGE ADDITIVE ha deve oped nan outer space vacuum new additive attaches internal metal parts ot engine will reduce nc much 80 reduces heat wear absolute minimum WE HAVE 3 LUBRICANT BLENDS ALL SYNTHETIC OR SYNTHETIC BLEND CASTOR lOur castor new h gh Pu y much c eaner burning castor ALL OUR FUELS CONTAIN ANTIFOAMERS PREVENTERS WEAR ADDITIVES tuel developed priced nd v dus c ub d ect sales market dealer inquiries invited Ord gailon up Mis OK i 4 gailon cases up ALL FUEL EXCEPT 54 GALLON DRUMS SHIPPED FREIGHT PRE-PAID Oniy Coniinentsi USA fTo 3 GalI 23051jTo 63 GaiITO 127 Gal/ Up / Freight Collects 1 Gal4 Gal 24 Gat~64 Gal I28 Gait 54 Gal Drum 50/ 1095 0065057518500 12/1495. 95090085077528000 25%1995 1450 400 1350 1275 47500 50% 2695 22 50 2200 2075 78000 Manufactured MACH-7 PO Box 1201 Enterprise Alabama 36330 condition can landed rud-touch down withtn foot white dot der reassuring know rudder willMiracle Landing/Jollythe runway camera zooming hold heading goof go-roundContinued page 104 tight realism youre sort modeler must Mile Square wasnt closed way have fireworks build standard Stik alibbed walked away epoxyssince flying off adjacent runway piped 60 its realistic enjoyment thatnot holding up Once lower stan-under tightly controlled conditions Sport want either Krackerjacs isdards Krylon model will last for-flying continued active runway pleasant own flyeverthere no lack interested helpers paradox proved true theEach 12 flights last day Epilogue Evans shipped MK IIday 737 made see dif-picture perfect Kent would light fires Winter stab detached itficult shots wed asked like fly-and plane would accelerate lift off taped note Leave off fliesing over edge runway three feetfly Steve Korney tracked 737 over better Winters comment Ifabove ground came off hitch80 mph gear-down over 90 mph gearEvans isnt spoofing would have used ai-Imagine foam glass Krylonup literally stopped traffic nearby lerons elevons reflexed upwardscooting along 80-mph-plus over thestreets drivers spotted what appeared ral control CG atsame ground track time after time Thenbe stricken airliner landing Mile Square 20% Enough alreadythere landings model Continued page 200 PRODUCTS Complete Line Exhaust Systems Tuned Muffled Tuned Pipes Headers uri Mufflers Expansion Mufflers copter Ball Mufflers ialized Exhaust Systems Unsupassed Workmanshin B Paiformance 198 Model Aviation TulnkflvCosnWed Shotioq 1/4 Scale Kits $12995 Epoxy/Glass/Foam Construction Drawings Data Formula 120 Pylon Sport Standoff ScaleKit Price ping Credit Cards WelcomedOhio Residents Add 7%
Edition: Model Aviation - 1990/11
Page Numbers: 83, 84, 85, 86, 87, 88, 196, 197, 198
Krackerjac Mk Mk II favorite oddcouple design team backthis time two-for-one like options build RC sport plane/ trainer combo Mark soars delightfully its higher performance sibling gets excellent marks hot-dogging U Bill Winter Bill Evans VOICE OFFSTAGE go again opposite schools design coau thors have managed second last presumes unlikely collaboration West Coaster Evans loves straight-up 140 0-plus flybys known philoso phy horizontal tails tantamount buggy-whip technology East Coaster pre historic old-timer Bill Winter go-slow airplane watcher thinks straight-up folks harbor hidden rocketry complexes Still found middle ground pro duced Krackerjac MK II Asked Evans would stoop build ing conservative cabin job conspic uous stabilizer Winter would say Whats nice guy like Bill Evans doing place like two collaborated Simitar Slow Motion published January 1987 issue Model Aviation docile flying wing almost easy fly Eaglet time Winters responsiveness Simitar proj ect flabbergasted Evans Winter ever did impose certain conditions First model soarso speed range set 15 80 mph plane fully controllable either rudder aileronsso equipped elevons Because specifications fuselage behind bobtail trailing edge termination extended some eight inches rudder post Since Winter also demanded extended pe riods hands-off flying modest dihedral added Indeed Slow Motion would 720s hands-off initial tap aileron stick save weight ship Krackerjac Mark pictured before its first flight flown Bill Winter couple years before being modified installing spoilers 6-ft-span 40-powered ship has wings stabilizer open-frame construction airfoil thin flat bottomed up main spar has long Phillips entry model has over 6 sq ft area under 19-ozIsq-ft loading will soar easily weak thermals airplane takes off climbs out 1A throttle will consecutive outside loops ttle fly about verted % throttle Bill added spoilers landings could easily made short flying fields Mk Bill Winters newest version Krackerjac seen doing what Bill likes besta slow flyby low altitude low throttle Model can equipped spoilers much like Thermal Soarers help control landings lightly loaded ship Tom Schmitt photo November 1990 83 little headwind model will tly ground cushion extremely low throttle Win ter claims times has able walk quickly beside model still airborne Mk floating its wheels just above grass Tom Schmitt photo tail-dragger protect old man Evans added foot span Aerobatic capability must K&B Veco 19 maximum power after adding second foot span bringing model six feet using 05 15 power performance essentially un changed did Evans Winter join gether second time Krackerjac Winter In 1960 good systems fullhouse control around about five years us could afford single-channel escapement airplanes Lacking elevator control designs addicted ballooning turns wind fly-aways commonplace original 54-in model called K rudder-only control quick-blip high/low throttle Max 15 ended non sense plane published Air Trails kitted Jetco Incidentally throttles time used exhaust stack re strictor coupled butterfly ven turi thin airfoil long Phillips en try secret models controlla bility original handled like multi llent penetration facility per fect touch-and-goes RCs over 40-year period three continue built Antique RC Special published 1948 early-60s Krackerjac reed-systems low-wing Rookie first published Model Airplane News early Sixties later some what modified publication Model Builder Other modelers have frequently im proved upon designs continue Several years ago obtained 6-ft ver sion Krackerjac 40 power plans service built model dozen test flights magazine ex pressed desire publish major manufacturer asked about kit mag wanted perfect pictures unfortu nately Id already marred covering stall spoilers wing efficient 6 sq ft 7A lb gross weight like Glider difficult get ground 300-ft strip Krackerjac soared ease dis covered day turning cross wind leg sixth flight noted no loss altitude did 360 ended up clouds Equipped 40 model demon strated considerable prowess took off climbed one-third throttle could fly inverted respond steering half throttle performed consecutive outside loops half throttle one-third down el evator Yet magazine staff thought plane should have 120 Hard believe told kit company opinion Krackerjac wasnt mainstream hence its best interests aircraft eventually given Doug Pratt converted K&B 40 to Enya four-stroke 46 Pratt has flown three seasons happened mention Bill Evans adding could get clean photos thought should published Evans Curiosity killed cat though find horizontal tails useless appendages Winters strange short-coupled cabin its big stab bottom odd appeal could build onemy way youll seeand fly within week Winter sent print Finding untried modification using semisymmetri cal airfoil 60 power phoned him ask Which would like build said might check out never-built aerobatic version Winter uses lots sticks Im always hurry So simplified fuse went foam balsa-skinned wing stab isnt neutrally stable prefer Winter wont give up measure hands-off control otherwise flies great Winter able join California watching pleased expressions flew per formance version treasured moments Ill never live down project has tail Everybody fly visits shop ribs unmercifully too much shipped model Winter year later Alas reports UPS stress tested wing found wanting Winter So now two airplanes different performance envelope working plan original good new pictures Evans Attempts revise original print tracer ran stone wall project sat 15 months Evans Dont ever get mixed up hair-splitting old-timers Theyll drive up wall kept asking Winter Whats problem Air Force project overruns delays would have provoked Congress hed draw wed done week Finally badgered him drawing incorporating sup plementary drawings decided show cross-options stuff crammed plans could come up least four differ ent ships Maybe should have sold National Geographic Surprise editor gave him green light two 40 x 52-in sheets proposed Winter designate original Mark call Mark II added Buddy East Coast now its own Winter Which build what ex pect Marks Design objectives MK easy piloting rather like 40-powered Senior Falcon Sig Kadet Goldberg Ea gle ability groove well maneuvers better average aerobatics enough reaction time prevent airplanes getting ahead average pi lot slow landings automatic takeoff though its tail-dragger ability ride weak general lift thermal soar Fly 84 Model Aviation close-up shot shows some details Mk built-up wing spoilers shown partially deployed control servos visible under transparent wing covering Steve Kaluf demonstrates short landing tech niques using spoilers plane will land observed attitude reserve flare can abort spoilers deployed Specs spoilers Size opening location etc shown plans tailored safe flight envelope ing techniques discussed end article low wing loading 19 ozI sq ft low drag result consistent ma chine sustains open maneuvers rela tively low power hands-off stability makes relaxed flying What about bigger engine Except improved vertical maneuvers brings added power self-defeating case 60 two-stroke limit youll find yourself doing aerobatics half power potent four-stroke such Enya 60 plenty Watch center-of-gravity such heavy engine An Enya 46 fourstroke does aerobatic maneuvers except advanced such knife-edge flight careful building can achieve gross weight seven pounds Mine turned out 7 lb spoilers two extra servos Some may come 8 lb because some always Dont load up paint Since ship can soar its lightly loaded large wing being equiv alent lower loading smaller wing has significantly higher Reynolds number long low approaches neces saryand critical small field obstacles beneath approach path may overshoot 300-ft strip model too high and/or too fast may wish consider spoiler option Spoilers allow make higher approaches land within first half strip Used front-hinge did create another fun mode flying described later MK Ls open-frame wing thin well large area heavy-handed pilot using oversized engine might overstress model example dive followed abrupt pullout overapplica tion up Evans MK H Winter specified airfoil incidence power 60 en gine version faster far Mark Its also spectacular groovy its closer being neutrally stable MK airplane still safe fly hands-off Winter said wanted two degrees dihedral own insur ance fuselage sides bottom shaped framed prepared ammbly ply gear plate place corner pieces will rounded later cross pIeces glued untrimmed bottom sheet grain running lengthwise side crosspieces trimmed exactly fit Note fishtail butt loint side sheeting above stabilizer saddle docile aircraft rather different fast neutrally stable machines Im used Still found nice fly wrung out Winter California handed controls over him Its measure planes easy handling low-speed abilities cruising about half throttle Winter held light back-pressure steadily ex ecuting towering perfectly round beauti ful loopall touching controls including throttle downside model seemed rails Throughout flight OS 60 gave him power wanted Very slight back trim slower stooging around resulted prolonged slight climb 2A-/3 airfoil ship will climb one-third throttle 60 foam wing balsa skin weighs ex actly same Winters open-frame MK wingfor total model weight 7 lb model robust enough kind flying wing thicker thing increased performance MK H can flown safely anyone aileron experience Like MK will fly ruddernice know since very slow approach rudder last control fail normal aircraft As shown used two exterior-mounted small Futaba servos ailerons Ive used arrangement de signs because its simple speeds up building Winter shocked first saw quickly agreed good way go now has same setup low-wing Desperado Simitar deriva tive anhedral wing reports no trace exhaust dirt servos Winter plans details op tions shown consider before making final decision MK presented basically com plete optional spoilers shown Though spoilers bring interesting dimen sion flying theyre required Cross sections outlines shown MK II wing tail Two versions wing shown Mine slightly modi fied two-bolt-and-dowel attachment Evans wing has four bolts panel can seen Evans external bottommounted servos linkage mod ified panel shows optional standard sin gle-servo arrangement Two profiles show mounting saddle semisymmetri cal wing near side view shows Evans reshaped cabin top four-bolt attachment other shows wing modified dowel two bolts Also shown Evans simpler open nose can substituted com plicated semi-enclosed nose MK Construction Fuselage Two techniques used ease assembly First bottom lies flat workbench Evans used length A-in soft sheeting grain running length wise bottom glued A-in-sq bottom longerons crosspiec es sheeting isnt trimmed off until Left Using front cabin bulkhead ass hg builder glues sides bottom sheeting against bottom side pieces Right assembled fuselage minus top sheeting Note sheet laminations nose Excess bottom sheeting trimmed off point construction technique ensures perfect centerline alignment tail Both Mk Mk II fuselages built same manner November 1990 85 sides top place Drawing centerline bottom sheet ing allows precise positioning rud der post After top longerons side crosspieces have glued fin ished sides fitted top bottom sheeting against bottom longerons Erect main cabin bulkheads before bend ing sides inward aft rear cabin sta tion Second lengths sheet balsa dimen sions given plan laminated graduate inward nose ring avoids awkward bending sides area forward cabin nose rough shaped sanding board progressing coarse medium paper Note different airfoil options re quire different fuselage top rails proper seating semisymmetrical section matching saddle necessitates deeper top rail allow required cutout Likewise choice nose wing op tions influences selection hold-down method consequently number location tapped hold-down blocks dow els etc Tail surfaces selection tail type de termines shape saddle bottom-mounted stabilizer MK built-up stab has cross section basically like two triangles set base base spar position Dress cross section precise contour sanding board sloping edges match shal low triangular shapes beveling edges flat spars Hold sanding Bill Evans showing off trademarks small external aileron servos Bill Winter impressed simplicity now has several models board steadily against edge spar youre working Finish moving board about gradually taking down mate rial along span rather anchoring spot Bolt-on stab mounting recommended easy transportation compact car either tail option epoxied place cer tain remove covering wood-towood joints includes covering laps around bottom saddle assembling vertical surfaces caution trial fit rudder tiller arm allowing sufficient space swing freely prevent metal-to-metal contacts thin neoprene tubing forced over tiller passed through rudder-mounted sheet metal bracket ac cepts tiller align independent finone isnt integral stabclamp thin straightedge hard straight flat piece wood cabin top aligned center marks Bend straightedge wood strip down centerline hole made tiller arm Draw guideline re move strip Evans cut MK II stab light weight foam two tapered halves butt joined centerline after being skinned A6 sheet balsa used own twosided Core Film tape attach skinning Its easy apply works well doesnt lift balsa skin Evans also used own X-Hingeslong sewn hinge strips cut length ironed close hinge gap accept MonoKote well Note leading edge spar glued foam slabs Use yellow glue similar adhesive Sand edges matching contour first achieving flat sloped surface sheeting will glued later rounding off full leading edge Evans glued stab place pre fer bolt yours sure reinforce bolt holes between top bottom sheet ing adequate quantity balsa stalled grain runs vertically Bolts will crush unsupported foam must done prior skinning Adhesives view differences ma terials between two Krackerjac ver sions few notes order wide variety glues can used balsato-balsa joints both authors used Hot Stuff instant well slow-setting because shortens building time Winter finds 3M spray-can contact cement suitable lami nating nose block sheets Epoxy used firewalls wing joiners though Win ter used white glue joiners openframe wing Both Evans Winter used two-sided Core Film skinning Contact cement may substituted make sure its com patible foam 3M spray can vari ety helps job go quickly White glue used attach balsa edge pieces foam cores Winter pro tects inside surfaces nose cavity 86 Model Aviation Above Bill Evans making slow flyby Mk ii Krackerjac crystal-clear air Bishop CA high-performance version equipped OS 60 two-stroke has ailerons rigged fiapperons Look closely youll notice flaps partially deployed Below closer look Mk ii fiapperons clearly visible model has balsaskinned foam core wing stabilizer no spoilers Winter %-1A French-curve airfoil two coats thinned epoxy Landing gear Any standard metal gear satisfactory Halico gear appropri ate size 7A-lb plane bit flimsy anything good landing original Great Planes gear wider tougher Both legs gear bent slight toe-in angle Toe-in eliminates erratic takeoff runs thereby reducing corrections Planes pronounced torque swings will behave bet ter perfectly toe-in No two degrees both toe-in castor recommended standard gear can twisted angle large bench vise Attach gear either two A-in ny lon bolts fitted blind nuts four self-tapping screws nylon bolts will shear semicrash landing broken rem nants can removed heating tip screwdriver Klett plastic gear appeared af ter design produced medium size recommended MK wing open-frame wing can built spoilers men tioned Construction techniques will fa miliar builder experience undertake project nature long Phillips entry airfoil curve leading edge near spar position bottom has characteristics close semisymmetrical section flat portion aft spars makes easy assemble bench Though spacing blocks eliminated its advisable block up leading edge ensure align ment Use standard glue epoxy tach joiners spoilers used note spar webs area front spars clear spoiler horn plans show sizes align ment bellcranks linkage spoiler servo have different servo arm travel indicated plan compensate appropriate holes dont change horn spacing spoiler Washout MK wing achieved bottom-sanding board tip area indicated plan MK II wing Evans built wing foam skinned A6 balsa sheeting airfoil approximate A-2A semisymmetrical section set less incidence MK wing produces less angular difference between wing stab improves aer obatics higher speeds Again Core Film tape X-Hinges used Other hinges may substi tuted made Robart example strong easy usesimply bore holes insert hinges epoxy Since ailerons rather thick fash ion lightest possible balsa Construction differs somewhat used foam stab leading edge built two pieces inner pieces glued flat edge foam sanded before skinning aileron spar re ceives same treatment skinning ex tends over edges After skinning leading edge proper glued front wing Its depth equal inner lead ing edge plus thickness top bottom skins Evans joiner though built A-in ply shallower shown Since UPS performed ultimate stress test changed full-depth joiner shown cut depth foam wing /6 ply slot full-depth joiner easier cut saw tapered por tion joiner will leave gap slot close-up shot Mk Iis tail feathers shows short externai cievis rod runs devises middle hoies arge horns boit visible behind rud der horn retains tail wheei tiiler arm plans show bolt-on arrangement stabilizer its epoxied place plane can filled epoxied scrap foam microballoons mixed epoxy installing two outboard servos wing bottom Evans threaded servo leads through short paper tube buried foam wing before skinning An optional standard single-servo installa tion shown requires servo cavity wood mounting pieces built after skinning panel joining completed November 1990 87 Bill Winter didnt have force smile photo just completed tower ing perfectly round loop half throttle holding gentle stick pressure corrections first flight Evans high-performance Mk ii business end Evans Mk Ii Its OS 60 swinging 11 x 7 Zinger prop simple open-nose configuration shown option plans profile less deep Winters Mk version windshield carved block balsa Vertical-grain blocks un der two wing hold-down bolts prevent crushing foam wing skin Note ex haust diverter made copper plumbing elbow retained common hose clamp Block up panel turn proper dihedral aligning wing root edge workbench sanding board can used smooth matching root sections Some foam removed ac commodate smaller front rear join ers Trial fit panels joiners until fit perfect Before permanently inserting joiners work epoxy evenly slots smooth evenly over joiners Cover center joints M-oz glass cloth Attach cloth epoxy rubbing out excess outer edges wiping off residue wing tips sloped sanding board Make plywood jig piece check ing proper angle tips made soft sheeting overlap top bottom skin leave excess Block sand match wing top bottom Covering Though iron-on coverings easy use recommend textured mate rial MK companies sell dif ferent varieties often can painted MK used silk/rayon applied buty rate fuselage finished two coats K&B epoxy paint wings tail however covered Super Mono Kote Though excellent popular prod uct turned out unsuitable large-area open-frame wing ship size weight landing made considerable vertical impact during spoiler experiments MK dead weight wings flexed down structural damage split covering chordwise edge edge Covering sheeted fuselage A-oz glass cloth attached K&B satin brush ing epoxy provides strength good finish imperviousness raw fuel glass cloth brushes out flat pulling follows curves corners After allow ing stand overnight can sanded beautifully fine-grade paper given second coat K&B epoxy col ored paint wont leave trace brush mark single coat works well two sufficient Other material re quired open stab wing Super MonoKote worked well MK II its wing being solid rather openframe construction Evans loves effect orange accented dark blue striping MK has red fuselage orange wings stab silver vertical red-orange combination happenstance Winter 25-ft roll orange hand Yellow would make less fiery contrast red background Flying Anyone building mod els already knows flyor should notes follow intended famil iarize handling characteristics Winters Evans modelsa preflight handoff speak primary focus MK Since MK intended fly wing power spectacular vertical maneuvers high-rate rolls expected craft wasnt designed per form knife-edge categoryresponses realistic stick pressures pilot MK delivers some nice performance indeed Pilots full-size air planes will sense familiar feedback fact flying model rather like being cockpit aircraft does would expect Because flies wing Mark will surprise certain modes course vertical performance would improve 60 engine much power would disadvantage other re spects bigger engine would have throttled back considerably time using high power climb ma neuvers full power heavy down trim would required due lift available would need either fly backstick remove considerable down trim dur ing approaches landings K&B 40 MK lifts off one-third power out pilots touching elevator theres no need two-thirds throttle point Incidentally 10 x 6 pro peller usual choice 11 x 5 wood prop better matched models aero batics proper center-of-gravity CG loca tion flat-bottomed airfoil section 25% chord Though pilots ac customed trimming 33% requires down trim cruising heavier control deflections inverted outside loops forward position gives solid feeling better penetration less bouncing around wind light wing load ings ride bumpily wind Approaches positive groove good test appropriateness CG location aerobatics perform outside loop constant elevator power ship buttonhooksthat tightens up during last quarter maneuver straightens back level flight lower its original altitudethis means its too nose-heavy Because model both short-coupled tail-dragger full up elevator recom mended slow taxiing grassespe cially grass long ragged begin takeoff advance throttle slowly smoothlynever abruptlywhile continu ing hold up elevator short distance typically 10 ft Actually lower power Continued page 196 88 Model Aviation Bill Evans baisa4kinned foam-core Mk ii wings root left has yet slotted joiner pians shows fuii-depth joiner requiring presiotting foam Evens inserts deep joiner through bottom slot including bottom skin cutout wing tip right msde soft sheet balsa cut oversize sanded flush top bottom sheeting foam-core stabilizer halves Evans Mk ii have skinned balsa sheeting ready joined center epoxy tips made sheet balsa --- * fl5 E Main Northvlfle Ml 481 67 Special Fast Turnaround Now Available CALL Frequency Conversion $4000 Includes Crystals Certification Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royai Tower HobbiesWorld Engines Spectrum Ana lyzers Cali brated Test struments Large Inventory R/C Parts Crystals Self I Addressed Envelope Ill Fly What Fix LeI ZAP UNIVERSITY COLLEGE OF GLUE KNOWLEDGE turn use small medical syringe meter fuel engine Cardinal will fly out sight full tank measuring fuel important Limit first test flights short engine runs five seconds stretching long practical ie long care run af ter model once things look safe Normally start priming engine hooking up battery Once prime fuel left tank run out feed measured amount check wind direc tion start engine needle valve preset produce slow run once its running its time launch its gusty day Cardinal probably ready its trim dihedral model will handle fair amount wind Make sure shes launched directly wind just slightly off right Sport flying should always much fun Krackerjac/Wi nter-Evans Continued page 90 used begin roll followed smooth steady advancing throt tle pilot wont need bold up take off allowing roll develop bit before going higher power increase airspeed point rudder has good bite steering tail-dragger steering control low speeds derives tail wheel much rud der quick surge power allowed lift tail instantly airplane will lose steering power due loss tail wheel trac tion 5-mph headwind MK will climb quickly landing pattern height one-third power power expect airplane climb rapidly fly wing two degrees dihedral permits free flight hands-off stability yielding continu ous turns either aileron rudder out compromising wingovers etc stooging around wide turns can tight ened much desired touch up el evator nose wont drop return neutral roll out plane will nose-up invert MK raise nose slightly say 100 half roll al lows time feel matching down el evator before nose drops Powered 40 engine model will sustain invert ed maneuversincluding steering figure eights etcat two-thirds power one-half going down no two-thirds go ing down circumstances Three consecutive concentric outside loops can done flying off top half power one-third one-half go ing down power speed opens up outside increasing loadings up side possibly causing twisting out ship has area thats intended used Landing approaches long airUPS US Mail Federal Express OOD Mastercard Visa Acce ted YOU WONT GET STUNG ON OUR NEW STINGER ARF Fuselage Length 525 Wing Span 84 Rec Engine Size 12 42 cu inArea 1596 sq Flying Weight 14 lbs & upRadio Channels 4 Available favorite Hobby Dealer Replacement parts available Dealer distributor inquiries invited Write today information LANIER RC PO Box 458 ood GA 30566 532-6401 Made U S 196 Model Aviation LISTED FORACOMPLETh PLEASE SEND STAMPED SELF-AL mSAATL FOR YOUR BUSINESS _____I~\I plane shows surprising ability keep coming makes really good idle essen tial bigger lower pitched prop provides bit braking Because clean ap proach use stick pressure rather movements up elevator begin flareotherwise youll go out other side Slowly build up sink touchdown gradually increasing up pressure As mentioned ship soars easily has soared out turn cross wind adding power simply trim ming rudder flat wide circles Nor mally soaring MK done climb ing moderate glide altitude going notch above idle trimming rud der continuous flat circles lift cir cle tightens speed increases go idle shut off model becomes Glid er Dress circle diameters rudder trim locked model will bank steeply go automatic Its easy see spoilers added MK though theyre optional small front-hinged spoilers typi cal blade types designed put Sail plane ground will kill some lift minimum buildup drag MK spoilers set full-open posi tion 60% vertical effect requires steady compensation up elevator goaround aborted landing possible spoilers less full power Use proportional channel radio spoilers can opened degree de sired spoiler system designed produce dethermalized descent Free Flight style thats variable slight limited full Compensating up elevator varies amount spoiler applied model can hold increasing nose-up attitude augment sink desired point STOL descent chooses Its possible fully open spoilers land ing pattern power downwind arriv ing 50 ft high just 100 ft short runway go idle STOL down head runwayor exit thermals approach 600 flight path high altitude anywhere easily hit spot spoiler action limited enough allow final flare safety tech niques fully described Winters arti cle Spoilers Power Febru ary 1986 Model Aviation flying habits MK II dont re quire special description can build youll know what MK II excels close-in maneuvers allowing nervous pilot enough reaction time prevent ships getting ahead him Due airfoil type angular rig ging spoilers appropriate gentlest headwind either model will fly ground cushion extremely low power pilot holds up elevator Winter claims has walked quickly beside MK pilot slows up too much final close ground both ships can stagger around like drunken sail ors until aileron response lost common VEND MOUNTSOn. THE VIBRATION KILLERRubber ft Engine Power Free Flight Display Fail fuel poot In. axes jaolaton 25 00 engine..eo .Control Line Electric Power RIC Airplanes File aCtually tiloWalt angIna'"Our new illustrated 32 page tabloid size catalog mounts Typical oibationtduction TOT, tae85%Tt 01 OOneieteOfUS ft Canada *100 Foreigli $300 moultIS salute four POints 0002ndt'l nn Valley Hobby center washers tubing inStruCtIOnS Sand Sf200 Otrena non Order837-A W Main St Lanadale PA 19448 000 kit GSA PRODUCTS PC 800 3602$ SARASOTA FL 34233 StOOar 3684770 3774252 FL residnts add 72% SaleS faa IRFO5MATIOR sand SASS THE KOMBAT 40 - GREAT R/C SPORT AFPLANE AND WITH SO LITTLE TIME AND MONEY INVESTED YOU CAN REALLY HAVE BALL iTS FULLY AEROBATIC AND EXTREPRELY DURABLE CONSTRUCTED OF ALUtvtIUM AND RUBBERIZED PLASTIC YOU PROVDE THE RADIO AND ENGINE WE SUPPLY EVERYTHING ELSE NO EXTRAS TO BUY 25 ENGINE MAKES GREAT ADVANCED TRAINER SPECIAL INTRODUCTORY OFFER 5 POSTPAID LIST $8995 1880 PINEVIEW MANDEVILLE LA 70448 November 1990 197 620 CRANDALL-LANESVILLE RD CORYDON INDIANA 471 LARGE SELECTION OF REMOTE CONTROL MODEL AIRPLANES AND ACCESSORIES FOR THE PROFESSIONAL A-J US TO JIG AMBROID ARCO RUBBER BANDS BRIDI DA VEYS SYSTEMS CHAMPION CO yE RITE DEVCON SIG SONIC-TRONICS STERLING SULLIVAN TOP FLITE YS ENGINES ZINGER PROPS FK art fiberglass fuSel MADE IN USA PHONE ORDERS 504 626-7840 1-8002647840 SATISFACTION GUARANTEED FLYABLE IN ONE HOUR 1EdiTT FOR ORDERS ONLYJLr7TY 1 -8OO633-7556CODs IN ALABAMA 3473525 COLLECTWELCOME TOP QUALITY FUEL FOR EXPERT OR BEGINNER NO RE-CLAIMED ALCOHOL O METHANE ONLY IS USED Designed tested give top performance both 2 cycle 4-cycle engines ringed Except engines requiring low lubricant content CONTAINS NEW TRULY SPACE AGE ADDITIVE ha deve oped nan outer space vacuum new additive attaches internal metal parts ot engine will reduce nc much 80 reduces heat wear absolute minimum WE HAVE 3 LUBRICANT BLENDS ALL SYNTHETIC OR SYNTHETIC BLEND CASTOR lOur castor new h gh Pu y much c eaner burning castor ALL OUR FUELS CONTAIN ANTIFOAMERS PREVENTERS WEAR ADDITIVES tuel developed priced nd v dus c ub d ect sales market dealer inquiries invited Ord gailon up Mis OK i 4 gailon cases up ALL FUEL EXCEPT 54 GALLON DRUMS SHIPPED FREIGHT PRE-PAID Oniy Coniinentsi USA fTo 3 GalI 23051jTo 63 GaiITO 127 Gal/ Up / Freight Collects 1 Gal4 Gal 24 Gat~64 Gal I28 Gait 54 Gal Drum 50/ 1095 0065057518500 12/1495. 95090085077528000 25%1995 1450 400 1350 1275 47500 50% 2695 22 50 2200 2075 78000 Manufactured MACH-7 PO Box 1201 Enterprise Alabama 36330 condition can landed rud-touch down withtn foot white dot der reassuring know rudder willMiracle Landing/Jollythe runway camera zooming hold heading goof go-roundContinued page 104 tight realism youre sort modeler must Mile Square wasnt closed way have fireworks build standard Stik alibbed walked away epoxyssince flying off adjacent runway piped 60 its realistic enjoyment thatnot holding up Once lower stan-under tightly controlled conditions Sport want either Krackerjacs isdards Krylon model will last for-flying continued active runway pleasant own flyeverthere no lack interested helpers paradox proved true theEach 12 flights last day Epilogue Evans shipped MK IIday 737 made see dif-picture perfect Kent would light fires Winter stab detached itficult shots wed asked like fly-and plane would accelerate lift off taped note Leave off fliesing over edge runway three feetfly Steve Korney tracked 737 over better Winters comment Ifabove ground came off hitch80 mph gear-down over 90 mph gearEvans isnt spoofing would have used ai-Imagine foam glass Krylonup literally stopped traffic nearby lerons elevons reflexed upwardscooting along 80-mph-plus over thestreets drivers spotted what appeared ral control CG atsame ground track time after time Thenbe stricken airliner landing Mile Square 20% Enough alreadythere landings model Continued page 200 PRODUCTS Complete Line Exhaust Systems Tuned Muffled Tuned Pipes Headers uri Mufflers Expansion Mufflers copter Ball Mufflers ialized Exhaust Systems Unsupassed Workmanshin B Paiformance 198 Model Aviation TulnkflvCosnWed Shotioq 1/4 Scale Kits $12995 Epoxy/Glass/Foam Construction Drawings Data Formula 120 Pylon Sport Standoff ScaleKit Price ping Credit Cards WelcomedOhio Residents Add 7%
Edition: Model Aviation - 1990/11
Page Numbers: 83, 84, 85, 86, 87, 88, 196, 197, 198
Krackerjac Mk Mk II favorite oddcouple design team backthis time two-for-one like options build RC sport plane/ trainer combo Mark soars delightfully its higher performance sibling gets excellent marks hot-dogging U Bill Winter Bill Evans VOICE OFFSTAGE go again opposite schools design coau thors have managed second last presumes unlikely collaboration West Coaster Evans loves straight-up 140 0-plus flybys known philoso phy horizontal tails tantamount buggy-whip technology East Coaster pre historic old-timer Bill Winter go-slow airplane watcher thinks straight-up folks harbor hidden rocketry complexes Still found middle ground pro duced Krackerjac MK II Asked Evans would stoop build ing conservative cabin job conspic uous stabilizer Winter would say Whats nice guy like Bill Evans doing place like two collaborated Simitar Slow Motion published January 1987 issue Model Aviation docile flying wing almost easy fly Eaglet time Winters responsiveness Simitar proj ect flabbergasted Evans Winter ever did impose certain conditions First model soarso speed range set 15 80 mph plane fully controllable either rudder aileronsso equipped elevons Because specifications fuselage behind bobtail trailing edge termination extended some eight inches rudder post Since Winter also demanded extended pe riods hands-off flying modest dihedral added Indeed Slow Motion would 720s hands-off initial tap aileron stick save weight ship Krackerjac Mark pictured before its first flight flown Bill Winter couple years before being modified installing spoilers 6-ft-span 40-powered ship has wings stabilizer open-frame construction airfoil thin flat bottomed up main spar has long Phillips entry model has over 6 sq ft area under 19-ozIsq-ft loading will soar easily weak thermals airplane takes off climbs out 1A throttle will consecutive outside loops ttle fly about verted % throttle Bill added spoilers landings could easily made short flying fields Mk Bill Winters newest version Krackerjac seen doing what Bill likes besta slow flyby low altitude low throttle Model can equipped spoilers much like Thermal Soarers help control landings lightly loaded ship Tom Schmitt photo November 1990 83 little headwind model will tly ground cushion extremely low throttle Win ter claims times has able walk quickly beside model still airborne Mk floating its wheels just above grass Tom Schmitt photo tail-dragger protect old man Evans added foot span Aerobatic capability must K&B Veco 19 maximum power after adding second foot span bringing model six feet using 05 15 power performance essentially un changed did Evans Winter join gether second time Krackerjac Winter In 1960 good systems fullhouse control around about five years us could afford single-channel escapement airplanes Lacking elevator control designs addicted ballooning turns wind fly-aways commonplace original 54-in model called K rudder-only control quick-blip high/low throttle Max 15 ended non sense plane published Air Trails kitted Jetco Incidentally throttles time used exhaust stack re strictor coupled butterfly ven turi thin airfoil long Phillips en try secret models controlla bility original handled like multi llent penetration facility per fect touch-and-goes RCs over 40-year period three continue built Antique RC Special published 1948 early-60s Krackerjac reed-systems low-wing Rookie first published Model Airplane News early Sixties later some what modified publication Model Builder Other modelers have frequently im proved upon designs continue Several years ago obtained 6-ft ver sion Krackerjac 40 power plans service built model dozen test flights magazine ex pressed desire publish major manufacturer asked about kit mag wanted perfect pictures unfortu nately Id already marred covering stall spoilers wing efficient 6 sq ft 7A lb gross weight like Glider difficult get ground 300-ft strip Krackerjac soared ease dis covered day turning cross wind leg sixth flight noted no loss altitude did 360 ended up clouds Equipped 40 model demon strated considerable prowess took off climbed one-third throttle could fly inverted respond steering half throttle performed consecutive outside loops half throttle one-third down el evator Yet magazine staff thought plane should have 120 Hard believe told kit company opinion Krackerjac wasnt mainstream hence its best interests aircraft eventually given Doug Pratt converted K&B 40 to Enya four-stroke 46 Pratt has flown three seasons happened mention Bill Evans adding could get clean photos thought should published Evans Curiosity killed cat though find horizontal tails useless appendages Winters strange short-coupled cabin its big stab bottom odd appeal could build onemy way youll seeand fly within week Winter sent print Finding untried modification using semisymmetri cal airfoil 60 power phoned him ask Which would like build said might check out never-built aerobatic version Winter uses lots sticks Im always hurry So simplified fuse went foam balsa-skinned wing stab isnt neutrally stable prefer Winter wont give up measure hands-off control otherwise flies great Winter able join California watching pleased expressions flew per formance version treasured moments Ill never live down project has tail Everybody fly visits shop ribs unmercifully too much shipped model Winter year later Alas reports UPS stress tested wing found wanting Winter So now two airplanes different performance envelope working plan original good new pictures Evans Attempts revise original print tracer ran stone wall project sat 15 months Evans Dont ever get mixed up hair-splitting old-timers Theyll drive up wall kept asking Winter Whats problem Air Force project overruns delays would have provoked Congress hed draw wed done week Finally badgered him drawing incorporating sup plementary drawings decided show cross-options stuff crammed plans could come up least four differ ent ships Maybe should have sold National Geographic Surprise editor gave him green light two 40 x 52-in sheets proposed Winter designate original Mark call Mark II added Buddy East Coast now its own Winter Which build what ex pect Marks Design objectives MK easy piloting rather like 40-powered Senior Falcon Sig Kadet Goldberg Ea gle ability groove well maneuvers better average aerobatics enough reaction time prevent airplanes getting ahead average pi lot slow landings automatic takeoff though its tail-dragger ability ride weak general lift thermal soar Fly 84 Model Aviation close-up shot shows some details Mk built-up wing spoilers shown partially deployed control servos visible under transparent wing covering Steve Kaluf demonstrates short landing tech niques using spoilers plane will land observed attitude reserve flare can abort spoilers deployed Specs spoilers Size opening location etc shown plans tailored safe flight envelope ing techniques discussed end article low wing loading 19 ozI sq ft low drag result consistent ma chine sustains open maneuvers rela tively low power hands-off stability makes relaxed flying What about bigger engine Except improved vertical maneuvers brings added power self-defeating case 60 two-stroke limit youll find yourself doing aerobatics half power potent four-stroke such Enya 60 plenty Watch center-of-gravity such heavy engine An Enya 46 fourstroke does aerobatic maneuvers except advanced such knife-edge flight careful building can achieve gross weight seven pounds Mine turned out 7 lb spoilers two extra servos Some may come 8 lb because some always Dont load up paint Since ship can soar its lightly loaded large wing being equiv alent lower loading smaller wing has significantly higher Reynolds number long low approaches neces saryand critical small field obstacles beneath approach path may overshoot 300-ft strip model too high and/or too fast may wish consider spoiler option Spoilers allow make higher approaches land within first half strip Used front-hinge did create another fun mode flying described later MK Ls open-frame wing thin well large area heavy-handed pilot using oversized engine might overstress model example dive followed abrupt pullout overapplica tion up Evans MK H Winter specified airfoil incidence power 60 en gine version faster far Mark Its also spectacular groovy its closer being neutrally stable MK airplane still safe fly hands-off Winter said wanted two degrees dihedral own insur ance fuselage sides bottom shaped framed prepared ammbly ply gear plate place corner pieces will rounded later cross pIeces glued untrimmed bottom sheet grain running lengthwise side crosspieces trimmed exactly fit Note fishtail butt loint side sheeting above stabilizer saddle docile aircraft rather different fast neutrally stable machines Im used Still found nice fly wrung out Winter California handed controls over him Its measure planes easy handling low-speed abilities cruising about half throttle Winter held light back-pressure steadily ex ecuting towering perfectly round beauti ful loopall touching controls including throttle downside model seemed rails Throughout flight OS 60 gave him power wanted Very slight back trim slower stooging around resulted prolonged slight climb 2A-/3 airfoil ship will climb one-third throttle 60 foam wing balsa skin weighs ex actly same Winters open-frame MK wingfor total model weight 7 lb model robust enough kind flying wing thicker thing increased performance MK H can flown safely anyone aileron experience Like MK will fly ruddernice know since very slow approach rudder last control fail normal aircraft As shown used two exterior-mounted small Futaba servos ailerons Ive used arrangement de signs because its simple speeds up building Winter shocked first saw quickly agreed good way go now has same setup low-wing Desperado Simitar deriva tive anhedral wing reports no trace exhaust dirt servos Winter plans details op tions shown consider before making final decision MK presented basically com plete optional spoilers shown Though spoilers bring interesting dimen sion flying theyre required Cross sections outlines shown MK II wing tail Two versions wing shown Mine slightly modi fied two-bolt-and-dowel attachment Evans wing has four bolts panel can seen Evans external bottommounted servos linkage mod ified panel shows optional standard sin gle-servo arrangement Two profiles show mounting saddle semisymmetri cal wing near side view shows Evans reshaped cabin top four-bolt attachment other shows wing modified dowel two bolts Also shown Evans simpler open nose can substituted com plicated semi-enclosed nose MK Construction Fuselage Two techniques used ease assembly First bottom lies flat workbench Evans used length A-in soft sheeting grain running length wise bottom glued A-in-sq bottom longerons crosspiec es sheeting isnt trimmed off until Left Using front cabin bulkhead ass hg builder glues sides bottom sheeting against bottom side pieces Right assembled fuselage minus top sheeting Note sheet laminations nose Excess bottom sheeting trimmed off point construction technique ensures perfect centerline alignment tail Both Mk Mk II fuselages built same manner November 1990 85 sides top place Drawing centerline bottom sheet ing allows precise positioning rud der post After top longerons side crosspieces have glued fin ished sides fitted top bottom sheeting against bottom longerons Erect main cabin bulkheads before bend ing sides inward aft rear cabin sta tion Second lengths sheet balsa dimen sions given plan laminated graduate inward nose ring avoids awkward bending sides area forward cabin nose rough shaped sanding board progressing coarse medium paper Note different airfoil options re quire different fuselage top rails proper seating semisymmetrical section matching saddle necessitates deeper top rail allow required cutout Likewise choice nose wing op tions influences selection hold-down method consequently number location tapped hold-down blocks dow els etc Tail surfaces selection tail type de termines shape saddle bottom-mounted stabilizer MK built-up stab has cross section basically like two triangles set base base spar position Dress cross section precise contour sanding board sloping edges match shal low triangular shapes beveling edges flat spars Hold sanding Bill Evans showing off trademarks small external aileron servos Bill Winter impressed simplicity now has several models board steadily against edge spar youre working Finish moving board about gradually taking down mate rial along span rather anchoring spot Bolt-on stab mounting recommended easy transportation compact car either tail option epoxied place cer tain remove covering wood-towood joints includes covering laps around bottom saddle assembling vertical surfaces caution trial fit rudder tiller arm allowing sufficient space swing freely prevent metal-to-metal contacts thin neoprene tubing forced over tiller passed through rudder-mounted sheet metal bracket ac cepts tiller align independent finone isnt integral stabclamp thin straightedge hard straight flat piece wood cabin top aligned center marks Bend straightedge wood strip down centerline hole made tiller arm Draw guideline re move strip Evans cut MK II stab light weight foam two tapered halves butt joined centerline after being skinned A6 sheet balsa used own twosided Core Film tape attach skinning Its easy apply works well doesnt lift balsa skin Evans also used own X-Hingeslong sewn hinge strips cut length ironed close hinge gap accept MonoKote well Note leading edge spar glued foam slabs Use yellow glue similar adhesive Sand edges matching contour first achieving flat sloped surface sheeting will glued later rounding off full leading edge Evans glued stab place pre fer bolt yours sure reinforce bolt holes between top bottom sheet ing adequate quantity balsa stalled grain runs vertically Bolts will crush unsupported foam must done prior skinning Adhesives view differences ma terials between two Krackerjac ver sions few notes order wide variety glues can used balsato-balsa joints both authors used Hot Stuff instant well slow-setting because shortens building time Winter finds 3M spray-can contact cement suitable lami nating nose block sheets Epoxy used firewalls wing joiners though Win ter used white glue joiners openframe wing Both Evans Winter used two-sided Core Film skinning Contact cement may substituted make sure its com patible foam 3M spray can vari ety helps job go quickly White glue used attach balsa edge pieces foam cores Winter pro tects inside surfaces nose cavity 86 Model Aviation Above Bill Evans making slow flyby Mk ii Krackerjac crystal-clear air Bishop CA high-performance version equipped OS 60 two-stroke has ailerons rigged fiapperons Look closely youll notice flaps partially deployed Below closer look Mk ii fiapperons clearly visible model has balsaskinned foam core wing stabilizer no spoilers Winter %-1A French-curve airfoil two coats thinned epoxy Landing gear Any standard metal gear satisfactory Halico gear appropri ate size 7A-lb plane bit flimsy anything good landing original Great Planes gear wider tougher Both legs gear bent slight toe-in angle Toe-in eliminates erratic takeoff runs thereby reducing corrections Planes pronounced torque swings will behave bet ter perfectly toe-in No two degrees both toe-in castor recommended standard gear can twisted angle large bench vise Attach gear either two A-in ny lon bolts fitted blind nuts four self-tapping screws nylon bolts will shear semicrash landing broken rem nants can removed heating tip screwdriver Klett plastic gear appeared af ter design produced medium size recommended MK wing open-frame wing can built spoilers men tioned Construction techniques will fa miliar builder experience undertake project nature long Phillips entry airfoil curve leading edge near spar position bottom has characteristics close semisymmetrical section flat portion aft spars makes easy assemble bench Though spacing blocks eliminated its advisable block up leading edge ensure align ment Use standard glue epoxy tach joiners spoilers used note spar webs area front spars clear spoiler horn plans show sizes align ment bellcranks linkage spoiler servo have different servo arm travel indicated plan compensate appropriate holes dont change horn spacing spoiler Washout MK wing achieved bottom-sanding board tip area indicated plan MK II wing Evans built wing foam skinned A6 balsa sheeting airfoil approximate A-2A semisymmetrical section set less incidence MK wing produces less angular difference between wing stab improves aer obatics higher speeds Again Core Film tape X-Hinges used Other hinges may substi tuted made Robart example strong easy usesimply bore holes insert hinges epoxy Since ailerons rather thick fash ion lightest possible balsa Construction differs somewhat used foam stab leading edge built two pieces inner pieces glued flat edge foam sanded before skinning aileron spar re ceives same treatment skinning ex tends over edges After skinning leading edge proper glued front wing Its depth equal inner lead ing edge plus thickness top bottom skins Evans joiner though built A-in ply shallower shown Since UPS performed ultimate stress test changed full-depth joiner shown cut depth foam wing /6 ply slot full-depth joiner easier cut saw tapered por tion joiner will leave gap slot close-up shot Mk Iis tail feathers shows short externai cievis rod runs devises middle hoies arge horns boit visible behind rud der horn retains tail wheei tiiler arm plans show bolt-on arrangement stabilizer its epoxied place plane can filled epoxied scrap foam microballoons mixed epoxy installing two outboard servos wing bottom Evans threaded servo leads through short paper tube buried foam wing before skinning An optional standard single-servo installa tion shown requires servo cavity wood mounting pieces built after skinning panel joining completed November 1990 87 Bill Winter didnt have force smile photo just completed tower ing perfectly round loop half throttle holding gentle stick pressure corrections first flight Evans high-performance Mk ii business end Evans Mk Ii Its OS 60 swinging 11 x 7 Zinger prop simple open-nose configuration shown option plans profile less deep Winters Mk version windshield carved block balsa Vertical-grain blocks un der two wing hold-down bolts prevent crushing foam wing skin Note ex haust diverter made copper plumbing elbow retained common hose clamp Block up panel turn proper dihedral aligning wing root edge workbench sanding board can used smooth matching root sections Some foam removed ac commodate smaller front rear join ers Trial fit panels joiners until fit perfect Before permanently inserting joiners work epoxy evenly slots smooth evenly over joiners Cover center joints M-oz glass cloth Attach cloth epoxy rubbing out excess outer edges wiping off residue wing tips sloped sanding board Make plywood jig piece check ing proper angle tips made soft sheeting overlap top bottom skin leave excess Block sand match wing top bottom Covering Though iron-on coverings easy use recommend textured mate rial MK companies sell dif ferent varieties often can painted MK used silk/rayon applied buty rate fuselage finished two coats K&B epoxy paint wings tail however covered Super Mono Kote Though excellent popular prod uct turned out unsuitable large-area open-frame wing ship size weight landing made considerable vertical impact during spoiler experiments MK dead weight wings flexed down structural damage split covering chordwise edge edge Covering sheeted fuselage A-oz glass cloth attached K&B satin brush ing epoxy provides strength good finish imperviousness raw fuel glass cloth brushes out flat pulling follows curves corners After allow ing stand overnight can sanded beautifully fine-grade paper given second coat K&B epoxy col ored paint wont leave trace brush mark single coat works well two sufficient Other material re quired open stab wing Super MonoKote worked well MK II its wing being solid rather openframe construction Evans loves effect orange accented dark blue striping MK has red fuselage orange wings stab silver vertical red-orange combination happenstance Winter 25-ft roll orange hand Yellow would make less fiery contrast red background Flying Anyone building mod els already knows flyor should notes follow intended famil iarize handling characteristics Winters Evans modelsa preflight handoff speak primary focus MK Since MK intended fly wing power spectacular vertical maneuvers high-rate rolls expected craft wasnt designed per form knife-edge categoryresponses realistic stick pressures pilot MK delivers some nice performance indeed Pilots full-size air planes will sense familiar feedback fact flying model rather like being cockpit aircraft does would expect Because flies wing Mark will surprise certain modes course vertical performance would improve 60 engine much power would disadvantage other re spects bigger engine would have throttled back considerably time using high power climb ma neuvers full power heavy down trim would required due lift available would need either fly backstick remove considerable down trim dur ing approaches landings K&B 40 MK lifts off one-third power out pilots touching elevator theres no need two-thirds throttle point Incidentally 10 x 6 pro peller usual choice 11 x 5 wood prop better matched models aero batics proper center-of-gravity CG loca tion flat-bottomed airfoil section 25% chord Though pilots ac customed trimming 33% requires down trim cruising heavier control deflections inverted outside loops forward position gives solid feeling better penetration less bouncing around wind light wing load ings ride bumpily wind Approaches positive groove good test appropriateness CG location aerobatics perform outside loop constant elevator power ship buttonhooksthat tightens up during last quarter maneuver straightens back level flight lower its original altitudethis means its too nose-heavy Because model both short-coupled tail-dragger full up elevator recom mended slow taxiing grassespe cially grass long ragged begin takeoff advance throttle slowly smoothlynever abruptlywhile continu ing hold up elevator short distance typically 10 ft Actually lower power Continued page 196 88 Model Aviation Bill Evans baisa4kinned foam-core Mk ii wings root left has yet slotted joiner pians shows fuii-depth joiner requiring presiotting foam Evens inserts deep joiner through bottom slot including bottom skin cutout wing tip right msde soft sheet balsa cut oversize sanded flush top bottom sheeting foam-core stabilizer halves Evans Mk ii have skinned balsa sheeting ready joined center epoxy tips made sheet balsa --- * fl5 E Main Northvlfle Ml 481 67 Special Fast Turnaround Now Available CALL Frequency Conversion $4000 Includes Crystals Certification Service Ace Cirrus EK Futaba Heathkit Hobbyshack JR KGL K-Line KO Propo Kraft KSE Logitrol Novak Royai Tower HobbiesWorld Engines Spectrum Ana lyzers Cali brated Test struments Large Inventory R/C Parts Crystals Self I Addressed Envelope Ill Fly What Fix LeI ZAP UNIVERSITY COLLEGE OF GLUE KNOWLEDGE turn use small medical syringe meter fuel engine Cardinal will fly out sight full tank measuring fuel important Limit first test flights short engine runs five seconds stretching long practical ie long care run af ter model once things look safe Normally start priming engine hooking up battery Once prime fuel left tank run out feed measured amount check wind direc tion start engine needle valve preset produce slow run once its running its time launch its gusty day Cardinal probably ready its trim dihedral model will handle fair amount wind Make sure shes launched directly wind just slightly off right Sport flying should always much fun Krackerjac/Wi nter-Evans Continued page 90 used begin roll followed smooth steady advancing throt tle pilot wont need bold up take off allowing roll develop bit before going higher power increase airspeed point rudder has good bite steering tail-dragger steering control low speeds derives tail wheel much rud der quick surge power allowed lift tail instantly airplane will lose steering power due loss tail wheel trac tion 5-mph headwind MK will climb quickly landing pattern height one-third power power expect airplane climb rapidly fly wing two degrees dihedral permits free flight hands-off stability yielding continu ous turns either aileron rudder out compromising wingovers etc stooging around wide turns can tight ened much desired touch up el evator nose wont drop return neutral roll out plane will nose-up invert MK raise nose slightly say 100 half roll al lows time feel matching down el evator before nose drops Powered 40 engine model will sustain invert ed maneuversincluding steering figure eights etcat two-thirds power one-half going down no two-thirds go ing down circumstances Three consecutive concentric outside loops can done flying off top half power one-third one-half go ing down power speed opens up outside increasing loadings up side possibly causing twisting out ship has area thats intended used Landing approaches long airUPS US Mail Federal Express OOD Mastercard Visa Acce ted YOU WONT GET STUNG ON OUR NEW STINGER ARF Fuselage Length 525 Wing Span 84 Rec Engine Size 12 42 cu inArea 1596 sq Flying Weight 14 lbs & upRadio Channels 4 Available favorite Hobby Dealer Replacement parts available Dealer distributor inquiries invited Write today information LANIER RC PO Box 458 ood GA 30566 532-6401 Made U S 196 Model Aviation LISTED FORACOMPLETh PLEASE SEND STAMPED SELF-AL mSAATL FOR YOUR BUSINESS _____I~\I plane shows surprising ability keep coming makes really good idle essen tial bigger lower pitched prop provides bit braking Because clean ap proach use stick pressure rather movements up elevator begin flareotherwise youll go out other side Slowly build up sink touchdown gradually increasing up pressure As mentioned ship soars easily has soared out turn cross wind adding power simply trim ming rudder flat wide circles Nor mally soaring MK done climb ing moderate glide altitude going notch above idle trimming rud der continuous flat circles lift cir cle tightens speed increases go idle shut off model becomes Glid er Dress circle diameters rudder trim locked model will bank steeply go automatic Its easy see spoilers added MK though theyre optional small front-hinged spoilers typi cal blade types designed put Sail plane ground will kill some lift minimum buildup drag MK spoilers set full-open posi tion 60% vertical effect requires steady compensation up elevator goaround aborted landing possible spoilers less full power Use proportional channel radio spoilers can opened degree de sired spoiler system designed produce dethermalized descent Free Flight style thats variable slight limited full Compensating up elevator varies amount spoiler applied model can hold increasing nose-up attitude augment sink desired point STOL descent chooses Its possible fully open spoilers land ing pattern power downwind arriv ing 50 ft high just 100 ft short runway go idle STOL down head runwayor exit thermals approach 600 flight path high altitude anywhere easily hit spot spoiler action limited enough allow final flare safety tech niques fully described Winters arti cle Spoilers Power Febru ary 1986 Model Aviation flying habits MK II dont re quire special description can build youll know what MK II excels close-in maneuvers allowing nervous pilot enough reaction time prevent ships getting ahead him Due airfoil type angular rig ging spoilers appropriate gentlest headwind either model will fly ground cushion extremely low power pilot holds up elevator Winter claims has walked quickly beside MK pilot slows up too much final close ground both ships can stagger around like drunken sail ors until aileron response lost common VEND MOUNTSOn. THE VIBRATION KILLERRubber ft Engine Power Free Flight Display Fail fuel poot In. axes jaolaton 25 00 engine..eo .Control Line Electric Power RIC Airplanes File aCtually tiloWalt angIna'"Our new illustrated 32 page tabloid size catalog mounts Typical oibationtduction TOT, tae85%Tt 01 OOneieteOfUS ft Canada *100 Foreigli $300 moultIS salute four POints 0002ndt'l nn Valley Hobby center washers tubing inStruCtIOnS Sand Sf200 Otrena non Order837-A W Main St Lanadale PA 19448 000 kit GSA PRODUCTS PC 800 3602$ SARASOTA FL 34233 StOOar 3684770 3774252 FL residnts add 72% SaleS faa IRFO5MATIOR sand SASS THE KOMBAT 40 - GREAT R/C SPORT AFPLANE AND WITH SO LITTLE TIME AND MONEY INVESTED YOU CAN REALLY HAVE BALL iTS FULLY AEROBATIC AND EXTREPRELY DURABLE CONSTRUCTED OF ALUtvtIUM AND RUBBERIZED PLASTIC YOU PROVDE THE RADIO AND ENGINE WE SUPPLY EVERYTHING ELSE NO EXTRAS TO BUY 25 ENGINE MAKES GREAT ADVANCED TRAINER SPECIAL INTRODUCTORY OFFER 5 POSTPAID LIST $8995 1880 PINEVIEW MANDEVILLE LA 70448 November 1990 197 620 CRANDALL-LANESVILLE RD CORYDON INDIANA 471 LARGE SELECTION OF REMOTE CONTROL MODEL AIRPLANES AND ACCESSORIES FOR THE PROFESSIONAL A-J US TO JIG AMBROID ARCO RUBBER BANDS BRIDI DA VEYS SYSTEMS CHAMPION CO yE RITE DEVCON SIG SONIC-TRONICS STERLING SULLIVAN TOP FLITE YS ENGINES ZINGER PROPS FK art fiberglass fuSel MADE IN USA PHONE ORDERS 504 626-7840 1-8002647840 SATISFACTION GUARANTEED FLYABLE IN ONE HOUR 1EdiTT FOR ORDERS ONLYJLr7TY 1 -8OO633-7556CODs IN ALABAMA 3473525 COLLECTWELCOME TOP QUALITY FUEL FOR EXPERT OR BEGINNER NO RE-CLAIMED ALCOHOL O METHANE ONLY IS USED Designed tested give top performance both 2 cycle 4-cycle engines ringed Except engines requiring low lubricant content CONTAINS NEW TRULY SPACE AGE ADDITIVE ha deve oped nan outer space vacuum new additive attaches internal metal parts ot engine will reduce nc much 80 reduces heat wear absolute minimum WE HAVE 3 LUBRICANT BLENDS ALL SYNTHETIC OR SYNTHETIC BLEND CASTOR lOur castor new h gh Pu y much c eaner burning castor ALL OUR FUELS CONTAIN ANTIFOAMERS PREVENTERS WEAR ADDITIVES tuel developed priced nd v dus c ub d ect sales market dealer inquiries invited Ord gailon up Mis OK i 4 gailon cases up ALL FUEL EXCEPT 54 GALLON DRUMS SHIPPED FREIGHT PRE-PAID Oniy Coniinentsi USA fTo 3 GalI 23051jTo 63 GaiITO 127 Gal/ Up / Freight Collects 1 Gal4 Gal 24 Gat~64 Gal I28 Gait 54 Gal Drum 50/ 1095 0065057518500 12/1495. 95090085077528000 25%1995 1450 400 1350 1275 47500 50% 2695 22 50 2200 2075 78000 Manufactured MACH-7 PO Box 1201 Enterprise Alabama 36330 condition can landed rud-touch down withtn foot white dot der reassuring know rudder willMiracle Landing/Jollythe runway camera zooming hold heading goof go-roundContinued page 104 tight realism youre sort modeler must Mile Square wasnt closed way have fireworks build standard Stik alibbed walked away epoxyssince flying off adjacent runway piped 60 its realistic enjoyment thatnot holding up Once lower stan-under tightly controlled conditions Sport want either Krackerjacs isdards Krylon model will last for-flying continued active runway pleasant own flyeverthere no lack interested helpers paradox proved true theEach 12 flights last day Epilogue Evans shipped MK IIday 737 made see dif-picture perfect Kent would light fires Winter stab detached itficult shots wed asked like fly-and plane would accelerate lift off taped note Leave off fliesing over edge runway three feetfly Steve Korney tracked 737 over better Winters comment Ifabove ground came off hitch80 mph gear-down over 90 mph gearEvans isnt spoofing would have used ai-Imagine foam glass Krylonup literally stopped traffic nearby lerons elevons reflexed upwardscooting along 80-mph-plus over thestreets drivers spotted what appeared ral control CG atsame ground track time after time Thenbe stricken airliner landing Mile Square 20% Enough alreadythere landings model Continued page 200 PRODUCTS Complete Line Exhaust Systems Tuned Muffled Tuned Pipes Headers uri Mufflers Expansion Mufflers copter Ball Mufflers ialized Exhaust Systems Unsupassed Workmanshin B Paiformance 198 Model Aviation TulnkflvCosnWed Shotioq 1/4 Scale Kits $12995 Epoxy/Glass/Foam Construction Drawings Data Formula 120 Pylon Sport Standoff ScaleKit Price ping Credit Cards WelcomedOhio Residents Add 7%