QUESTIONS often appear letters arrive mail box following letter addressed Model Aviation forwarded pub lisher may concern ve flying RC planes about 4/2 years now started Goldberg Eagle 63 Over time able perform various stunts such loops barrel rolls inverted flight touch-and-go etc recently purchased built Goldberg Sky Tiger problem cant get plane turn rudder left right use rudder plane does flat turn cant get plane bank unless use ailerons banldng try level plane out rudder acts its sideslipping Say Im banking right give left rudder roll out bank Instead plane rolling left level flight plane stays bank nose goes up doing sideways flat turn tends cause loss altitude cant life figure problem out control throws set according instructions now need some experi enced advice correcting matter plane flies well except fact cant use rudder turn letter signed John Fleming Vernon NY wrote letter John rea lized problem might shared number fliers hadnt written letters Model Aviation seeking help information Its easy understand lack rolling response rudder control input would cause pilot accustomed beginner-type aircraft think problem perhaps ginner aircraft intentionally have too much dihe dral wing Consequently rudder deflected airplane starts sideslip dihedral wing generates rolling moment airplane banks direction rudder deflected So pilot thinks rudder caused bank Well suppose rudder did cause bank couldnt have happened wing dihedral So have two ways bank airplane rudder ailerons Thats good Right really Using rudder bank air plane fine long dont want turn airplane beginner airplanes dont have ailerons perform missions very well rather abrupt turns performed using rudder/wing dihedral banldng mechanism its hard tell Lift Airplane Weight Angle Attack atrim Figure 1 Ron discusses stability trim answers questions about Pattern models seemingly inexplicable things sometimes figure porlrays unique wing angle tack s needed sustain airplane level unaccelerated flight particular airspeed turns arent being done using ailerons However reason using rudder bank airplane satisfactory beginners dont tend fly airplanes inverted per form maneuvers like knife-edge flight point rolls want progress flying advanced ma neuvers must have airplane does bank rudder deflected roll airplane knife-edge apply top rud der keep nose up dont want wing dihedral cause airplane roll So benchmarks airplane Pattern flying potential absence rolling ten dency rudder deflected goal learn fly Pattern ma neuvers can bank airplane rudder reduce wing dihedral until doesnt What did tell John Fleming Sky Tiger doing just what its supposed Dont change anything Another letter arrived Wil liam Roper Englewood CO wrote long Pitching Moment Angle Attack atrim E3 Figure 2 series curves illustrtates pitching moments generated stable air plane constant airspeed several different elevator deflections E1 E2 E2 order trim plane unique elevator deflection generating zero pitching moment trim angle attack attm found Figure 1 necessary Only elevator deflectIon satisfies things 42 Model Aviation Radio Cono Sport Aerobatics Ron Van Putte Ill Sleepy Oaks Rd Ft Walton Beach FL 32548 happens pros AMA President Don Lowe examines spot cov ering missing wing Phoe nix 9 sure makes funny sound de parts during flight letter suppositions questions Wont quote whole letter just part along responses William started out like What Im trying sort out straight level unaccelerated flight Pattern airplane slowly rolled 900 either direction no other input applied airplane Im working now maintains altitude some dis tance heading changes toward direc tion roll ie pulls toward canopy RVP Obviously aircraft starts approach terra firma bank angle exceeds 450 noth ing oppose gravityno lift up about 450 bank aircraft starts almost circle since normal aircraft center-ofgravity must forward center-of-pressure some amount lest aircraft fall stall tail first circling tendency should ev ident Pattern aircraft some degree other Put another way Pattern aircraft trimmed straight unaccelerated flight will fly both upright inverted altitude change banking wings either upright inverted will produce heading change True way oppose heading change Pattern aircraft rolling maneuver judicious use rudder Which would also mean no such thing axial roll well-trimmed Pattern airplane barrel rolls altitude heading ex cursions too small detect True questions hit heart air planes really fly what differences tween trim stability Let clear air state impossible have airplane has trimmed straight level un accelerated flight rolled inverted have maintain altitude unless several complicated inter actions between engine wings fiAselage horizontal tail just right consider interaction just wings horizontal tail impossible no matter what Thats see few examples airplanes can trim just once both upright inverted flight mechanics level flight simple ten misunderstood shade tree aerody nainicists Im going bore Out skull lot equations just two simple curves will suffice get points across successful flying airplane Continued page 159 SAVE YOUR FIELD SNuF-LER muffler low cost easy install lightweight sound reducing muffler no performance penalty answer AMA muffler rule suggestions saving flying fields Meets AMA muffler rule suggestionsSNUF-LER 3 10 decIbels quieter stock mufflerMUFFLER No power loss possible 300-500 RPM increase Pat Pending Improves engine idle s better fuel economy Easily attached 25-108 stock mufflers Heat corrosion resistant Black E coat finish No special adapters required Weighs 35 oza Fits ASP BRAT ENYA FOX HP IRVINE K & B OS MAX ROYAL YS SUPER TIGRE mufflers available hobby shop ORDER DIRECT immediate shipment Check MO Visa MC CODSEND 25r STAMP accepted Add $250 UPS $205 tsr COD 6% sales taxFOR ADDITIONAL INFO Calif residentAND JTEC CATALOG January 1989 43 qqFP PUT YOURSELF AT ThE CONTROLS OF PROVEN GREAT FLYING WARDIRD almost ready fly kits have wing loadings lighter trainers very docile air land like Cub building-to-flying time very minimal fine kits together skill imagination will make plane crowd pleaser field Retracts now available Strong Light Reliable Pneumatics Idts come furnished fiberglass cowls WrIte call D&R Aircraft Mfg RO Box 23056 in TX 78736 512/288-2055 512/672-7023 Dealer Inquiries Invited $24 95 CAT NO 800 S Balsa0 Cutter5 T001~ 5 pc Masters Set 1/8 3/16 1/4 5/16 3/8 . $1698 3 pc Builders Set 3/161/4 5/16$998 Whether YOU kit builder scratch builder SQUARE CUT Tools will save time Remove stubborn die cuts cut own squares slots Made US quality machined zinc plated steel Order set today See Dealer Cataloger Order dont carry Square Cut Tools call us call well pay shipping SQUARE CUT Tools 4073 254-0516 905 N Harbor City Blvd Melbourne FL 32935 Florida Residents Dealer Distributor Inquiries Invitedadd 6% mien tax yr American Eaglet - was first light-plane receive type certificate Anorioan Eaglet carry two ooersdby LTMJ 05 motorpeople 45 horsepower ohkheosorv-Packooedintoisuros-The Eaglet complete itight system idOSA 1930s contemporary Aeronca C3 Taylor Cubs Health Parasol Pietenpol Air Camper Eaglets gentle flying characteristics reason flying schools day chose standard instructional aircraft Leisures easy-to-build scale model kit Amencan Eaglet 05 electric powered shares gentle Keiths flight itsomething hed wanted 1985 couldnt because Teds preemptive action Anyway seeing oles own design being flown Master happy humbling experience very much enjoyed particular flight Keith routinely flies oth ers models asked OK Mitch Maybe will publish Would like kit Ted sad thing about KRC meet ends good thing have en joyed continuance others hard imagine next year will mark 10th anniversary KRC Electric Fly What began dubious risky one-day affair 1980 tracted three icipants has matured two annual days sheer joy excitement happiness two days re charging friendships associations made past two days new memories ac quaintances formed year two days Electric advancement achievement shared displayed allwith having come mean over 100 participants hundreds spec tators Its heckofa flight folks have comments youd like share other Electrickers Please send themor questions SASE please ad dress given box very beginning column sincere thanks numerous folks came Fly comment favorably column appreciate interest feel ing taking time say flight characteristics full scale aircraft Scaled 18 inches-to-foot model features span 62 inches wing area 571 square inches Its lightweight structure 4041 oz flying weight allows low wing loading 104 ounces per square foot combined Leisure flight system turning 11 x 5 prop flight performance spectacular Takeoff occurs after 20 foot ground roll climb-out brisk model has thermaled moderate lift conditions Gentle landings breeze Scale details documentation included plans make scale contest winner Rsr afree copy Leisures new full color catalog send stamped self addressed business sized envelope Leisure Electrenics Inc 22971 Triton Way Unit B Lesguna Hills C4 92653 RC AerobaticsNan Putte Continued page 43 must able trimned must sta ble airplane trimmed steady level flight forces moments acting must add up zero means lift equals weight thrust equal drag no net pitching moment present two curves referred lift pitching moment curves Figure 1 shows rela tionship between lift generated given speed aircraft angle attack can see theres angle attack lift equals airplane weight airplane must angle attack maintain unaccelerated level flight airspeed chosen exam ple called trim angle attack Theres different trim angle attack another airspeed airplane angle attack higher trim angle attack will tend climb vice versa second Figure 2 curve really set curves shows pitching moment generated stable airplane given speed function airplane angle attack several elevator set tings pitching moment muat zero trim curve can pass through zero pitching moment aircrafts trim angle tack lift equals airplane weight curve labeled E2 corresponds particular elevator position summarize given airspeed angle attack elevator setting airplane will maintain unaccelerated level flight change throttle setting consume fuel trim attitude airplane will change elevator deflection required Leisure achieve will change well have prob ably noted airplanes trim changes fuel consumed flight speed changed Airplanes can designed minimize ef fects will always present degree Now what about William Ropers problem take airplane steady level flight roll 90 roll performed almost about axis line direction airplane flying call rolling about velocity vector airplane rolled 900 about axis lift wing does change However now lift countering airplanes weight fact its pointed perpen dicular Newtons laws obviously work situation airplane accelerates direction perpendicular wings downward well So much mystery What happens airplane rolled less 45 ally same forces present airplane rolled 90 effect reduced Consequently air plane will start gentle turn due unopposed part lift generated wing airplanes descent reduced because substan tial fraction lift available counter airplanes weight Consequently airplane will enter descending torn So does banking produce heading change Yes suggestion made William Roper way oppose heading change rolling maneuver judicious use rudder What suggested true However dont know anyone fast enough right amount rudder counter heading changes good news takes time airplanes heading change very much since supposed perform three rolls five seconds heading changes dont have January 1989 159 New Leisure introduces electric scale American Eaglet responding advertisers mention thatyou read about ModelAviation lot time develop allegation nobody does axial roll true lift force being developed wings rotates around airplane rolls air plane accelerates direction unop posed force means path air plane cannot straight Obviously some air planes better others performing axial rolls barrel roll degree RC Slope Soaring/Triebes Continued page 45 ships Can imagine what would say someone claimed powered plane fully acrobatic asymmetrical wing no rud der same goes Slope Soarers snap rolls four-point rolls clean hammerheads other maneuvers must have rudder side outside maneuvers have same size shape symmetrical alrfoil pretty much necessity almost no Slope kits fully acrobatic writers like yourself keep sisting todays crop planes like Savage its progeny SR-7 forth good are fully aerobatic think will see new breed Another thing will further good designs contests CD thinks nothing call ing outside loops inverted flight rolling circles one-and-a-half snaps vertical eights Jef makes some very good points am sure Slope Soaring continues grow MINI-JET SERIES planes feature balsa construction Designed intermediate flyer in A4 mind will accept 20-25 size engine fuse rear exhaust engine exceptional Skyhawk performancel thrill jet heesles ducted fan $4000 &H Proud Bird deeignad meet OSPRA Formula 120 rules 114 scale model will accept 60-120 ci size engines Epoxy glees fueelage foam wing construction Full kit $150 Semi-kit also available Inn woodi $i25 Please add $10 S&H F-20 Tlgenhark Send check money order COD add $300 esidents add 6% sales tsx Dart ExperImental two-place full size alrr5ft Top Turkey Formula 1 $85$5S&H PARRISH AIRCRAFTScale Models ll25SW49thTer Plantation FL33317 will see new designs emerging number hoped will fully acrobatic Jef also looking some information help him evaluate relative merits different sym metrical airfoils Slope Soaring Aerobatics Any information can get subject would greatly appreciated Jefs name sounds familiar some probably because principal people involved developing Apple Macin tosh computer Jef also wrote program Micro soft Basic Mac will calculate coordi nates display picture NACA fourdigit airfoil appears Martin Hollmanns book Modem Aircraft Design very inter esting us designer types play would like listing program send SASE two stamps please Spitfire Slope LeRoy Satterlee Wa terloo IA sent couple photos beautiful Spitfire Mk XII built John Lupperger Plans Service plans what has say about designed 25-size power plane orig inally did build light leave off engine finished plane flown aile ron elevator no rudder wing loading 925 oz per sq ft made slow est flying Spitfire anyone could remember having seen addition about 10 oz lead picked up flying speed plane flew much solidly experiments will continue re turn hill later year ever build another Spitfire Ill build heavier use thin ner airfoil some kind get speed up further Power Slope Scale fun di version recommend everyone LeRoy flying buddies travel two-and-ahalf hours southeastern Wisconsin Slope flying sald Slope fliers dedi cated Four group including LeRoy have completed LSF Level 5 eight-hour slope flights Superslope Tom Rent member fleer Minnesota RC Soaring Society gives further evidence Slope Soaring alive well Midwest club relatively large approaching 100 members have recently discovered 160 Model Aviation CA MASK CA glue works wonders building models right Unfortunately gives enough fumes knock vulture off carcass modelers have suffered medical problems after inhaling CA fumes take chances special vapor respirator filters CA fumesl soft face mask adjustable straps comfortably fits face sizes easy breathing valve allows prolonged use providing dependable filtering concentrations up 1000 PPM though rugged industrial mask light weight elimi nate fatigue Dont get gassed CA Get protected Order CA Mask today Just $1247 shipping cheaper hospital visit Money order Master Charge Visa include expiration date check allow 20 days clear Sorry no CODs Pelican Enterprises 2540 RIDGE ROAD LANSING ILLINOIS 60438 P S Send catalog modelers safety supplies 305 581-4477 Latest Japanese Pattern Design Designed & Flown TOP Japanese Pilot Suitable FAI AMA Classes tCa5a FberRedewd EtrexyiSasa FuaabgaSpa, -57 wing Area 750 eq 2 Fe 5e Siesied Cake FbarRakfrexedUkeLld HxeepaenA PraitWhrs 3Fadxy5traahd a5patle& raesrieeke 41W errewarhised hedre ed 5 Pawt FeaeI Now Offered Super Deluxe Pm-Built Kit $45000 Completely Finished Model Call info & pricing VISA& MASTERCARD WELCOME Pteae add $t5mt Srr& Hadna inidaadd &5%.15550dntwa&AdaCewayNPhone408298-0311 FAX#408298-6538 IA NEW ELECTRIC Fly .. great stand-way-off scale fun ship designed 05 electric power can perform take-offs touch goes aerobatics beauty yet enjoy docile slow flight easy landings Quick easy build kit includes pre cut fuselage sides tail feathers small parts hardware complete rolled plans step-by-step instructions formed landing gear windshield Electro-Combo includes kit DSC 075 Hyperthrust motor fused switch harness Tamiya connector propeller adaptor 8/4 fiberglass propeller 40 Span 275 Sq area 32 oz flying weight flat bottom airfoil rudder elevator motor add ailerons too SPECIAL COMBO PRICE $4795 IPAVEY675 YSTEMSWEST CHESTEF PA 193& BASIC KIT $244oRRATloN215~ wonderful world Slope Soaring Although true Midwest flat some areas blessed beautiftil grass-covered hills provided retreating glaciers site Superslope call Nerstrand MN perfect come Picture Steep grass-covered face road parking area top wide face no trees unobstructed flatlands below smooth airflow remote location no houses traffic its 30-to-40-minute drive Twin Cities Rochester am continually surprised number Slope fliers located Midwest Slope Soaring has long considered coastal sport caters mainly California crowd rapidly gaining reputation universal branch Soaring Beginner hints letters receive fliers new Slope Soaring ask ing few hints finding good site mak ing first flight help position also remind us little experienced basics Slope fly ing Finding good site really too difficult principle reality may turn out some what harder depending location ex perience ideal slope site would range foothills unobstructed face no trees bushes etc looks prevailing winds Actual size hill really important have flown off 5000-ft peaks off 10ft ridges What important find site faces steady relatively strong 10-30 mph winds will want find hill ridge has clear unobstructed top land ing easiest general really need take Sailplane will fly light conditions day conditions such go out vestigate possible sites cannot really de termine anything about quality site until have flown off Some best sites look nearly good vice versa As flying itself let offer couple comments should get through begin ning stages First predominant lift slope generated area about 450 top hill angle going wind commonly used technique fly back forth across face hill remaining 450 column air really difficult might sound simply location best lift reality lift just about everywhere windward side hill important thing remember get behind hill rotors develop downwind side hill have destroyed Sailplanes characteristic Slope Soaring probably difficult begin ners overcome simplest way keep out trouble imagine wall extends along top hill ridge must remain front wall stay clean air avoid downdrafts other side Once have few hours experience Slope flying will able investigate area tually youll able use advantage landing beginner place stay clear As launching will want take few steps down face hill avoid having plane thrown back behind hill Simply give plane good toss straight wind continue fly straight out until stronger lift Landing quite simple launching still difficult As beginner will probably want land going across face hill simplest surest way getting down getting caught behind hill stalling plane trying slow down too much Just fly plane slowly possible across face slightly below top hill continue lower lower until can land certainly neither pretti est nor purist way land its effective somewhat easier beginner Once have little experience will able use rotors behind hill re duced lift top hill simply lower plane down land top would rec ommend method until have logged few hours comfortable flying slope After said done best way learn fly slope simply probably saying yourself easy say being experienced Sloper just beginner beginners time us learned fly slope just doing methods beginning Sloping have helped people get sport am sure other hints could helpful neophyte know anything think might help someone little no experience slope let know will pass Slope types Another frequently asked question receive just shape slope af fects lift produced slope best way analyze lift site analyze cross sec tion slope specifically angle slope As general rule gentler slope say 300 will produce lighter lift over large area steeper slope approaching January 1989 161 Leo & MODEL BUILDING 7SERVICE RADIO CONTROL FROVUCTS carry full line Byron Originals Bob Parkerson Tom Cook Bob Violet products COD Orders Accepted 718 983-9735 128 WATCHOGUE ROAD EN SlAM 0314 Electric F ight Has Brake Lightweight 12 OLmosey hark Adjustable switching poiut guarantee easy hookup $249 ON/OFF Controller5 Power save weight aiZO Size 22x13x63 Very high efficiency 006' loss Add $105 shippiog Colitorojarosideots add 65% $163 Tss Send Check money order CoasesoithiiHIgh Sky Falaha sonsector Kansas St #9 otEaeeSan DiegoCA 92104 vertical will produce stronger lift over consider ably smaller area other words lift area slope directly related steepness slope wish fly stronger lift use up rel atively little available sky will want fly off cliff similar type slope would rather fly lighter consist ent lift will probably want fly slope quite steep Demon Tweaks have passed around modeling community some time Although theyre aimed specifically Slope Soar er hints trimming out Sailplane can immeasurable help give credit credit due believe Tweaks origi nated Pikes Peak Soaring Society newslet ter Spoiler specifically its edi tor Randy Reynolds Demon Tweak #1Make sure flying sur faces straight can done variety ways favorite simply sight down bottom surface wings stabs rear airplane suspicious surface can dis mounted double-checked flat surface such workbench flat right Trailing edges can sighted down similar manner check trueness particularly critical stab/elevator surfaces Demon Tweak #2It less fashionable days employ washout wing tips Washout trailing edge higher leading edge theory smaller chord tip would stall earlier root thus causing falloff tip another recommendation use washout since difference degree will cause erratic flightpath higher speeds such launch can check models tendency tip stall flight slowly bringing nose up until Glider stalls recovers straight ahead have washout bird good shape Demon Tweak #3Set up center-ofgravity properly Often kit plans call balanc ing spar frequently extremely conservative location will yield excellent sta bility very mediocre performance just learning fly leave ready handle performance should learn measure CG percentage wing chord able relate field experi ences percentage shop has two large blocks spruce tri angular pieces positioned halfway down block determine CG place assembled Glider triangular stock pieces un der wing root Balance Glider fore aft Measure distance triangular piece leading edge calculate per centage against full chord Generally speak ing trainers set up 30-33% Most higher-performance ships happiest 3538% Eppler 205 ships perform best 38% according pilots Use own judg ment wouldnt exceed 37% flatbottom airfoiled ships unless Top Gun caliber Demon Tweak #4Many entry-level ships observed climbing out launch shallow angles yield poor altitude Again kit manu facturers want safe suecessful therefore towhook positions extreme ward Once have learned fundamentals flying time tune towhook position CG Please think two factors insep arable generally place towhook exactly un der CG have always reliable high launches Most fliers position hook somewhat forward location perhaps / aggressive fliers looking maximum alti tude actually place hook behind CG What ever make changes several small steps starting hook ahead CG lo cation Authors note demon tweak obvi ously does apply Slope Soaring al though probably don' like admit some us occasionally some thermal flying Demon Tweak #5Most entry-level ships have narrow speed range would benefit installation turbulator strips devices tend reduce airflow separation top sur face improve performance during slow flight Studies have seen recommend two strips 10% chord measuring leading edge other 20-25% make turbulator strips Goldberg /32 color striping tape Typ ically strip laid directly top another yield bump thats repositionable decora tive tinkerers delight Bump Soaring What world Bump Soar ing Essentially Slope soaring slope thought needed large hill mountain range provide lift needed fly wrong needed create rising air enables Slope ships stay aloft something deflect change direction wind Thus need Bump Soar small ridge bump will deflect wind up wards some relatively strong winds have flown ridges small five six feet high have produced consistent lift winds 25-to-30 mph range lift does extend upwards very high strong enough maintain 25 50 ft altitude work ridge back forth What Bump Soaring does provide Slope flier opportunity polish skills learn mechanics Slope flying What type Sailplane need get volved Bump Soaring Unfortunately high-performance Racing ships just will able find lift needed unless happen flying hurricane-force winds type Sailplane best suited Bump Soaring light weight hand-launch type plane Most lighter thermal ships will able fly kind lift smaller plane better will able manage small lift area tight turns associated Bump Soaring would like try exciting diversion everyday Slope flying give Bump Soaring try very fun exhilarating way polish flying skills have opportunity travel favorite slope slope sites wanted Thanks High Performance Models presents ECL IPSE Designed Henry Piorun Former Canadian National Champion & FAI Canadian Team Member Designed Specifically FAI Pattern Flying Perform Equally Well Other AMA Classes Plug Wings rglass Belly Pan Pre-Cut Moles br Wing Joiner Tubes Ultralight Honeycomb Wingoores xfra404601 Optional Plastic Fiberglass Canopy Fiberglass Fuselage molded wing Joiner tube HIGH PERFORMANCE MODELS 9556116 st North Delta British Columbia 6Z4 Canada 604-588-0605 FINALLY Ultimate BOARD Designed & engineered WARP FREE construction HIGH-TECH MATERIAL Portable Ughtweight Conveniently Stored Large 20x78 Endgrain balsa block pin surface 314 deep Unaffected temperature humidity CASH PRICE $1 3500 Cai UPS VBA & MC 3700 BOULDER PORT ARTHUR TX 17640 409-982-8717 -F-who have sent details about favorite fly ing sites Although have received information number sites would really like have quite few put together really thorough complete directory slope sites send information favorite site please include such things prevailing winds slope gle landing area characteristics quality lift recommended flying experience directions and/or map local contact possible photo site Thanks again help project RC Scale/SruII Continued page 47 lected subtle shading keyword subtle Dont panels dont overdo Two colors will required high lights shadows Using basic air craft finish color add little white high light color little black shadow color Experiment first some scrap paper before tacking model Spray shadows first add highlights Remember Go easy dont overdo other method requires model sub structure supporting skin less scale model covered skinned somewhat flexible material does tally hide supporting substructure Major bulkheads stringers ribs spars model should located scale positions wherever pos sible Its usually good idea follow fullscale prototype structural layout anyhow scratch-building model rather totally re engineer perfectly good full-scale airplane de sign Rather using relatively stiff balsa skin typical balsa stock would firm %2 sheet plank model want use strong flexible covering material skin should flex distort small amount make internal structure visiblelike prototype Zero starved horse look usually work hard avoid just thing trying achieve case two materials have experience job nicely / ply /~ balsa / ply has very good tensile strength plus some flexibility best suited larger Scale models easiest use large pieces surfaces devoid compound curves such wing skins /16 firm balsa covering well-sanded %2 soft balsa well suited small-to-moderatesize models %- A-scale easy apply compound- high-curvature surfaces Being flexible will tend sag ripple /64 ply So depending scale model local skin strength required choose whichever best suits need case balsa skin will require layer lightweight glass cloth after attached framework will provide needed strength balsa well making surface hard enough finish standard practice edgegluing balsa sheets sanding smooth finish before attaching framework applies thin-skin structure used fi nal touch panel ripple should applied airbrush authentic look Now lets hear wrinkied-skin Zeros about target tow option least-seen interesting flight options suit able number Scale aircraft subjects target tow military training aircraft dating back Thirties pressed ser vice during WV II tow various flag sleeve targets use ground-to-air air-to-air gun nery practice An example Dreadnought version British Hawker Sea Fury fighter shown page 92 November 1988 issue MA nice plus target-tow airplanes sport interestlng distinctiveif garish color schemes ideal Scale model use sim ple reason bright color schemes flight crews wanted make absolutely sure tow aircraft could clearly seen dis tinguishable target sleeve nearsighted rookie gunnery student Though very interesting target tow simpler flight options Properly done INTRODUCING THE ELE7/JL/FE FOR 020-035-050 ELECTRICI\r SPAN 36 AREA 25T CHANNELS 2-3 ONOTH 3T FLYING WY 20 TO 30 OZ Designed built EIecSrlo Model Co 218 Oyster Ck r Land TX 77478 242-6229 Souths ingest inventory satro motors & accessories Need help wIth yow electdc ahplm orglder Ask Doe j~DuaIStrut Nose Gear Fults Tooling PO Box 95 Champaign IL 61820 NumberflistanReCe SF350 5 95 SF400 6 95 SF500 32 66901695 RF500 32 96-121595 RFY5T 321 SCSI1565 AAIosIabRGuadla OFROTlAs3116 1 seal 2995 PRODUCTS FOR THE DISCERNING MODELER Complete Line Exhaust Systems * Tuned led Tuned Pipes Headers uri Mufflers * Expansion Mufflers copter Ball Mufflers * Specialized Exhaust Systems Unsurpassed January 1989 163 Yes Virginia Santa Claus 2z Get Nearest Santas Shop 5sPeopIeof Com6ddem /mkc74 Aec Instantly removable sri-cycle gear wheels Pre-built boom landing gear sockets 8 push-roth Astro motor mount cobalt adapter Preformed leading edges knotched trailing edges Air frame 6 oz 75 ox landing gear Perfect performance 02003535 systems Maximum duration 8 glider-like motor-ofi flight characteristics ARF build 8 cover wing also completely built tail surfaces hinged . $7996 w/o gear $8695 gear ladd $3 eftipping TX res add 6% sales taxi
Edition: Model Aviation - 1989/01
Page Numbers: 42, 43, 159, 160, 161, 162, 163
QUESTIONS often appear letters arrive mail box following letter addressed Model Aviation forwarded pub lisher may concern ve flying RC planes about 4/2 years now started Goldberg Eagle 63 Over time able perform various stunts such loops barrel rolls inverted flight touch-and-go etc recently purchased built Goldberg Sky Tiger problem cant get plane turn rudder left right use rudder plane does flat turn cant get plane bank unless use ailerons banldng try level plane out rudder acts its sideslipping Say Im banking right give left rudder roll out bank Instead plane rolling left level flight plane stays bank nose goes up doing sideways flat turn tends cause loss altitude cant life figure problem out control throws set according instructions now need some experi enced advice correcting matter plane flies well except fact cant use rudder turn letter signed John Fleming Vernon NY wrote letter John rea lized problem might shared number fliers hadnt written letters Model Aviation seeking help information Its easy understand lack rolling response rudder control input would cause pilot accustomed beginner-type aircraft think problem perhaps ginner aircraft intentionally have too much dihe dral wing Consequently rudder deflected airplane starts sideslip dihedral wing generates rolling moment airplane banks direction rudder deflected So pilot thinks rudder caused bank Well suppose rudder did cause bank couldnt have happened wing dihedral So have two ways bank airplane rudder ailerons Thats good Right really Using rudder bank air plane fine long dont want turn airplane beginner airplanes dont have ailerons perform missions very well rather abrupt turns performed using rudder/wing dihedral banldng mechanism its hard tell Lift Airplane Weight Angle Attack atrim Figure 1 Ron discusses stability trim answers questions about Pattern models seemingly inexplicable things sometimes figure porlrays unique wing angle tack s needed sustain airplane level unaccelerated flight particular airspeed turns arent being done using ailerons However reason using rudder bank airplane satisfactory beginners dont tend fly airplanes inverted per form maneuvers like knife-edge flight point rolls want progress flying advanced ma neuvers must have airplane does bank rudder deflected roll airplane knife-edge apply top rud der keep nose up dont want wing dihedral cause airplane roll So benchmarks airplane Pattern flying potential absence rolling ten dency rudder deflected goal learn fly Pattern ma neuvers can bank airplane rudder reduce wing dihedral until doesnt What did tell John Fleming Sky Tiger doing just what its supposed Dont change anything Another letter arrived Wil liam Roper Englewood CO wrote long Pitching Moment Angle Attack atrim E3 Figure 2 series curves illustrtates pitching moments generated stable air plane constant airspeed several different elevator deflections E1 E2 E2 order trim plane unique elevator deflection generating zero pitching moment trim angle attack attm found Figure 1 necessary Only elevator deflectIon satisfies things 42 Model Aviation Radio Cono Sport Aerobatics Ron Van Putte Ill Sleepy Oaks Rd Ft Walton Beach FL 32548 happens pros AMA President Don Lowe examines spot cov ering missing wing Phoe nix 9 sure makes funny sound de parts during flight letter suppositions questions Wont quote whole letter just part along responses William started out like What Im trying sort out straight level unaccelerated flight Pattern airplane slowly rolled 900 either direction no other input applied airplane Im working now maintains altitude some dis tance heading changes toward direc tion roll ie pulls toward canopy RVP Obviously aircraft starts approach terra firma bank angle exceeds 450 noth ing oppose gravityno lift up about 450 bank aircraft starts almost circle since normal aircraft center-ofgravity must forward center-of-pressure some amount lest aircraft fall stall tail first circling tendency should ev ident Pattern aircraft some degree other Put another way Pattern aircraft trimmed straight unaccelerated flight will fly both upright inverted altitude change banking wings either upright inverted will produce heading change True way oppose heading change Pattern aircraft rolling maneuver judicious use rudder Which would also mean no such thing axial roll well-trimmed Pattern airplane barrel rolls altitude heading ex cursions too small detect True questions hit heart air planes really fly what differences tween trim stability Let clear air state impossible have airplane has trimmed straight level un accelerated flight rolled inverted have maintain altitude unless several complicated inter actions between engine wings fiAselage horizontal tail just right consider interaction just wings horizontal tail impossible no matter what Thats see few examples airplanes can trim just once both upright inverted flight mechanics level flight simple ten misunderstood shade tree aerody nainicists Im going bore Out skull lot equations just two simple curves will suffice get points across successful flying airplane Continued page 159 SAVE YOUR FIELD SNuF-LER muffler low cost easy install lightweight sound reducing muffler no performance penalty answer AMA muffler rule suggestions saving flying fields Meets AMA muffler rule suggestionsSNUF-LER 3 10 decIbels quieter stock mufflerMUFFLER No power loss possible 300-500 RPM increase Pat Pending Improves engine idle s better fuel economy Easily attached 25-108 stock mufflers Heat corrosion resistant Black E coat finish No special adapters required Weighs 35 oza Fits ASP BRAT ENYA FOX HP IRVINE K & B OS MAX ROYAL YS SUPER TIGRE mufflers available hobby shop ORDER DIRECT immediate shipment Check MO Visa MC CODSEND 25r STAMP accepted Add $250 UPS $205 tsr COD 6% sales taxFOR ADDITIONAL INFO Calif residentAND JTEC CATALOG January 1989 43 qqFP PUT YOURSELF AT ThE CONTROLS OF PROVEN GREAT FLYING WARDIRD almost ready fly kits have wing loadings lighter trainers very docile air land like Cub building-to-flying time very minimal fine kits together skill imagination will make plane crowd pleaser field Retracts now available Strong Light Reliable Pneumatics Idts come furnished fiberglass cowls WrIte call D&R Aircraft Mfg RO Box 23056 in TX 78736 512/288-2055 512/672-7023 Dealer Inquiries Invited $24 95 CAT NO 800 S Balsa0 Cutter5 T001~ 5 pc Masters Set 1/8 3/16 1/4 5/16 3/8 . $1698 3 pc Builders Set 3/161/4 5/16$998 Whether YOU kit builder scratch builder SQUARE CUT Tools will save time Remove stubborn die cuts cut own squares slots Made US quality machined zinc plated steel Order set today See Dealer Cataloger Order dont carry Square Cut Tools call us call well pay shipping SQUARE CUT Tools 4073 254-0516 905 N Harbor City Blvd Melbourne FL 32935 Florida Residents Dealer Distributor Inquiries Invitedadd 6% mien tax yr American Eaglet - was first light-plane receive type certificate Anorioan Eaglet carry two ooersdby LTMJ 05 motorpeople 45 horsepower ohkheosorv-Packooedintoisuros-The Eaglet complete itight system idOSA 1930s contemporary Aeronca C3 Taylor Cubs Health Parasol Pietenpol Air Camper Eaglets gentle flying characteristics reason flying schools day chose standard instructional aircraft Leisures easy-to-build scale model kit Amencan Eaglet 05 electric powered shares gentle Keiths flight itsomething hed wanted 1985 couldnt because Teds preemptive action Anyway seeing oles own design being flown Master happy humbling experience very much enjoyed particular flight Keith routinely flies oth ers models asked OK Mitch Maybe will publish Would like kit Ted sad thing about KRC meet ends good thing have en joyed continuance others hard imagine next year will mark 10th anniversary KRC Electric Fly What began dubious risky one-day affair 1980 tracted three icipants has matured two annual days sheer joy excitement happiness two days re charging friendships associations made past two days new memories ac quaintances formed year two days Electric advancement achievement shared displayed allwith having come mean over 100 participants hundreds spec tators Its heckofa flight folks have comments youd like share other Electrickers Please send themor questions SASE please ad dress given box very beginning column sincere thanks numerous folks came Fly comment favorably column appreciate interest feel ing taking time say flight characteristics full scale aircraft Scaled 18 inches-to-foot model features span 62 inches wing area 571 square inches Its lightweight structure 4041 oz flying weight allows low wing loading 104 ounces per square foot combined Leisure flight system turning 11 x 5 prop flight performance spectacular Takeoff occurs after 20 foot ground roll climb-out brisk model has thermaled moderate lift conditions Gentle landings breeze Scale details documentation included plans make scale contest winner Rsr afree copy Leisures new full color catalog send stamped self addressed business sized envelope Leisure Electrenics Inc 22971 Triton Way Unit B Lesguna Hills C4 92653 RC AerobaticsNan Putte Continued page 43 must able trimned must sta ble airplane trimmed steady level flight forces moments acting must add up zero means lift equals weight thrust equal drag no net pitching moment present two curves referred lift pitching moment curves Figure 1 shows rela tionship between lift generated given speed aircraft angle attack can see theres angle attack lift equals airplane weight airplane must angle attack maintain unaccelerated level flight airspeed chosen exam ple called trim angle attack Theres different trim angle attack another airspeed airplane angle attack higher trim angle attack will tend climb vice versa second Figure 2 curve really set curves shows pitching moment generated stable airplane given speed function airplane angle attack several elevator set tings pitching moment muat zero trim curve can pass through zero pitching moment aircrafts trim angle tack lift equals airplane weight curve labeled E2 corresponds particular elevator position summarize given airspeed angle attack elevator setting airplane will maintain unaccelerated level flight change throttle setting consume fuel trim attitude airplane will change elevator deflection required Leisure achieve will change well have prob ably noted airplanes trim changes fuel consumed flight speed changed Airplanes can designed minimize ef fects will always present degree Now what about William Ropers problem take airplane steady level flight roll 90 roll performed almost about axis line direction airplane flying call rolling about velocity vector airplane rolled 900 about axis lift wing does change However now lift countering airplanes weight fact its pointed perpen dicular Newtons laws obviously work situation airplane accelerates direction perpendicular wings downward well So much mystery What happens airplane rolled less 45 ally same forces present airplane rolled 90 effect reduced Consequently air plane will start gentle turn due unopposed part lift generated wing airplanes descent reduced because substan tial fraction lift available counter airplanes weight Consequently airplane will enter descending torn So does banking produce heading change Yes suggestion made William Roper way oppose heading change rolling maneuver judicious use rudder What suggested true However dont know anyone fast enough right amount rudder counter heading changes good news takes time airplanes heading change very much since supposed perform three rolls five seconds heading changes dont have January 1989 159 New Leisure introduces electric scale American Eaglet responding advertisers mention thatyou read about ModelAviation lot time develop allegation nobody does axial roll true lift force being developed wings rotates around airplane rolls air plane accelerates direction unop posed force means path air plane cannot straight Obviously some air planes better others performing axial rolls barrel roll degree RC Slope Soaring/Triebes Continued page 45 ships Can imagine what would say someone claimed powered plane fully acrobatic asymmetrical wing no rud der same goes Slope Soarers snap rolls four-point rolls clean hammerheads other maneuvers must have rudder side outside maneuvers have same size shape symmetrical alrfoil pretty much necessity almost no Slope kits fully acrobatic writers like yourself keep sisting todays crop planes like Savage its progeny SR-7 forth good are fully aerobatic think will see new breed Another thing will further good designs contests CD thinks nothing call ing outside loops inverted flight rolling circles one-and-a-half snaps vertical eights Jef makes some very good points am sure Slope Soaring continues grow MINI-JET SERIES planes feature balsa construction Designed intermediate flyer in A4 mind will accept 20-25 size engine fuse rear exhaust engine exceptional Skyhawk performancel thrill jet heesles ducted fan $4000 &H Proud Bird deeignad meet OSPRA Formula 120 rules 114 scale model will accept 60-120 ci size engines Epoxy glees fueelage foam wing construction Full kit $150 Semi-kit also available Inn woodi $i25 Please add $10 S&H F-20 Tlgenhark Send check money order COD add $300 esidents add 6% sales tsx Dart ExperImental two-place full size alrr5ft Top Turkey Formula 1 $85$5S&H PARRISH AIRCRAFTScale Models ll25SW49thTer Plantation FL33317 will see new designs emerging number hoped will fully acrobatic Jef also looking some information help him evaluate relative merits different sym metrical airfoils Slope Soaring Aerobatics Any information can get subject would greatly appreciated Jefs name sounds familiar some probably because principal people involved developing Apple Macin tosh computer Jef also wrote program Micro soft Basic Mac will calculate coordi nates display picture NACA fourdigit airfoil appears Martin Hollmanns book Modem Aircraft Design very inter esting us designer types play would like listing program send SASE two stamps please Spitfire Slope LeRoy Satterlee Wa terloo IA sent couple photos beautiful Spitfire Mk XII built John Lupperger Plans Service plans what has say about designed 25-size power plane orig inally did build light leave off engine finished plane flown aile ron elevator no rudder wing loading 925 oz per sq ft made slow est flying Spitfire anyone could remember having seen addition about 10 oz lead picked up flying speed plane flew much solidly experiments will continue re turn hill later year ever build another Spitfire Ill build heavier use thin ner airfoil some kind get speed up further Power Slope Scale fun di version recommend everyone LeRoy flying buddies travel two-and-ahalf hours southeastern Wisconsin Slope flying sald Slope fliers dedi cated Four group including LeRoy have completed LSF Level 5 eight-hour slope flights Superslope Tom Rent member fleer Minnesota RC Soaring Society gives further evidence Slope Soaring alive well Midwest club relatively large approaching 100 members have recently discovered 160 Model Aviation CA MASK CA glue works wonders building models right Unfortunately gives enough fumes knock vulture off carcass modelers have suffered medical problems after inhaling CA fumes take chances special vapor respirator filters CA fumesl soft face mask adjustable straps comfortably fits face sizes easy breathing valve allows prolonged use providing dependable filtering concentrations up 1000 PPM though rugged industrial mask light weight elimi nate fatigue Dont get gassed CA Get protected Order CA Mask today Just $1247 shipping cheaper hospital visit Money order Master Charge Visa include expiration date check allow 20 days clear Sorry no CODs Pelican Enterprises 2540 RIDGE ROAD LANSING ILLINOIS 60438 P S Send catalog modelers safety supplies 305 581-4477 Latest Japanese Pattern Design Designed & Flown TOP Japanese Pilot Suitable FAI AMA Classes tCa5a FberRedewd EtrexyiSasa FuaabgaSpa, -57 wing Area 750 eq 2 Fe 5e Siesied Cake FbarRakfrexedUkeLld HxeepaenA PraitWhrs 3Fadxy5traahd a5patle& raesrieeke 41W errewarhised hedre ed 5 Pawt FeaeI Now Offered Super Deluxe Pm-Built Kit $45000 Completely Finished Model Call info & pricing VISA& MASTERCARD WELCOME Pteae add $t5mt Srr& Hadna inidaadd &5%.15550dntwa&AdaCewayNPhone408298-0311 FAX#408298-6538 IA NEW ELECTRIC Fly .. great stand-way-off scale fun ship designed 05 electric power can perform take-offs touch goes aerobatics beauty yet enjoy docile slow flight easy landings Quick easy build kit includes pre cut fuselage sides tail feathers small parts hardware complete rolled plans step-by-step instructions formed landing gear windshield Electro-Combo includes kit DSC 075 Hyperthrust motor fused switch harness Tamiya connector propeller adaptor 8/4 fiberglass propeller 40 Span 275 Sq area 32 oz flying weight flat bottom airfoil rudder elevator motor add ailerons too SPECIAL COMBO PRICE $4795 IPAVEY675 YSTEMSWEST CHESTEF PA 193& BASIC KIT $244oRRATloN215~ wonderful world Slope Soaring Although true Midwest flat some areas blessed beautiftil grass-covered hills provided retreating glaciers site Superslope call Nerstrand MN perfect come Picture Steep grass-covered face road parking area top wide face no trees unobstructed flatlands below smooth airflow remote location no houses traffic its 30-to-40-minute drive Twin Cities Rochester am continually surprised number Slope fliers located Midwest Slope Soaring has long considered coastal sport caters mainly California crowd rapidly gaining reputation universal branch Soaring Beginner hints letters receive fliers new Slope Soaring ask ing few hints finding good site mak ing first flight help position also remind us little experienced basics Slope fly ing Finding good site really too difficult principle reality may turn out some what harder depending location ex perience ideal slope site would range foothills unobstructed face no trees bushes etc looks prevailing winds Actual size hill really important have flown off 5000-ft peaks off 10ft ridges What important find site faces steady relatively strong 10-30 mph winds will want find hill ridge has clear unobstructed top land ing easiest general really need take Sailplane will fly light conditions day conditions such go out vestigate possible sites cannot really de termine anything about quality site until have flown off Some best sites look nearly good vice versa As flying itself let offer couple comments should get through begin ning stages First predominant lift slope generated area about 450 top hill angle going wind commonly used technique fly back forth across face hill remaining 450 column air really difficult might sound simply location best lift reality lift just about everywhere windward side hill important thing remember get behind hill rotors develop downwind side hill have destroyed Sailplanes characteristic Slope Soaring probably difficult begin ners overcome simplest way keep out trouble imagine wall extends along top hill ridge must remain front wall stay clean air avoid downdrafts other side Once have few hours experience Slope flying will able investigate area tually youll able use advantage landing beginner place stay clear As launching will want take few steps down face hill avoid having plane thrown back behind hill Simply give plane good toss straight wind continue fly straight out until stronger lift Landing quite simple launching still difficult As beginner will probably want land going across face hill simplest surest way getting down getting caught behind hill stalling plane trying slow down too much Just fly plane slowly possible across face slightly below top hill continue lower lower until can land certainly neither pretti est nor purist way land its effective somewhat easier beginner Once have little experience will able use rotors behind hill re duced lift top hill simply lower plane down land top would rec ommend method until have logged few hours comfortable flying slope After said done best way learn fly slope simply probably saying yourself easy say being experienced Sloper just beginner beginners time us learned fly slope just doing methods beginning Sloping have helped people get sport am sure other hints could helpful neophyte know anything think might help someone little no experience slope let know will pass Slope types Another frequently asked question receive just shape slope af fects lift produced slope best way analyze lift site analyze cross sec tion slope specifically angle slope As general rule gentler slope say 300 will produce lighter lift over large area steeper slope approaching January 1989 161 Leo & MODEL BUILDING 7SERVICE RADIO CONTROL FROVUCTS carry full line Byron Originals Bob Parkerson Tom Cook Bob Violet products COD Orders Accepted 718 983-9735 128 WATCHOGUE ROAD EN SlAM 0314 Electric F ight Has Brake Lightweight 12 OLmosey hark Adjustable switching poiut guarantee easy hookup $249 ON/OFF Controller5 Power save weight aiZO Size 22x13x63 Very high efficiency 006' loss Add $105 shippiog Colitorojarosideots add 65% $163 Tss Send Check money order CoasesoithiiHIgh Sky Falaha sonsector Kansas St #9 otEaeeSan DiegoCA 92104 vertical will produce stronger lift over consider ably smaller area other words lift area slope directly related steepness slope wish fly stronger lift use up rel atively little available sky will want fly off cliff similar type slope would rather fly lighter consist ent lift will probably want fly slope quite steep Demon Tweaks have passed around modeling community some time Although theyre aimed specifically Slope Soar er hints trimming out Sailplane can immeasurable help give credit credit due believe Tweaks origi nated Pikes Peak Soaring Society newslet ter Spoiler specifically its edi tor Randy Reynolds Demon Tweak #1Make sure flying sur faces straight can done variety ways favorite simply sight down bottom surface wings stabs rear airplane suspicious surface can dis mounted double-checked flat surface such workbench flat right Trailing edges can sighted down similar manner check trueness particularly critical stab/elevator surfaces Demon Tweak #2It less fashionable days employ washout wing tips Washout trailing edge higher leading edge theory smaller chord tip would stall earlier root thus causing falloff tip another recommendation use washout since difference degree will cause erratic flightpath higher speeds such launch can check models tendency tip stall flight slowly bringing nose up until Glider stalls recovers straight ahead have washout bird good shape Demon Tweak #3Set up center-ofgravity properly Often kit plans call balanc ing spar frequently extremely conservative location will yield excellent sta bility very mediocre performance just learning fly leave ready handle performance should learn measure CG percentage wing chord able relate field experi ences percentage shop has two large blocks spruce tri angular pieces positioned halfway down block determine CG place assembled Glider triangular stock pieces un der wing root Balance Glider fore aft Measure distance triangular piece leading edge calculate per centage against full chord Generally speak ing trainers set up 30-33% Most higher-performance ships happiest 3538% Eppler 205 ships perform best 38% according pilots Use own judg ment wouldnt exceed 37% flatbottom airfoiled ships unless Top Gun caliber Demon Tweak #4Many entry-level ships observed climbing out launch shallow angles yield poor altitude Again kit manu facturers want safe suecessful therefore towhook positions extreme ward Once have learned fundamentals flying time tune towhook position CG Please think two factors insep arable generally place towhook exactly un der CG have always reliable high launches Most fliers position hook somewhat forward location perhaps / aggressive fliers looking maximum alti tude actually place hook behind CG What ever make changes several small steps starting hook ahead CG lo cation Authors note demon tweak obvi ously does apply Slope Soaring al though probably don' like admit some us occasionally some thermal flying Demon Tweak #5Most entry-level ships have narrow speed range would benefit installation turbulator strips devices tend reduce airflow separation top sur face improve performance during slow flight Studies have seen recommend two strips 10% chord measuring leading edge other 20-25% make turbulator strips Goldberg /32 color striping tape Typ ically strip laid directly top another yield bump thats repositionable decora tive tinkerers delight Bump Soaring What world Bump Soar ing Essentially Slope soaring slope thought needed large hill mountain range provide lift needed fly wrong needed create rising air enables Slope ships stay aloft something deflect change direction wind Thus need Bump Soar small ridge bump will deflect wind up wards some relatively strong winds have flown ridges small five six feet high have produced consistent lift winds 25-to-30 mph range lift does extend upwards very high strong enough maintain 25 50 ft altitude work ridge back forth What Bump Soaring does provide Slope flier opportunity polish skills learn mechanics Slope flying What type Sailplane need get volved Bump Soaring Unfortunately high-performance Racing ships just will able find lift needed unless happen flying hurricane-force winds type Sailplane best suited Bump Soaring light weight hand-launch type plane Most lighter thermal ships will able fly kind lift smaller plane better will able manage small lift area tight turns associated Bump Soaring would like try exciting diversion everyday Slope flying give Bump Soaring try very fun exhilarating way polish flying skills have opportunity travel favorite slope slope sites wanted Thanks High Performance Models presents ECL IPSE Designed Henry Piorun Former Canadian National Champion & FAI Canadian Team Member Designed Specifically FAI Pattern Flying Perform Equally Well Other AMA Classes Plug Wings rglass Belly Pan Pre-Cut Moles br Wing Joiner Tubes Ultralight Honeycomb Wingoores xfra404601 Optional Plastic Fiberglass Canopy Fiberglass Fuselage molded wing Joiner tube HIGH PERFORMANCE MODELS 9556116 st North Delta British Columbia 6Z4 Canada 604-588-0605 FINALLY Ultimate BOARD Designed & engineered WARP FREE construction HIGH-TECH MATERIAL Portable Ughtweight Conveniently Stored Large 20x78 Endgrain balsa block pin surface 314 deep Unaffected temperature humidity CASH PRICE $1 3500 Cai UPS VBA & MC 3700 BOULDER PORT ARTHUR TX 17640 409-982-8717 -F-who have sent details about favorite fly ing sites Although have received information number sites would really like have quite few put together really thorough complete directory slope sites send information favorite site please include such things prevailing winds slope gle landing area characteristics quality lift recommended flying experience directions and/or map local contact possible photo site Thanks again help project RC Scale/SruII Continued page 47 lected subtle shading keyword subtle Dont panels dont overdo Two colors will required high lights shadows Using basic air craft finish color add little white high light color little black shadow color Experiment first some scrap paper before tacking model Spray shadows first add highlights Remember Go easy dont overdo other method requires model sub structure supporting skin less scale model covered skinned somewhat flexible material does tally hide supporting substructure Major bulkheads stringers ribs spars model should located scale positions wherever pos sible Its usually good idea follow fullscale prototype structural layout anyhow scratch-building model rather totally re engineer perfectly good full-scale airplane de sign Rather using relatively stiff balsa skin typical balsa stock would firm %2 sheet plank model want use strong flexible covering material skin should flex distort small amount make internal structure visiblelike prototype Zero starved horse look usually work hard avoid just thing trying achieve case two materials have experience job nicely / ply /~ balsa / ply has very good tensile strength plus some flexibility best suited larger Scale models easiest use large pieces surfaces devoid compound curves such wing skins /16 firm balsa covering well-sanded %2 soft balsa well suited small-to-moderatesize models %- A-scale easy apply compound- high-curvature surfaces Being flexible will tend sag ripple /64 ply So depending scale model local skin strength required choose whichever best suits need case balsa skin will require layer lightweight glass cloth after attached framework will provide needed strength balsa well making surface hard enough finish standard practice edgegluing balsa sheets sanding smooth finish before attaching framework applies thin-skin structure used fi nal touch panel ripple should applied airbrush authentic look Now lets hear wrinkied-skin Zeros about target tow option least-seen interesting flight options suit able number Scale aircraft subjects target tow military training aircraft dating back Thirties pressed ser vice during WV II tow various flag sleeve targets use ground-to-air air-to-air gun nery practice An example Dreadnought version British Hawker Sea Fury fighter shown page 92 November 1988 issue MA nice plus target-tow airplanes sport interestlng distinctiveif garish color schemes ideal Scale model use sim ple reason bright color schemes flight crews wanted make absolutely sure tow aircraft could clearly seen dis tinguishable target sleeve nearsighted rookie gunnery student Though very interesting target tow simpler flight options Properly done INTRODUCING THE ELE7/JL/FE FOR 020-035-050 ELECTRICI\r SPAN 36 AREA 25T CHANNELS 2-3 ONOTH 3T FLYING WY 20 TO 30 OZ Designed built EIecSrlo Model Co 218 Oyster Ck r Land TX 77478 242-6229 Souths ingest inventory satro motors & accessories Need help wIth yow electdc ahplm orglder Ask Doe j~DuaIStrut Nose Gear Fults Tooling PO Box 95 Champaign IL 61820 NumberflistanReCe SF350 5 95 SF400 6 95 SF500 32 66901695 RF500 32 96-121595 RFY5T 321 SCSI1565 AAIosIabRGuadla OFROTlAs3116 1 seal 2995 PRODUCTS FOR THE DISCERNING MODELER Complete Line Exhaust Systems * Tuned led Tuned Pipes Headers uri Mufflers * Expansion Mufflers copter Ball Mufflers * Specialized Exhaust Systems Unsurpassed January 1989 163 Yes Virginia Santa Claus 2z Get Nearest Santas Shop 5sPeopIeof Com6ddem /mkc74 Aec Instantly removable sri-cycle gear wheels Pre-built boom landing gear sockets 8 push-roth Astro motor mount cobalt adapter Preformed leading edges knotched trailing edges Air frame 6 oz 75 ox landing gear Perfect performance 02003535 systems Maximum duration 8 glider-like motor-ofi flight characteristics ARF build 8 cover wing also completely built tail surfaces hinged . $7996 w/o gear $8695 gear ladd $3 eftipping TX res add 6% sales taxi
Edition: Model Aviation - 1989/01
Page Numbers: 42, 43, 159, 160, 161, 162, 163
QUESTIONS often appear letters arrive mail box following letter addressed Model Aviation forwarded pub lisher may concern ve flying RC planes about 4/2 years now started Goldberg Eagle 63 Over time able perform various stunts such loops barrel rolls inverted flight touch-and-go etc recently purchased built Goldberg Sky Tiger problem cant get plane turn rudder left right use rudder plane does flat turn cant get plane bank unless use ailerons banldng try level plane out rudder acts its sideslipping Say Im banking right give left rudder roll out bank Instead plane rolling left level flight plane stays bank nose goes up doing sideways flat turn tends cause loss altitude cant life figure problem out control throws set according instructions now need some experi enced advice correcting matter plane flies well except fact cant use rudder turn letter signed John Fleming Vernon NY wrote letter John rea lized problem might shared number fliers hadnt written letters Model Aviation seeking help information Its easy understand lack rolling response rudder control input would cause pilot accustomed beginner-type aircraft think problem perhaps ginner aircraft intentionally have too much dihe dral wing Consequently rudder deflected airplane starts sideslip dihedral wing generates rolling moment airplane banks direction rudder deflected So pilot thinks rudder caused bank Well suppose rudder did cause bank couldnt have happened wing dihedral So have two ways bank airplane rudder ailerons Thats good Right really Using rudder bank air plane fine long dont want turn airplane beginner airplanes dont have ailerons perform missions very well rather abrupt turns performed using rudder/wing dihedral banldng mechanism its hard tell Lift Airplane Weight Angle Attack atrim Figure 1 Ron discusses stability trim answers questions about Pattern models seemingly inexplicable things sometimes figure porlrays unique wing angle tack s needed sustain airplane level unaccelerated flight particular airspeed turns arent being done using ailerons However reason using rudder bank airplane satisfactory beginners dont tend fly airplanes inverted per form maneuvers like knife-edge flight point rolls want progress flying advanced ma neuvers must have airplane does bank rudder deflected roll airplane knife-edge apply top rud der keep nose up dont want wing dihedral cause airplane roll So benchmarks airplane Pattern flying potential absence rolling ten dency rudder deflected goal learn fly Pattern ma neuvers can bank airplane rudder reduce wing dihedral until doesnt What did tell John Fleming Sky Tiger doing just what its supposed Dont change anything Another letter arrived Wil liam Roper Englewood CO wrote long Pitching Moment Angle Attack atrim E3 Figure 2 series curves illustrtates pitching moments generated stable air plane constant airspeed several different elevator deflections E1 E2 E2 order trim plane unique elevator deflection generating zero pitching moment trim angle attack attm found Figure 1 necessary Only elevator deflectIon satisfies things 42 Model Aviation Radio Cono Sport Aerobatics Ron Van Putte Ill Sleepy Oaks Rd Ft Walton Beach FL 32548 happens pros AMA President Don Lowe examines spot cov ering missing wing Phoe nix 9 sure makes funny sound de parts during flight letter suppositions questions Wont quote whole letter just part along responses William started out like What Im trying sort out straight level unaccelerated flight Pattern airplane slowly rolled 900 either direction no other input applied airplane Im working now maintains altitude some dis tance heading changes toward direc tion roll ie pulls toward canopy RVP Obviously aircraft starts approach terra firma bank angle exceeds 450 noth ing oppose gravityno lift up about 450 bank aircraft starts almost circle since normal aircraft center-ofgravity must forward center-of-pressure some amount lest aircraft fall stall tail first circling tendency should ev ident Pattern aircraft some degree other Put another way Pattern aircraft trimmed straight unaccelerated flight will fly both upright inverted altitude change banking wings either upright inverted will produce heading change True way oppose heading change Pattern aircraft rolling maneuver judicious use rudder Which would also mean no such thing axial roll well-trimmed Pattern airplane barrel rolls altitude heading ex cursions too small detect True questions hit heart air planes really fly what differences tween trim stability Let clear air state impossible have airplane has trimmed straight level un accelerated flight rolled inverted have maintain altitude unless several complicated inter actions between engine wings fiAselage horizontal tail just right consider interaction just wings horizontal tail impossible no matter what Thats see few examples airplanes can trim just once both upright inverted flight mechanics level flight simple ten misunderstood shade tree aerody nainicists Im going bore Out skull lot equations just two simple curves will suffice get points across successful flying airplane Continued page 159 SAVE YOUR FIELD SNuF-LER muffler low cost easy install lightweight sound reducing muffler no performance penalty answer AMA muffler rule suggestions saving flying fields Meets AMA muffler rule suggestionsSNUF-LER 3 10 decIbels quieter stock mufflerMUFFLER No power loss possible 300-500 RPM increase Pat Pending Improves engine idle s better fuel economy Easily attached 25-108 stock mufflers Heat corrosion resistant Black E coat finish No special adapters required Weighs 35 oza Fits ASP BRAT ENYA FOX HP IRVINE K & B OS MAX ROYAL YS SUPER TIGRE mufflers available hobby shop ORDER DIRECT immediate shipment Check MO Visa MC CODSEND 25r STAMP accepted Add $250 UPS $205 tsr COD 6% sales taxFOR ADDITIONAL INFO Calif residentAND JTEC CATALOG January 1989 43 qqFP PUT YOURSELF AT ThE CONTROLS OF PROVEN GREAT FLYING WARDIRD almost ready fly kits have wing loadings lighter trainers very docile air land like Cub building-to-flying time very minimal fine kits together skill imagination will make plane crowd pleaser field Retracts now available Strong Light Reliable Pneumatics Idts come furnished fiberglass cowls WrIte call D&R Aircraft Mfg RO Box 23056 in TX 78736 512/288-2055 512/672-7023 Dealer Inquiries Invited $24 95 CAT NO 800 S Balsa0 Cutter5 T001~ 5 pc Masters Set 1/8 3/16 1/4 5/16 3/8 . $1698 3 pc Builders Set 3/161/4 5/16$998 Whether YOU kit builder scratch builder SQUARE CUT Tools will save time Remove stubborn die cuts cut own squares slots Made US quality machined zinc plated steel Order set today See Dealer Cataloger Order dont carry Square Cut Tools call us call well pay shipping SQUARE CUT Tools 4073 254-0516 905 N Harbor City Blvd Melbourne FL 32935 Florida Residents Dealer Distributor Inquiries Invitedadd 6% mien tax yr American Eaglet - was first light-plane receive type certificate Anorioan Eaglet carry two ooersdby LTMJ 05 motorpeople 45 horsepower ohkheosorv-Packooedintoisuros-The Eaglet complete itight system idOSA 1930s contemporary Aeronca C3 Taylor Cubs Health Parasol Pietenpol Air Camper Eaglets gentle flying characteristics reason flying schools day chose standard instructional aircraft Leisures easy-to-build scale model kit Amencan Eaglet 05 electric powered shares gentle Keiths flight itsomething hed wanted 1985 couldnt because Teds preemptive action Anyway seeing oles own design being flown Master happy humbling experience very much enjoyed particular flight Keith routinely flies oth ers models asked OK Mitch Maybe will publish Would like kit Ted sad thing about KRC meet ends good thing have en joyed continuance others hard imagine next year will mark 10th anniversary KRC Electric Fly What began dubious risky one-day affair 1980 tracted three icipants has matured two annual days sheer joy excitement happiness two days re charging friendships associations made past two days new memories ac quaintances formed year two days Electric advancement achievement shared displayed allwith having come mean over 100 participants hundreds spec tators Its heckofa flight folks have comments youd like share other Electrickers Please send themor questions SASE please ad dress given box very beginning column sincere thanks numerous folks came Fly comment favorably column appreciate interest feel ing taking time say flight characteristics full scale aircraft Scaled 18 inches-to-foot model features span 62 inches wing area 571 square inches Its lightweight structure 4041 oz flying weight allows low wing loading 104 ounces per square foot combined Leisure flight system turning 11 x 5 prop flight performance spectacular Takeoff occurs after 20 foot ground roll climb-out brisk model has thermaled moderate lift conditions Gentle landings breeze Scale details documentation included plans make scale contest winner Rsr afree copy Leisures new full color catalog send stamped self addressed business sized envelope Leisure Electrenics Inc 22971 Triton Way Unit B Lesguna Hills C4 92653 RC AerobaticsNan Putte Continued page 43 must able trimned must sta ble airplane trimmed steady level flight forces moments acting must add up zero means lift equals weight thrust equal drag no net pitching moment present two curves referred lift pitching moment curves Figure 1 shows rela tionship between lift generated given speed aircraft angle attack can see theres angle attack lift equals airplane weight airplane must angle attack maintain unaccelerated level flight airspeed chosen exam ple called trim angle attack Theres different trim angle attack another airspeed airplane angle attack higher trim angle attack will tend climb vice versa second Figure 2 curve really set curves shows pitching moment generated stable airplane given speed function airplane angle attack several elevator set tings pitching moment muat zero trim curve can pass through zero pitching moment aircrafts trim angle tack lift equals airplane weight curve labeled E2 corresponds particular elevator position summarize given airspeed angle attack elevator setting airplane will maintain unaccelerated level flight change throttle setting consume fuel trim attitude airplane will change elevator deflection required Leisure achieve will change well have prob ably noted airplanes trim changes fuel consumed flight speed changed Airplanes can designed minimize ef fects will always present degree Now what about William Ropers problem take airplane steady level flight roll 90 roll performed almost about axis line direction airplane flying call rolling about velocity vector airplane rolled 900 about axis lift wing does change However now lift countering airplanes weight fact its pointed perpen dicular Newtons laws obviously work situation airplane accelerates direction perpendicular wings downward well So much mystery What happens airplane rolled less 45 ally same forces present airplane rolled 90 effect reduced Consequently air plane will start gentle turn due unopposed part lift generated wing airplanes descent reduced because substan tial fraction lift available counter airplanes weight Consequently airplane will enter descending torn So does banking produce heading change Yes suggestion made William Roper way oppose heading change rolling maneuver judicious use rudder What suggested true However dont know anyone fast enough right amount rudder counter heading changes good news takes time airplanes heading change very much since supposed perform three rolls five seconds heading changes dont have January 1989 159 New Leisure introduces electric scale American Eaglet responding advertisers mention thatyou read about ModelAviation lot time develop allegation nobody does axial roll true lift force being developed wings rotates around airplane rolls air plane accelerates direction unop posed force means path air plane cannot straight Obviously some air planes better others performing axial rolls barrel roll degree RC Slope Soaring/Triebes Continued page 45 ships Can imagine what would say someone claimed powered plane fully acrobatic asymmetrical wing no rud der same goes Slope Soarers snap rolls four-point rolls clean hammerheads other maneuvers must have rudder side outside maneuvers have same size shape symmetrical alrfoil pretty much necessity almost no Slope kits fully acrobatic writers like yourself keep sisting todays crop planes like Savage its progeny SR-7 forth good are fully aerobatic think will see new breed Another thing will further good designs contests CD thinks nothing call ing outside loops inverted flight rolling circles one-and-a-half snaps vertical eights Jef makes some very good points am sure Slope Soaring continues grow MINI-JET SERIES planes feature balsa construction Designed intermediate flyer in A4 mind will accept 20-25 size engine fuse rear exhaust engine exceptional Skyhawk performancel thrill jet heesles ducted fan $4000 &H Proud Bird deeignad meet OSPRA Formula 120 rules 114 scale model will accept 60-120 ci size engines Epoxy glees fueelage foam wing construction Full kit $150 Semi-kit also available Inn woodi $i25 Please add $10 S&H F-20 Tlgenhark Send check money order COD add $300 esidents add 6% sales tsx Dart ExperImental two-place full size alrr5ft Top Turkey Formula 1 $85$5S&H PARRISH AIRCRAFTScale Models ll25SW49thTer Plantation FL33317 will see new designs emerging number hoped will fully acrobatic Jef also looking some information help him evaluate relative merits different sym metrical airfoils Slope Soaring Aerobatics Any information can get subject would greatly appreciated Jefs name sounds familiar some probably because principal people involved developing Apple Macin tosh computer Jef also wrote program Micro soft Basic Mac will calculate coordi nates display picture NACA fourdigit airfoil appears Martin Hollmanns book Modem Aircraft Design very inter esting us designer types play would like listing program send SASE two stamps please Spitfire Slope LeRoy Satterlee Wa terloo IA sent couple photos beautiful Spitfire Mk XII built John Lupperger Plans Service plans what has say about designed 25-size power plane orig inally did build light leave off engine finished plane flown aile ron elevator no rudder wing loading 925 oz per sq ft made slow est flying Spitfire anyone could remember having seen addition about 10 oz lead picked up flying speed plane flew much solidly experiments will continue re turn hill later year ever build another Spitfire Ill build heavier use thin ner airfoil some kind get speed up further Power Slope Scale fun di version recommend everyone LeRoy flying buddies travel two-and-ahalf hours southeastern Wisconsin Slope flying sald Slope fliers dedi cated Four group including LeRoy have completed LSF Level 5 eight-hour slope flights Superslope Tom Rent member fleer Minnesota RC Soaring Society gives further evidence Slope Soaring alive well Midwest club relatively large approaching 100 members have recently discovered 160 Model Aviation CA MASK CA glue works wonders building models right Unfortunately gives enough fumes knock vulture off carcass modelers have suffered medical problems after inhaling CA fumes take chances special vapor respirator filters CA fumesl soft face mask adjustable straps comfortably fits face sizes easy breathing valve allows prolonged use providing dependable filtering concentrations up 1000 PPM though rugged industrial mask light weight elimi nate fatigue Dont get gassed CA Get protected Order CA Mask today Just $1247 shipping cheaper hospital visit Money order Master Charge Visa include expiration date check allow 20 days clear Sorry no CODs Pelican Enterprises 2540 RIDGE ROAD LANSING ILLINOIS 60438 P S Send catalog modelers safety supplies 305 581-4477 Latest Japanese Pattern Design Designed & Flown TOP Japanese Pilot Suitable FAI AMA Classes tCa5a FberRedewd EtrexyiSasa FuaabgaSpa, -57 wing Area 750 eq 2 Fe 5e Siesied Cake FbarRakfrexedUkeLld HxeepaenA PraitWhrs 3Fadxy5traahd a5patle& raesrieeke 41W errewarhised hedre ed 5 Pawt FeaeI Now Offered Super Deluxe Pm-Built Kit $45000 Completely Finished Model Call info & pricing VISA& MASTERCARD WELCOME Pteae add $t5mt Srr& Hadna inidaadd &5%.15550dntwa&AdaCewayNPhone408298-0311 FAX#408298-6538 IA NEW ELECTRIC Fly .. great stand-way-off scale fun ship designed 05 electric power can perform take-offs touch goes aerobatics beauty yet enjoy docile slow flight easy landings Quick easy build kit includes pre cut fuselage sides tail feathers small parts hardware complete rolled plans step-by-step instructions formed landing gear windshield Electro-Combo includes kit DSC 075 Hyperthrust motor fused switch harness Tamiya connector propeller adaptor 8/4 fiberglass propeller 40 Span 275 Sq area 32 oz flying weight flat bottom airfoil rudder elevator motor add ailerons too SPECIAL COMBO PRICE $4795 IPAVEY675 YSTEMSWEST CHESTEF PA 193& BASIC KIT $244oRRATloN215~ wonderful world Slope Soaring Although true Midwest flat some areas blessed beautiftil grass-covered hills provided retreating glaciers site Superslope call Nerstrand MN perfect come Picture Steep grass-covered face road parking area top wide face no trees unobstructed flatlands below smooth airflow remote location no houses traffic its 30-to-40-minute drive Twin Cities Rochester am continually surprised number Slope fliers located Midwest Slope Soaring has long considered coastal sport caters mainly California crowd rapidly gaining reputation universal branch Soaring Beginner hints letters receive fliers new Slope Soaring ask ing few hints finding good site mak ing first flight help position also remind us little experienced basics Slope fly ing Finding good site really too difficult principle reality may turn out some what harder depending location ex perience ideal slope site would range foothills unobstructed face no trees bushes etc looks prevailing winds Actual size hill really important have flown off 5000-ft peaks off 10ft ridges What important find site faces steady relatively strong 10-30 mph winds will want find hill ridge has clear unobstructed top land ing easiest general really need take Sailplane will fly light conditions day conditions such go out vestigate possible sites cannot really de termine anything about quality site until have flown off Some best sites look nearly good vice versa As flying itself let offer couple comments should get through begin ning stages First predominant lift slope generated area about 450 top hill angle going wind commonly used technique fly back forth across face hill remaining 450 column air really difficult might sound simply location best lift reality lift just about everywhere windward side hill important thing remember get behind hill rotors develop downwind side hill have destroyed Sailplanes characteristic Slope Soaring probably difficult begin ners overcome simplest way keep out trouble imagine wall extends along top hill ridge must remain front wall stay clean air avoid downdrafts other side Once have few hours experience Slope flying will able investigate area tually youll able use advantage landing beginner place stay clear As launching will want take few steps down face hill avoid having plane thrown back behind hill Simply give plane good toss straight wind continue fly straight out until stronger lift Landing quite simple launching still difficult As beginner will probably want land going across face hill simplest surest way getting down getting caught behind hill stalling plane trying slow down too much Just fly plane slowly possible across face slightly below top hill continue lower lower until can land certainly neither pretti est nor purist way land its effective somewhat easier beginner Once have little experience will able use rotors behind hill re duced lift top hill simply lower plane down land top would rec ommend method until have logged few hours comfortable flying slope After said done best way learn fly slope simply probably saying yourself easy say being experienced Sloper just beginner beginners time us learned fly slope just doing methods beginning Sloping have helped people get sport am sure other hints could helpful neophyte know anything think might help someone little no experience slope let know will pass Slope types Another frequently asked question receive just shape slope af fects lift produced slope best way analyze lift site analyze cross sec tion slope specifically angle slope As general rule gentler slope say 300 will produce lighter lift over large area steeper slope approaching January 1989 161 Leo & MODEL BUILDING 7SERVICE RADIO CONTROL FROVUCTS carry full line Byron Originals Bob Parkerson Tom Cook Bob Violet products COD Orders Accepted 718 983-9735 128 WATCHOGUE ROAD EN SlAM 0314 Electric F ight Has Brake Lightweight 12 OLmosey hark Adjustable switching poiut guarantee easy hookup $249 ON/OFF Controller5 Power save weight aiZO Size 22x13x63 Very high efficiency 006' loss Add $105 shippiog Colitorojarosideots add 65% $163 Tss Send Check money order CoasesoithiiHIgh Sky Falaha sonsector Kansas St #9 otEaeeSan DiegoCA 92104 vertical will produce stronger lift over consider ably smaller area other words lift area slope directly related steepness slope wish fly stronger lift use up rel atively little available sky will want fly off cliff similar type slope would rather fly lighter consist ent lift will probably want fly slope quite steep Demon Tweaks have passed around modeling community some time Although theyre aimed specifically Slope Soar er hints trimming out Sailplane can immeasurable help give credit credit due believe Tweaks origi nated Pikes Peak Soaring Society newslet ter Spoiler specifically its edi tor Randy Reynolds Demon Tweak #1Make sure flying sur faces straight can done variety ways favorite simply sight down bottom surface wings stabs rear airplane suspicious surface can dis mounted double-checked flat surface such workbench flat right Trailing edges can sighted down similar manner check trueness particularly critical stab/elevator surfaces Demon Tweak #2It less fashionable days employ washout wing tips Washout trailing edge higher leading edge theory smaller chord tip would stall earlier root thus causing falloff tip another recommendation use washout since difference degree will cause erratic flightpath higher speeds such launch can check models tendency tip stall flight slowly bringing nose up until Glider stalls recovers straight ahead have washout bird good shape Demon Tweak #3Set up center-ofgravity properly Often kit plans call balanc ing spar frequently extremely conservative location will yield excellent sta bility very mediocre performance just learning fly leave ready handle performance should learn measure CG percentage wing chord able relate field experi ences percentage shop has two large blocks spruce tri angular pieces positioned halfway down block determine CG place assembled Glider triangular stock pieces un der wing root Balance Glider fore aft Measure distance triangular piece leading edge calculate per centage against full chord Generally speak ing trainers set up 30-33% Most higher-performance ships happiest 3538% Eppler 205 ships perform best 38% according pilots Use own judg ment wouldnt exceed 37% flatbottom airfoiled ships unless Top Gun caliber Demon Tweak #4Many entry-level ships observed climbing out launch shallow angles yield poor altitude Again kit manu facturers want safe suecessful therefore towhook positions extreme ward Once have learned fundamentals flying time tune towhook position CG Please think two factors insep arable generally place towhook exactly un der CG have always reliable high launches Most fliers position hook somewhat forward location perhaps / aggressive fliers looking maximum alti tude actually place hook behind CG What ever make changes several small steps starting hook ahead CG lo cation Authors note demon tweak obvi ously does apply Slope Soaring al though probably don' like admit some us occasionally some thermal flying Demon Tweak #5Most entry-level ships have narrow speed range would benefit installation turbulator strips devices tend reduce airflow separation top sur face improve performance during slow flight Studies have seen recommend two strips 10% chord measuring leading edge other 20-25% make turbulator strips Goldberg /32 color striping tape Typ ically strip laid directly top another yield bump thats repositionable decora tive tinkerers delight Bump Soaring What world Bump Soar ing Essentially Slope soaring slope thought needed large hill mountain range provide lift needed fly wrong needed create rising air enables Slope ships stay aloft something deflect change direction wind Thus need Bump Soar small ridge bump will deflect wind up wards some relatively strong winds have flown ridges small five six feet high have produced consistent lift winds 25-to-30 mph range lift does extend upwards very high strong enough maintain 25 50 ft altitude work ridge back forth What Bump Soaring does provide Slope flier opportunity polish skills learn mechanics Slope flying What type Sailplane need get volved Bump Soaring Unfortunately high-performance Racing ships just will able find lift needed unless happen flying hurricane-force winds type Sailplane best suited Bump Soaring light weight hand-launch type plane Most lighter thermal ships will able fly kind lift smaller plane better will able manage small lift area tight turns associated Bump Soaring would like try exciting diversion everyday Slope flying give Bump Soaring try very fun exhilarating way polish flying skills have opportunity travel favorite slope slope sites wanted Thanks High Performance Models presents ECL IPSE Designed Henry Piorun Former Canadian National Champion & FAI Canadian Team Member Designed Specifically FAI Pattern Flying Perform Equally Well Other AMA Classes Plug Wings rglass Belly Pan Pre-Cut Moles br Wing Joiner Tubes Ultralight Honeycomb Wingoores xfra404601 Optional Plastic Fiberglass Canopy Fiberglass Fuselage molded wing Joiner tube HIGH PERFORMANCE MODELS 9556116 st North Delta British Columbia 6Z4 Canada 604-588-0605 FINALLY Ultimate BOARD Designed & engineered WARP FREE construction HIGH-TECH MATERIAL Portable Ughtweight Conveniently Stored Large 20x78 Endgrain balsa block pin surface 314 deep Unaffected temperature humidity CASH PRICE $1 3500 Cai UPS VBA & MC 3700 BOULDER PORT ARTHUR TX 17640 409-982-8717 -F-who have sent details about favorite fly ing sites Although have received information number sites would really like have quite few put together really thorough complete directory slope sites send information favorite site please include such things prevailing winds slope gle landing area characteristics quality lift recommended flying experience directions and/or map local contact possible photo site Thanks again help project RC Scale/SruII Continued page 47 lected subtle shading keyword subtle Dont panels dont overdo Two colors will required high lights shadows Using basic air craft finish color add little white high light color little black shadow color Experiment first some scrap paper before tacking model Spray shadows first add highlights Remember Go easy dont overdo other method requires model sub structure supporting skin less scale model covered skinned somewhat flexible material does tally hide supporting substructure Major bulkheads stringers ribs spars model should located scale positions wherever pos sible Its usually good idea follow fullscale prototype structural layout anyhow scratch-building model rather totally re engineer perfectly good full-scale airplane de sign Rather using relatively stiff balsa skin typical balsa stock would firm %2 sheet plank model want use strong flexible covering material skin should flex distort small amount make internal structure visiblelike prototype Zero starved horse look usually work hard avoid just thing trying achieve case two materials have experience job nicely / ply /~ balsa / ply has very good tensile strength plus some flexibility best suited larger Scale models easiest use large pieces surfaces devoid compound curves such wing skins /16 firm balsa covering well-sanded %2 soft balsa well suited small-to-moderatesize models %- A-scale easy apply compound- high-curvature surfaces Being flexible will tend sag ripple /64 ply So depending scale model local skin strength required choose whichever best suits need case balsa skin will require layer lightweight glass cloth after attached framework will provide needed strength balsa well making surface hard enough finish standard practice edgegluing balsa sheets sanding smooth finish before attaching framework applies thin-skin structure used fi nal touch panel ripple should applied airbrush authentic look Now lets hear wrinkied-skin Zeros about target tow option least-seen interesting flight options suit able number Scale aircraft subjects target tow military training aircraft dating back Thirties pressed ser vice during WV II tow various flag sleeve targets use ground-to-air air-to-air gun nery practice An example Dreadnought version British Hawker Sea Fury fighter shown page 92 November 1988 issue MA nice plus target-tow airplanes sport interestlng distinctiveif garish color schemes ideal Scale model use sim ple reason bright color schemes flight crews wanted make absolutely sure tow aircraft could clearly seen dis tinguishable target sleeve nearsighted rookie gunnery student Though very interesting target tow simpler flight options Properly done INTRODUCING THE ELE7/JL/FE FOR 020-035-050 ELECTRICI\r SPAN 36 AREA 25T CHANNELS 2-3 ONOTH 3T FLYING WY 20 TO 30 OZ Designed built EIecSrlo Model Co 218 Oyster Ck r Land TX 77478 242-6229 Souths ingest inventory satro motors & accessories Need help wIth yow electdc ahplm orglder Ask Doe j~DuaIStrut Nose Gear Fults Tooling PO Box 95 Champaign IL 61820 NumberflistanReCe SF350 5 95 SF400 6 95 SF500 32 66901695 RF500 32 96-121595 RFY5T 321 SCSI1565 AAIosIabRGuadla OFROTlAs3116 1 seal 2995 PRODUCTS FOR THE DISCERNING MODELER Complete Line Exhaust Systems * Tuned led Tuned Pipes Headers uri Mufflers * Expansion Mufflers copter Ball Mufflers * Specialized Exhaust Systems Unsurpassed January 1989 163 Yes Virginia Santa Claus 2z Get Nearest Santas Shop 5sPeopIeof Com6ddem /mkc74 Aec Instantly removable sri-cycle gear wheels Pre-built boom landing gear sockets 8 push-roth Astro motor mount cobalt adapter Preformed leading edges knotched trailing edges Air frame 6 oz 75 ox landing gear Perfect performance 02003535 systems Maximum duration 8 glider-like motor-ofi flight characteristics ARF build 8 cover wing also completely built tail surfaces hinged . $7996 w/o gear $8695 gear ladd $3 eftipping TX res add 6% sales taxi
Edition: Model Aviation - 1989/01
Page Numbers: 42, 43, 159, 160, 161, 162, 163
QUESTIONS often appear letters arrive mail box following letter addressed Model Aviation forwarded pub lisher may concern ve flying RC planes about 4/2 years now started Goldberg Eagle 63 Over time able perform various stunts such loops barrel rolls inverted flight touch-and-go etc recently purchased built Goldberg Sky Tiger problem cant get plane turn rudder left right use rudder plane does flat turn cant get plane bank unless use ailerons banldng try level plane out rudder acts its sideslipping Say Im banking right give left rudder roll out bank Instead plane rolling left level flight plane stays bank nose goes up doing sideways flat turn tends cause loss altitude cant life figure problem out control throws set according instructions now need some experi enced advice correcting matter plane flies well except fact cant use rudder turn letter signed John Fleming Vernon NY wrote letter John rea lized problem might shared number fliers hadnt written letters Model Aviation seeking help information Its easy understand lack rolling response rudder control input would cause pilot accustomed beginner-type aircraft think problem perhaps ginner aircraft intentionally have too much dihe dral wing Consequently rudder deflected airplane starts sideslip dihedral wing generates rolling moment airplane banks direction rudder deflected So pilot thinks rudder caused bank Well suppose rudder did cause bank couldnt have happened wing dihedral So have two ways bank airplane rudder ailerons Thats good Right really Using rudder bank air plane fine long dont want turn airplane beginner airplanes dont have ailerons perform missions very well rather abrupt turns performed using rudder/wing dihedral banldng mechanism its hard tell Lift Airplane Weight Angle Attack atrim Figure 1 Ron discusses stability trim answers questions about Pattern models seemingly inexplicable things sometimes figure porlrays unique wing angle tack s needed sustain airplane level unaccelerated flight particular airspeed turns arent being done using ailerons However reason using rudder bank airplane satisfactory beginners dont tend fly airplanes inverted per form maneuvers like knife-edge flight point rolls want progress flying advanced ma neuvers must have airplane does bank rudder deflected roll airplane knife-edge apply top rud der keep nose up dont want wing dihedral cause airplane roll So benchmarks airplane Pattern flying potential absence rolling ten dency rudder deflected goal learn fly Pattern ma neuvers can bank airplane rudder reduce wing dihedral until doesnt What did tell John Fleming Sky Tiger doing just what its supposed Dont change anything Another letter arrived Wil liam Roper Englewood CO wrote long Pitching Moment Angle Attack atrim E3 Figure 2 series curves illustrtates pitching moments generated stable air plane constant airspeed several different elevator deflections E1 E2 E2 order trim plane unique elevator deflection generating zero pitching moment trim angle attack attm found Figure 1 necessary Only elevator deflectIon satisfies things 42 Model Aviation Radio Cono Sport Aerobatics Ron Van Putte Ill Sleepy Oaks Rd Ft Walton Beach FL 32548 happens pros AMA President Don Lowe examines spot cov ering missing wing Phoe nix 9 sure makes funny sound de parts during flight letter suppositions questions Wont quote whole letter just part along responses William started out like What Im trying sort out straight level unaccelerated flight Pattern airplane slowly rolled 900 either direction no other input applied airplane Im working now maintains altitude some dis tance heading changes toward direc tion roll ie pulls toward canopy RVP Obviously aircraft starts approach terra firma bank angle exceeds 450 noth ing oppose gravityno lift up about 450 bank aircraft starts almost circle since normal aircraft center-ofgravity must forward center-of-pressure some amount lest aircraft fall stall tail first circling tendency should ev ident Pattern aircraft some degree other Put another way Pattern aircraft trimmed straight unaccelerated flight will fly both upright inverted altitude change banking wings either upright inverted will produce heading change True way oppose heading change Pattern aircraft rolling maneuver judicious use rudder Which would also mean no such thing axial roll well-trimmed Pattern airplane barrel rolls altitude heading ex cursions too small detect True questions hit heart air planes really fly what differences tween trim stability Let clear air state impossible have airplane has trimmed straight level un accelerated flight rolled inverted have maintain altitude unless several complicated inter actions between engine wings fiAselage horizontal tail just right consider interaction just wings horizontal tail impossible no matter what Thats see few examples airplanes can trim just once both upright inverted flight mechanics level flight simple ten misunderstood shade tree aerody nainicists Im going bore Out skull lot equations just two simple curves will suffice get points across successful flying airplane Continued page 159 SAVE YOUR FIELD SNuF-LER muffler low cost easy install lightweight sound reducing muffler no performance penalty answer AMA muffler rule suggestions saving flying fields Meets AMA muffler rule suggestionsSNUF-LER 3 10 decIbels quieter stock mufflerMUFFLER No power loss possible 300-500 RPM increase Pat Pending Improves engine idle s better fuel economy Easily attached 25-108 stock mufflers Heat corrosion resistant Black E coat finish No special adapters required Weighs 35 oza Fits ASP BRAT ENYA FOX HP IRVINE K & B OS MAX ROYAL YS SUPER TIGRE mufflers available hobby shop ORDER DIRECT immediate shipment Check MO Visa MC CODSEND 25r STAMP accepted Add $250 UPS $205 tsr COD 6% sales taxFOR ADDITIONAL INFO Calif residentAND JTEC CATALOG January 1989 43 qqFP PUT YOURSELF AT ThE CONTROLS OF PROVEN GREAT FLYING WARDIRD almost ready fly kits have wing loadings lighter trainers very docile air land like Cub building-to-flying time very minimal fine kits together skill imagination will make plane crowd pleaser field Retracts now available Strong Light Reliable Pneumatics Idts come furnished fiberglass cowls WrIte call D&R Aircraft Mfg RO Box 23056 in TX 78736 512/288-2055 512/672-7023 Dealer Inquiries Invited $24 95 CAT NO 800 S Balsa0 Cutter5 T001~ 5 pc Masters Set 1/8 3/16 1/4 5/16 3/8 . $1698 3 pc Builders Set 3/161/4 5/16$998 Whether YOU kit builder scratch builder SQUARE CUT Tools will save time Remove stubborn die cuts cut own squares slots Made US quality machined zinc plated steel Order set today See Dealer Cataloger Order dont carry Square Cut Tools call us call well pay shipping SQUARE CUT Tools 4073 254-0516 905 N Harbor City Blvd Melbourne FL 32935 Florida Residents Dealer Distributor Inquiries Invitedadd 6% mien tax yr American Eaglet - was first light-plane receive type certificate Anorioan Eaglet carry two ooersdby LTMJ 05 motorpeople 45 horsepower ohkheosorv-Packooedintoisuros-The Eaglet complete itight system idOSA 1930s contemporary Aeronca C3 Taylor Cubs Health Parasol Pietenpol Air Camper Eaglets gentle flying characteristics reason flying schools day chose standard instructional aircraft Leisures easy-to-build scale model kit Amencan Eaglet 05 electric powered shares gentle Keiths flight itsomething hed wanted 1985 couldnt because Teds preemptive action Anyway seeing oles own design being flown Master happy humbling experience very much enjoyed particular flight Keith routinely flies oth ers models asked OK Mitch Maybe will publish Would like kit Ted sad thing about KRC meet ends good thing have en joyed continuance others hard imagine next year will mark 10th anniversary KRC Electric Fly What began dubious risky one-day affair 1980 tracted three icipants has matured two annual days sheer joy excitement happiness two days re charging friendships associations made past two days new memories ac quaintances formed year two days Electric advancement achievement shared displayed allwith having come mean over 100 participants hundreds spec tators Its heckofa flight folks have comments youd like share other Electrickers Please send themor questions SASE please ad dress given box very beginning column sincere thanks numerous folks came Fly comment favorably column appreciate interest feel ing taking time say flight characteristics full scale aircraft Scaled 18 inches-to-foot model features span 62 inches wing area 571 square inches Its lightweight structure 4041 oz flying weight allows low wing loading 104 ounces per square foot combined Leisure flight system turning 11 x 5 prop flight performance spectacular Takeoff occurs after 20 foot ground roll climb-out brisk model has thermaled moderate lift conditions Gentle landings breeze Scale details documentation included plans make scale contest winner Rsr afree copy Leisures new full color catalog send stamped self addressed business sized envelope Leisure Electrenics Inc 22971 Triton Way Unit B Lesguna Hills C4 92653 RC AerobaticsNan Putte Continued page 43 must able trimned must sta ble airplane trimmed steady level flight forces moments acting must add up zero means lift equals weight thrust equal drag no net pitching moment present two curves referred lift pitching moment curves Figure 1 shows rela tionship between lift generated given speed aircraft angle attack can see theres angle attack lift equals airplane weight airplane must angle attack maintain unaccelerated level flight airspeed chosen exam ple called trim angle attack Theres different trim angle attack another airspeed airplane angle attack higher trim angle attack will tend climb vice versa second Figure 2 curve really set curves shows pitching moment generated stable airplane given speed function airplane angle attack several elevator set tings pitching moment muat zero trim curve can pass through zero pitching moment aircrafts trim angle tack lift equals airplane weight curve labeled E2 corresponds particular elevator position summarize given airspeed angle attack elevator setting airplane will maintain unaccelerated level flight change throttle setting consume fuel trim attitude airplane will change elevator deflection required Leisure achieve will change well have prob ably noted airplanes trim changes fuel consumed flight speed changed Airplanes can designed minimize ef fects will always present degree Now what about William Ropers problem take airplane steady level flight roll 90 roll performed almost about axis line direction airplane flying call rolling about velocity vector airplane rolled 900 about axis lift wing does change However now lift countering airplanes weight fact its pointed perpen dicular Newtons laws obviously work situation airplane accelerates direction perpendicular wings downward well So much mystery What happens airplane rolled less 45 ally same forces present airplane rolled 90 effect reduced Consequently air plane will start gentle turn due unopposed part lift generated wing airplanes descent reduced because substan tial fraction lift available counter airplanes weight Consequently airplane will enter descending torn So does banking produce heading change Yes suggestion made William Roper way oppose heading change rolling maneuver judicious use rudder What suggested true However dont know anyone fast enough right amount rudder counter heading changes good news takes time airplanes heading change very much since supposed perform three rolls five seconds heading changes dont have January 1989 159 New Leisure introduces electric scale American Eaglet responding advertisers mention thatyou read about ModelAviation lot time develop allegation nobody does axial roll true lift force being developed wings rotates around airplane rolls air plane accelerates direction unop posed force means path air plane cannot straight Obviously some air planes better others performing axial rolls barrel roll degree RC Slope Soaring/Triebes Continued page 45 ships Can imagine what would say someone claimed powered plane fully acrobatic asymmetrical wing no rud der same goes Slope Soarers snap rolls four-point rolls clean hammerheads other maneuvers must have rudder side outside maneuvers have same size shape symmetrical alrfoil pretty much necessity almost no Slope kits fully acrobatic writers like yourself keep sisting todays crop planes like Savage its progeny SR-7 forth good are fully aerobatic think will see new breed Another thing will further good designs contests CD thinks nothing call ing outside loops inverted flight rolling circles one-and-a-half snaps vertical eights Jef makes some very good points am sure Slope Soaring continues grow MINI-JET SERIES planes feature balsa construction Designed intermediate flyer in A4 mind will accept 20-25 size engine fuse rear exhaust engine exceptional Skyhawk performancel thrill jet heesles ducted fan $4000 &H Proud Bird deeignad meet OSPRA Formula 120 rules 114 scale model will accept 60-120 ci size engines Epoxy glees fueelage foam wing construction Full kit $150 Semi-kit also available Inn woodi $i25 Please add $10 S&H F-20 Tlgenhark Send check money order COD add $300 esidents add 6% sales tsx Dart ExperImental two-place full size alrr5ft Top Turkey Formula 1 $85$5S&H PARRISH AIRCRAFTScale Models ll25SW49thTer Plantation FL33317 will see new designs emerging number hoped will fully acrobatic Jef also looking some information help him evaluate relative merits different sym metrical airfoils Slope Soaring Aerobatics Any information can get subject would greatly appreciated Jefs name sounds familiar some probably because principal people involved developing Apple Macin tosh computer Jef also wrote program Micro soft Basic Mac will calculate coordi nates display picture NACA fourdigit airfoil appears Martin Hollmanns book Modem Aircraft Design very inter esting us designer types play would like listing program send SASE two stamps please Spitfire Slope LeRoy Satterlee Wa terloo IA sent couple photos beautiful Spitfire Mk XII built John Lupperger Plans Service plans what has say about designed 25-size power plane orig inally did build light leave off engine finished plane flown aile ron elevator no rudder wing loading 925 oz per sq ft made slow est flying Spitfire anyone could remember having seen addition about 10 oz lead picked up flying speed plane flew much solidly experiments will continue re turn hill later year ever build another Spitfire Ill build heavier use thin ner airfoil some kind get speed up further Power Slope Scale fun di version recommend everyone LeRoy flying buddies travel two-and-ahalf hours southeastern Wisconsin Slope flying sald Slope fliers dedi cated Four group including LeRoy have completed LSF Level 5 eight-hour slope flights Superslope Tom Rent member fleer Minnesota RC Soaring Society gives further evidence Slope Soaring alive well Midwest club relatively large approaching 100 members have recently discovered 160 Model Aviation CA MASK CA glue works wonders building models right Unfortunately gives enough fumes knock vulture off carcass modelers have suffered medical problems after inhaling CA fumes take chances special vapor respirator filters CA fumesl soft face mask adjustable straps comfortably fits face sizes easy breathing valve allows prolonged use providing dependable filtering concentrations up 1000 PPM though rugged industrial mask light weight elimi nate fatigue Dont get gassed CA Get protected Order CA Mask today Just $1247 shipping cheaper hospital visit Money order Master Charge Visa include expiration date check allow 20 days clear Sorry no CODs Pelican Enterprises 2540 RIDGE ROAD LANSING ILLINOIS 60438 P S Send catalog modelers safety supplies 305 581-4477 Latest Japanese Pattern Design Designed & Flown TOP Japanese Pilot Suitable FAI AMA Classes tCa5a FberRedewd EtrexyiSasa FuaabgaSpa, -57 wing Area 750 eq 2 Fe 5e Siesied Cake FbarRakfrexedUkeLld HxeepaenA PraitWhrs 3Fadxy5traahd a5patle& raesrieeke 41W errewarhised hedre ed 5 Pawt FeaeI Now Offered Super Deluxe Pm-Built Kit $45000 Completely Finished Model Call info & pricing VISA& MASTERCARD WELCOME Pteae add $t5mt Srr& Hadna inidaadd &5%.15550dntwa&AdaCewayNPhone408298-0311 FAX#408298-6538 IA NEW ELECTRIC Fly .. great stand-way-off scale fun ship designed 05 electric power can perform take-offs touch goes aerobatics beauty yet enjoy docile slow flight easy landings Quick easy build kit includes pre cut fuselage sides tail feathers small parts hardware complete rolled plans step-by-step instructions formed landing gear windshield Electro-Combo includes kit DSC 075 Hyperthrust motor fused switch harness Tamiya connector propeller adaptor 8/4 fiberglass propeller 40 Span 275 Sq area 32 oz flying weight flat bottom airfoil rudder elevator motor add ailerons too SPECIAL COMBO PRICE $4795 IPAVEY675 YSTEMSWEST CHESTEF PA 193& BASIC KIT $244oRRATloN215~ wonderful world Slope Soaring Although true Midwest flat some areas blessed beautiftil grass-covered hills provided retreating glaciers site Superslope call Nerstrand MN perfect come Picture Steep grass-covered face road parking area top wide face no trees unobstructed flatlands below smooth airflow remote location no houses traffic its 30-to-40-minute drive Twin Cities Rochester am continually surprised number Slope fliers located Midwest Slope Soaring has long considered coastal sport caters mainly California crowd rapidly gaining reputation universal branch Soaring Beginner hints letters receive fliers new Slope Soaring ask ing few hints finding good site mak ing first flight help position also remind us little experienced basics Slope fly ing Finding good site really too difficult principle reality may turn out some what harder depending location ex perience ideal slope site would range foothills unobstructed face no trees bushes etc looks prevailing winds Actual size hill really important have flown off 5000-ft peaks off 10ft ridges What important find site faces steady relatively strong 10-30 mph winds will want find hill ridge has clear unobstructed top land ing easiest general really need take Sailplane will fly light conditions day conditions such go out vestigate possible sites cannot really de termine anything about quality site until have flown off Some best sites look nearly good vice versa As flying itself let offer couple comments should get through begin ning stages First predominant lift slope generated area about 450 top hill angle going wind commonly used technique fly back forth across face hill remaining 450 column air really difficult might sound simply location best lift reality lift just about everywhere windward side hill important thing remember get behind hill rotors develop downwind side hill have destroyed Sailplanes characteristic Slope Soaring probably difficult begin ners overcome simplest way keep out trouble imagine wall extends along top hill ridge must remain front wall stay clean air avoid downdrafts other side Once have few hours experience Slope flying will able investigate area tually youll able use advantage landing beginner place stay clear As launching will want take few steps down face hill avoid having plane thrown back behind hill Simply give plane good toss straight wind continue fly straight out until stronger lift Landing quite simple launching still difficult As beginner will probably want land going across face hill simplest surest way getting down getting caught behind hill stalling plane trying slow down too much Just fly plane slowly possible across face slightly below top hill continue lower lower until can land certainly neither pretti est nor purist way land its effective somewhat easier beginner Once have little experience will able use rotors behind hill re duced lift top hill simply lower plane down land top would rec ommend method until have logged few hours comfortable flying slope After said done best way learn fly slope simply probably saying yourself easy say being experienced Sloper just beginner beginners time us learned fly slope just doing methods beginning Sloping have helped people get sport am sure other hints could helpful neophyte know anything think might help someone little no experience slope let know will pass Slope types Another frequently asked question receive just shape slope af fects lift produced slope best way analyze lift site analyze cross sec tion slope specifically angle slope As general rule gentler slope say 300 will produce lighter lift over large area steeper slope approaching January 1989 161 Leo & MODEL BUILDING 7SERVICE RADIO CONTROL FROVUCTS carry full line Byron Originals Bob Parkerson Tom Cook Bob Violet products COD Orders Accepted 718 983-9735 128 WATCHOGUE ROAD EN SlAM 0314 Electric F ight Has Brake Lightweight 12 OLmosey hark Adjustable switching poiut guarantee easy hookup $249 ON/OFF Controller5 Power save weight aiZO Size 22x13x63 Very high efficiency 006' loss Add $105 shippiog Colitorojarosideots add 65% $163 Tss Send Check money order CoasesoithiiHIgh Sky Falaha sonsector Kansas St #9 otEaeeSan DiegoCA 92104 vertical will produce stronger lift over consider ably smaller area other words lift area slope directly related steepness slope wish fly stronger lift use up rel atively little available sky will want fly off cliff similar type slope would rather fly lighter consist ent lift will probably want fly slope quite steep Demon Tweaks have passed around modeling community some time Although theyre aimed specifically Slope Soar er hints trimming out Sailplane can immeasurable help give credit credit due believe Tweaks origi nated Pikes Peak Soaring Society newslet ter Spoiler specifically its edi tor Randy Reynolds Demon Tweak #1Make sure flying sur faces straight can done variety ways favorite simply sight down bottom surface wings stabs rear airplane suspicious surface can dis mounted double-checked flat surface such workbench flat right Trailing edges can sighted down similar manner check trueness particularly critical stab/elevator surfaces Demon Tweak #2It less fashionable days employ washout wing tips Washout trailing edge higher leading edge theory smaller chord tip would stall earlier root thus causing falloff tip another recommendation use washout since difference degree will cause erratic flightpath higher speeds such launch can check models tendency tip stall flight slowly bringing nose up until Glider stalls recovers straight ahead have washout bird good shape Demon Tweak #3Set up center-ofgravity properly Often kit plans call balanc ing spar frequently extremely conservative location will yield excellent sta bility very mediocre performance just learning fly leave ready handle performance should learn measure CG percentage wing chord able relate field experi ences percentage shop has two large blocks spruce tri angular pieces positioned halfway down block determine CG place assembled Glider triangular stock pieces un der wing root Balance Glider fore aft Measure distance triangular piece leading edge calculate per centage against full chord Generally speak ing trainers set up 30-33% Most higher-performance ships happiest 3538% Eppler 205 ships perform best 38% according pilots Use own judg ment wouldnt exceed 37% flatbottom airfoiled ships unless Top Gun caliber Demon Tweak #4Many entry-level ships observed climbing out launch shallow angles yield poor altitude Again kit manu facturers want safe suecessful therefore towhook positions extreme ward Once have learned fundamentals flying time tune towhook position CG Please think two factors insep arable generally place towhook exactly un der CG have always reliable high launches Most fliers position hook somewhat forward location perhaps / aggressive fliers looking maximum alti tude actually place hook behind CG What ever make changes several small steps starting hook ahead CG lo cation Authors note demon tweak obvi ously does apply Slope Soaring al though probably don' like admit some us occasionally some thermal flying Demon Tweak #5Most entry-level ships have narrow speed range would benefit installation turbulator strips devices tend reduce airflow separation top sur face improve performance during slow flight Studies have seen recommend two strips 10% chord measuring leading edge other 20-25% make turbulator strips Goldberg /32 color striping tape Typ ically strip laid directly top another yield bump thats repositionable decora tive tinkerers delight Bump Soaring What world Bump Soar ing Essentially Slope soaring slope thought needed large hill mountain range provide lift needed fly wrong needed create rising air enables Slope ships stay aloft something deflect change direction wind Thus need Bump Soar small ridge bump will deflect wind up wards some relatively strong winds have flown ridges small five six feet high have produced consistent lift winds 25-to-30 mph range lift does extend upwards very high strong enough maintain 25 50 ft altitude work ridge back forth What Bump Soaring does provide Slope flier opportunity polish skills learn mechanics Slope flying What type Sailplane need get volved Bump Soaring Unfortunately high-performance Racing ships just will able find lift needed unless happen flying hurricane-force winds type Sailplane best suited Bump Soaring light weight hand-launch type plane Most lighter thermal ships will able fly kind lift smaller plane better will able manage small lift area tight turns associated Bump Soaring would like try exciting diversion everyday Slope flying give Bump Soaring try very fun exhilarating way polish flying skills have opportunity travel favorite slope slope sites wanted Thanks High Performance Models presents ECL IPSE Designed Henry Piorun Former Canadian National Champion & FAI Canadian Team Member Designed Specifically FAI Pattern Flying Perform Equally Well Other AMA Classes Plug Wings rglass Belly Pan Pre-Cut Moles br Wing Joiner Tubes Ultralight Honeycomb Wingoores xfra404601 Optional Plastic Fiberglass Canopy Fiberglass Fuselage molded wing Joiner tube HIGH PERFORMANCE MODELS 9556116 st North Delta British Columbia 6Z4 Canada 604-588-0605 FINALLY Ultimate BOARD Designed & engineered WARP FREE construction HIGH-TECH MATERIAL Portable Ughtweight Conveniently Stored Large 20x78 Endgrain balsa block pin surface 314 deep Unaffected temperature humidity CASH PRICE $1 3500 Cai UPS VBA & MC 3700 BOULDER PORT ARTHUR TX 17640 409-982-8717 -F-who have sent details about favorite fly ing sites Although have received information number sites would really like have quite few put together really thorough complete directory slope sites send information favorite site please include such things prevailing winds slope gle landing area characteristics quality lift recommended flying experience directions and/or map local contact possible photo site Thanks again help project RC Scale/SruII Continued page 47 lected subtle shading keyword subtle Dont panels dont overdo Two colors will required high lights shadows Using basic air craft finish color add little white high light color little black shadow color Experiment first some scrap paper before tacking model Spray shadows first add highlights Remember Go easy dont overdo other method requires model sub structure supporting skin less scale model covered skinned somewhat flexible material does tally hide supporting substructure Major bulkheads stringers ribs spars model should located scale positions wherever pos sible Its usually good idea follow fullscale prototype structural layout anyhow scratch-building model rather totally re engineer perfectly good full-scale airplane de sign Rather using relatively stiff balsa skin typical balsa stock would firm %2 sheet plank model want use strong flexible covering material skin should flex distort small amount make internal structure visiblelike prototype Zero starved horse look usually work hard avoid just thing trying achieve case two materials have experience job nicely / ply /~ balsa / ply has very good tensile strength plus some flexibility best suited larger Scale models easiest use large pieces surfaces devoid compound curves such wing skins /16 firm balsa covering well-sanded %2 soft balsa well suited small-to-moderatesize models %- A-scale easy apply compound- high-curvature surfaces Being flexible will tend sag ripple /64 ply So depending scale model local skin strength required choose whichever best suits need case balsa skin will require layer lightweight glass cloth after attached framework will provide needed strength balsa well making surface hard enough finish standard practice edgegluing balsa sheets sanding smooth finish before attaching framework applies thin-skin structure used fi nal touch panel ripple should applied airbrush authentic look Now lets hear wrinkied-skin Zeros about target tow option least-seen interesting flight options suit able number Scale aircraft subjects target tow military training aircraft dating back Thirties pressed ser vice during WV II tow various flag sleeve targets use ground-to-air air-to-air gun nery practice An example Dreadnought version British Hawker Sea Fury fighter shown page 92 November 1988 issue MA nice plus target-tow airplanes sport interestlng distinctiveif garish color schemes ideal Scale model use sim ple reason bright color schemes flight crews wanted make absolutely sure tow aircraft could clearly seen dis tinguishable target sleeve nearsighted rookie gunnery student Though very interesting target tow simpler flight options Properly done INTRODUCING THE ELE7/JL/FE FOR 020-035-050 ELECTRICI\r SPAN 36 AREA 25T CHANNELS 2-3 ONOTH 3T FLYING WY 20 TO 30 OZ Designed built EIecSrlo Model Co 218 Oyster Ck r Land TX 77478 242-6229 Souths ingest inventory satro motors & accessories Need help wIth yow electdc ahplm orglder Ask Doe j~DuaIStrut Nose Gear Fults Tooling PO Box 95 Champaign IL 61820 NumberflistanReCe SF350 5 95 SF400 6 95 SF500 32 66901695 RF500 32 96-121595 RFY5T 321 SCSI1565 AAIosIabRGuadla OFROTlAs3116 1 seal 2995 PRODUCTS FOR THE DISCERNING MODELER Complete Line Exhaust Systems * Tuned led Tuned Pipes Headers uri Mufflers * Expansion Mufflers copter Ball Mufflers * Specialized Exhaust Systems Unsurpassed January 1989 163 Yes Virginia Santa Claus 2z Get Nearest Santas Shop 5sPeopIeof Com6ddem /mkc74 Aec Instantly removable sri-cycle gear wheels Pre-built boom landing gear sockets 8 push-roth Astro motor mount cobalt adapter Preformed leading edges knotched trailing edges Air frame 6 oz 75 ox landing gear Perfect performance 02003535 systems Maximum duration 8 glider-like motor-ofi flight characteristics ARF build 8 cover wing also completely built tail surfaces hinged . $7996 w/o gear $8695 gear ladd $3 eftipping TX res add 6% sales taxi
Edition: Model Aviation - 1989/01
Page Numbers: 42, 43, 159, 160, 161, 162, 163
QUESTIONS often appear letters arrive mail box following letter addressed Model Aviation forwarded pub lisher may concern ve flying RC planes about 4/2 years now started Goldberg Eagle 63 Over time able perform various stunts such loops barrel rolls inverted flight touch-and-go etc recently purchased built Goldberg Sky Tiger problem cant get plane turn rudder left right use rudder plane does flat turn cant get plane bank unless use ailerons banldng try level plane out rudder acts its sideslipping Say Im banking right give left rudder roll out bank Instead plane rolling left level flight plane stays bank nose goes up doing sideways flat turn tends cause loss altitude cant life figure problem out control throws set according instructions now need some experi enced advice correcting matter plane flies well except fact cant use rudder turn letter signed John Fleming Vernon NY wrote letter John rea lized problem might shared number fliers hadnt written letters Model Aviation seeking help information Its easy understand lack rolling response rudder control input would cause pilot accustomed beginner-type aircraft think problem perhaps ginner aircraft intentionally have too much dihe dral wing Consequently rudder deflected airplane starts sideslip dihedral wing generates rolling moment airplane banks direction rudder deflected So pilot thinks rudder caused bank Well suppose rudder did cause bank couldnt have happened wing dihedral So have two ways bank airplane rudder ailerons Thats good Right really Using rudder bank air plane fine long dont want turn airplane beginner airplanes dont have ailerons perform missions very well rather abrupt turns performed using rudder/wing dihedral banldng mechanism its hard tell Lift Airplane Weight Angle Attack atrim Figure 1 Ron discusses stability trim answers questions about Pattern models seemingly inexplicable things sometimes figure porlrays unique wing angle tack s needed sustain airplane level unaccelerated flight particular airspeed turns arent being done using ailerons However reason using rudder bank airplane satisfactory beginners dont tend fly airplanes inverted per form maneuvers like knife-edge flight point rolls want progress flying advanced ma neuvers must have airplane does bank rudder deflected roll airplane knife-edge apply top rud der keep nose up dont want wing dihedral cause airplane roll So benchmarks airplane Pattern flying potential absence rolling ten dency rudder deflected goal learn fly Pattern ma neuvers can bank airplane rudder reduce wing dihedral until doesnt What did tell John Fleming Sky Tiger doing just what its supposed Dont change anything Another letter arrived Wil liam Roper Englewood CO wrote long Pitching Moment Angle Attack atrim E3 Figure 2 series curves illustrtates pitching moments generated stable air plane constant airspeed several different elevator deflections E1 E2 E2 order trim plane unique elevator deflection generating zero pitching moment trim angle attack attm found Figure 1 necessary Only elevator deflectIon satisfies things 42 Model Aviation Radio Cono Sport Aerobatics Ron Van Putte Ill Sleepy Oaks Rd Ft Walton Beach FL 32548 happens pros AMA President Don Lowe examines spot cov ering missing wing Phoe nix 9 sure makes funny sound de parts during flight letter suppositions questions Wont quote whole letter just part along responses William started out like What Im trying sort out straight level unaccelerated flight Pattern airplane slowly rolled 900 either direction no other input applied airplane Im working now maintains altitude some dis tance heading changes toward direc tion roll ie pulls toward canopy RVP Obviously aircraft starts approach terra firma bank angle exceeds 450 noth ing oppose gravityno lift up about 450 bank aircraft starts almost circle since normal aircraft center-ofgravity must forward center-of-pressure some amount lest aircraft fall stall tail first circling tendency should ev ident Pattern aircraft some degree other Put another way Pattern aircraft trimmed straight unaccelerated flight will fly both upright inverted altitude change banking wings either upright inverted will produce heading change True way oppose heading change Pattern aircraft rolling maneuver judicious use rudder Which would also mean no such thing axial roll well-trimmed Pattern airplane barrel rolls altitude heading ex cursions too small detect True questions hit heart air planes really fly what differences tween trim stability Let clear air state impossible have airplane has trimmed straight level un accelerated flight rolled inverted have maintain altitude unless several complicated inter actions between engine wings fiAselage horizontal tail just right consider interaction just wings horizontal tail impossible no matter what Thats see few examples airplanes can trim just once both upright inverted flight mechanics level flight simple ten misunderstood shade tree aerody nainicists Im going bore Out skull lot equations just two simple curves will suffice get points across successful flying airplane Continued page 159 SAVE YOUR FIELD SNuF-LER muffler low cost easy install lightweight sound reducing muffler no performance penalty answer AMA muffler rule suggestions saving flying fields Meets AMA muffler rule suggestionsSNUF-LER 3 10 decIbels quieter stock mufflerMUFFLER No power loss possible 300-500 RPM increase Pat Pending Improves engine idle s better fuel economy Easily attached 25-108 stock mufflers Heat corrosion resistant Black E coat finish No special adapters required Weighs 35 oza Fits ASP BRAT ENYA FOX HP IRVINE K & B OS MAX ROYAL YS SUPER TIGRE mufflers available hobby shop ORDER DIRECT immediate shipment Check MO Visa MC CODSEND 25r STAMP accepted Add $250 UPS $205 tsr COD 6% sales taxFOR ADDITIONAL INFO Calif residentAND JTEC CATALOG January 1989 43 qqFP PUT YOURSELF AT ThE CONTROLS OF PROVEN GREAT FLYING WARDIRD almost ready fly kits have wing loadings lighter trainers very docile air land like Cub building-to-flying time very minimal fine kits together skill imagination will make plane crowd pleaser field Retracts now available Strong Light Reliable Pneumatics Idts come furnished fiberglass cowls WrIte call D&R Aircraft Mfg RO Box 23056 in TX 78736 512/288-2055 512/672-7023 Dealer Inquiries Invited $24 95 CAT NO 800 S Balsa0 Cutter5 T001~ 5 pc Masters Set 1/8 3/16 1/4 5/16 3/8 . $1698 3 pc Builders Set 3/161/4 5/16$998 Whether YOU kit builder scratch builder SQUARE CUT Tools will save time Remove stubborn die cuts cut own squares slots Made US quality machined zinc plated steel Order set today See Dealer Cataloger Order dont carry Square Cut Tools call us call well pay shipping SQUARE CUT Tools 4073 254-0516 905 N Harbor City Blvd Melbourne FL 32935 Florida Residents Dealer Distributor Inquiries Invitedadd 6% mien tax yr American Eaglet - was first light-plane receive type certificate Anorioan Eaglet carry two ooersdby LTMJ 05 motorpeople 45 horsepower ohkheosorv-Packooedintoisuros-The Eaglet complete itight system idOSA 1930s contemporary Aeronca C3 Taylor Cubs Health Parasol Pietenpol Air Camper Eaglets gentle flying characteristics reason flying schools day chose standard instructional aircraft Leisures easy-to-build scale model kit Amencan Eaglet 05 electric powered shares gentle Keiths flight itsomething hed wanted 1985 couldnt because Teds preemptive action Anyway seeing oles own design being flown Master happy humbling experience very much enjoyed particular flight Keith routinely flies oth ers models asked OK Mitch Maybe will publish Would like kit Ted sad thing about KRC meet ends good thing have en joyed continuance others hard imagine next year will mark 10th anniversary KRC Electric Fly What began dubious risky one-day affair 1980 tracted three icipants has matured two annual days sheer joy excitement happiness two days re charging friendships associations made past two days new memories ac quaintances formed year two days Electric advancement achievement shared displayed allwith having come mean over 100 participants hundreds spec tators Its heckofa flight folks have comments youd like share other Electrickers Please send themor questions SASE please ad dress given box very beginning column sincere thanks numerous folks came Fly comment favorably column appreciate interest feel ing taking time say flight characteristics full scale aircraft Scaled 18 inches-to-foot model features span 62 inches wing area 571 square inches Its lightweight structure 4041 oz flying weight allows low wing loading 104 ounces per square foot combined Leisure flight system turning 11 x 5 prop flight performance spectacular Takeoff occurs after 20 foot ground roll climb-out brisk model has thermaled moderate lift conditions Gentle landings breeze Scale details documentation included plans make scale contest winner Rsr afree copy Leisures new full color catalog send stamped self addressed business sized envelope Leisure Electrenics Inc 22971 Triton Way Unit B Lesguna Hills C4 92653 RC AerobaticsNan Putte Continued page 43 must able trimned must sta ble airplane trimmed steady level flight forces moments acting must add up zero means lift equals weight thrust equal drag no net pitching moment present two curves referred lift pitching moment curves Figure 1 shows rela tionship between lift generated given speed aircraft angle attack can see theres angle attack lift equals airplane weight airplane must angle attack maintain unaccelerated level flight airspeed chosen exam ple called trim angle attack Theres different trim angle attack another airspeed airplane angle attack higher trim angle attack will tend climb vice versa second Figure 2 curve really set curves shows pitching moment generated stable airplane given speed function airplane angle attack several elevator set tings pitching moment muat zero trim curve can pass through zero pitching moment aircrafts trim angle tack lift equals airplane weight curve labeled E2 corresponds particular elevator position summarize given airspeed angle attack elevator setting airplane will maintain unaccelerated level flight change throttle setting consume fuel trim attitude airplane will change elevator deflection required Leisure achieve will change well have prob ably noted airplanes trim changes fuel consumed flight speed changed Airplanes can designed minimize ef fects will always present degree Now what about William Ropers problem take airplane steady level flight roll 90 roll performed almost about axis line direction airplane flying call rolling about velocity vector airplane rolled 900 about axis lift wing does change However now lift countering airplanes weight fact its pointed perpen dicular Newtons laws obviously work situation airplane accelerates direction perpendicular wings downward well So much mystery What happens airplane rolled less 45 ally same forces present airplane rolled 90 effect reduced Consequently air plane will start gentle turn due unopposed part lift generated wing airplanes descent reduced because substan tial fraction lift available counter airplanes weight Consequently airplane will enter descending torn So does banking produce heading change Yes suggestion made William Roper way oppose heading change rolling maneuver judicious use rudder What suggested true However dont know anyone fast enough right amount rudder counter heading changes good news takes time airplanes heading change very much since supposed perform three rolls five seconds heading changes dont have January 1989 159 New Leisure introduces electric scale American Eaglet responding advertisers mention thatyou read about ModelAviation lot time develop allegation nobody does axial roll true lift force being developed wings rotates around airplane rolls air plane accelerates direction unop posed force means path air plane cannot straight Obviously some air planes better others performing axial rolls barrel roll degree RC Slope Soaring/Triebes Continued page 45 ships Can imagine what would say someone claimed powered plane fully acrobatic asymmetrical wing no rud der same goes Slope Soarers snap rolls four-point rolls clean hammerheads other maneuvers must have rudder side outside maneuvers have same size shape symmetrical alrfoil pretty much necessity almost no Slope kits fully acrobatic writers like yourself keep sisting todays crop planes like Savage its progeny SR-7 forth good are fully aerobatic think will see new breed Another thing will further good designs contests CD thinks nothing call ing outside loops inverted flight rolling circles one-and-a-half snaps vertical eights Jef makes some very good points am sure Slope Soaring continues grow MINI-JET SERIES planes feature balsa construction Designed intermediate flyer in A4 mind will accept 20-25 size engine fuse rear exhaust engine exceptional Skyhawk performancel thrill jet heesles ducted fan $4000 &H Proud Bird deeignad meet OSPRA Formula 120 rules 114 scale model will accept 60-120 ci size engines Epoxy glees fueelage foam wing construction Full kit $150 Semi-kit also available Inn woodi $i25 Please add $10 S&H F-20 Tlgenhark Send check money order COD add $300 esidents add 6% sales tsx Dart ExperImental two-place full size alrr5ft Top Turkey Formula 1 $85$5S&H PARRISH AIRCRAFTScale Models ll25SW49thTer Plantation FL33317 will see new designs emerging number hoped will fully acrobatic Jef also looking some information help him evaluate relative merits different sym metrical airfoils Slope Soaring Aerobatics Any information can get subject would greatly appreciated Jefs name sounds familiar some probably because principal people involved developing Apple Macin tosh computer Jef also wrote program Micro soft Basic Mac will calculate coordi nates display picture NACA fourdigit airfoil appears Martin Hollmanns book Modem Aircraft Design very inter esting us designer types play would like listing program send SASE two stamps please Spitfire Slope LeRoy Satterlee Wa terloo IA sent couple photos beautiful Spitfire Mk XII built John Lupperger Plans Service plans what has say about designed 25-size power plane orig inally did build light leave off engine finished plane flown aile ron elevator no rudder wing loading 925 oz per sq ft made slow est flying Spitfire anyone could remember having seen addition about 10 oz lead picked up flying speed plane flew much solidly experiments will continue re turn hill later year ever build another Spitfire Ill build heavier use thin ner airfoil some kind get speed up further Power Slope Scale fun di version recommend everyone LeRoy flying buddies travel two-and-ahalf hours southeastern Wisconsin Slope flying sald Slope fliers dedi cated Four group including LeRoy have completed LSF Level 5 eight-hour slope flights Superslope Tom Rent member fleer Minnesota RC Soaring Society gives further evidence Slope Soaring alive well Midwest club relatively large approaching 100 members have recently discovered 160 Model Aviation CA MASK CA glue works wonders building models right Unfortunately gives enough fumes knock vulture off carcass modelers have suffered medical problems after inhaling CA fumes take chances special vapor respirator filters CA fumesl soft face mask adjustable straps comfortably fits face sizes easy breathing valve allows prolonged use providing dependable filtering concentrations up 1000 PPM though rugged industrial mask light weight elimi nate fatigue Dont get gassed CA Get protected Order CA Mask today Just $1247 shipping cheaper hospital visit Money order Master Charge Visa include expiration date check allow 20 days clear Sorry no CODs Pelican Enterprises 2540 RIDGE ROAD LANSING ILLINOIS 60438 P S Send catalog modelers safety supplies 305 581-4477 Latest Japanese Pattern Design Designed & Flown TOP Japanese Pilot Suitable FAI AMA Classes tCa5a FberRedewd EtrexyiSasa FuaabgaSpa, -57 wing Area 750 eq 2 Fe 5e Siesied Cake FbarRakfrexedUkeLld HxeepaenA PraitWhrs 3Fadxy5traahd a5patle& raesrieeke 41W errewarhised hedre ed 5 Pawt FeaeI Now Offered Super Deluxe Pm-Built Kit $45000 Completely Finished Model Call info & pricing VISA& MASTERCARD WELCOME Pteae add $t5mt Srr& Hadna inidaadd &5%.15550dntwa&AdaCewayNPhone408298-0311 FAX#408298-6538 IA NEW ELECTRIC Fly .. great stand-way-off scale fun ship designed 05 electric power can perform take-offs touch goes aerobatics beauty yet enjoy docile slow flight easy landings Quick easy build kit includes pre cut fuselage sides tail feathers small parts hardware complete rolled plans step-by-step instructions formed landing gear windshield Electro-Combo includes kit DSC 075 Hyperthrust motor fused switch harness Tamiya connector propeller adaptor 8/4 fiberglass propeller 40 Span 275 Sq area 32 oz flying weight flat bottom airfoil rudder elevator motor add ailerons too SPECIAL COMBO PRICE $4795 IPAVEY675 YSTEMSWEST CHESTEF PA 193& BASIC KIT $244oRRATloN215~ wonderful world Slope Soaring Although true Midwest flat some areas blessed beautiftil grass-covered hills provided retreating glaciers site Superslope call Nerstrand MN perfect come Picture Steep grass-covered face road parking area top wide face no trees unobstructed flatlands below smooth airflow remote location no houses traffic its 30-to-40-minute drive Twin Cities Rochester am continually surprised number Slope fliers located Midwest Slope Soaring has long considered coastal sport caters mainly California crowd rapidly gaining reputation universal branch Soaring Beginner hints letters receive fliers new Slope Soaring ask ing few hints finding good site mak ing first flight help position also remind us little experienced basics Slope fly ing Finding good site really too difficult principle reality may turn out some what harder depending location ex perience ideal slope site would range foothills unobstructed face no trees bushes etc looks prevailing winds Actual size hill really important have flown off 5000-ft peaks off 10ft ridges What important find site faces steady relatively strong 10-30 mph winds will want find hill ridge has clear unobstructed top land ing easiest general really need take Sailplane will fly light conditions day conditions such go out vestigate possible sites cannot really de termine anything about quality site until have flown off Some best sites look nearly good vice versa As flying itself let offer couple comments should get through begin ning stages First predominant lift slope generated area about 450 top hill angle going wind commonly used technique fly back forth across face hill remaining 450 column air really difficult might sound simply location best lift reality lift just about everywhere windward side hill important thing remember get behind hill rotors develop downwind side hill have destroyed Sailplanes characteristic Slope Soaring probably difficult begin ners overcome simplest way keep out trouble imagine wall extends along top hill ridge must remain front wall stay clean air avoid downdrafts other side Once have few hours experience Slope flying will able investigate area tually youll able use advantage landing beginner place stay clear As launching will want take few steps down face hill avoid having plane thrown back behind hill Simply give plane good toss straight wind continue fly straight out until stronger lift Landing quite simple launching still difficult As beginner will probably want land going across face hill simplest surest way getting down getting caught behind hill stalling plane trying slow down too much Just fly plane slowly possible across face slightly below top hill continue lower lower until can land certainly neither pretti est nor purist way land its effective somewhat easier beginner Once have little experience will able use rotors behind hill re duced lift top hill simply lower plane down land top would rec ommend method until have logged few hours comfortable flying slope After said done best way learn fly slope simply probably saying yourself easy say being experienced Sloper just beginner beginners time us learned fly slope just doing methods beginning Sloping have helped people get sport am sure other hints could helpful neophyte know anything think might help someone little no experience slope let know will pass Slope types Another frequently asked question receive just shape slope af fects lift produced slope best way analyze lift site analyze cross sec tion slope specifically angle slope As general rule gentler slope say 300 will produce lighter lift over large area steeper slope approaching January 1989 161 Leo & MODEL BUILDING 7SERVICE RADIO CONTROL FROVUCTS carry full line Byron Originals Bob Parkerson Tom Cook Bob Violet products COD Orders Accepted 718 983-9735 128 WATCHOGUE ROAD EN SlAM 0314 Electric F ight Has Brake Lightweight 12 OLmosey hark Adjustable switching poiut guarantee easy hookup $249 ON/OFF Controller5 Power save weight aiZO Size 22x13x63 Very high efficiency 006' loss Add $105 shippiog Colitorojarosideots add 65% $163 Tss Send Check money order CoasesoithiiHIgh Sky Falaha sonsector Kansas St #9 otEaeeSan DiegoCA 92104 vertical will produce stronger lift over consider ably smaller area other words lift area slope directly related steepness slope wish fly stronger lift use up rel atively little available sky will want fly off cliff similar type slope would rather fly lighter consist ent lift will probably want fly slope quite steep Demon Tweaks have passed around modeling community some time Although theyre aimed specifically Slope Soar er hints trimming out Sailplane can immeasurable help give credit credit due believe Tweaks origi nated Pikes Peak Soaring Society newslet ter Spoiler specifically its edi tor Randy Reynolds Demon Tweak #1Make sure flying sur faces straight can done variety ways favorite simply sight down bottom surface wings stabs rear airplane suspicious surface can dis mounted double-checked flat surface such workbench flat right Trailing edges can sighted down similar manner check trueness particularly critical stab/elevator surfaces Demon Tweak #2It less fashionable days employ washout wing tips Washout trailing edge higher leading edge theory smaller chord tip would stall earlier root thus causing falloff tip another recommendation use washout since difference degree will cause erratic flightpath higher speeds such launch can check models tendency tip stall flight slowly bringing nose up until Glider stalls recovers straight ahead have washout bird good shape Demon Tweak #3Set up center-ofgravity properly Often kit plans call balanc ing spar frequently extremely conservative location will yield excellent sta bility very mediocre performance just learning fly leave ready handle performance should learn measure CG percentage wing chord able relate field experi ences percentage shop has two large blocks spruce tri angular pieces positioned halfway down block determine CG place assembled Glider triangular stock pieces un der wing root Balance Glider fore aft Measure distance triangular piece leading edge calculate per centage against full chord Generally speak ing trainers set up 30-33% Most higher-performance ships happiest 3538% Eppler 205 ships perform best 38% according pilots Use own judg ment wouldnt exceed 37% flatbottom airfoiled ships unless Top Gun caliber Demon Tweak #4Many entry-level ships observed climbing out launch shallow angles yield poor altitude Again kit manu facturers want safe suecessful therefore towhook positions extreme ward Once have learned fundamentals flying time tune towhook position CG Please think two factors insep arable generally place towhook exactly un der CG have always reliable high launches Most fliers position hook somewhat forward location perhaps / aggressive fliers looking maximum alti tude actually place hook behind CG What ever make changes several small steps starting hook ahead CG lo cation Authors note demon tweak obvi ously does apply Slope Soaring al though probably don' like admit some us occasionally some thermal flying Demon Tweak #5Most entry-level ships have narrow speed range would benefit installation turbulator strips devices tend reduce airflow separation top sur face improve performance during slow flight Studies have seen recommend two strips 10% chord measuring leading edge other 20-25% make turbulator strips Goldberg /32 color striping tape Typ ically strip laid directly top another yield bump thats repositionable decora tive tinkerers delight Bump Soaring What world Bump Soar ing Essentially Slope soaring slope thought needed large hill mountain range provide lift needed fly wrong needed create rising air enables Slope ships stay aloft something deflect change direction wind Thus need Bump Soar small ridge bump will deflect wind up wards some relatively strong winds have flown ridges small five six feet high have produced consistent lift winds 25-to-30 mph range lift does extend upwards very high strong enough maintain 25 50 ft altitude work ridge back forth What Bump Soaring does provide Slope flier opportunity polish skills learn mechanics Slope flying What type Sailplane need get volved Bump Soaring Unfortunately high-performance Racing ships just will able find lift needed unless happen flying hurricane-force winds type Sailplane best suited Bump Soaring light weight hand-launch type plane Most lighter thermal ships will able fly kind lift smaller plane better will able manage small lift area tight turns associated Bump Soaring would like try exciting diversion everyday Slope flying give Bump Soaring try very fun exhilarating way polish flying skills have opportunity travel favorite slope slope sites wanted Thanks High Performance Models presents ECL IPSE Designed Henry Piorun Former Canadian National Champion & FAI Canadian Team Member Designed Specifically FAI Pattern Flying Perform Equally Well Other AMA Classes Plug Wings rglass Belly Pan Pre-Cut Moles br Wing Joiner Tubes Ultralight Honeycomb Wingoores xfra404601 Optional Plastic Fiberglass Canopy Fiberglass Fuselage molded wing Joiner tube HIGH PERFORMANCE MODELS 9556116 st North Delta British Columbia 6Z4 Canada 604-588-0605 FINALLY Ultimate BOARD Designed & engineered WARP FREE construction HIGH-TECH MATERIAL Portable Ughtweight Conveniently Stored Large 20x78 Endgrain balsa block pin surface 314 deep Unaffected temperature humidity CASH PRICE $1 3500 Cai UPS VBA & MC 3700 BOULDER PORT ARTHUR TX 17640 409-982-8717 -F-who have sent details about favorite fly ing sites Although have received information number sites would really like have quite few put together really thorough complete directory slope sites send information favorite site please include such things prevailing winds slope gle landing area characteristics quality lift recommended flying experience directions and/or map local contact possible photo site Thanks again help project RC Scale/SruII Continued page 47 lected subtle shading keyword subtle Dont panels dont overdo Two colors will required high lights shadows Using basic air craft finish color add little white high light color little black shadow color Experiment first some scrap paper before tacking model Spray shadows first add highlights Remember Go easy dont overdo other method requires model sub structure supporting skin less scale model covered skinned somewhat flexible material does tally hide supporting substructure Major bulkheads stringers ribs spars model should located scale positions wherever pos sible Its usually good idea follow fullscale prototype structural layout anyhow scratch-building model rather totally re engineer perfectly good full-scale airplane de sign Rather using relatively stiff balsa skin typical balsa stock would firm %2 sheet plank model want use strong flexible covering material skin should flex distort small amount make internal structure visiblelike prototype Zero starved horse look usually work hard avoid just thing trying achieve case two materials have experience job nicely / ply /~ balsa / ply has very good tensile strength plus some flexibility best suited larger Scale models easiest use large pieces surfaces devoid compound curves such wing skins /16 firm balsa covering well-sanded %2 soft balsa well suited small-to-moderatesize models %- A-scale easy apply compound- high-curvature surfaces Being flexible will tend sag ripple /64 ply So depending scale model local skin strength required choose whichever best suits need case balsa skin will require layer lightweight glass cloth after attached framework will provide needed strength balsa well making surface hard enough finish standard practice edgegluing balsa sheets sanding smooth finish before attaching framework applies thin-skin structure used fi nal touch panel ripple should applied airbrush authentic look Now lets hear wrinkied-skin Zeros about target tow option least-seen interesting flight options suit able number Scale aircraft subjects target tow military training aircraft dating back Thirties pressed ser vice during WV II tow various flag sleeve targets use ground-to-air air-to-air gun nery practice An example Dreadnought version British Hawker Sea Fury fighter shown page 92 November 1988 issue MA nice plus target-tow airplanes sport interestlng distinctiveif garish color schemes ideal Scale model use sim ple reason bright color schemes flight crews wanted make absolutely sure tow aircraft could clearly seen dis tinguishable target sleeve nearsighted rookie gunnery student Though very interesting target tow simpler flight options Properly done INTRODUCING THE ELE7/JL/FE FOR 020-035-050 ELECTRICI\r SPAN 36 AREA 25T CHANNELS 2-3 ONOTH 3T FLYING WY 20 TO 30 OZ Designed built EIecSrlo Model Co 218 Oyster Ck r Land TX 77478 242-6229 Souths ingest inventory satro motors & accessories Need help wIth yow electdc ahplm orglder Ask Doe j~DuaIStrut Nose Gear Fults Tooling PO Box 95 Champaign IL 61820 NumberflistanReCe SF350 5 95 SF400 6 95 SF500 32 66901695 RF500 32 96-121595 RFY5T 321 SCSI1565 AAIosIabRGuadla OFROTlAs3116 1 seal 2995 PRODUCTS FOR THE DISCERNING MODELER Complete Line Exhaust Systems * Tuned led Tuned Pipes Headers uri Mufflers * Expansion Mufflers copter Ball Mufflers * Specialized Exhaust Systems Unsurpassed January 1989 163 Yes Virginia Santa Claus 2z Get Nearest Santas Shop 5sPeopIeof Com6ddem /mkc74 Aec Instantly removable sri-cycle gear wheels Pre-built boom landing gear sockets 8 push-roth Astro motor mount cobalt adapter Preformed leading edges knotched trailing edges Air frame 6 oz 75 ox landing gear Perfect performance 02003535 systems Maximum duration 8 glider-like motor-ofi flight characteristics ARF build 8 cover wing also completely built tail surfaces hinged . $7996 w/o gear $8695 gear ladd $3 eftipping TX res add 6% sales taxi
Edition: Model Aviation - 1989/01
Page Numbers: 42, 43, 159, 160, 161, 162, 163
QUESTIONS often appear letters arrive mail box following letter addressed Model Aviation forwarded pub lisher may concern ve flying RC planes about 4/2 years now started Goldberg Eagle 63 Over time able perform various stunts such loops barrel rolls inverted flight touch-and-go etc recently purchased built Goldberg Sky Tiger problem cant get plane turn rudder left right use rudder plane does flat turn cant get plane bank unless use ailerons banldng try level plane out rudder acts its sideslipping Say Im banking right give left rudder roll out bank Instead plane rolling left level flight plane stays bank nose goes up doing sideways flat turn tends cause loss altitude cant life figure problem out control throws set according instructions now need some experi enced advice correcting matter plane flies well except fact cant use rudder turn letter signed John Fleming Vernon NY wrote letter John rea lized problem might shared number fliers hadnt written letters Model Aviation seeking help information Its easy understand lack rolling response rudder control input would cause pilot accustomed beginner-type aircraft think problem perhaps ginner aircraft intentionally have too much dihe dral wing Consequently rudder deflected airplane starts sideslip dihedral wing generates rolling moment airplane banks direction rudder deflected So pilot thinks rudder caused bank Well suppose rudder did cause bank couldnt have happened wing dihedral So have two ways bank airplane rudder ailerons Thats good Right really Using rudder bank air plane fine long dont want turn airplane beginner airplanes dont have ailerons perform missions very well rather abrupt turns performed using rudder/wing dihedral banldng mechanism its hard tell Lift Airplane Weight Angle Attack atrim Figure 1 Ron discusses stability trim answers questions about Pattern models seemingly inexplicable things sometimes figure porlrays unique wing angle tack s needed sustain airplane level unaccelerated flight particular airspeed turns arent being done using ailerons However reason using rudder bank airplane satisfactory beginners dont tend fly airplanes inverted per form maneuvers like knife-edge flight point rolls want progress flying advanced ma neuvers must have airplane does bank rudder deflected roll airplane knife-edge apply top rud der keep nose up dont want wing dihedral cause airplane roll So benchmarks airplane Pattern flying potential absence rolling ten dency rudder deflected goal learn fly Pattern ma neuvers can bank airplane rudder reduce wing dihedral until doesnt What did tell John Fleming Sky Tiger doing just what its supposed Dont change anything Another letter arrived Wil liam Roper Englewood CO wrote long Pitching Moment Angle Attack atrim E3 Figure 2 series curves illustrtates pitching moments generated stable air plane constant airspeed several different elevator deflections E1 E2 E2 order trim plane unique elevator deflection generating zero pitching moment trim angle attack attm found Figure 1 necessary Only elevator deflectIon satisfies things 42 Model Aviation Radio Cono Sport Aerobatics Ron Van Putte Ill Sleepy Oaks Rd Ft Walton Beach FL 32548 happens pros AMA President Don Lowe examines spot cov ering missing wing Phoe nix 9 sure makes funny sound de parts during flight letter suppositions questions Wont quote whole letter just part along responses William started out like What Im trying sort out straight level unaccelerated flight Pattern airplane slowly rolled 900 either direction no other input applied airplane Im working now maintains altitude some dis tance heading changes toward direc tion roll ie pulls toward canopy RVP Obviously aircraft starts approach terra firma bank angle exceeds 450 noth ing oppose gravityno lift up about 450 bank aircraft starts almost circle since normal aircraft center-ofgravity must forward center-of-pressure some amount lest aircraft fall stall tail first circling tendency should ev ident Pattern aircraft some degree other Put another way Pattern aircraft trimmed straight unaccelerated flight will fly both upright inverted altitude change banking wings either upright inverted will produce heading change True way oppose heading change Pattern aircraft rolling maneuver judicious use rudder Which would also mean no such thing axial roll well-trimmed Pattern airplane barrel rolls altitude heading ex cursions too small detect True questions hit heart air planes really fly what differences tween trim stability Let clear air state impossible have airplane has trimmed straight level un accelerated flight rolled inverted have maintain altitude unless several complicated inter actions between engine wings fiAselage horizontal tail just right consider interaction just wings horizontal tail impossible no matter what Thats see few examples airplanes can trim just once both upright inverted flight mechanics level flight simple ten misunderstood shade tree aerody nainicists Im going bore Out skull lot equations just two simple curves will suffice get points across successful flying airplane Continued page 159 SAVE YOUR FIELD SNuF-LER muffler low cost easy install lightweight sound reducing muffler no performance penalty answer AMA muffler rule suggestions saving flying fields Meets AMA muffler rule suggestionsSNUF-LER 3 10 decIbels quieter stock mufflerMUFFLER No power loss possible 300-500 RPM increase Pat Pending Improves engine idle s better fuel economy Easily attached 25-108 stock mufflers Heat corrosion resistant Black E coat finish No special adapters required Weighs 35 oza Fits ASP BRAT ENYA FOX HP IRVINE K & B OS MAX ROYAL YS SUPER TIGRE mufflers available hobby shop ORDER DIRECT immediate shipment Check MO Visa MC CODSEND 25r STAMP accepted Add $250 UPS $205 tsr COD 6% sales taxFOR ADDITIONAL INFO Calif residentAND JTEC CATALOG January 1989 43 qqFP PUT YOURSELF AT ThE CONTROLS OF PROVEN GREAT FLYING WARDIRD almost ready fly kits have wing loadings lighter trainers very docile air land like Cub building-to-flying time very minimal fine kits together skill imagination will make plane crowd pleaser field Retracts now available Strong Light Reliable Pneumatics Idts come furnished fiberglass cowls WrIte call D&R Aircraft Mfg RO Box 23056 in TX 78736 512/288-2055 512/672-7023 Dealer Inquiries Invited $24 95 CAT NO 800 S Balsa0 Cutter5 T001~ 5 pc Masters Set 1/8 3/16 1/4 5/16 3/8 . $1698 3 pc Builders Set 3/161/4 5/16$998 Whether YOU kit builder scratch builder SQUARE CUT Tools will save time Remove stubborn die cuts cut own squares slots Made US quality machined zinc plated steel Order set today See Dealer Cataloger Order dont carry Square Cut Tools call us call well pay shipping SQUARE CUT Tools 4073 254-0516 905 N Harbor City Blvd Melbourne FL 32935 Florida Residents Dealer Distributor Inquiries Invitedadd 6% mien tax yr American Eaglet - was first light-plane receive type certificate Anorioan Eaglet carry two ooersdby LTMJ 05 motorpeople 45 horsepower ohkheosorv-Packooedintoisuros-The Eaglet complete itight system idOSA 1930s contemporary Aeronca C3 Taylor Cubs Health Parasol Pietenpol Air Camper Eaglets gentle flying characteristics reason flying schools day chose standard instructional aircraft Leisures easy-to-build scale model kit Amencan Eaglet 05 electric powered shares gentle Keiths flight itsomething hed wanted 1985 couldnt because Teds preemptive action Anyway seeing oles own design being flown Master happy humbling experience very much enjoyed particular flight Keith routinely flies oth ers models asked OK Mitch Maybe will publish Would like kit Ted sad thing about KRC meet ends good thing have en joyed continuance others hard imagine next year will mark 10th anniversary KRC Electric Fly What began dubious risky one-day affair 1980 tracted three icipants has matured two annual days sheer joy excitement happiness two days re charging friendships associations made past two days new memories ac quaintances formed year two days Electric advancement achievement shared displayed allwith having come mean over 100 participants hundreds spec tators Its heckofa flight folks have comments youd like share other Electrickers Please send themor questions SASE please ad dress given box very beginning column sincere thanks numerous folks came Fly comment favorably column appreciate interest feel ing taking time say flight characteristics full scale aircraft Scaled 18 inches-to-foot model features span 62 inches wing area 571 square inches Its lightweight structure 4041 oz flying weight allows low wing loading 104 ounces per square foot combined Leisure flight system turning 11 x 5 prop flight performance spectacular Takeoff occurs after 20 foot ground roll climb-out brisk model has thermaled moderate lift conditions Gentle landings breeze Scale details documentation included plans make scale contest winner Rsr afree copy Leisures new full color catalog send stamped self addressed business sized envelope Leisure Electrenics Inc 22971 Triton Way Unit B Lesguna Hills C4 92653 RC AerobaticsNan Putte Continued page 43 must able trimned must sta ble airplane trimmed steady level flight forces moments acting must add up zero means lift equals weight thrust equal drag no net pitching moment present two curves referred lift pitching moment curves Figure 1 shows rela tionship between lift generated given speed aircraft angle attack can see theres angle attack lift equals airplane weight airplane must angle attack maintain unaccelerated level flight airspeed chosen exam ple called trim angle attack Theres different trim angle attack another airspeed airplane angle attack higher trim angle attack will tend climb vice versa second Figure 2 curve really set curves shows pitching moment generated stable airplane given speed function airplane angle attack several elevator set tings pitching moment muat zero trim curve can pass through zero pitching moment aircrafts trim angle tack lift equals airplane weight curve labeled E2 corresponds particular elevator position summarize given airspeed angle attack elevator setting airplane will maintain unaccelerated level flight change throttle setting consume fuel trim attitude airplane will change elevator deflection required Leisure achieve will change well have prob ably noted airplanes trim changes fuel consumed flight speed changed Airplanes can designed minimize ef fects will always present degree Now what about William Ropers problem take airplane steady level flight roll 90 roll performed almost about axis line direction airplane flying call rolling about velocity vector airplane rolled 900 about axis lift wing does change However now lift countering airplanes weight fact its pointed perpen dicular Newtons laws obviously work situation airplane accelerates direction perpendicular wings downward well So much mystery What happens airplane rolled less 45 ally same forces present airplane rolled 90 effect reduced Consequently air plane will start gentle turn due unopposed part lift generated wing airplanes descent reduced because substan tial fraction lift available counter airplanes weight Consequently airplane will enter descending torn So does banking produce heading change Yes suggestion made William Roper way oppose heading change rolling maneuver judicious use rudder What suggested true However dont know anyone fast enough right amount rudder counter heading changes good news takes time airplanes heading change very much since supposed perform three rolls five seconds heading changes dont have January 1989 159 New Leisure introduces electric scale American Eaglet responding advertisers mention thatyou read about ModelAviation lot time develop allegation nobody does axial roll true lift force being developed wings rotates around airplane rolls air plane accelerates direction unop posed force means path air plane cannot straight Obviously some air planes better others performing axial rolls barrel roll degree RC Slope Soaring/Triebes Continued page 45 ships Can imagine what would say someone claimed powered plane fully acrobatic asymmetrical wing no rud der same goes Slope Soarers snap rolls four-point rolls clean hammerheads other maneuvers must have rudder side outside maneuvers have same size shape symmetrical alrfoil pretty much necessity almost no Slope kits fully acrobatic writers like yourself keep sisting todays crop planes like Savage its progeny SR-7 forth good are fully aerobatic think will see new breed Another thing will further good designs contests CD thinks nothing call ing outside loops inverted flight rolling circles one-and-a-half snaps vertical eights Jef makes some very good points am sure Slope Soaring continues grow MINI-JET SERIES planes feature balsa construction Designed intermediate flyer in A4 mind will accept 20-25 size engine fuse rear exhaust engine exceptional Skyhawk performancel thrill jet heesles ducted fan $4000 &H Proud Bird deeignad meet OSPRA Formula 120 rules 114 scale model will accept 60-120 ci size engines Epoxy glees fueelage foam wing construction Full kit $150 Semi-kit also available Inn woodi $i25 Please add $10 S&H F-20 Tlgenhark Send check money order COD add $300 esidents add 6% sales tsx Dart ExperImental two-place full size alrr5ft Top Turkey Formula 1 $85$5S&H PARRISH AIRCRAFTScale Models ll25SW49thTer Plantation FL33317 will see new designs emerging number hoped will fully acrobatic Jef also looking some information help him evaluate relative merits different sym metrical airfoils Slope Soaring Aerobatics Any information can get subject would greatly appreciated Jefs name sounds familiar some probably because principal people involved developing Apple Macin tosh computer Jef also wrote program Micro soft Basic Mac will calculate coordi nates display picture NACA fourdigit airfoil appears Martin Hollmanns book Modem Aircraft Design very inter esting us designer types play would like listing program send SASE two stamps please Spitfire Slope LeRoy Satterlee Wa terloo IA sent couple photos beautiful Spitfire Mk XII built John Lupperger Plans Service plans what has say about designed 25-size power plane orig inally did build light leave off engine finished plane flown aile ron elevator no rudder wing loading 925 oz per sq ft made slow est flying Spitfire anyone could remember having seen addition about 10 oz lead picked up flying speed plane flew much solidly experiments will continue re turn hill later year ever build another Spitfire Ill build heavier use thin ner airfoil some kind get speed up further Power Slope Scale fun di version recommend everyone LeRoy flying buddies travel two-and-ahalf hours southeastern Wisconsin Slope flying sald Slope fliers dedi cated Four group including LeRoy have completed LSF Level 5 eight-hour slope flights Superslope Tom Rent member fleer Minnesota RC Soaring Society gives further evidence Slope Soaring alive well Midwest club relatively large approaching 100 members have recently discovered 160 Model Aviation CA MASK CA glue works wonders building models right Unfortunately gives enough fumes knock vulture off carcass modelers have suffered medical problems after inhaling CA fumes take chances special vapor respirator filters CA fumesl soft face mask adjustable straps comfortably fits face sizes easy breathing valve allows prolonged use providing dependable filtering concentrations up 1000 PPM though rugged industrial mask light weight elimi nate fatigue Dont get gassed CA Get protected Order CA Mask today Just $1247 shipping cheaper hospital visit Money order Master Charge Visa include expiration date check allow 20 days clear Sorry no CODs Pelican Enterprises 2540 RIDGE ROAD LANSING ILLINOIS 60438 P S Send catalog modelers safety supplies 305 581-4477 Latest Japanese Pattern Design Designed & Flown TOP Japanese Pilot Suitable FAI AMA Classes tCa5a FberRedewd EtrexyiSasa FuaabgaSpa, -57 wing Area 750 eq 2 Fe 5e Siesied Cake FbarRakfrexedUkeLld HxeepaenA PraitWhrs 3Fadxy5traahd a5patle& raesrieeke 41W errewarhised hedre ed 5 Pawt FeaeI Now Offered Super Deluxe Pm-Built Kit $45000 Completely Finished Model Call info & pricing VISA& MASTERCARD WELCOME Pteae add $t5mt Srr& Hadna inidaadd &5%.15550dntwa&AdaCewayNPhone408298-0311 FAX#408298-6538 IA NEW ELECTRIC Fly .. great stand-way-off scale fun ship designed 05 electric power can perform take-offs touch goes aerobatics beauty yet enjoy docile slow flight easy landings Quick easy build kit includes pre cut fuselage sides tail feathers small parts hardware complete rolled plans step-by-step instructions formed landing gear windshield Electro-Combo includes kit DSC 075 Hyperthrust motor fused switch harness Tamiya connector propeller adaptor 8/4 fiberglass propeller 40 Span 275 Sq area 32 oz flying weight flat bottom airfoil rudder elevator motor add ailerons too SPECIAL COMBO PRICE $4795 IPAVEY675 YSTEMSWEST CHESTEF PA 193& BASIC KIT $244oRRATloN215~ wonderful world Slope Soaring Although true Midwest flat some areas blessed beautiftil grass-covered hills provided retreating glaciers site Superslope call Nerstrand MN perfect come Picture Steep grass-covered face road parking area top wide face no trees unobstructed flatlands below smooth airflow remote location no houses traffic its 30-to-40-minute drive Twin Cities Rochester am continually surprised number Slope fliers located Midwest Slope Soaring has long considered coastal sport caters mainly California crowd rapidly gaining reputation universal branch Soaring Beginner hints letters receive fliers new Slope Soaring ask ing few hints finding good site mak ing first flight help position also remind us little experienced basics Slope fly ing Finding good site really too difficult principle reality may turn out some what harder depending location ex perience ideal slope site would range foothills unobstructed face no trees bushes etc looks prevailing winds Actual size hill really important have flown off 5000-ft peaks off 10ft ridges What important find site faces steady relatively strong 10-30 mph winds will want find hill ridge has clear unobstructed top land ing easiest general really need take Sailplane will fly light conditions day conditions such go out vestigate possible sites cannot really de termine anything about quality site until have flown off Some best sites look nearly good vice versa As flying itself let offer couple comments should get through begin ning stages First predominant lift slope generated area about 450 top hill angle going wind commonly used technique fly back forth across face hill remaining 450 column air really difficult might sound simply location best lift reality lift just about everywhere windward side hill important thing remember get behind hill rotors develop downwind side hill have destroyed Sailplanes characteristic Slope Soaring probably difficult begin ners overcome simplest way keep out trouble imagine wall extends along top hill ridge must remain front wall stay clean air avoid downdrafts other side Once have few hours experience Slope flying will able investigate area tually youll able use advantage landing beginner place stay clear As launching will want take few steps down face hill avoid having plane thrown back behind hill Simply give plane good toss straight wind continue fly straight out until stronger lift Landing quite simple launching still difficult As beginner will probably want land going across face hill simplest surest way getting down getting caught behind hill stalling plane trying slow down too much Just fly plane slowly possible across face slightly below top hill continue lower lower until can land certainly neither pretti est nor purist way land its effective somewhat easier beginner Once have little experience will able use rotors behind hill re duced lift top hill simply lower plane down land top would rec ommend method until have logged few hours comfortable flying slope After said done best way learn fly slope simply probably saying yourself easy say being experienced Sloper just beginner beginners time us learned fly slope just doing methods beginning Sloping have helped people get sport am sure other hints could helpful neophyte know anything think might help someone little no experience slope let know will pass Slope types Another frequently asked question receive just shape slope af fects lift produced slope best way analyze lift site analyze cross sec tion slope specifically angle slope As general rule gentler slope say 300 will produce lighter lift over large area steeper slope approaching January 1989 161 Leo & MODEL BUILDING 7SERVICE RADIO CONTROL FROVUCTS carry full line Byron Originals Bob Parkerson Tom Cook Bob Violet products COD Orders Accepted 718 983-9735 128 WATCHOGUE ROAD EN SlAM 0314 Electric F ight Has Brake Lightweight 12 OLmosey hark Adjustable switching poiut guarantee easy hookup $249 ON/OFF Controller5 Power save weight aiZO Size 22x13x63 Very high efficiency 006' loss Add $105 shippiog Colitorojarosideots add 65% $163 Tss Send Check money order CoasesoithiiHIgh Sky Falaha sonsector Kansas St #9 otEaeeSan DiegoCA 92104 vertical will produce stronger lift over consider ably smaller area other words lift area slope directly related steepness slope wish fly stronger lift use up rel atively little available sky will want fly off cliff similar type slope would rather fly lighter consist ent lift will probably want fly slope quite steep Demon Tweaks have passed around modeling community some time Although theyre aimed specifically Slope Soar er hints trimming out Sailplane can immeasurable help give credit credit due believe Tweaks origi nated Pikes Peak Soaring Society newslet ter Spoiler specifically its edi tor Randy Reynolds Demon Tweak #1Make sure flying sur faces straight can done variety ways favorite simply sight down bottom surface wings stabs rear airplane suspicious surface can dis mounted double-checked flat surface such workbench flat right Trailing edges can sighted down similar manner check trueness particularly critical stab/elevator surfaces Demon Tweak #2It less fashionable days employ washout wing tips Washout trailing edge higher leading edge theory smaller chord tip would stall earlier root thus causing falloff tip another recommendation use washout since difference degree will cause erratic flightpath higher speeds such launch can check models tendency tip stall flight slowly bringing nose up until Glider stalls recovers straight ahead have washout bird good shape Demon Tweak #3Set up center-ofgravity properly Often kit plans call balanc ing spar frequently extremely conservative location will yield excellent sta bility very mediocre performance just learning fly leave ready handle performance should learn measure CG percentage wing chord able relate field experi ences percentage shop has two large blocks spruce tri angular pieces positioned halfway down block determine CG place assembled Glider triangular stock pieces un der wing root Balance Glider fore aft Measure distance triangular piece leading edge calculate per centage against full chord Generally speak ing trainers set up 30-33% Most higher-performance ships happiest 3538% Eppler 205 ships perform best 38% according pilots Use own judg ment wouldnt exceed 37% flatbottom airfoiled ships unless Top Gun caliber Demon Tweak #4Many entry-level ships observed climbing out launch shallow angles yield poor altitude Again kit manu facturers want safe suecessful therefore towhook positions extreme ward Once have learned fundamentals flying time tune towhook position CG Please think two factors insep arable generally place towhook exactly un der CG have always reliable high launches Most fliers position hook somewhat forward location perhaps / aggressive fliers looking maximum alti tude actually place hook behind CG What ever make changes several small steps starting hook ahead CG lo cation Authors note demon tweak obvi ously does apply Slope Soaring al though probably don' like admit some us occasionally some thermal flying Demon Tweak #5Most entry-level ships have narrow speed range would benefit installation turbulator strips devices tend reduce airflow separation top sur face improve performance during slow flight Studies have seen recommend two strips 10% chord measuring leading edge other 20-25% make turbulator strips Goldberg /32 color striping tape Typ ically strip laid directly top another yield bump thats repositionable decora tive tinkerers delight Bump Soaring What world Bump Soar ing Essentially Slope soaring slope thought needed large hill mountain range provide lift needed fly wrong needed create rising air enables Slope ships stay aloft something deflect change direction wind Thus need Bump Soar small ridge bump will deflect wind up wards some relatively strong winds have flown ridges small five six feet high have produced consistent lift winds 25-to-30 mph range lift does extend upwards very high strong enough maintain 25 50 ft altitude work ridge back forth What Bump Soaring does provide Slope flier opportunity polish skills learn mechanics Slope flying What type Sailplane need get volved Bump Soaring Unfortunately high-performance Racing ships just will able find lift needed unless happen flying hurricane-force winds type Sailplane best suited Bump Soaring light weight hand-launch type plane Most lighter thermal ships will able fly kind lift smaller plane better will able manage small lift area tight turns associated Bump Soaring would like try exciting diversion everyday Slope flying give Bump Soaring try very fun exhilarating way polish flying skills have opportunity travel favorite slope slope sites wanted Thanks High Performance Models presents ECL IPSE Designed Henry Piorun Former Canadian National Champion & FAI Canadian Team Member Designed Specifically FAI Pattern Flying Perform Equally Well Other AMA Classes Plug Wings rglass Belly Pan Pre-Cut Moles br Wing Joiner Tubes Ultralight Honeycomb Wingoores xfra404601 Optional Plastic Fiberglass Canopy Fiberglass Fuselage molded wing Joiner tube HIGH PERFORMANCE MODELS 9556116 st North Delta British Columbia 6Z4 Canada 604-588-0605 FINALLY Ultimate BOARD Designed & engineered WARP FREE construction HIGH-TECH MATERIAL Portable Ughtweight Conveniently Stored Large 20x78 Endgrain balsa block pin surface 314 deep Unaffected temperature humidity CASH PRICE $1 3500 Cai UPS VBA & MC 3700 BOULDER PORT ARTHUR TX 17640 409-982-8717 -F-who have sent details about favorite fly ing sites Although have received information number sites would really like have quite few put together really thorough complete directory slope sites send information favorite site please include such things prevailing winds slope gle landing area characteristics quality lift recommended flying experience directions and/or map local contact possible photo site Thanks again help project RC Scale/SruII Continued page 47 lected subtle shading keyword subtle Dont panels dont overdo Two colors will required high lights shadows Using basic air craft finish color add little white high light color little black shadow color Experiment first some scrap paper before tacking model Spray shadows first add highlights Remember Go easy dont overdo other method requires model sub structure supporting skin less scale model covered skinned somewhat flexible material does tally hide supporting substructure Major bulkheads stringers ribs spars model should located scale positions wherever pos sible Its usually good idea follow fullscale prototype structural layout anyhow scratch-building model rather totally re engineer perfectly good full-scale airplane de sign Rather using relatively stiff balsa skin typical balsa stock would firm %2 sheet plank model want use strong flexible covering material skin should flex distort small amount make internal structure visiblelike prototype Zero starved horse look usually work hard avoid just thing trying achieve case two materials have experience job nicely / ply /~ balsa / ply has very good tensile strength plus some flexibility best suited larger Scale models easiest use large pieces surfaces devoid compound curves such wing skins /16 firm balsa covering well-sanded %2 soft balsa well suited small-to-moderatesize models %- A-scale easy apply compound- high-curvature surfaces Being flexible will tend sag ripple /64 ply So depending scale model local skin strength required choose whichever best suits need case balsa skin will require layer lightweight glass cloth after attached framework will provide needed strength balsa well making surface hard enough finish standard practice edgegluing balsa sheets sanding smooth finish before attaching framework applies thin-skin structure used fi nal touch panel ripple should applied airbrush authentic look Now lets hear wrinkied-skin Zeros about target tow option least-seen interesting flight options suit able number Scale aircraft subjects target tow military training aircraft dating back Thirties pressed ser vice during WV II tow various flag sleeve targets use ground-to-air air-to-air gun nery practice An example Dreadnought version British Hawker Sea Fury fighter shown page 92 November 1988 issue MA nice plus target-tow airplanes sport interestlng distinctiveif garish color schemes ideal Scale model use sim ple reason bright color schemes flight crews wanted make absolutely sure tow aircraft could clearly seen dis tinguishable target sleeve nearsighted rookie gunnery student Though very interesting target tow simpler flight options Properly done INTRODUCING THE ELE7/JL/FE FOR 020-035-050 ELECTRICI\r SPAN 36 AREA 25T CHANNELS 2-3 ONOTH 3T FLYING WY 20 TO 30 OZ Designed built EIecSrlo Model Co 218 Oyster Ck r Land TX 77478 242-6229 Souths ingest inventory satro motors & accessories Need help wIth yow electdc ahplm orglder Ask Doe j~DuaIStrut Nose Gear Fults Tooling PO Box 95 Champaign IL 61820 NumberflistanReCe SF350 5 95 SF400 6 95 SF500 32 66901695 RF500 32 96-121595 RFY5T 321 SCSI1565 AAIosIabRGuadla OFROTlAs3116 1 seal 2995 PRODUCTS FOR THE DISCERNING MODELER Complete Line Exhaust Systems * Tuned led Tuned Pipes Headers uri Mufflers * Expansion Mufflers copter Ball Mufflers * Specialized Exhaust Systems Unsurpassed January 1989 163 Yes Virginia Santa Claus 2z Get Nearest Santas Shop 5sPeopIeof Com6ddem /mkc74 Aec Instantly removable sri-cycle gear wheels Pre-built boom landing gear sockets 8 push-roth Astro motor mount cobalt adapter Preformed leading edges knotched trailing edges Air frame 6 oz 75 ox landing gear Perfect performance 02003535 systems Maximum duration 8 glider-like motor-ofi flight characteristics ARF build 8 cover wing also completely built tail surfaces hinged . $7996 w/o gear $8695 gear ladd $3 eftipping TX res add 6% sales taxi
Edition: Model Aviation - 1989/01
Page Numbers: 42, 43, 159, 160, 161, 162, 163
QUESTIONS often appear letters arrive mail box following letter addressed Model Aviation forwarded pub lisher may concern ve flying RC planes about 4/2 years now started Goldberg Eagle 63 Over time able perform various stunts such loops barrel rolls inverted flight touch-and-go etc recently purchased built Goldberg Sky Tiger problem cant get plane turn rudder left right use rudder plane does flat turn cant get plane bank unless use ailerons banldng try level plane out rudder acts its sideslipping Say Im banking right give left rudder roll out bank Instead plane rolling left level flight plane stays bank nose goes up doing sideways flat turn tends cause loss altitude cant life figure problem out control throws set according instructions now need some experi enced advice correcting matter plane flies well except fact cant use rudder turn letter signed John Fleming Vernon NY wrote letter John rea lized problem might shared number fliers hadnt written letters Model Aviation seeking help information Its easy understand lack rolling response rudder control input would cause pilot accustomed beginner-type aircraft think problem perhaps ginner aircraft intentionally have too much dihe dral wing Consequently rudder deflected airplane starts sideslip dihedral wing generates rolling moment airplane banks direction rudder deflected So pilot thinks rudder caused bank Well suppose rudder did cause bank couldnt have happened wing dihedral So have two ways bank airplane rudder ailerons Thats good Right really Using rudder bank air plane fine long dont want turn airplane beginner airplanes dont have ailerons perform missions very well rather abrupt turns performed using rudder/wing dihedral banldng mechanism its hard tell Lift Airplane Weight Angle Attack atrim Figure 1 Ron discusses stability trim answers questions about Pattern models seemingly inexplicable things sometimes figure porlrays unique wing angle tack s needed sustain airplane level unaccelerated flight particular airspeed turns arent being done using ailerons However reason using rudder bank airplane satisfactory beginners dont tend fly airplanes inverted per form maneuvers like knife-edge flight point rolls want progress flying advanced ma neuvers must have airplane does bank rudder deflected roll airplane knife-edge apply top rud der keep nose up dont want wing dihedral cause airplane roll So benchmarks airplane Pattern flying potential absence rolling ten dency rudder deflected goal learn fly Pattern ma neuvers can bank airplane rudder reduce wing dihedral until doesnt What did tell John Fleming Sky Tiger doing just what its supposed Dont change anything Another letter arrived Wil liam Roper Englewood CO wrote long Pitching Moment Angle Attack atrim E3 Figure 2 series curves illustrtates pitching moments generated stable air plane constant airspeed several different elevator deflections E1 E2 E2 order trim plane unique elevator deflection generating zero pitching moment trim angle attack attm found Figure 1 necessary Only elevator deflectIon satisfies things 42 Model Aviation Radio Cono Sport Aerobatics Ron Van Putte Ill Sleepy Oaks Rd Ft Walton Beach FL 32548 happens pros AMA President Don Lowe examines spot cov ering missing wing Phoe nix 9 sure makes funny sound de parts during flight letter suppositions questions Wont quote whole letter just part along responses William started out like What Im trying sort out straight level unaccelerated flight Pattern airplane slowly rolled 900 either direction no other input applied airplane Im working now maintains altitude some dis tance heading changes toward direc tion roll ie pulls toward canopy RVP Obviously aircraft starts approach terra firma bank angle exceeds 450 noth ing oppose gravityno lift up about 450 bank aircraft starts almost circle since normal aircraft center-ofgravity must forward center-of-pressure some amount lest aircraft fall stall tail first circling tendency should ev ident Pattern aircraft some degree other Put another way Pattern aircraft trimmed straight unaccelerated flight will fly both upright inverted altitude change banking wings either upright inverted will produce heading change True way oppose heading change Pattern aircraft rolling maneuver judicious use rudder Which would also mean no such thing axial roll well-trimmed Pattern airplane barrel rolls altitude heading ex cursions too small detect True questions hit heart air planes really fly what differences tween trim stability Let clear air state impossible have airplane has trimmed straight level un accelerated flight rolled inverted have maintain altitude unless several complicated inter actions between engine wings fiAselage horizontal tail just right consider interaction just wings horizontal tail impossible no matter what Thats see few examples airplanes can trim just once both upright inverted flight mechanics level flight simple ten misunderstood shade tree aerody nainicists Im going bore Out skull lot equations just two simple curves will suffice get points across successful flying airplane Continued page 159 SAVE YOUR FIELD SNuF-LER muffler low cost easy install lightweight sound reducing muffler no performance penalty answer AMA muffler rule suggestions saving flying fields Meets AMA muffler rule suggestionsSNUF-LER 3 10 decIbels quieter stock mufflerMUFFLER No power loss possible 300-500 RPM increase Pat Pending Improves engine idle s better fuel economy Easily attached 25-108 stock mufflers Heat corrosion resistant Black E coat finish No special adapters required Weighs 35 oza Fits ASP BRAT ENYA FOX HP IRVINE K & B OS MAX ROYAL YS SUPER TIGRE mufflers available hobby shop ORDER DIRECT immediate shipment Check MO Visa MC CODSEND 25r STAMP accepted Add $250 UPS $205 tsr COD 6% sales taxFOR ADDITIONAL INFO Calif residentAND JTEC CATALOG January 1989 43 qqFP PUT YOURSELF AT ThE CONTROLS OF PROVEN GREAT FLYING WARDIRD almost ready fly kits have wing loadings lighter trainers very docile air land like Cub building-to-flying time very minimal fine kits together skill imagination will make plane crowd pleaser field Retracts now available Strong Light Reliable Pneumatics Idts come furnished fiberglass cowls WrIte call D&R Aircraft Mfg RO Box 23056 in TX 78736 512/288-2055 512/672-7023 Dealer Inquiries Invited $24 95 CAT NO 800 S Balsa0 Cutter5 T001~ 5 pc Masters Set 1/8 3/16 1/4 5/16 3/8 . $1698 3 pc Builders Set 3/161/4 5/16$998 Whether YOU kit builder scratch builder SQUARE CUT Tools will save time Remove stubborn die cuts cut own squares slots Made US quality machined zinc plated steel Order set today See Dealer Cataloger Order dont carry Square Cut Tools call us call well pay shipping SQUARE CUT Tools 4073 254-0516 905 N Harbor City Blvd Melbourne FL 32935 Florida Residents Dealer Distributor Inquiries Invitedadd 6% mien tax yr American Eaglet - was first light-plane receive type certificate Anorioan Eaglet carry two ooersdby LTMJ 05 motorpeople 45 horsepower ohkheosorv-Packooedintoisuros-The Eaglet complete itight system idOSA 1930s contemporary Aeronca C3 Taylor Cubs Health Parasol Pietenpol Air Camper Eaglets gentle flying characteristics reason flying schools day chose standard instructional aircraft Leisures easy-to-build scale model kit Amencan Eaglet 05 electric powered shares gentle Keiths flight itsomething hed wanted 1985 couldnt because Teds preemptive action Anyway seeing oles own design being flown Master happy humbling experience very much enjoyed particular flight Keith routinely flies oth ers models asked OK Mitch Maybe will publish Would like kit Ted sad thing about KRC meet ends good thing have en joyed continuance others hard imagine next year will mark 10th anniversary KRC Electric Fly What began dubious risky one-day affair 1980 tracted three icipants has matured two annual days sheer joy excitement happiness two days re charging friendships associations made past two days new memories ac quaintances formed year two days Electric advancement achievement shared displayed allwith having come mean over 100 participants hundreds spec tators Its heckofa flight folks have comments youd like share other Electrickers Please send themor questions SASE please ad dress given box very beginning column sincere thanks numerous folks came Fly comment favorably column appreciate interest feel ing taking time say flight characteristics full scale aircraft Scaled 18 inches-to-foot model features span 62 inches wing area 571 square inches Its lightweight structure 4041 oz flying weight allows low wing loading 104 ounces per square foot combined Leisure flight system turning 11 x 5 prop flight performance spectacular Takeoff occurs after 20 foot ground roll climb-out brisk model has thermaled moderate lift conditions Gentle landings breeze Scale details documentation included plans make scale contest winner Rsr afree copy Leisures new full color catalog send stamped self addressed business sized envelope Leisure Electrenics Inc 22971 Triton Way Unit B Lesguna Hills C4 92653 RC AerobaticsNan Putte Continued page 43 must able trimned must sta ble airplane trimmed steady level flight forces moments acting must add up zero means lift equals weight thrust equal drag no net pitching moment present two curves referred lift pitching moment curves Figure 1 shows rela tionship between lift generated given speed aircraft angle attack can see theres angle attack lift equals airplane weight airplane must angle attack maintain unaccelerated level flight airspeed chosen exam ple called trim angle attack Theres different trim angle attack another airspeed airplane angle attack higher trim angle attack will tend climb vice versa second Figure 2 curve really set curves shows pitching moment generated stable airplane given speed function airplane angle attack several elevator set tings pitching moment muat zero trim curve can pass through zero pitching moment aircrafts trim angle tack lift equals airplane weight curve labeled E2 corresponds particular elevator position summarize given airspeed angle attack elevator setting airplane will maintain unaccelerated level flight change throttle setting consume fuel trim attitude airplane will change elevator deflection required Leisure achieve will change well have prob ably noted airplanes trim changes fuel consumed flight speed changed Airplanes can designed minimize ef fects will always present degree Now what about William Ropers problem take airplane steady level flight roll 90 roll performed almost about axis line direction airplane flying call rolling about velocity vector airplane rolled 900 about axis lift wing does change However now lift countering airplanes weight fact its pointed perpen dicular Newtons laws obviously work situation airplane accelerates direction perpendicular wings downward well So much mystery What happens airplane rolled less 45 ally same forces present airplane rolled 90 effect reduced Consequently air plane will start gentle turn due unopposed part lift generated wing airplanes descent reduced because substan tial fraction lift available counter airplanes weight Consequently airplane will enter descending torn So does banking produce heading change Yes suggestion made William Roper way oppose heading change rolling maneuver judicious use rudder What suggested true However dont know anyone fast enough right amount rudder counter heading changes good news takes time airplanes heading change very much since supposed perform three rolls five seconds heading changes dont have January 1989 159 New Leisure introduces electric scale American Eaglet responding advertisers mention thatyou read about ModelAviation lot time develop allegation nobody does axial roll true lift force being developed wings rotates around airplane rolls air plane accelerates direction unop posed force means path air plane cannot straight Obviously some air planes better others performing axial rolls barrel roll degree RC Slope Soaring/Triebes Continued page 45 ships Can imagine what would say someone claimed powered plane fully acrobatic asymmetrical wing no rud der same goes Slope Soarers snap rolls four-point rolls clean hammerheads other maneuvers must have rudder side outside maneuvers have same size shape symmetrical alrfoil pretty much necessity almost no Slope kits fully acrobatic writers like yourself keep sisting todays crop planes like Savage its progeny SR-7 forth good are fully aerobatic think will see new breed Another thing will further good designs contests CD thinks nothing call ing outside loops inverted flight rolling circles one-and-a-half snaps vertical eights Jef makes some very good points am sure Slope Soaring continues grow MINI-JET SERIES planes feature balsa construction Designed intermediate flyer in A4 mind will accept 20-25 size engine fuse rear exhaust engine exceptional Skyhawk performancel thrill jet heesles ducted fan $4000 &H Proud Bird deeignad meet OSPRA Formula 120 rules 114 scale model will accept 60-120 ci size engines Epoxy glees fueelage foam wing construction Full kit $150 Semi-kit also available Inn woodi $i25 Please add $10 S&H F-20 Tlgenhark Send check money order COD add $300 esidents add 6% sales tsx Dart ExperImental two-place full size alrr5ft Top Turkey Formula 1 $85$5S&H PARRISH AIRCRAFTScale Models ll25SW49thTer Plantation FL33317 will see new designs emerging number hoped will fully acrobatic Jef also looking some information help him evaluate relative merits different sym metrical airfoils Slope Soaring Aerobatics Any information can get subject would greatly appreciated Jefs name sounds familiar some probably because principal people involved developing Apple Macin tosh computer Jef also wrote program Micro soft Basic Mac will calculate coordi nates display picture NACA fourdigit airfoil appears Martin Hollmanns book Modem Aircraft Design very inter esting us designer types play would like listing program send SASE two stamps please Spitfire Slope LeRoy Satterlee Wa terloo IA sent couple photos beautiful Spitfire Mk XII built John Lupperger Plans Service plans what has say about designed 25-size power plane orig inally did build light leave off engine finished plane flown aile ron elevator no rudder wing loading 925 oz per sq ft made slow est flying Spitfire anyone could remember having seen addition about 10 oz lead picked up flying speed plane flew much solidly experiments will continue re turn hill later year ever build another Spitfire Ill build heavier use thin ner airfoil some kind get speed up further Power Slope Scale fun di version recommend everyone LeRoy flying buddies travel two-and-ahalf hours southeastern Wisconsin Slope flying sald Slope fliers dedi cated Four group including LeRoy have completed LSF Level 5 eight-hour slope flights Superslope Tom Rent member fleer Minnesota RC Soaring Society gives further evidence Slope Soaring alive well Midwest club relatively large approaching 100 members have recently discovered 160 Model Aviation CA MASK CA glue works wonders building models right Unfortunately gives enough fumes knock vulture off carcass modelers have suffered medical problems after inhaling CA fumes take chances special vapor respirator filters CA fumesl soft face mask adjustable straps comfortably fits face sizes easy breathing valve allows prolonged use providing dependable filtering concentrations up 1000 PPM though rugged industrial mask light weight elimi nate fatigue Dont get gassed CA Get protected Order CA Mask today Just $1247 shipping cheaper hospital visit Money order Master Charge Visa include expiration date check allow 20 days clear Sorry no CODs Pelican Enterprises 2540 RIDGE ROAD LANSING ILLINOIS 60438 P S Send catalog modelers safety supplies 305 581-4477 Latest Japanese Pattern Design Designed & Flown TOP Japanese Pilot Suitable FAI AMA Classes tCa5a FberRedewd EtrexyiSasa FuaabgaSpa, -57 wing Area 750 eq 2 Fe 5e Siesied Cake FbarRakfrexedUkeLld HxeepaenA PraitWhrs 3Fadxy5traahd a5patle& raesrieeke 41W errewarhised hedre ed 5 Pawt FeaeI Now Offered Super Deluxe Pm-Built Kit $45000 Completely Finished Model Call info & pricing VISA& MASTERCARD WELCOME Pteae add $t5mt Srr& Hadna inidaadd &5%.15550dntwa&AdaCewayNPhone408298-0311 FAX#408298-6538 IA NEW ELECTRIC Fly .. great stand-way-off scale fun ship designed 05 electric power can perform take-offs touch goes aerobatics beauty yet enjoy docile slow flight easy landings Quick easy build kit includes pre cut fuselage sides tail feathers small parts hardware complete rolled plans step-by-step instructions formed landing gear windshield Electro-Combo includes kit DSC 075 Hyperthrust motor fused switch harness Tamiya connector propeller adaptor 8/4 fiberglass propeller 40 Span 275 Sq area 32 oz flying weight flat bottom airfoil rudder elevator motor add ailerons too SPECIAL COMBO PRICE $4795 IPAVEY675 YSTEMSWEST CHESTEF PA 193& BASIC KIT $244oRRATloN215~ wonderful world Slope Soaring Although true Midwest flat some areas blessed beautiftil grass-covered hills provided retreating glaciers site Superslope call Nerstrand MN perfect come Picture Steep grass-covered face road parking area top wide face no trees unobstructed flatlands below smooth airflow remote location no houses traffic its 30-to-40-minute drive Twin Cities Rochester am continually surprised number Slope fliers located Midwest Slope Soaring has long considered coastal sport caters mainly California crowd rapidly gaining reputation universal branch Soaring Beginner hints letters receive fliers new Slope Soaring ask ing few hints finding good site mak ing first flight help position also remind us little experienced basics Slope fly ing Finding good site really too difficult principle reality may turn out some what harder depending location ex perience ideal slope site would range foothills unobstructed face no trees bushes etc looks prevailing winds Actual size hill really important have flown off 5000-ft peaks off 10ft ridges What important find site faces steady relatively strong 10-30 mph winds will want find hill ridge has clear unobstructed top land ing easiest general really need take Sailplane will fly light conditions day conditions such go out vestigate possible sites cannot really de termine anything about quality site until have flown off Some best sites look nearly good vice versa As flying itself let offer couple comments should get through begin ning stages First predominant lift slope generated area about 450 top hill angle going wind commonly used technique fly back forth across face hill remaining 450 column air really difficult might sound simply location best lift reality lift just about everywhere windward side hill important thing remember get behind hill rotors develop downwind side hill have destroyed Sailplanes characteristic Slope Soaring probably difficult begin ners overcome simplest way keep out trouble imagine wall extends along top hill ridge must remain front wall stay clean air avoid downdrafts other side Once have few hours experience Slope flying will able investigate area tually youll able use advantage landing beginner place stay clear As launching will want take few steps down face hill avoid having plane thrown back behind hill Simply give plane good toss straight wind continue fly straight out until stronger lift Landing quite simple launching still difficult As beginner will probably want land going across face hill simplest surest way getting down getting caught behind hill stalling plane trying slow down too much Just fly plane slowly possible across face slightly below top hill continue lower lower until can land certainly neither pretti est nor purist way land its effective somewhat easier beginner Once have little experience will able use rotors behind hill re duced lift top hill simply lower plane down land top would rec ommend method until have logged few hours comfortable flying slope After said done best way learn fly slope simply probably saying yourself easy say being experienced Sloper just beginner beginners time us learned fly slope just doing methods beginning Sloping have helped people get sport am sure other hints could helpful neophyte know anything think might help someone little no experience slope let know will pass Slope types Another frequently asked question receive just shape slope af fects lift produced slope best way analyze lift site analyze cross sec tion slope specifically angle slope As general rule gentler slope say 300 will produce lighter lift over large area steeper slope approaching January 1989 161 Leo & MODEL BUILDING 7SERVICE RADIO CONTROL FROVUCTS carry full line Byron Originals Bob Parkerson Tom Cook Bob Violet products COD Orders Accepted 718 983-9735 128 WATCHOGUE ROAD EN SlAM 0314 Electric F ight Has Brake Lightweight 12 OLmosey hark Adjustable switching poiut guarantee easy hookup $249 ON/OFF Controller5 Power save weight aiZO Size 22x13x63 Very high efficiency 006' loss Add $105 shippiog Colitorojarosideots add 65% $163 Tss Send Check money order CoasesoithiiHIgh Sky Falaha sonsector Kansas St #9 otEaeeSan DiegoCA 92104 vertical will produce stronger lift over consider ably smaller area other words lift area slope directly related steepness slope wish fly stronger lift use up rel atively little available sky will want fly off cliff similar type slope would rather fly lighter consist ent lift will probably want fly slope quite steep Demon Tweaks have passed around modeling community some time Although theyre aimed specifically Slope Soar er hints trimming out Sailplane can immeasurable help give credit credit due believe Tweaks origi nated Pikes Peak Soaring Society newslet ter Spoiler specifically its edi tor Randy Reynolds Demon Tweak #1Make sure flying sur faces straight can done variety ways favorite simply sight down bottom surface wings stabs rear airplane suspicious surface can dis mounted double-checked flat surface such workbench flat right Trailing edges can sighted down similar manner check trueness particularly critical stab/elevator surfaces Demon Tweak #2It less fashionable days employ washout wing tips Washout trailing edge higher leading edge theory smaller chord tip would stall earlier root thus causing falloff tip another recommendation use washout since difference degree will cause erratic flightpath higher speeds such launch can check models tendency tip stall flight slowly bringing nose up until Glider stalls recovers straight ahead have washout bird good shape Demon Tweak #3Set up center-ofgravity properly Often kit plans call balanc ing spar frequently extremely conservative location will yield excellent sta bility very mediocre performance just learning fly leave ready handle performance should learn measure CG percentage wing chord able relate field experi ences percentage shop has two large blocks spruce tri angular pieces positioned halfway down block determine CG place assembled Glider triangular stock pieces un der wing root Balance Glider fore aft Measure distance triangular piece leading edge calculate per centage against full chord Generally speak ing trainers set up 30-33% Most higher-performance ships happiest 3538% Eppler 205 ships perform best 38% according pilots Use own judg ment wouldnt exceed 37% flatbottom airfoiled ships unless Top Gun caliber Demon Tweak #4Many entry-level ships observed climbing out launch shallow angles yield poor altitude Again kit manu facturers want safe suecessful therefore towhook positions extreme ward Once have learned fundamentals flying time tune towhook position CG Please think two factors insep arable generally place towhook exactly un der CG have always reliable high launches Most fliers position hook somewhat forward location perhaps / aggressive fliers looking maximum alti tude actually place hook behind CG What ever make changes several small steps starting hook ahead CG lo cation Authors note demon tweak obvi ously does apply Slope Soaring al though probably don' like admit some us occasionally some thermal flying Demon Tweak #5Most entry-level ships have narrow speed range would benefit installation turbulator strips devices tend reduce airflow separation top sur face improve performance during slow flight Studies have seen recommend two strips 10% chord measuring leading edge other 20-25% make turbulator strips Goldberg /32 color striping tape Typ ically strip laid directly top another yield bump thats repositionable decora tive tinkerers delight Bump Soaring What world Bump Soar ing Essentially Slope soaring slope thought needed large hill mountain range provide lift needed fly wrong needed create rising air enables Slope ships stay aloft something deflect change direction wind Thus need Bump Soar small ridge bump will deflect wind up wards some relatively strong winds have flown ridges small five six feet high have produced consistent lift winds 25-to-30 mph range lift does extend upwards very high strong enough maintain 25 50 ft altitude work ridge back forth What Bump Soaring does provide Slope flier opportunity polish skills learn mechanics Slope flying What type Sailplane need get volved Bump Soaring Unfortunately high-performance Racing ships just will able find lift needed unless happen flying hurricane-force winds type Sailplane best suited Bump Soaring light weight hand-launch type plane Most lighter thermal ships will able fly kind lift smaller plane better will able manage small lift area tight turns associated Bump Soaring would like try exciting diversion everyday Slope flying give Bump Soaring try very fun exhilarating way polish flying skills have opportunity travel favorite slope slope sites wanted Thanks High Performance Models presents ECL IPSE Designed Henry Piorun Former Canadian National Champion & FAI Canadian Team Member Designed Specifically FAI Pattern Flying Perform Equally Well Other AMA Classes Plug Wings rglass Belly Pan Pre-Cut Moles br Wing Joiner Tubes Ultralight Honeycomb Wingoores xfra404601 Optional Plastic Fiberglass Canopy Fiberglass Fuselage molded wing Joiner tube HIGH PERFORMANCE MODELS 9556116 st North Delta British Columbia 6Z4 Canada 604-588-0605 FINALLY Ultimate BOARD Designed & engineered WARP FREE construction HIGH-TECH MATERIAL Portable Ughtweight Conveniently Stored Large 20x78 Endgrain balsa block pin surface 314 deep Unaffected temperature humidity CASH PRICE $1 3500 Cai UPS VBA & MC 3700 BOULDER PORT ARTHUR TX 17640 409-982-8717 -F-who have sent details about favorite fly ing sites Although have received information number sites would really like have quite few put together really thorough complete directory slope sites send information favorite site please include such things prevailing winds slope gle landing area characteristics quality lift recommended flying experience directions and/or map local contact possible photo site Thanks again help project RC Scale/SruII Continued page 47 lected subtle shading keyword subtle Dont panels dont overdo Two colors will required high lights shadows Using basic air craft finish color add little white high light color little black shadow color Experiment first some scrap paper before tacking model Spray shadows first add highlights Remember Go easy dont overdo other method requires model sub structure supporting skin less scale model covered skinned somewhat flexible material does tally hide supporting substructure Major bulkheads stringers ribs spars model should located scale positions wherever pos sible Its usually good idea follow fullscale prototype structural layout anyhow scratch-building model rather totally re engineer perfectly good full-scale airplane de sign Rather using relatively stiff balsa skin typical balsa stock would firm %2 sheet plank model want use strong flexible covering material skin should flex distort small amount make internal structure visiblelike prototype Zero starved horse look usually work hard avoid just thing trying achieve case two materials have experience job nicely / ply /~ balsa / ply has very good tensile strength plus some flexibility best suited larger Scale models easiest use large pieces surfaces devoid compound curves such wing skins /16 firm balsa covering well-sanded %2 soft balsa well suited small-to-moderatesize models %- A-scale easy apply compound- high-curvature surfaces Being flexible will tend sag ripple /64 ply So depending scale model local skin strength required choose whichever best suits need case balsa skin will require layer lightweight glass cloth after attached framework will provide needed strength balsa well making surface hard enough finish standard practice edgegluing balsa sheets sanding smooth finish before attaching framework applies thin-skin structure used fi nal touch panel ripple should applied airbrush authentic look Now lets hear wrinkied-skin Zeros about target tow option least-seen interesting flight options suit able number Scale aircraft subjects target tow military training aircraft dating back Thirties pressed ser vice during WV II tow various flag sleeve targets use ground-to-air air-to-air gun nery practice An example Dreadnought version British Hawker Sea Fury fighter shown page 92 November 1988 issue MA nice plus target-tow airplanes sport interestlng distinctiveif garish color schemes ideal Scale model use sim ple reason bright color schemes flight crews wanted make absolutely sure tow aircraft could clearly seen dis tinguishable target sleeve nearsighted rookie gunnery student Though very interesting target tow simpler flight options Properly done INTRODUCING THE ELE7/JL/FE FOR 020-035-050 ELECTRICI\r SPAN 36 AREA 25T CHANNELS 2-3 ONOTH 3T FLYING WY 20 TO 30 OZ Designed built EIecSrlo Model Co 218 Oyster Ck r Land TX 77478 242-6229 Souths ingest inventory satro motors & accessories Need help wIth yow electdc ahplm orglder Ask Doe j~DuaIStrut Nose Gear Fults Tooling PO Box 95 Champaign IL 61820 NumberflistanReCe SF350 5 95 SF400 6 95 SF500 32 66901695 RF500 32 96-121595 RFY5T 321 SCSI1565 AAIosIabRGuadla OFROTlAs3116 1 seal 2995 PRODUCTS FOR THE DISCERNING MODELER Complete Line Exhaust Systems * Tuned led Tuned Pipes Headers uri Mufflers * Expansion Mufflers copter Ball Mufflers * Specialized Exhaust Systems Unsurpassed January 1989 163 Yes Virginia Santa Claus 2z Get Nearest Santas Shop 5sPeopIeof Com6ddem /mkc74 Aec Instantly removable sri-cycle gear wheels Pre-built boom landing gear sockets 8 push-roth Astro motor mount cobalt adapter Preformed leading edges knotched trailing edges Air frame 6 oz 75 ox landing gear Perfect performance 02003535 systems Maximum duration 8 glider-like motor-ofi flight characteristics ARF build 8 cover wing also completely built tail surfaces hinged . $7996 w/o gear $8695 gear ladd $3 eftipping TX res add 6% sales taxi