This reliable system offers advantages merit individual experimentation U Dick Mathis LANDING GEARS have posed problems aircraft designers beginning Wright brothers solved problem leaving landing gear ground Subsequent designers have yet escape fact airplanes useful have drag around 100 percent time something use 5 percent time Since landing gears interface ground rather air shape requirements have always decidedly unaerodynamic may account revulsion designers feel process building aircraft em phasizes dilemma example breezing along Hot Stuffing beautiful light balsa spruce pieces other suddenly come realm music wire nuts bolts solder plywood etc have use different glue tools attach some heavy ungainly landing gear sleek device Full-scale manufacturers have same problem Most use landing gear assemblies fabricated other com panies have special tools tech nology required model airplane manufacturers suffer example five years before company acquired machinery knowledge necessary properly manufacture kit designs landing gears Until simply manu factured designs regard suspicion anyone professes really like landing gears Besides inherently repulsive phys ical attributes landing gears sorts bad things air flow slow aircraft down foul up orderly flow air around wing fuselage 46 Model Aviation novelty wave future Retracted view shows close me gear set t reauce moments inertia wing Adjusto-Jig gear has provision adjustment travel wheel well Gear fairings shown aluminum templates laminated basswood fairings made 4This prototype system installed old ship day no attempt seal off wing air flow oil Tests taped-over openings indicated no per formance differentialbut thats gospel siphon off precious power lowest speeds essence landing gears irritate air air responds making aircraft fly worse Finally would unrealistic especially since discussing modeling event CL Stunt top fliers design latest winners around paint scheme going use failed men tion landing gears look bad Retracts two good things 1 make aircraft efficient aerody namically 2 better aesthet ically other hand three bad things 1 make construction difficult 2 heavier 3 less reliable Therefore fans playing percentages will see no need mess up good safe thing will read no further Gamblers others like see things happen will stay After studying situation since 1967 building nothing finally got work retracts stunt wintertesting redesigningand have concluded work worth effort Pri marily will describe prototype sys tem flying conventional ship designed originally fixed gears second system new un tested aircraft designed specifically retracts 78 contest season will fully described after proves itself Next will describe what effects re tracts have finally discuss pros cons retracts try predict role future stunt System should state first second third re tract system stunt Nevertheless probably first competitive system objective developing retracts have retracts own sake rather beat people big contests would enjoy having fun watching gear go up down will simple install system profile kit design system blends V2A RC components clockwork timer used free fighters com ponents obtainable commercially system costs $25 Seelig timer $13 Adjusto-Jig retracting gear few dollars other devises pushrods springs junk described shortly total costs less finish new ship big thing makes retracts pos sible us sleep milling machine foot bed long-awaited introduction re tracts RC namely Adjusto-Jig brand beefier others appeared about same time stunter needs I/s music wire gears handle smoothlysmaller ones vibrate landPROTOTYPE GEAR RETRACTION SYSTEM Rear aircraft Larger spring least ten times powerful return spring Size springs depends weight wheels drag system line#l 1 Top View Outward push retracts gear inward pull lowers Small Veco bellcrank Adjusto-jig l/2A retracts Try keep wheels light practical ditto fairings retract spring will have too powerful I Timerreleasesne #1 after 15 - seconds retract gearre leases line #2 about 360 se conds lower gear lines Sullivan CO braided steel line #2 i Larger spring provides retrac tion force pulling aft bellcrank takeoff position line #1 overrides sprinq lock ing wheels down position timer releases line #2 tension larger spring lost Once both lines release weak small spring returns system its starting position allowing wheels come down gravity 1/16 MW pushrod 60 Bend short leg bellcrank down let spring cables clear pushrods End small spring attaches airframe Fulcrum reverses pull direction line #1 comes gear kit August1978 47 Construction Chizler gear bay blocks off openings aerodynamic cleanliness stop oil seepage Adiusto-Jig gear relies gravity extend end flight lock automatically Unit weight 1-5/8 oz. including wire some would needed anyway ingand Adjusto-Jig gear has /s wire doubt however whether smoothly flown stunter needs much strength gear mount area RC Adjusto-Jig gear mechanism adequate new gear systems fer nose gears too Seelig timer used made Ger famous free fighter same name precision clockwork affair thoroughly overengineered lots bearing surfaces other good things make timers reliable universal timer used FAI free-flight people over world rarely fails although can readily set incorrectly cause interesting things happen since capable doing four things once Free fighters use four functions like 1 67 seconds shut off engine 2 69 seconds actuate rudder 3 71 seconds actuate elevator glide 4 185 seconds dethermalize functions can set occur time over period min utes necessary use functions mechanism makes model roll takeoff timer initiates retract cycle after about 15 seconds 2 laps gears go up instantly noiselessly have never detected trim change occurs may matter instant correction being made pilot unconsciouslythe same gusts turbulence pattern completed gear retracted timer releases retract spring within about 20 seconds other 20 seconds engine run left gear comes down motor quits fuel exhaustion plane lands will have already noticed possibility shutting engine off timer will especially nice flying under ridiculous FAI time limit slow pattern leaves very little time avoid overrun Effects There superstition ignorance about stunt design other event theories am hearing explain retracts wont help things happen revolving drum spiral groove cut its side wire hook fits groove works its way top spiral groove rotates wire eventually escapes drum releases whatever lines have connected sort mousetrap set-up Short duration functions can done three-notched discs revolve axle separate drum impos sible explain timer unless can see work Seelig Type FiG may ob tained $2500 Doug Galbreath 707 Second St Davis CA 95616 Watch top FAI man work day will have no reservations about whether Seelig timer will stand up stunt aircraft ships launcher stooge actuates timer lets 48 Model Aviation Heart system Seelig FF timer Spiral-grooved disk runs over 6 mm desired three flat disks notches provide short duration functions less 30 sec Button-like plunger held down wire clip on-off switch Weight 1-3/8 oz length 2-1/2 nIzer ~ ... h~ ...dnism may replaced Rectangular areas covered screw-mounted 005 aluminum sheet Springs actuation lines located aft section fuselage Actuation lines taped painting Cosmetic advantages ot retracts obvious opportunities tor aesigners oeveiop new styles aircraft designs Tail wheel could retracted Small wing skids mounted wing tips cowl bottom would protect ship abrasion should malfunction occur dramatic deceleration 4 Level flight smoother less tendency hunt up down 5 Gusts traversed easily 6 There no increased tendency wind-up gain speed wind doing consecutive loops earthshaking con sider what better penetration means someone like loves slow patterns flown light airplanes relatively little power Remember turbulence always killed light slow ones retracts help cut through turbulence can go lighter slower yet Obviously believe being able fly slowly secret ultimate pattern ap pears retracts will make slow flying practical under wide range conditions Impact Stunt going take couple years us rethink stunt de sign use retracts full advantage meantime lot will depend Nationals year next will also accelerate dominance retracts big-time flier converts use soon know def initely although system Initially will see few retract really getting clever think am dealing facts theory although observations based flying impressions alone may 100 percent accurate can think no category indoor microfilm rubber-powered RC pattern has experienced improvement due increased aerodynamic efficiency effects retracted gear stunt model subtleno big thing happens total little improvements better-flying aircraft better pat tern no stretch imagination does retracted gear make aircraft fly worse well-known flier has suggested 1 Penetration wind low speed seems better overhead eights 2 Wobble tip roll hinging Dutch roll lateral oscillation choose term seem reduced 3 Corner exits cleaner less ships fly better best rigid gear ones will take can re member long took auto-stab auto-rudder set-ups dominate FAI free flight several years possible win non-automated flying surfaces because sheer weight numbers fre quent malfunctioning failure prop erly utilize automation producing com pletely new designs rather applying new devices existing designs Now top fliers use auto-surfaces same process occurred RC pattern rat racing hand-launched glider events have experienced dramatic transitions caused single technological innovation going take least contest Continued page 100 August1978 49 Prototype system used smaller Seelig Mini-Combo timer used Nordic gliders Crude trip wires necessary because timer Stripped down Nordic line shown lock system down prior takeoff other release main tension anrina axtnninn Combination springs main spring between Nyrods supplies power retraction smaller spring returns system extension made once tension big spring released timer Picture suggests system light weight should reliable Specifically designed retracts authors new Chizier weighs 39 ounces complete Timer installa tion nose rubber mounted cushion against vibration Grumman Guardian Class Carrier XTB3F28/T\CLD-102 IBy IgCatalog25cRag Edwards IMODERNISTIC MODELSj PO BOX 6974 ALBUQ NM 87197 derwritten TRW Thompson Trophy Check out Dennis Norman 13885 Edgewater Dr Lakewood OH 44107 club Flying Aces oriented plans alone worth several times ante neat source recent issue con cerns 45 b/w 8 x 10 prints available US Government Printing Office Washington DC $435 Pioneer USAF types jet-age subjects Besides helpful hints tips 3-view drawings plans included super Book Buy Month Anyone really serious about FF Scale can no better check William McCombs book Flying Improving Scale Model Airplanes Some us learn hard way through thousands trial-and-error flights Some better suited applying well-presented theoretical approaches latter persuasion $695 plus $145 parcel post will bring information will probably ever need Send MAN North Broad way White Plains NY 10601 Maybe club would like give copy worst crash next meet FAC Nats contest year interested FF scale almost Nine scale events over weekend July 15 16 will draw top scalers East Coast site Johnsville NAS Philadelphia spirit Flying Aces party Saturday evening promises unite kindred souls far wide See Proxies OK have some mind will agree fly $300 advance registration Lin Riechel 3301 Cindy Lane Erie PA 16506 Bill Warner 423-C San Vicente Blvd Santa Monica CA 90402 Retracts/Mathis continued page 49 season perfect new routines needed preparing model between flights Add winding timer setting little trigger mechanisms re fueling routine tense tired opens door foul-ups Another thing added psychological stress flying important pattern know ing years work can ruined gear doesnt come down nice thing about single part made unobtanium everyone can use retracts want just buy parts put Ideas Further Development other timers retractable gear set-ups available applications other contest stunt system situations utmost durability reliability crucial Tatone dether malizer timer will cheaper lighter easier install Tatone fuel shut-off timer will run long enough about 30 seconds pneumatic timers such Austincrafts accurate over pe riod long stunt pattern might used trigger retract cycle con junction some other device lower gear such pressure valve off muffler pure thrill seeing gear something sometimes before land simple dethermalizer fuse could used cant say what other brands landing gears will work although types compact light enough biggest hassle have concerns install ing gear way retracts flush airfoil bottom yet still have enough forward angle give proper wheel location stunters wing bottom highly cambered leading edge opposed RCs conventional two-wheel wing-mounted gear will re quire lot meticulous fitting give clean exterior surface solution use tricycle gear two wing gears can mounted section airfoil aft high point critical airflow pattern features find exciting about retracts realism would very easy rig simple gear attached fuselage swiveled back flush against wing would efficient attractive original idea 1967 have two sets land ing gearsone went up came down because couldnt figure out lock first gear came back down system would illegal under present rules state plane must land takeoff gear primary motives de veloping retracts provide taller landing gears prop clearance would allow use large diameter props destroying sleek ap product review product review product review pearance design still believe props ultimate key further progress stunt ability use larger props alone would justify use retracts Elias Airsport/M ever continued page 51 Add 1/16 aluminum tubes wheel bear ings Make cabane struts 1/64 ply wood install fuselage Tail Surfaces Make cardboard patterns outline stabilizer fin rudder Soak strips 1/32 sq hard balsa bass wood boiling waterform around cardboard pattern pins Let dry thor oughly pin over drawings stall 1/20 balsa spars ribs little trick learned keep tail surfaces warping Make frame out 1 X 2 lumber big enough glue about quarter sheet Japanese tissue water doped dry give coat thinned nitrate dope 50/50 dope thinner dry remove form cover fin rudder Put AIRSPORT sign side fuselage taping piece colored Japanese tissue over plans painting sign white nitrate dope Make two signs side fuselage Carefully position paper AIRSPORT sign over fuselage proper place glue framework dope Glue another piece white Japanese tissue frame water dope give coat nitrate dope Mix Floquil silver railroad paint nitrate dope pour off thinner top Floquil paint use thick aluminum bottom bot tle Spray lightly white paper airbrushjust enough give silver color Now cover horizontal stabilizer elevators doped paper Wings Make cardboard templates wing tip trailing edge wing Soak strips 1/32 hard balsa basswood hot water form around trailing edge wing tip patterns same did around tail surfaces Make up sliced ribs using metal template top bottom ribs Pin wing tip trailing edge leading edge plans install top section sliced ribs Remove wings plans install bottom ribs Notch leading edge trailing edge crack form correct dihedral angle Make 1/32 balsa spars stick correct positions gluing Titebond glue Make up spar splices 1/32 balsa glue spars correct dihedral angle Glue fillers between ribs wing strut center-section strut locations gave wings about 1/16 washout trailing edge 1/16 higher leading edge Cover lightweight white Japanese tissue water dope give coat thinned-out nitrate dope Spray wings silverthe same used 100 ModelAviation product review product review product review Seen Toledo li-lb McDonnellDoug las F-15 Duane Johnson will longawaited kit World Engines two duct ed fan 40s Ship can fly engine World Engines 8960 Rossash Ave Cincinnati ON 45236
Edition: Model Aviation - 1978/08
Page Numbers: 46, 47, 48, 49, 100
This reliable system offers advantages merit individual experimentation U Dick Mathis LANDING GEARS have posed problems aircraft designers beginning Wright brothers solved problem leaving landing gear ground Subsequent designers have yet escape fact airplanes useful have drag around 100 percent time something use 5 percent time Since landing gears interface ground rather air shape requirements have always decidedly unaerodynamic may account revulsion designers feel process building aircraft em phasizes dilemma example breezing along Hot Stuffing beautiful light balsa spruce pieces other suddenly come realm music wire nuts bolts solder plywood etc have use different glue tools attach some heavy ungainly landing gear sleek device Full-scale manufacturers have same problem Most use landing gear assemblies fabricated other com panies have special tools tech nology required model airplane manufacturers suffer example five years before company acquired machinery knowledge necessary properly manufacture kit designs landing gears Until simply manu factured designs regard suspicion anyone professes really like landing gears Besides inherently repulsive phys ical attributes landing gears sorts bad things air flow slow aircraft down foul up orderly flow air around wing fuselage 46 Model Aviation novelty wave future Retracted view shows close me gear set t reauce moments inertia wing Adjusto-Jig gear has provision adjustment travel wheel well Gear fairings shown aluminum templates laminated basswood fairings made 4This prototype system installed old ship day no attempt seal off wing air flow oil Tests taped-over openings indicated no per formance differentialbut thats gospel siphon off precious power lowest speeds essence landing gears irritate air air responds making aircraft fly worse Finally would unrealistic especially since discussing modeling event CL Stunt top fliers design latest winners around paint scheme going use failed men tion landing gears look bad Retracts two good things 1 make aircraft efficient aerody namically 2 better aesthet ically other hand three bad things 1 make construction difficult 2 heavier 3 less reliable Therefore fans playing percentages will see no need mess up good safe thing will read no further Gamblers others like see things happen will stay After studying situation since 1967 building nothing finally got work retracts stunt wintertesting redesigningand have concluded work worth effort Pri marily will describe prototype sys tem flying conventional ship designed originally fixed gears second system new un tested aircraft designed specifically retracts 78 contest season will fully described after proves itself Next will describe what effects re tracts have finally discuss pros cons retracts try predict role future stunt System should state first second third re tract system stunt Nevertheless probably first competitive system objective developing retracts have retracts own sake rather beat people big contests would enjoy having fun watching gear go up down will simple install system profile kit design system blends V2A RC components clockwork timer used free fighters com ponents obtainable commercially system costs $25 Seelig timer $13 Adjusto-Jig retracting gear few dollars other devises pushrods springs junk described shortly total costs less finish new ship big thing makes retracts pos sible us sleep milling machine foot bed long-awaited introduction re tracts RC namely Adjusto-Jig brand beefier others appeared about same time stunter needs I/s music wire gears handle smoothlysmaller ones vibrate landPROTOTYPE GEAR RETRACTION SYSTEM Rear aircraft Larger spring least ten times powerful return spring Size springs depends weight wheels drag system line#l 1 Top View Outward push retracts gear inward pull lowers Small Veco bellcrank Adjusto-jig l/2A retracts Try keep wheels light practical ditto fairings retract spring will have too powerful I Timerreleasesne #1 after 15 - seconds retract gearre leases line #2 about 360 se conds lower gear lines Sullivan CO braided steel line #2 i Larger spring provides retrac tion force pulling aft bellcrank takeoff position line #1 overrides sprinq lock ing wheels down position timer releases line #2 tension larger spring lost Once both lines release weak small spring returns system its starting position allowing wheels come down gravity 1/16 MW pushrod 60 Bend short leg bellcrank down let spring cables clear pushrods End small spring attaches airframe Fulcrum reverses pull direction line #1 comes gear kit August1978 47 Construction Chizler gear bay blocks off openings aerodynamic cleanliness stop oil seepage Adiusto-Jig gear relies gravity extend end flight lock automatically Unit weight 1-5/8 oz. including wire some would needed anyway ingand Adjusto-Jig gear has /s wire doubt however whether smoothly flown stunter needs much strength gear mount area RC Adjusto-Jig gear mechanism adequate new gear systems fer nose gears too Seelig timer used made Ger famous free fighter same name precision clockwork affair thoroughly overengineered lots bearing surfaces other good things make timers reliable universal timer used FAI free-flight people over world rarely fails although can readily set incorrectly cause interesting things happen since capable doing four things once Free fighters use four functions like 1 67 seconds shut off engine 2 69 seconds actuate rudder 3 71 seconds actuate elevator glide 4 185 seconds dethermalize functions can set occur time over period min utes necessary use functions mechanism makes model roll takeoff timer initiates retract cycle after about 15 seconds 2 laps gears go up instantly noiselessly have never detected trim change occurs may matter instant correction being made pilot unconsciouslythe same gusts turbulence pattern completed gear retracted timer releases retract spring within about 20 seconds other 20 seconds engine run left gear comes down motor quits fuel exhaustion plane lands will have already noticed possibility shutting engine off timer will especially nice flying under ridiculous FAI time limit slow pattern leaves very little time avoid overrun Effects There superstition ignorance about stunt design other event theories am hearing explain retracts wont help things happen revolving drum spiral groove cut its side wire hook fits groove works its way top spiral groove rotates wire eventually escapes drum releases whatever lines have connected sort mousetrap set-up Short duration functions can done three-notched discs revolve axle separate drum impos sible explain timer unless can see work Seelig Type FiG may ob tained $2500 Doug Galbreath 707 Second St Davis CA 95616 Watch top FAI man work day will have no reservations about whether Seelig timer will stand up stunt aircraft ships launcher stooge actuates timer lets 48 Model Aviation Heart system Seelig FF timer Spiral-grooved disk runs over 6 mm desired three flat disks notches provide short duration functions less 30 sec Button-like plunger held down wire clip on-off switch Weight 1-3/8 oz length 2-1/2 nIzer ~ ... h~ ...dnism may replaced Rectangular areas covered screw-mounted 005 aluminum sheet Springs actuation lines located aft section fuselage Actuation lines taped painting Cosmetic advantages ot retracts obvious opportunities tor aesigners oeveiop new styles aircraft designs Tail wheel could retracted Small wing skids mounted wing tips cowl bottom would protect ship abrasion should malfunction occur dramatic deceleration 4 Level flight smoother less tendency hunt up down 5 Gusts traversed easily 6 There no increased tendency wind-up gain speed wind doing consecutive loops earthshaking con sider what better penetration means someone like loves slow patterns flown light airplanes relatively little power Remember turbulence always killed light slow ones retracts help cut through turbulence can go lighter slower yet Obviously believe being able fly slowly secret ultimate pattern ap pears retracts will make slow flying practical under wide range conditions Impact Stunt going take couple years us rethink stunt de sign use retracts full advantage meantime lot will depend Nationals year next will also accelerate dominance retracts big-time flier converts use soon know def initely although system Initially will see few retract really getting clever think am dealing facts theory although observations based flying impressions alone may 100 percent accurate can think no category indoor microfilm rubber-powered RC pattern has experienced improvement due increased aerodynamic efficiency effects retracted gear stunt model subtleno big thing happens total little improvements better-flying aircraft better pat tern no stretch imagination does retracted gear make aircraft fly worse well-known flier has suggested 1 Penetration wind low speed seems better overhead eights 2 Wobble tip roll hinging Dutch roll lateral oscillation choose term seem reduced 3 Corner exits cleaner less ships fly better best rigid gear ones will take can re member long took auto-stab auto-rudder set-ups dominate FAI free flight several years possible win non-automated flying surfaces because sheer weight numbers fre quent malfunctioning failure prop erly utilize automation producing com pletely new designs rather applying new devices existing designs Now top fliers use auto-surfaces same process occurred RC pattern rat racing hand-launched glider events have experienced dramatic transitions caused single technological innovation going take least contest Continued page 100 August1978 49 Prototype system used smaller Seelig Mini-Combo timer used Nordic gliders Crude trip wires necessary because timer Stripped down Nordic line shown lock system down prior takeoff other release main tension anrina axtnninn Combination springs main spring between Nyrods supplies power retraction smaller spring returns system extension made once tension big spring released timer Picture suggests system light weight should reliable Specifically designed retracts authors new Chizier weighs 39 ounces complete Timer installa tion nose rubber mounted cushion against vibration Grumman Guardian Class Carrier XTB3F28/T\CLD-102 IBy IgCatalog25cRag Edwards IMODERNISTIC MODELSj PO BOX 6974 ALBUQ NM 87197 derwritten TRW Thompson Trophy Check out Dennis Norman 13885 Edgewater Dr Lakewood OH 44107 club Flying Aces oriented plans alone worth several times ante neat source recent issue con cerns 45 b/w 8 x 10 prints available US Government Printing Office Washington DC $435 Pioneer USAF types jet-age subjects Besides helpful hints tips 3-view drawings plans included super Book Buy Month Anyone really serious about FF Scale can no better check William McCombs book Flying Improving Scale Model Airplanes Some us learn hard way through thousands trial-and-error flights Some better suited applying well-presented theoretical approaches latter persuasion $695 plus $145 parcel post will bring information will probably ever need Send MAN North Broad way White Plains NY 10601 Maybe club would like give copy worst crash next meet FAC Nats contest year interested FF scale almost Nine scale events over weekend July 15 16 will draw top scalers East Coast site Johnsville NAS Philadelphia spirit Flying Aces party Saturday evening promises unite kindred souls far wide See Proxies OK have some mind will agree fly $300 advance registration Lin Riechel 3301 Cindy Lane Erie PA 16506 Bill Warner 423-C San Vicente Blvd Santa Monica CA 90402 Retracts/Mathis continued page 49 season perfect new routines needed preparing model between flights Add winding timer setting little trigger mechanisms re fueling routine tense tired opens door foul-ups Another thing added psychological stress flying important pattern know ing years work can ruined gear doesnt come down nice thing about single part made unobtanium everyone can use retracts want just buy parts put Ideas Further Development other timers retractable gear set-ups available applications other contest stunt system situations utmost durability reliability crucial Tatone dether malizer timer will cheaper lighter easier install Tatone fuel shut-off timer will run long enough about 30 seconds pneumatic timers such Austincrafts accurate over pe riod long stunt pattern might used trigger retract cycle con junction some other device lower gear such pressure valve off muffler pure thrill seeing gear something sometimes before land simple dethermalizer fuse could used cant say what other brands landing gears will work although types compact light enough biggest hassle have concerns install ing gear way retracts flush airfoil bottom yet still have enough forward angle give proper wheel location stunters wing bottom highly cambered leading edge opposed RCs conventional two-wheel wing-mounted gear will re quire lot meticulous fitting give clean exterior surface solution use tricycle gear two wing gears can mounted section airfoil aft high point critical airflow pattern features find exciting about retracts realism would very easy rig simple gear attached fuselage swiveled back flush against wing would efficient attractive original idea 1967 have two sets land ing gearsone went up came down because couldnt figure out lock first gear came back down system would illegal under present rules state plane must land takeoff gear primary motives de veloping retracts provide taller landing gears prop clearance would allow use large diameter props destroying sleek ap product review product review product review pearance design still believe props ultimate key further progress stunt ability use larger props alone would justify use retracts Elias Airsport/M ever continued page 51 Add 1/16 aluminum tubes wheel bear ings Make cabane struts 1/64 ply wood install fuselage Tail Surfaces Make cardboard patterns outline stabilizer fin rudder Soak strips 1/32 sq hard balsa bass wood boiling waterform around cardboard pattern pins Let dry thor oughly pin over drawings stall 1/20 balsa spars ribs little trick learned keep tail surfaces warping Make frame out 1 X 2 lumber big enough glue about quarter sheet Japanese tissue water doped dry give coat thinned nitrate dope 50/50 dope thinner dry remove form cover fin rudder Put AIRSPORT sign side fuselage taping piece colored Japanese tissue over plans painting sign white nitrate dope Make two signs side fuselage Carefully position paper AIRSPORT sign over fuselage proper place glue framework dope Glue another piece white Japanese tissue frame water dope give coat nitrate dope Mix Floquil silver railroad paint nitrate dope pour off thinner top Floquil paint use thick aluminum bottom bot tle Spray lightly white paper airbrushjust enough give silver color Now cover horizontal stabilizer elevators doped paper Wings Make cardboard templates wing tip trailing edge wing Soak strips 1/32 hard balsa basswood hot water form around trailing edge wing tip patterns same did around tail surfaces Make up sliced ribs using metal template top bottom ribs Pin wing tip trailing edge leading edge plans install top section sliced ribs Remove wings plans install bottom ribs Notch leading edge trailing edge crack form correct dihedral angle Make 1/32 balsa spars stick correct positions gluing Titebond glue Make up spar splices 1/32 balsa glue spars correct dihedral angle Glue fillers between ribs wing strut center-section strut locations gave wings about 1/16 washout trailing edge 1/16 higher leading edge Cover lightweight white Japanese tissue water dope give coat thinned-out nitrate dope Spray wings silverthe same used 100 ModelAviation product review product review product review Seen Toledo li-lb McDonnellDoug las F-15 Duane Johnson will longawaited kit World Engines two duct ed fan 40s Ship can fly engine World Engines 8960 Rossash Ave Cincinnati ON 45236
Edition: Model Aviation - 1978/08
Page Numbers: 46, 47, 48, 49, 100
This reliable system offers advantages merit individual experimentation U Dick Mathis LANDING GEARS have posed problems aircraft designers beginning Wright brothers solved problem leaving landing gear ground Subsequent designers have yet escape fact airplanes useful have drag around 100 percent time something use 5 percent time Since landing gears interface ground rather air shape requirements have always decidedly unaerodynamic may account revulsion designers feel process building aircraft em phasizes dilemma example breezing along Hot Stuffing beautiful light balsa spruce pieces other suddenly come realm music wire nuts bolts solder plywood etc have use different glue tools attach some heavy ungainly landing gear sleek device Full-scale manufacturers have same problem Most use landing gear assemblies fabricated other com panies have special tools tech nology required model airplane manufacturers suffer example five years before company acquired machinery knowledge necessary properly manufacture kit designs landing gears Until simply manu factured designs regard suspicion anyone professes really like landing gears Besides inherently repulsive phys ical attributes landing gears sorts bad things air flow slow aircraft down foul up orderly flow air around wing fuselage 46 Model Aviation novelty wave future Retracted view shows close me gear set t reauce moments inertia wing Adjusto-Jig gear has provision adjustment travel wheel well Gear fairings shown aluminum templates laminated basswood fairings made 4This prototype system installed old ship day no attempt seal off wing air flow oil Tests taped-over openings indicated no per formance differentialbut thats gospel siphon off precious power lowest speeds essence landing gears irritate air air responds making aircraft fly worse Finally would unrealistic especially since discussing modeling event CL Stunt top fliers design latest winners around paint scheme going use failed men tion landing gears look bad Retracts two good things 1 make aircraft efficient aerody namically 2 better aesthet ically other hand three bad things 1 make construction difficult 2 heavier 3 less reliable Therefore fans playing percentages will see no need mess up good safe thing will read no further Gamblers others like see things happen will stay After studying situation since 1967 building nothing finally got work retracts stunt wintertesting redesigningand have concluded work worth effort Pri marily will describe prototype sys tem flying conventional ship designed originally fixed gears second system new un tested aircraft designed specifically retracts 78 contest season will fully described after proves itself Next will describe what effects re tracts have finally discuss pros cons retracts try predict role future stunt System should state first second third re tract system stunt Nevertheless probably first competitive system objective developing retracts have retracts own sake rather beat people big contests would enjoy having fun watching gear go up down will simple install system profile kit design system blends V2A RC components clockwork timer used free fighters com ponents obtainable commercially system costs $25 Seelig timer $13 Adjusto-Jig retracting gear few dollars other devises pushrods springs junk described shortly total costs less finish new ship big thing makes retracts pos sible us sleep milling machine foot bed long-awaited introduction re tracts RC namely Adjusto-Jig brand beefier others appeared about same time stunter needs I/s music wire gears handle smoothlysmaller ones vibrate landPROTOTYPE GEAR RETRACTION SYSTEM Rear aircraft Larger spring least ten times powerful return spring Size springs depends weight wheels drag system line#l 1 Top View Outward push retracts gear inward pull lowers Small Veco bellcrank Adjusto-jig l/2A retracts Try keep wheels light practical ditto fairings retract spring will have too powerful I Timerreleasesne #1 after 15 - seconds retract gearre leases line #2 about 360 se conds lower gear lines Sullivan CO braided steel line #2 i Larger spring provides retrac tion force pulling aft bellcrank takeoff position line #1 overrides sprinq lock ing wheels down position timer releases line #2 tension larger spring lost Once both lines release weak small spring returns system its starting position allowing wheels come down gravity 1/16 MW pushrod 60 Bend short leg bellcrank down let spring cables clear pushrods End small spring attaches airframe Fulcrum reverses pull direction line #1 comes gear kit August1978 47 Construction Chizler gear bay blocks off openings aerodynamic cleanliness stop oil seepage Adiusto-Jig gear relies gravity extend end flight lock automatically Unit weight 1-5/8 oz. including wire some would needed anyway ingand Adjusto-Jig gear has /s wire doubt however whether smoothly flown stunter needs much strength gear mount area RC Adjusto-Jig gear mechanism adequate new gear systems fer nose gears too Seelig timer used made Ger famous free fighter same name precision clockwork affair thoroughly overengineered lots bearing surfaces other good things make timers reliable universal timer used FAI free-flight people over world rarely fails although can readily set incorrectly cause interesting things happen since capable doing four things once Free fighters use four functions like 1 67 seconds shut off engine 2 69 seconds actuate rudder 3 71 seconds actuate elevator glide 4 185 seconds dethermalize functions can set occur time over period min utes necessary use functions mechanism makes model roll takeoff timer initiates retract cycle after about 15 seconds 2 laps gears go up instantly noiselessly have never detected trim change occurs may matter instant correction being made pilot unconsciouslythe same gusts turbulence pattern completed gear retracted timer releases retract spring within about 20 seconds other 20 seconds engine run left gear comes down motor quits fuel exhaustion plane lands will have already noticed possibility shutting engine off timer will especially nice flying under ridiculous FAI time limit slow pattern leaves very little time avoid overrun Effects There superstition ignorance about stunt design other event theories am hearing explain retracts wont help things happen revolving drum spiral groove cut its side wire hook fits groove works its way top spiral groove rotates wire eventually escapes drum releases whatever lines have connected sort mousetrap set-up Short duration functions can done three-notched discs revolve axle separate drum impos sible explain timer unless can see work Seelig Type FiG may ob tained $2500 Doug Galbreath 707 Second St Davis CA 95616 Watch top FAI man work day will have no reservations about whether Seelig timer will stand up stunt aircraft ships launcher stooge actuates timer lets 48 Model Aviation Heart system Seelig FF timer Spiral-grooved disk runs over 6 mm desired three flat disks notches provide short duration functions less 30 sec Button-like plunger held down wire clip on-off switch Weight 1-3/8 oz length 2-1/2 nIzer ~ ... h~ ...dnism may replaced Rectangular areas covered screw-mounted 005 aluminum sheet Springs actuation lines located aft section fuselage Actuation lines taped painting Cosmetic advantages ot retracts obvious opportunities tor aesigners oeveiop new styles aircraft designs Tail wheel could retracted Small wing skids mounted wing tips cowl bottom would protect ship abrasion should malfunction occur dramatic deceleration 4 Level flight smoother less tendency hunt up down 5 Gusts traversed easily 6 There no increased tendency wind-up gain speed wind doing consecutive loops earthshaking con sider what better penetration means someone like loves slow patterns flown light airplanes relatively little power Remember turbulence always killed light slow ones retracts help cut through turbulence can go lighter slower yet Obviously believe being able fly slowly secret ultimate pattern ap pears retracts will make slow flying practical under wide range conditions Impact Stunt going take couple years us rethink stunt de sign use retracts full advantage meantime lot will depend Nationals year next will also accelerate dominance retracts big-time flier converts use soon know def initely although system Initially will see few retract really getting clever think am dealing facts theory although observations based flying impressions alone may 100 percent accurate can think no category indoor microfilm rubber-powered RC pattern has experienced improvement due increased aerodynamic efficiency effects retracted gear stunt model subtleno big thing happens total little improvements better-flying aircraft better pat tern no stretch imagination does retracted gear make aircraft fly worse well-known flier has suggested 1 Penetration wind low speed seems better overhead eights 2 Wobble tip roll hinging Dutch roll lateral oscillation choose term seem reduced 3 Corner exits cleaner less ships fly better best rigid gear ones will take can re member long took auto-stab auto-rudder set-ups dominate FAI free flight several years possible win non-automated flying surfaces because sheer weight numbers fre quent malfunctioning failure prop erly utilize automation producing com pletely new designs rather applying new devices existing designs Now top fliers use auto-surfaces same process occurred RC pattern rat racing hand-launched glider events have experienced dramatic transitions caused single technological innovation going take least contest Continued page 100 August1978 49 Prototype system used smaller Seelig Mini-Combo timer used Nordic gliders Crude trip wires necessary because timer Stripped down Nordic line shown lock system down prior takeoff other release main tension anrina axtnninn Combination springs main spring between Nyrods supplies power retraction smaller spring returns system extension made once tension big spring released timer Picture suggests system light weight should reliable Specifically designed retracts authors new Chizier weighs 39 ounces complete Timer installa tion nose rubber mounted cushion against vibration Grumman Guardian Class Carrier XTB3F28/T\CLD-102 IBy IgCatalog25cRag Edwards IMODERNISTIC MODELSj PO BOX 6974 ALBUQ NM 87197 derwritten TRW Thompson Trophy Check out Dennis Norman 13885 Edgewater Dr Lakewood OH 44107 club Flying Aces oriented plans alone worth several times ante neat source recent issue con cerns 45 b/w 8 x 10 prints available US Government Printing Office Washington DC $435 Pioneer USAF types jet-age subjects Besides helpful hints tips 3-view drawings plans included super Book Buy Month Anyone really serious about FF Scale can no better check William McCombs book Flying Improving Scale Model Airplanes Some us learn hard way through thousands trial-and-error flights Some better suited applying well-presented theoretical approaches latter persuasion $695 plus $145 parcel post will bring information will probably ever need Send MAN North Broad way White Plains NY 10601 Maybe club would like give copy worst crash next meet FAC Nats contest year interested FF scale almost Nine scale events over weekend July 15 16 will draw top scalers East Coast site Johnsville NAS Philadelphia spirit Flying Aces party Saturday evening promises unite kindred souls far wide See Proxies OK have some mind will agree fly $300 advance registration Lin Riechel 3301 Cindy Lane Erie PA 16506 Bill Warner 423-C San Vicente Blvd Santa Monica CA 90402 Retracts/Mathis continued page 49 season perfect new routines needed preparing model between flights Add winding timer setting little trigger mechanisms re fueling routine tense tired opens door foul-ups Another thing added psychological stress flying important pattern know ing years work can ruined gear doesnt come down nice thing about single part made unobtanium everyone can use retracts want just buy parts put Ideas Further Development other timers retractable gear set-ups available applications other contest stunt system situations utmost durability reliability crucial Tatone dether malizer timer will cheaper lighter easier install Tatone fuel shut-off timer will run long enough about 30 seconds pneumatic timers such Austincrafts accurate over pe riod long stunt pattern might used trigger retract cycle con junction some other device lower gear such pressure valve off muffler pure thrill seeing gear something sometimes before land simple dethermalizer fuse could used cant say what other brands landing gears will work although types compact light enough biggest hassle have concerns install ing gear way retracts flush airfoil bottom yet still have enough forward angle give proper wheel location stunters wing bottom highly cambered leading edge opposed RCs conventional two-wheel wing-mounted gear will re quire lot meticulous fitting give clean exterior surface solution use tricycle gear two wing gears can mounted section airfoil aft high point critical airflow pattern features find exciting about retracts realism would very easy rig simple gear attached fuselage swiveled back flush against wing would efficient attractive original idea 1967 have two sets land ing gearsone went up came down because couldnt figure out lock first gear came back down system would illegal under present rules state plane must land takeoff gear primary motives de veloping retracts provide taller landing gears prop clearance would allow use large diameter props destroying sleek ap product review product review product review pearance design still believe props ultimate key further progress stunt ability use larger props alone would justify use retracts Elias Airsport/M ever continued page 51 Add 1/16 aluminum tubes wheel bear ings Make cabane struts 1/64 ply wood install fuselage Tail Surfaces Make cardboard patterns outline stabilizer fin rudder Soak strips 1/32 sq hard balsa bass wood boiling waterform around cardboard pattern pins Let dry thor oughly pin over drawings stall 1/20 balsa spars ribs little trick learned keep tail surfaces warping Make frame out 1 X 2 lumber big enough glue about quarter sheet Japanese tissue water doped dry give coat thinned nitrate dope 50/50 dope thinner dry remove form cover fin rudder Put AIRSPORT sign side fuselage taping piece colored Japanese tissue over plans painting sign white nitrate dope Make two signs side fuselage Carefully position paper AIRSPORT sign over fuselage proper place glue framework dope Glue another piece white Japanese tissue frame water dope give coat nitrate dope Mix Floquil silver railroad paint nitrate dope pour off thinner top Floquil paint use thick aluminum bottom bot tle Spray lightly white paper airbrushjust enough give silver color Now cover horizontal stabilizer elevators doped paper Wings Make cardboard templates wing tip trailing edge wing Soak strips 1/32 hard balsa basswood hot water form around trailing edge wing tip patterns same did around tail surfaces Make up sliced ribs using metal template top bottom ribs Pin wing tip trailing edge leading edge plans install top section sliced ribs Remove wings plans install bottom ribs Notch leading edge trailing edge crack form correct dihedral angle Make 1/32 balsa spars stick correct positions gluing Titebond glue Make up spar splices 1/32 balsa glue spars correct dihedral angle Glue fillers between ribs wing strut center-section strut locations gave wings about 1/16 washout trailing edge 1/16 higher leading edge Cover lightweight white Japanese tissue water dope give coat thinned-out nitrate dope Spray wings silverthe same used 100 ModelAviation product review product review product review Seen Toledo li-lb McDonnellDoug las F-15 Duane Johnson will longawaited kit World Engines two duct ed fan 40s Ship can fly engine World Engines 8960 Rossash Ave Cincinnati ON 45236
Edition: Model Aviation - 1978/08
Page Numbers: 46, 47, 48, 49, 100
This reliable system offers advantages merit individual experimentation U Dick Mathis LANDING GEARS have posed problems aircraft designers beginning Wright brothers solved problem leaving landing gear ground Subsequent designers have yet escape fact airplanes useful have drag around 100 percent time something use 5 percent time Since landing gears interface ground rather air shape requirements have always decidedly unaerodynamic may account revulsion designers feel process building aircraft em phasizes dilemma example breezing along Hot Stuffing beautiful light balsa spruce pieces other suddenly come realm music wire nuts bolts solder plywood etc have use different glue tools attach some heavy ungainly landing gear sleek device Full-scale manufacturers have same problem Most use landing gear assemblies fabricated other com panies have special tools tech nology required model airplane manufacturers suffer example five years before company acquired machinery knowledge necessary properly manufacture kit designs landing gears Until simply manu factured designs regard suspicion anyone professes really like landing gears Besides inherently repulsive phys ical attributes landing gears sorts bad things air flow slow aircraft down foul up orderly flow air around wing fuselage 46 Model Aviation novelty wave future Retracted view shows close me gear set t reauce moments inertia wing Adjusto-Jig gear has provision adjustment travel wheel well Gear fairings shown aluminum templates laminated basswood fairings made 4This prototype system installed old ship day no attempt seal off wing air flow oil Tests taped-over openings indicated no per formance differentialbut thats gospel siphon off precious power lowest speeds essence landing gears irritate air air responds making aircraft fly worse Finally would unrealistic especially since discussing modeling event CL Stunt top fliers design latest winners around paint scheme going use failed men tion landing gears look bad Retracts two good things 1 make aircraft efficient aerody namically 2 better aesthet ically other hand three bad things 1 make construction difficult 2 heavier 3 less reliable Therefore fans playing percentages will see no need mess up good safe thing will read no further Gamblers others like see things happen will stay After studying situation since 1967 building nothing finally got work retracts stunt wintertesting redesigningand have concluded work worth effort Pri marily will describe prototype sys tem flying conventional ship designed originally fixed gears second system new un tested aircraft designed specifically retracts 78 contest season will fully described after proves itself Next will describe what effects re tracts have finally discuss pros cons retracts try predict role future stunt System should state first second third re tract system stunt Nevertheless probably first competitive system objective developing retracts have retracts own sake rather beat people big contests would enjoy having fun watching gear go up down will simple install system profile kit design system blends V2A RC components clockwork timer used free fighters com ponents obtainable commercially system costs $25 Seelig timer $13 Adjusto-Jig retracting gear few dollars other devises pushrods springs junk described shortly total costs less finish new ship big thing makes retracts pos sible us sleep milling machine foot bed long-awaited introduction re tracts RC namely Adjusto-Jig brand beefier others appeared about same time stunter needs I/s music wire gears handle smoothlysmaller ones vibrate landPROTOTYPE GEAR RETRACTION SYSTEM Rear aircraft Larger spring least ten times powerful return spring Size springs depends weight wheels drag system line#l 1 Top View Outward push retracts gear inward pull lowers Small Veco bellcrank Adjusto-jig l/2A retracts Try keep wheels light practical ditto fairings retract spring will have too powerful I Timerreleasesne #1 after 15 - seconds retract gearre leases line #2 about 360 se conds lower gear lines Sullivan CO braided steel line #2 i Larger spring provides retrac tion force pulling aft bellcrank takeoff position line #1 overrides sprinq lock ing wheels down position timer releases line #2 tension larger spring lost Once both lines release weak small spring returns system its starting position allowing wheels come down gravity 1/16 MW pushrod 60 Bend short leg bellcrank down let spring cables clear pushrods End small spring attaches airframe Fulcrum reverses pull direction line #1 comes gear kit August1978 47 Construction Chizler gear bay blocks off openings aerodynamic cleanliness stop oil seepage Adiusto-Jig gear relies gravity extend end flight lock automatically Unit weight 1-5/8 oz. including wire some would needed anyway ingand Adjusto-Jig gear has /s wire doubt however whether smoothly flown stunter needs much strength gear mount area RC Adjusto-Jig gear mechanism adequate new gear systems fer nose gears too Seelig timer used made Ger famous free fighter same name precision clockwork affair thoroughly overengineered lots bearing surfaces other good things make timers reliable universal timer used FAI free-flight people over world rarely fails although can readily set incorrectly cause interesting things happen since capable doing four things once Free fighters use four functions like 1 67 seconds shut off engine 2 69 seconds actuate rudder 3 71 seconds actuate elevator glide 4 185 seconds dethermalize functions can set occur time over period min utes necessary use functions mechanism makes model roll takeoff timer initiates retract cycle after about 15 seconds 2 laps gears go up instantly noiselessly have never detected trim change occurs may matter instant correction being made pilot unconsciouslythe same gusts turbulence pattern completed gear retracted timer releases retract spring within about 20 seconds other 20 seconds engine run left gear comes down motor quits fuel exhaustion plane lands will have already noticed possibility shutting engine off timer will especially nice flying under ridiculous FAI time limit slow pattern leaves very little time avoid overrun Effects There superstition ignorance about stunt design other event theories am hearing explain retracts wont help things happen revolving drum spiral groove cut its side wire hook fits groove works its way top spiral groove rotates wire eventually escapes drum releases whatever lines have connected sort mousetrap set-up Short duration functions can done three-notched discs revolve axle separate drum impos sible explain timer unless can see work Seelig Type FiG may ob tained $2500 Doug Galbreath 707 Second St Davis CA 95616 Watch top FAI man work day will have no reservations about whether Seelig timer will stand up stunt aircraft ships launcher stooge actuates timer lets 48 Model Aviation Heart system Seelig FF timer Spiral-grooved disk runs over 6 mm desired three flat disks notches provide short duration functions less 30 sec Button-like plunger held down wire clip on-off switch Weight 1-3/8 oz length 2-1/2 nIzer ~ ... h~ ...dnism may replaced Rectangular areas covered screw-mounted 005 aluminum sheet Springs actuation lines located aft section fuselage Actuation lines taped painting Cosmetic advantages ot retracts obvious opportunities tor aesigners oeveiop new styles aircraft designs Tail wheel could retracted Small wing skids mounted wing tips cowl bottom would protect ship abrasion should malfunction occur dramatic deceleration 4 Level flight smoother less tendency hunt up down 5 Gusts traversed easily 6 There no increased tendency wind-up gain speed wind doing consecutive loops earthshaking con sider what better penetration means someone like loves slow patterns flown light airplanes relatively little power Remember turbulence always killed light slow ones retracts help cut through turbulence can go lighter slower yet Obviously believe being able fly slowly secret ultimate pattern ap pears retracts will make slow flying practical under wide range conditions Impact Stunt going take couple years us rethink stunt de sign use retracts full advantage meantime lot will depend Nationals year next will also accelerate dominance retracts big-time flier converts use soon know def initely although system Initially will see few retract really getting clever think am dealing facts theory although observations based flying impressions alone may 100 percent accurate can think no category indoor microfilm rubber-powered RC pattern has experienced improvement due increased aerodynamic efficiency effects retracted gear stunt model subtleno big thing happens total little improvements better-flying aircraft better pat tern no stretch imagination does retracted gear make aircraft fly worse well-known flier has suggested 1 Penetration wind low speed seems better overhead eights 2 Wobble tip roll hinging Dutch roll lateral oscillation choose term seem reduced 3 Corner exits cleaner less ships fly better best rigid gear ones will take can re member long took auto-stab auto-rudder set-ups dominate FAI free flight several years possible win non-automated flying surfaces because sheer weight numbers fre quent malfunctioning failure prop erly utilize automation producing com pletely new designs rather applying new devices existing designs Now top fliers use auto-surfaces same process occurred RC pattern rat racing hand-launched glider events have experienced dramatic transitions caused single technological innovation going take least contest Continued page 100 August1978 49 Prototype system used smaller Seelig Mini-Combo timer used Nordic gliders Crude trip wires necessary because timer Stripped down Nordic line shown lock system down prior takeoff other release main tension anrina axtnninn Combination springs main spring between Nyrods supplies power retraction smaller spring returns system extension made once tension big spring released timer Picture suggests system light weight should reliable Specifically designed retracts authors new Chizier weighs 39 ounces complete Timer installa tion nose rubber mounted cushion against vibration Grumman Guardian Class Carrier XTB3F28/T\CLD-102 IBy IgCatalog25cRag Edwards IMODERNISTIC MODELSj PO BOX 6974 ALBUQ NM 87197 derwritten TRW Thompson Trophy Check out Dennis Norman 13885 Edgewater Dr Lakewood OH 44107 club Flying Aces oriented plans alone worth several times ante neat source recent issue con cerns 45 b/w 8 x 10 prints available US Government Printing Office Washington DC $435 Pioneer USAF types jet-age subjects Besides helpful hints tips 3-view drawings plans included super Book Buy Month Anyone really serious about FF Scale can no better check William McCombs book Flying Improving Scale Model Airplanes Some us learn hard way through thousands trial-and-error flights Some better suited applying well-presented theoretical approaches latter persuasion $695 plus $145 parcel post will bring information will probably ever need Send MAN North Broad way White Plains NY 10601 Maybe club would like give copy worst crash next meet FAC Nats contest year interested FF scale almost Nine scale events over weekend July 15 16 will draw top scalers East Coast site Johnsville NAS Philadelphia spirit Flying Aces party Saturday evening promises unite kindred souls far wide See Proxies OK have some mind will agree fly $300 advance registration Lin Riechel 3301 Cindy Lane Erie PA 16506 Bill Warner 423-C San Vicente Blvd Santa Monica CA 90402 Retracts/Mathis continued page 49 season perfect new routines needed preparing model between flights Add winding timer setting little trigger mechanisms re fueling routine tense tired opens door foul-ups Another thing added psychological stress flying important pattern know ing years work can ruined gear doesnt come down nice thing about single part made unobtanium everyone can use retracts want just buy parts put Ideas Further Development other timers retractable gear set-ups available applications other contest stunt system situations utmost durability reliability crucial Tatone dether malizer timer will cheaper lighter easier install Tatone fuel shut-off timer will run long enough about 30 seconds pneumatic timers such Austincrafts accurate over pe riod long stunt pattern might used trigger retract cycle con junction some other device lower gear such pressure valve off muffler pure thrill seeing gear something sometimes before land simple dethermalizer fuse could used cant say what other brands landing gears will work although types compact light enough biggest hassle have concerns install ing gear way retracts flush airfoil bottom yet still have enough forward angle give proper wheel location stunters wing bottom highly cambered leading edge opposed RCs conventional two-wheel wing-mounted gear will re quire lot meticulous fitting give clean exterior surface solution use tricycle gear two wing gears can mounted section airfoil aft high point critical airflow pattern features find exciting about retracts realism would very easy rig simple gear attached fuselage swiveled back flush against wing would efficient attractive original idea 1967 have two sets land ing gearsone went up came down because couldnt figure out lock first gear came back down system would illegal under present rules state plane must land takeoff gear primary motives de veloping retracts provide taller landing gears prop clearance would allow use large diameter props destroying sleek ap product review product review product review pearance design still believe props ultimate key further progress stunt ability use larger props alone would justify use retracts Elias Airsport/M ever continued page 51 Add 1/16 aluminum tubes wheel bear ings Make cabane struts 1/64 ply wood install fuselage Tail Surfaces Make cardboard patterns outline stabilizer fin rudder Soak strips 1/32 sq hard balsa bass wood boiling waterform around cardboard pattern pins Let dry thor oughly pin over drawings stall 1/20 balsa spars ribs little trick learned keep tail surfaces warping Make frame out 1 X 2 lumber big enough glue about quarter sheet Japanese tissue water doped dry give coat thinned nitrate dope 50/50 dope thinner dry remove form cover fin rudder Put AIRSPORT sign side fuselage taping piece colored Japanese tissue over plans painting sign white nitrate dope Make two signs side fuselage Carefully position paper AIRSPORT sign over fuselage proper place glue framework dope Glue another piece white Japanese tissue frame water dope give coat nitrate dope Mix Floquil silver railroad paint nitrate dope pour off thinner top Floquil paint use thick aluminum bottom bot tle Spray lightly white paper airbrushjust enough give silver color Now cover horizontal stabilizer elevators doped paper Wings Make cardboard templates wing tip trailing edge wing Soak strips 1/32 hard balsa basswood hot water form around trailing edge wing tip patterns same did around tail surfaces Make up sliced ribs using metal template top bottom ribs Pin wing tip trailing edge leading edge plans install top section sliced ribs Remove wings plans install bottom ribs Notch leading edge trailing edge crack form correct dihedral angle Make 1/32 balsa spars stick correct positions gluing Titebond glue Make up spar splices 1/32 balsa glue spars correct dihedral angle Glue fillers between ribs wing strut center-section strut locations gave wings about 1/16 washout trailing edge 1/16 higher leading edge Cover lightweight white Japanese tissue water dope give coat thinned-out nitrate dope Spray wings silverthe same used 100 ModelAviation product review product review product review Seen Toledo li-lb McDonnellDoug las F-15 Duane Johnson will longawaited kit World Engines two duct ed fan 40s Ship can fly engine World Engines 8960 Rossash Ave Cincinnati ON 45236
Edition: Model Aviation - 1978/08
Page Numbers: 46, 47, 48, 49, 100
This reliable system offers advantages merit individual experimentation U Dick Mathis LANDING GEARS have posed problems aircraft designers beginning Wright brothers solved problem leaving landing gear ground Subsequent designers have yet escape fact airplanes useful have drag around 100 percent time something use 5 percent time Since landing gears interface ground rather air shape requirements have always decidedly unaerodynamic may account revulsion designers feel process building aircraft em phasizes dilemma example breezing along Hot Stuffing beautiful light balsa spruce pieces other suddenly come realm music wire nuts bolts solder plywood etc have use different glue tools attach some heavy ungainly landing gear sleek device Full-scale manufacturers have same problem Most use landing gear assemblies fabricated other com panies have special tools tech nology required model airplane manufacturers suffer example five years before company acquired machinery knowledge necessary properly manufacture kit designs landing gears Until simply manu factured designs regard suspicion anyone professes really like landing gears Besides inherently repulsive phys ical attributes landing gears sorts bad things air flow slow aircraft down foul up orderly flow air around wing fuselage 46 Model Aviation novelty wave future Retracted view shows close me gear set t reauce moments inertia wing Adjusto-Jig gear has provision adjustment travel wheel well Gear fairings shown aluminum templates laminated basswood fairings made 4This prototype system installed old ship day no attempt seal off wing air flow oil Tests taped-over openings indicated no per formance differentialbut thats gospel siphon off precious power lowest speeds essence landing gears irritate air air responds making aircraft fly worse Finally would unrealistic especially since discussing modeling event CL Stunt top fliers design latest winners around paint scheme going use failed men tion landing gears look bad Retracts two good things 1 make aircraft efficient aerody namically 2 better aesthet ically other hand three bad things 1 make construction difficult 2 heavier 3 less reliable Therefore fans playing percentages will see no need mess up good safe thing will read no further Gamblers others like see things happen will stay After studying situation since 1967 building nothing finally got work retracts stunt wintertesting redesigningand have concluded work worth effort Pri marily will describe prototype sys tem flying conventional ship designed originally fixed gears second system new un tested aircraft designed specifically retracts 78 contest season will fully described after proves itself Next will describe what effects re tracts have finally discuss pros cons retracts try predict role future stunt System should state first second third re tract system stunt Nevertheless probably first competitive system objective developing retracts have retracts own sake rather beat people big contests would enjoy having fun watching gear go up down will simple install system profile kit design system blends V2A RC components clockwork timer used free fighters com ponents obtainable commercially system costs $25 Seelig timer $13 Adjusto-Jig retracting gear few dollars other devises pushrods springs junk described shortly total costs less finish new ship big thing makes retracts pos sible us sleep milling machine foot bed long-awaited introduction re tracts RC namely Adjusto-Jig brand beefier others appeared about same time stunter needs I/s music wire gears handle smoothlysmaller ones vibrate landPROTOTYPE GEAR RETRACTION SYSTEM Rear aircraft Larger spring least ten times powerful return spring Size springs depends weight wheels drag system line#l 1 Top View Outward push retracts gear inward pull lowers Small Veco bellcrank Adjusto-jig l/2A retracts Try keep wheels light practical ditto fairings retract spring will have too powerful I Timerreleasesne #1 after 15 - seconds retract gearre leases line #2 about 360 se conds lower gear lines Sullivan CO braided steel line #2 i Larger spring provides retrac tion force pulling aft bellcrank takeoff position line #1 overrides sprinq lock ing wheels down position timer releases line #2 tension larger spring lost Once both lines release weak small spring returns system its starting position allowing wheels come down gravity 1/16 MW pushrod 60 Bend short leg bellcrank down let spring cables clear pushrods End small spring attaches airframe Fulcrum reverses pull direction line #1 comes gear kit August1978 47 Construction Chizler gear bay blocks off openings aerodynamic cleanliness stop oil seepage Adiusto-Jig gear relies gravity extend end flight lock automatically Unit weight 1-5/8 oz. including wire some would needed anyway ingand Adjusto-Jig gear has /s wire doubt however whether smoothly flown stunter needs much strength gear mount area RC Adjusto-Jig gear mechanism adequate new gear systems fer nose gears too Seelig timer used made Ger famous free fighter same name precision clockwork affair thoroughly overengineered lots bearing surfaces other good things make timers reliable universal timer used FAI free-flight people over world rarely fails although can readily set incorrectly cause interesting things happen since capable doing four things once Free fighters use four functions like 1 67 seconds shut off engine 2 69 seconds actuate rudder 3 71 seconds actuate elevator glide 4 185 seconds dethermalize functions can set occur time over period min utes necessary use functions mechanism makes model roll takeoff timer initiates retract cycle after about 15 seconds 2 laps gears go up instantly noiselessly have never detected trim change occurs may matter instant correction being made pilot unconsciouslythe same gusts turbulence pattern completed gear retracted timer releases retract spring within about 20 seconds other 20 seconds engine run left gear comes down motor quits fuel exhaustion plane lands will have already noticed possibility shutting engine off timer will especially nice flying under ridiculous FAI time limit slow pattern leaves very little time avoid overrun Effects There superstition ignorance about stunt design other event theories am hearing explain retracts wont help things happen revolving drum spiral groove cut its side wire hook fits groove works its way top spiral groove rotates wire eventually escapes drum releases whatever lines have connected sort mousetrap set-up Short duration functions can done three-notched discs revolve axle separate drum impos sible explain timer unless can see work Seelig Type FiG may ob tained $2500 Doug Galbreath 707 Second St Davis CA 95616 Watch top FAI man work day will have no reservations about whether Seelig timer will stand up stunt aircraft ships launcher stooge actuates timer lets 48 Model Aviation Heart system Seelig FF timer Spiral-grooved disk runs over 6 mm desired three flat disks notches provide short duration functions less 30 sec Button-like plunger held down wire clip on-off switch Weight 1-3/8 oz length 2-1/2 nIzer ~ ... h~ ...dnism may replaced Rectangular areas covered screw-mounted 005 aluminum sheet Springs actuation lines located aft section fuselage Actuation lines taped painting Cosmetic advantages ot retracts obvious opportunities tor aesigners oeveiop new styles aircraft designs Tail wheel could retracted Small wing skids mounted wing tips cowl bottom would protect ship abrasion should malfunction occur dramatic deceleration 4 Level flight smoother less tendency hunt up down 5 Gusts traversed easily 6 There no increased tendency wind-up gain speed wind doing consecutive loops earthshaking con sider what better penetration means someone like loves slow patterns flown light airplanes relatively little power Remember turbulence always killed light slow ones retracts help cut through turbulence can go lighter slower yet Obviously believe being able fly slowly secret ultimate pattern ap pears retracts will make slow flying practical under wide range conditions Impact Stunt going take couple years us rethink stunt de sign use retracts full advantage meantime lot will depend Nationals year next will also accelerate dominance retracts big-time flier converts use soon know def initely although system Initially will see few retract really getting clever think am dealing facts theory although observations based flying impressions alone may 100 percent accurate can think no category indoor microfilm rubber-powered RC pattern has experienced improvement due increased aerodynamic efficiency effects retracted gear stunt model subtleno big thing happens total little improvements better-flying aircraft better pat tern no stretch imagination does retracted gear make aircraft fly worse well-known flier has suggested 1 Penetration wind low speed seems better overhead eights 2 Wobble tip roll hinging Dutch roll lateral oscillation choose term seem reduced 3 Corner exits cleaner less ships fly better best rigid gear ones will take can re member long took auto-stab auto-rudder set-ups dominate FAI free flight several years possible win non-automated flying surfaces because sheer weight numbers fre quent malfunctioning failure prop erly utilize automation producing com pletely new designs rather applying new devices existing designs Now top fliers use auto-surfaces same process occurred RC pattern rat racing hand-launched glider events have experienced dramatic transitions caused single technological innovation going take least contest Continued page 100 August1978 49 Prototype system used smaller Seelig Mini-Combo timer used Nordic gliders Crude trip wires necessary because timer Stripped down Nordic line shown lock system down prior takeoff other release main tension anrina axtnninn Combination springs main spring between Nyrods supplies power retraction smaller spring returns system extension made once tension big spring released timer Picture suggests system light weight should reliable Specifically designed retracts authors new Chizier weighs 39 ounces complete Timer installa tion nose rubber mounted cushion against vibration Grumman Guardian Class Carrier XTB3F28/T\CLD-102 IBy IgCatalog25cRag Edwards IMODERNISTIC MODELSj PO BOX 6974 ALBUQ NM 87197 derwritten TRW Thompson Trophy Check out Dennis Norman 13885 Edgewater Dr Lakewood OH 44107 club Flying Aces oriented plans alone worth several times ante neat source recent issue con cerns 45 b/w 8 x 10 prints available US Government Printing Office Washington DC $435 Pioneer USAF types jet-age subjects Besides helpful hints tips 3-view drawings plans included super Book Buy Month Anyone really serious about FF Scale can no better check William McCombs book Flying Improving Scale Model Airplanes Some us learn hard way through thousands trial-and-error flights Some better suited applying well-presented theoretical approaches latter persuasion $695 plus $145 parcel post will bring information will probably ever need Send MAN North Broad way White Plains NY 10601 Maybe club would like give copy worst crash next meet FAC Nats contest year interested FF scale almost Nine scale events over weekend July 15 16 will draw top scalers East Coast site Johnsville NAS Philadelphia spirit Flying Aces party Saturday evening promises unite kindred souls far wide See Proxies OK have some mind will agree fly $300 advance registration Lin Riechel 3301 Cindy Lane Erie PA 16506 Bill Warner 423-C San Vicente Blvd Santa Monica CA 90402 Retracts/Mathis continued page 49 season perfect new routines needed preparing model between flights Add winding timer setting little trigger mechanisms re fueling routine tense tired opens door foul-ups Another thing added psychological stress flying important pattern know ing years work can ruined gear doesnt come down nice thing about single part made unobtanium everyone can use retracts want just buy parts put Ideas Further Development other timers retractable gear set-ups available applications other contest stunt system situations utmost durability reliability crucial Tatone dether malizer timer will cheaper lighter easier install Tatone fuel shut-off timer will run long enough about 30 seconds pneumatic timers such Austincrafts accurate over pe riod long stunt pattern might used trigger retract cycle con junction some other device lower gear such pressure valve off muffler pure thrill seeing gear something sometimes before land simple dethermalizer fuse could used cant say what other brands landing gears will work although types compact light enough biggest hassle have concerns install ing gear way retracts flush airfoil bottom yet still have enough forward angle give proper wheel location stunters wing bottom highly cambered leading edge opposed RCs conventional two-wheel wing-mounted gear will re quire lot meticulous fitting give clean exterior surface solution use tricycle gear two wing gears can mounted section airfoil aft high point critical airflow pattern features find exciting about retracts realism would very easy rig simple gear attached fuselage swiveled back flush against wing would efficient attractive original idea 1967 have two sets land ing gearsone went up came down because couldnt figure out lock first gear came back down system would illegal under present rules state plane must land takeoff gear primary motives de veloping retracts provide taller landing gears prop clearance would allow use large diameter props destroying sleek ap product review product review product review pearance design still believe props ultimate key further progress stunt ability use larger props alone would justify use retracts Elias Airsport/M ever continued page 51 Add 1/16 aluminum tubes wheel bear ings Make cabane struts 1/64 ply wood install fuselage Tail Surfaces Make cardboard patterns outline stabilizer fin rudder Soak strips 1/32 sq hard balsa bass wood boiling waterform around cardboard pattern pins Let dry thor oughly pin over drawings stall 1/20 balsa spars ribs little trick learned keep tail surfaces warping Make frame out 1 X 2 lumber big enough glue about quarter sheet Japanese tissue water doped dry give coat thinned nitrate dope 50/50 dope thinner dry remove form cover fin rudder Put AIRSPORT sign side fuselage taping piece colored Japanese tissue over plans painting sign white nitrate dope Make two signs side fuselage Carefully position paper AIRSPORT sign over fuselage proper place glue framework dope Glue another piece white Japanese tissue frame water dope give coat nitrate dope Mix Floquil silver railroad paint nitrate dope pour off thinner top Floquil paint use thick aluminum bottom bot tle Spray lightly white paper airbrushjust enough give silver color Now cover horizontal stabilizer elevators doped paper Wings Make cardboard templates wing tip trailing edge wing Soak strips 1/32 hard balsa basswood hot water form around trailing edge wing tip patterns same did around tail surfaces Make up sliced ribs using metal template top bottom ribs Pin wing tip trailing edge leading edge plans install top section sliced ribs Remove wings plans install bottom ribs Notch leading edge trailing edge crack form correct dihedral angle Make 1/32 balsa spars stick correct positions gluing Titebond glue Make up spar splices 1/32 balsa glue spars correct dihedral angle Glue fillers between ribs wing strut center-section strut locations gave wings about 1/16 washout trailing edge 1/16 higher leading edge Cover lightweight white Japanese tissue water dope give coat thinned-out nitrate dope Spray wings silverthe same used 100 ModelAviation product review product review product review Seen Toledo li-lb McDonnellDoug las F-15 Duane Johnson will longawaited kit World Engines two duct ed fan 40s Ship can fly engine World Engines 8960 Rossash Ave Cincinnati ON 45236