Adrenalin high moment launch author controls Iauncing crew unidentified Note streamer line trail ing behind plane Lets hope doesnt tangle launch crew Also note anothr airborne plane distance trailing its streamer holes fantail seen model optional method establishing te correct center-of-gravity Photo Mike Keville Super Combat Streak Bill Netzebinds Jerkline Special models flew rery well lost favor because took longer build somewhat flimsier short profile flying wing designs Mid-decade Bill Netzeband Don Still got ball rolling direction flying wings Half Fast No Body Still winning contests early Sixties Half Fast probably successful flying wing designs fos tered such clones Wow Orbit Ace Nose Cone Although largish model 465-sq-in area diffi cult build NoBody inspired spin-offs its own T-Square Omega Ban dit among An larger flying wing design 525-sq-in Reactor too expensive serious consideration average mod eler kit sold $495 time going rate Combat models $295 $395 Flying wing models turned creditable performances Combat circles Fifties consistently winning placing IN THE 35 years since its inception Combat has never quite overcome its reputa tion fad-ridden event sort eccen tric second cousin Ironically fads begun good pilots squeezing utmost out mediocre designs Expert fliers could get away features violated sound aerodynamic principlessome fact used mainly show bellwethers rankand-file Combat modelers choices quickly imitated Though fads didnt hurt models perform ance certainly didnt help much either Several less innocent features however bred spate bad designs Innovation experimentation bywords Fifties Countless designs tried modified designers freely borrowed features other air planes early part decade squarebox-fuselage planes such Hottern Zilch Expendable All-American became popular Several box-fuselage designs cropped up culminating the Nats fell out favor early Sixties due fact didnt look like then-trendy twin-boom stabilator designs because deficiencies air twin-boom stabilator owed much its popularity influence Riley Wooten big trendmakers day Riley probably could have won Nats Ringmaster Quicker spawned development Renegade Hornet short noses long box-fuselage tails Rileys design started out plankwinged Nothin As its tail design evolved became Quicker eventually VooDoo its twin tail booms stabi lator Quicker remained top-line model early Sixties Voo Doo kitted two models probably successful Combat kits ever produced As happened Rileys airfoil what think basic flaw Because lacked between-the-ribs support covering airfoil gave inconsistent performance Designed 145% thickness airfoil produced often seemed closer 10% probably averaged about 12% Despite shortcoming Rileys design very suc cessful different fliers hands Plans above-mentioned models available through author Send SASE Barry Baxter 6490 So nora Way Cypress CA 90630 com plete listing After VooDoos success designs two booms stabilator became fad hour Bill Carpenter used three booms Swoopand anything two booms suddenly passe support ing center stabilator pushrod attached thereby removing some flex control system triple boom offered obvious struc tural advantage monoboom came along triple boom turn quickly eclipsed Though offered no particular aerody namic advantage single-boom structure did shorten building time outboard booms always nuisance cover monobooms popularity has held strong since late Sixties ad vent foam Fas-Cal Combat ships have come look basically alike Though flight characteristics vary use different wing planforms airfoil sec tions casual observer differ ences hard detect spectator contest today can easily become confused whos flying what judges have fooled airplane dont know what color streamer Foam clones have taken over todays Combat cir cle Riley Wootens designs should noted worthy imitation Rileys superb flying skills however trans formed few mediocre de signs contest winners started fads some very questionable directions Rileys uninspired designs think Guided Missile Its diamond airfoil doubt worst such design ever foisted Combat commu nity Exterminator Demon Diamond just few models adopted misbegotten airfoil Incred ibly few fliers managed rack up wins ships Makes wonder what couldve done good airplane Though diamond airfoil does have advantage being easy build straight aerodynamically its disaster center pressure wing jumps high point camber leading edge back making smooth transition impossi ble Models equipped diamond airfoils sharp leading edges such Du mas Diamond particularly awkward fliers poor stalling characteris tics planes required approximately 500 circle perform loop airfoil design begins turn angle attack increases its little better flat-plate airfoil Airfoils todays designs range very good rather bad commonly used poorer designs has very blunt almost round leading edge apex about 15-20% chord mark Though airfoils will turn well theyll also slow down process have higher stall angle drag creases much higher rate fact very high drag such airfoils induce will slow plane down several miles hour level flight drag coefficient approximately 00020 blunt flat English airfoil suf fers same disadvantage con trast elliptical leading edge 30% high point has drag coefficient 000012 Since coefficient lift al identical three shapes fliers looking speed no loss maneuver ability would benefit using ellipti cal leading edge airfoil NACA 0009 0012 0015 airfoils outstanding ex amples type airfoil After experimenting different airfoil thicknesses Ive determined anything over 15% produces too much drag Al though Stunt models use thicker airfoils airplanes differ Combat models two significant respects speed wing loading Stunt models designed wing loading approximately 12 ozIsq ft stability wind performance Theyre January 1990 57 author servicing Birds Prey preparation another match air planes very easy fast build wing all-foam because its sharp taper would best left experienced foam cutters Phil Cartier Corehouse Supplies carries cores will adapt Bird Prey Any covering will work quite well Photo Russ Wilcox pair authors Birds Note double-tapered wings angled wing tips enhance aerodynamic efficiency outboard wing cut inch shorter stock Fox MK IV engine will work quite well Heavier power plants such K&B 58 Supertigre S-36 also give ex cellent performance unduly affecting center-of-gravity Photo author also engineered fly approximately 52 sec per lap contrast Combat model has wing loading about 6 oz/sq ft generally averages about 23 sec per lap 10-ft altitude thicker airfoils seen Stunt models used sake additional lift provide high drag slows airplane down desired lap time experimenting 9% airfoil Slow Combat ship based 1958 Bill Judge design called Woody sharp leading edge found 9% thickness several drawbacks- Cornering ability suffered example after changing leading edge elliptical section ran opposite problem airplane turned too well airfoil too thin maintain adequate strength particular installation couldnt keep wing together Though havent time con tinue experiments clearly much untapped potential thinner wing unusual wing tips model functional well stylish Airflow tip airfoil will move outboard across wing attempt curve around tip high pressure area under wing low pressure above tip angle keeps pressure proper side airfoil reducing tip drag increas ing lift optimum tip angle approxi mately 150 own decade weve seen Northrop Aircrafts revival its 1940s flying wing viable bombing platform As enter 1990s think time also right bringing back Combat wing vi able streamer weapon caveat As short-tailed mod els achieving proper center-of-gravity location elevator travel critical flying wings success other hand compared standard foam clone comparable size flying wing has ad vantages somewhat less drag quicker initial turn call snap MA Combat writer Charlie Johnson dubs flickability phenomenon caused much greater proximity moment arms model center mass farther engine and/or tail center-ofgravity longer take overcome increased inertia begin moving Since longer moments have literally farther move takes time plane rotate again stop rotating other things being equal wing load ing airfoil etc once turn estab lished turning radius flying wing will equal standard foam clone However flying wing will few degrees ahead dint having begun turn promptly ability snap turn hallmarks de sign flying wing excels point-and shoot flying thats style wing definitely way go other hand like stand toe-to-toe duking out flying multiple loops eights flying wing may well shouting wind Youd giving up flying wings particular advantages Model Loosely based Klingon Battle Cruis er Star Trek Bird Prey also re tains features 1959 flying wing Mel amij has same airfoil balanced eleva tor wing tip design developed original model Melamij won 1960 Rocky Mountain Regional Wyo ming State Championships obvious changes incorporated Prey tapered wing higher pect ratio significantly larger size airplane has grown 565 sq in cluding fantail Bird Prey scored five kills seven matches 1988 Money Nats cluding defeating eventual winner loss discrepancy count caused forfeiture after kill scored wont indicate prototypes speed particular engine prop setup used Speed will vary individual en gine fuel prop combinations Gener ally use stock Fox MK IVs Taipan 8 x 6 props Although some hotter air planes pass straight runs few outrun Heavier engines like K&B 58s Supertigre S-36 also work well Prey model size extra weight such engines has little effect flight characteristics Construction Begin cutting out parts build center wing ribs use two %-in balsa center ribs opposed 34-in rib Simply gluing two ribs gether creates greater strength single rib affords Although its optional gluing layer graphite between ribs provides further reinforcement originally built four wing center sec tions Although Ive replace wings times original center sec tions fantails alive well Glue engine mounts doubler bellcrank mount dowels Install con trol assembly dont forget install engine restraint cable use CyA cyanoac crylate wood parts Titebond foam cores number designs feature engine mounts butt against spars Since concentrates stress spar/enginemount junction setup causes countless breakages continuing mounts hind spars Ive eliminated problem Bird Prey Though its slightly heavier arrangement its also considerably stronger youre foam cutting cut wing panels using templates plans lack experience cutting foam cores isnt start Since its sharp taper makes difficult cut average core its definitely beginner Phil Cartier Corehouse supplies cores Gotcha 500 very sim ilar type used work very well use recommend Theyre available Corehouse 760 Waltonville Rd Hummelstown PA 17036 Install bladder tube outboard panel Contrary common practice put breather hole end tube top wing instead bot tom way should bladder blow can retrieve four ounces fuel want dont have dump ground Cut foam inboard panel clear control system doubler using commercial core youll need widen spar slot sure widen toward rear Cut lightening holes before stall panels Since tough job lead-out wires way heat up appropriately sized tin can melt holes out wing cores Cut outboard wing inch shorter inboard makes out board wing faster inboard keeps model light lines extra lift longer inboard wing will tend turn model toward out side circle whereas symmetrical Continued page 166 58 Model Aviation Four examples evolution Bird Prey left right Melamil dating 1959 1984 Phoenix 1987 Doombat Bird Prey latest bird has grown 565 sq Balance critical type airplane its overly touchy hunts its tail-heavy its sluggish turns its nose-heavy Properly balanced screams Photo author Peifect Stability gyro output reverse switch neutral adjust trimmer precise rudder servo neutral adjustment Airtronics SC-i Precision Ball Bearing Gyroscope System compact helicopter single axis gyro corates advanced technological features out standing ffight performance andi maneuverability Designed easy instal lation setup adjustment SC-i provides superior stability control demand ing flying conditions economically-priced gyro features ball-bearing equipped gimbal regulated gyro motor voltage supply easy mounting connector system convenient gyro setup LLYr tio N N] SEN OR in-flihtonoff operation dual ~AIRTRONICS sensitivity precision SC-i gyro GYRO MIXER BAIT automatically senses movement directs proper command 96252 appropriate servo N mixer amplifier utilizes automatic power source selector Detection Method Hall Effect Sensor SG-1 G offers perfect blend stability per formance compatibility Airtronics RIC systems Standard RONICSIA 11 Autry Irvine CA 92718714 830-s information about Airtronics quality products please call write address above Bird Prey/Baxter Continued page 58 wings being neutrally stable will continue straight last heading established modification should used Control Line model think Symmetrical wing panels made flown cir cles no outside forces encountered extra tension afforded asymmetrical wing arrangement will hold model course Cutting streamer inboard panel however can cause plane swerve circle cut spar holes through engine mounts slightly oversized way spars can removed replaced fairly easily should wings need replaced Push spars through holes center rib slide wing panels guiding lead-out wires through holes Since wing will instantly fold spars should come loose make sure theyre securely glued cores Add strapping tape trailing edge fantail can now assembled elevator hinged using favorite hinging method Slide fantail over trailing edge wing glue securely stall control horn attach pushrod Adjust pushrod controls 300 total travel Cut leading edge away clear engine add ply firewall Add wing tips ribs braces lead-out guide tubes Running lead-outs through tips creates attractive appearance Resist temptation Instead simply glue lead-out tubes bottom tip have replace wing panel leadouts can easily removed wing tip facilitate sliding new panel over lead-out wires smooth airfoil fill dents de pressions spar/foam junction Magic Model Filler light spackling com pound Cover entire plane Fas-Cal favorite low-temperature covering Adjust center-of-gravity coincide center spar sliding en gine back forth necessary Install engineand again dont forget attach restraint cable Flying Bird Prey gives predictable reliable handling no quirks catch off-guard Properly balanced model both stable responsive Like well-designed flying wing itll stantly snap turn Because its larger size Bird probably wont fast previous modelsbut youll hard-pressed find ship gives tighter turns airplane overly touchy Does hunt yes know its tail-heavy Slug gish turns Its nose heavy Does slow down bounce turns has too much control travel Adjust trim ac cordingly adding nose tail weight ad justing control travel until feels right flying style Tail weight can re duced cutting four 1 /2-in lightening holes fantail Lets see cant spark flying wing re vival Build fly Bird Prey should contention some awesome purses becoming avail able Combat matches around coun try Combat fraternity will take note Good luck happy hunting CL Scale/Boss Continued page 60 sketches three-line belicrank system setup operation Therefore will covering technical aspects three-line system oper ation Referring Sketch wing top fuselage bellcrank should placed fuselage hecause vertical location center-of-gravity model will below wing bellcrank placed wing model would have tendency roll toward center circle during flight As Gerry puts no-no since drooping control lines tend make flier turn prema turely gray cause life expectancy model extremely short should also noted high-wing mod els special lead-out guides must located some near tip inboard wing Making Continued page 168 166 Model Aviation 962S2 SG-I Gyro Specifications Power Supply 4 Cell 48 Volt common power 5 Cell 6 Volt separate power Motor Running Current 130 MA DC Amplifier Current 30 MA DC Dimensions Gyroscopel69 x 48 x 169 Miner Amp244 x 136 x 075 Control Box095x l34x 075 Weight Gyroscope254 ot Miner Ampl09 oz Control Box006 oz
Edition: Model Aviation - 1990/01
Page Numbers: 56, 57, 58, 166
Adrenalin high moment launch author controls Iauncing crew unidentified Note streamer line trail ing behind plane Lets hope doesnt tangle launch crew Also note anothr airborne plane distance trailing its streamer holes fantail seen model optional method establishing te correct center-of-gravity Photo Mike Keville Super Combat Streak Bill Netzebinds Jerkline Special models flew rery well lost favor because took longer build somewhat flimsier short profile flying wing designs Mid-decade Bill Netzeband Don Still got ball rolling direction flying wings Half Fast No Body Still winning contests early Sixties Half Fast probably successful flying wing designs fos tered such clones Wow Orbit Ace Nose Cone Although largish model 465-sq-in area diffi cult build NoBody inspired spin-offs its own T-Square Omega Ban dit among An larger flying wing design 525-sq-in Reactor too expensive serious consideration average mod eler kit sold $495 time going rate Combat models $295 $395 Flying wing models turned creditable performances Combat circles Fifties consistently winning placing IN THE 35 years since its inception Combat has never quite overcome its reputa tion fad-ridden event sort eccen tric second cousin Ironically fads begun good pilots squeezing utmost out mediocre designs Expert fliers could get away features violated sound aerodynamic principlessome fact used mainly show bellwethers rankand-file Combat modelers choices quickly imitated Though fads didnt hurt models perform ance certainly didnt help much either Several less innocent features however bred spate bad designs Innovation experimentation bywords Fifties Countless designs tried modified designers freely borrowed features other air planes early part decade squarebox-fuselage planes such Hottern Zilch Expendable All-American became popular Several box-fuselage designs cropped up culminating the Nats fell out favor early Sixties due fact didnt look like then-trendy twin-boom stabilator designs because deficiencies air twin-boom stabilator owed much its popularity influence Riley Wooten big trendmakers day Riley probably could have won Nats Ringmaster Quicker spawned development Renegade Hornet short noses long box-fuselage tails Rileys design started out plankwinged Nothin As its tail design evolved became Quicker eventually VooDoo its twin tail booms stabi lator Quicker remained top-line model early Sixties Voo Doo kitted two models probably successful Combat kits ever produced As happened Rileys airfoil what think basic flaw Because lacked between-the-ribs support covering airfoil gave inconsistent performance Designed 145% thickness airfoil produced often seemed closer 10% probably averaged about 12% Despite shortcoming Rileys design very suc cessful different fliers hands Plans above-mentioned models available through author Send SASE Barry Baxter 6490 So nora Way Cypress CA 90630 com plete listing After VooDoos success designs two booms stabilator became fad hour Bill Carpenter used three booms Swoopand anything two booms suddenly passe support ing center stabilator pushrod attached thereby removing some flex control system triple boom offered obvious struc tural advantage monoboom came along triple boom turn quickly eclipsed Though offered no particular aerody namic advantage single-boom structure did shorten building time outboard booms always nuisance cover monobooms popularity has held strong since late Sixties ad vent foam Fas-Cal Combat ships have come look basically alike Though flight characteristics vary use different wing planforms airfoil sec tions casual observer differ ences hard detect spectator contest today can easily become confused whos flying what judges have fooled airplane dont know what color streamer Foam clones have taken over todays Combat cir cle Riley Wootens designs should noted worthy imitation Rileys superb flying skills however trans formed few mediocre de signs contest winners started fads some very questionable directions Rileys uninspired designs think Guided Missile Its diamond airfoil doubt worst such design ever foisted Combat commu nity Exterminator Demon Diamond just few models adopted misbegotten airfoil Incred ibly few fliers managed rack up wins ships Makes wonder what couldve done good airplane Though diamond airfoil does have advantage being easy build straight aerodynamically its disaster center pressure wing jumps high point camber leading edge back making smooth transition impossi ble Models equipped diamond airfoils sharp leading edges such Du mas Diamond particularly awkward fliers poor stalling characteris tics planes required approximately 500 circle perform loop airfoil design begins turn angle attack increases its little better flat-plate airfoil Airfoils todays designs range very good rather bad commonly used poorer designs has very blunt almost round leading edge apex about 15-20% chord mark Though airfoils will turn well theyll also slow down process have higher stall angle drag creases much higher rate fact very high drag such airfoils induce will slow plane down several miles hour level flight drag coefficient approximately 00020 blunt flat English airfoil suf fers same disadvantage con trast elliptical leading edge 30% high point has drag coefficient 000012 Since coefficient lift al identical three shapes fliers looking speed no loss maneuver ability would benefit using ellipti cal leading edge airfoil NACA 0009 0012 0015 airfoils outstanding ex amples type airfoil After experimenting different airfoil thicknesses Ive determined anything over 15% produces too much drag Al though Stunt models use thicker airfoils airplanes differ Combat models two significant respects speed wing loading Stunt models designed wing loading approximately 12 ozIsq ft stability wind performance Theyre January 1990 57 author servicing Birds Prey preparation another match air planes very easy fast build wing all-foam because its sharp taper would best left experienced foam cutters Phil Cartier Corehouse Supplies carries cores will adapt Bird Prey Any covering will work quite well Photo Russ Wilcox pair authors Birds Note double-tapered wings angled wing tips enhance aerodynamic efficiency outboard wing cut inch shorter stock Fox MK IV engine will work quite well Heavier power plants such K&B 58 Supertigre S-36 also give ex cellent performance unduly affecting center-of-gravity Photo author also engineered fly approximately 52 sec per lap contrast Combat model has wing loading about 6 oz/sq ft generally averages about 23 sec per lap 10-ft altitude thicker airfoils seen Stunt models used sake additional lift provide high drag slows airplane down desired lap time experimenting 9% airfoil Slow Combat ship based 1958 Bill Judge design called Woody sharp leading edge found 9% thickness several drawbacks- Cornering ability suffered example after changing leading edge elliptical section ran opposite problem airplane turned too well airfoil too thin maintain adequate strength particular installation couldnt keep wing together Though havent time con tinue experiments clearly much untapped potential thinner wing unusual wing tips model functional well stylish Airflow tip airfoil will move outboard across wing attempt curve around tip high pressure area under wing low pressure above tip angle keeps pressure proper side airfoil reducing tip drag increas ing lift optimum tip angle approxi mately 150 own decade weve seen Northrop Aircrafts revival its 1940s flying wing viable bombing platform As enter 1990s think time also right bringing back Combat wing vi able streamer weapon caveat As short-tailed mod els achieving proper center-of-gravity location elevator travel critical flying wings success other hand compared standard foam clone comparable size flying wing has ad vantages somewhat less drag quicker initial turn call snap MA Combat writer Charlie Johnson dubs flickability phenomenon caused much greater proximity moment arms model center mass farther engine and/or tail center-ofgravity longer take overcome increased inertia begin moving Since longer moments have literally farther move takes time plane rotate again stop rotating other things being equal wing load ing airfoil etc once turn estab lished turning radius flying wing will equal standard foam clone However flying wing will few degrees ahead dint having begun turn promptly ability snap turn hallmarks de sign flying wing excels point-and shoot flying thats style wing definitely way go other hand like stand toe-to-toe duking out flying multiple loops eights flying wing may well shouting wind Youd giving up flying wings particular advantages Model Loosely based Klingon Battle Cruis er Star Trek Bird Prey also re tains features 1959 flying wing Mel amij has same airfoil balanced eleva tor wing tip design developed original model Melamij won 1960 Rocky Mountain Regional Wyo ming State Championships obvious changes incorporated Prey tapered wing higher pect ratio significantly larger size airplane has grown 565 sq in cluding fantail Bird Prey scored five kills seven matches 1988 Money Nats cluding defeating eventual winner loss discrepancy count caused forfeiture after kill scored wont indicate prototypes speed particular engine prop setup used Speed will vary individual en gine fuel prop combinations Gener ally use stock Fox MK IVs Taipan 8 x 6 props Although some hotter air planes pass straight runs few outrun Heavier engines like K&B 58s Supertigre S-36 also work well Prey model size extra weight such engines has little effect flight characteristics Construction Begin cutting out parts build center wing ribs use two %-in balsa center ribs opposed 34-in rib Simply gluing two ribs gether creates greater strength single rib affords Although its optional gluing layer graphite between ribs provides further reinforcement originally built four wing center sec tions Although Ive replace wings times original center sec tions fantails alive well Glue engine mounts doubler bellcrank mount dowels Install con trol assembly dont forget install engine restraint cable use CyA cyanoac crylate wood parts Titebond foam cores number designs feature engine mounts butt against spars Since concentrates stress spar/enginemount junction setup causes countless breakages continuing mounts hind spars Ive eliminated problem Bird Prey Though its slightly heavier arrangement its also considerably stronger youre foam cutting cut wing panels using templates plans lack experience cutting foam cores isnt start Since its sharp taper makes difficult cut average core its definitely beginner Phil Cartier Corehouse supplies cores Gotcha 500 very sim ilar type used work very well use recommend Theyre available Corehouse 760 Waltonville Rd Hummelstown PA 17036 Install bladder tube outboard panel Contrary common practice put breather hole end tube top wing instead bot tom way should bladder blow can retrieve four ounces fuel want dont have dump ground Cut foam inboard panel clear control system doubler using commercial core youll need widen spar slot sure widen toward rear Cut lightening holes before stall panels Since tough job lead-out wires way heat up appropriately sized tin can melt holes out wing cores Cut outboard wing inch shorter inboard makes out board wing faster inboard keeps model light lines extra lift longer inboard wing will tend turn model toward out side circle whereas symmetrical Continued page 166 58 Model Aviation Four examples evolution Bird Prey left right Melamil dating 1959 1984 Phoenix 1987 Doombat Bird Prey latest bird has grown 565 sq Balance critical type airplane its overly touchy hunts its tail-heavy its sluggish turns its nose-heavy Properly balanced screams Photo author Peifect Stability gyro output reverse switch neutral adjust trimmer precise rudder servo neutral adjustment Airtronics SC-i Precision Ball Bearing Gyroscope System compact helicopter single axis gyro corates advanced technological features out standing ffight performance andi maneuverability Designed easy instal lation setup adjustment SC-i provides superior stability control demand ing flying conditions economically-priced gyro features ball-bearing equipped gimbal regulated gyro motor voltage supply easy mounting connector system convenient gyro setup LLYr tio N N] SEN OR in-flihtonoff operation dual ~AIRTRONICS sensitivity precision SC-i gyro GYRO MIXER BAIT automatically senses movement directs proper command 96252 appropriate servo N mixer amplifier utilizes automatic power source selector Detection Method Hall Effect Sensor SG-1 G offers perfect blend stability per formance compatibility Airtronics RIC systems Standard RONICSIA 11 Autry Irvine CA 92718714 830-s information about Airtronics quality products please call write address above Bird Prey/Baxter Continued page 58 wings being neutrally stable will continue straight last heading established modification should used Control Line model think Symmetrical wing panels made flown cir cles no outside forces encountered extra tension afforded asymmetrical wing arrangement will hold model course Cutting streamer inboard panel however can cause plane swerve circle cut spar holes through engine mounts slightly oversized way spars can removed replaced fairly easily should wings need replaced Push spars through holes center rib slide wing panels guiding lead-out wires through holes Since wing will instantly fold spars should come loose make sure theyre securely glued cores Add strapping tape trailing edge fantail can now assembled elevator hinged using favorite hinging method Slide fantail over trailing edge wing glue securely stall control horn attach pushrod Adjust pushrod controls 300 total travel Cut leading edge away clear engine add ply firewall Add wing tips ribs braces lead-out guide tubes Running lead-outs through tips creates attractive appearance Resist temptation Instead simply glue lead-out tubes bottom tip have replace wing panel leadouts can easily removed wing tip facilitate sliding new panel over lead-out wires smooth airfoil fill dents de pressions spar/foam junction Magic Model Filler light spackling com pound Cover entire plane Fas-Cal favorite low-temperature covering Adjust center-of-gravity coincide center spar sliding en gine back forth necessary Install engineand again dont forget attach restraint cable Flying Bird Prey gives predictable reliable handling no quirks catch off-guard Properly balanced model both stable responsive Like well-designed flying wing itll stantly snap turn Because its larger size Bird probably wont fast previous modelsbut youll hard-pressed find ship gives tighter turns airplane overly touchy Does hunt yes know its tail-heavy Slug gish turns Its nose heavy Does slow down bounce turns has too much control travel Adjust trim ac cordingly adding nose tail weight ad justing control travel until feels right flying style Tail weight can re duced cutting four 1 /2-in lightening holes fantail Lets see cant spark flying wing re vival Build fly Bird Prey should contention some awesome purses becoming avail able Combat matches around coun try Combat fraternity will take note Good luck happy hunting CL Scale/Boss Continued page 60 sketches three-line belicrank system setup operation Therefore will covering technical aspects three-line system oper ation Referring Sketch wing top fuselage bellcrank should placed fuselage hecause vertical location center-of-gravity model will below wing bellcrank placed wing model would have tendency roll toward center circle during flight As Gerry puts no-no since drooping control lines tend make flier turn prema turely gray cause life expectancy model extremely short should also noted high-wing mod els special lead-out guides must located some near tip inboard wing Making Continued page 168 166 Model Aviation 962S2 SG-I Gyro Specifications Power Supply 4 Cell 48 Volt common power 5 Cell 6 Volt separate power Motor Running Current 130 MA DC Amplifier Current 30 MA DC Dimensions Gyroscopel69 x 48 x 169 Miner Amp244 x 136 x 075 Control Box095x l34x 075 Weight Gyroscope254 ot Miner Ampl09 oz Control Box006 oz
Edition: Model Aviation - 1990/01
Page Numbers: 56, 57, 58, 166
Adrenalin high moment launch author controls Iauncing crew unidentified Note streamer line trail ing behind plane Lets hope doesnt tangle launch crew Also note anothr airborne plane distance trailing its streamer holes fantail seen model optional method establishing te correct center-of-gravity Photo Mike Keville Super Combat Streak Bill Netzebinds Jerkline Special models flew rery well lost favor because took longer build somewhat flimsier short profile flying wing designs Mid-decade Bill Netzeband Don Still got ball rolling direction flying wings Half Fast No Body Still winning contests early Sixties Half Fast probably successful flying wing designs fos tered such clones Wow Orbit Ace Nose Cone Although largish model 465-sq-in area diffi cult build NoBody inspired spin-offs its own T-Square Omega Ban dit among An larger flying wing design 525-sq-in Reactor too expensive serious consideration average mod eler kit sold $495 time going rate Combat models $295 $395 Flying wing models turned creditable performances Combat circles Fifties consistently winning placing IN THE 35 years since its inception Combat has never quite overcome its reputa tion fad-ridden event sort eccen tric second cousin Ironically fads begun good pilots squeezing utmost out mediocre designs Expert fliers could get away features violated sound aerodynamic principlessome fact used mainly show bellwethers rankand-file Combat modelers choices quickly imitated Though fads didnt hurt models perform ance certainly didnt help much either Several less innocent features however bred spate bad designs Innovation experimentation bywords Fifties Countless designs tried modified designers freely borrowed features other air planes early part decade squarebox-fuselage planes such Hottern Zilch Expendable All-American became popular Several box-fuselage designs cropped up culminating the Nats fell out favor early Sixties due fact didnt look like then-trendy twin-boom stabilator designs because deficiencies air twin-boom stabilator owed much its popularity influence Riley Wooten big trendmakers day Riley probably could have won Nats Ringmaster Quicker spawned development Renegade Hornet short noses long box-fuselage tails Rileys design started out plankwinged Nothin As its tail design evolved became Quicker eventually VooDoo its twin tail booms stabi lator Quicker remained top-line model early Sixties Voo Doo kitted two models probably successful Combat kits ever produced As happened Rileys airfoil what think basic flaw Because lacked between-the-ribs support covering airfoil gave inconsistent performance Designed 145% thickness airfoil produced often seemed closer 10% probably averaged about 12% Despite shortcoming Rileys design very suc cessful different fliers hands Plans above-mentioned models available through author Send SASE Barry Baxter 6490 So nora Way Cypress CA 90630 com plete listing After VooDoos success designs two booms stabilator became fad hour Bill Carpenter used three booms Swoopand anything two booms suddenly passe support ing center stabilator pushrod attached thereby removing some flex control system triple boom offered obvious struc tural advantage monoboom came along triple boom turn quickly eclipsed Though offered no particular aerody namic advantage single-boom structure did shorten building time outboard booms always nuisance cover monobooms popularity has held strong since late Sixties ad vent foam Fas-Cal Combat ships have come look basically alike Though flight characteristics vary use different wing planforms airfoil sec tions casual observer differ ences hard detect spectator contest today can easily become confused whos flying what judges have fooled airplane dont know what color streamer Foam clones have taken over todays Combat cir cle Riley Wootens designs should noted worthy imitation Rileys superb flying skills however trans formed few mediocre de signs contest winners started fads some very questionable directions Rileys uninspired designs think Guided Missile Its diamond airfoil doubt worst such design ever foisted Combat commu nity Exterminator Demon Diamond just few models adopted misbegotten airfoil Incred ibly few fliers managed rack up wins ships Makes wonder what couldve done good airplane Though diamond airfoil does have advantage being easy build straight aerodynamically its disaster center pressure wing jumps high point camber leading edge back making smooth transition impossi ble Models equipped diamond airfoils sharp leading edges such Du mas Diamond particularly awkward fliers poor stalling characteris tics planes required approximately 500 circle perform loop airfoil design begins turn angle attack increases its little better flat-plate airfoil Airfoils todays designs range very good rather bad commonly used poorer designs has very blunt almost round leading edge apex about 15-20% chord mark Though airfoils will turn well theyll also slow down process have higher stall angle drag creases much higher rate fact very high drag such airfoils induce will slow plane down several miles hour level flight drag coefficient approximately 00020 blunt flat English airfoil suf fers same disadvantage con trast elliptical leading edge 30% high point has drag coefficient 000012 Since coefficient lift al identical three shapes fliers looking speed no loss maneuver ability would benefit using ellipti cal leading edge airfoil NACA 0009 0012 0015 airfoils outstanding ex amples type airfoil After experimenting different airfoil thicknesses Ive determined anything over 15% produces too much drag Al though Stunt models use thicker airfoils airplanes differ Combat models two significant respects speed wing loading Stunt models designed wing loading approximately 12 ozIsq ft stability wind performance Theyre January 1990 57 author servicing Birds Prey preparation another match air planes very easy fast build wing all-foam because its sharp taper would best left experienced foam cutters Phil Cartier Corehouse Supplies carries cores will adapt Bird Prey Any covering will work quite well Photo Russ Wilcox pair authors Birds Note double-tapered wings angled wing tips enhance aerodynamic efficiency outboard wing cut inch shorter stock Fox MK IV engine will work quite well Heavier power plants such K&B 58 Supertigre S-36 also give ex cellent performance unduly affecting center-of-gravity Photo author also engineered fly approximately 52 sec per lap contrast Combat model has wing loading about 6 oz/sq ft generally averages about 23 sec per lap 10-ft altitude thicker airfoils seen Stunt models used sake additional lift provide high drag slows airplane down desired lap time experimenting 9% airfoil Slow Combat ship based 1958 Bill Judge design called Woody sharp leading edge found 9% thickness several drawbacks- Cornering ability suffered example after changing leading edge elliptical section ran opposite problem airplane turned too well airfoil too thin maintain adequate strength particular installation couldnt keep wing together Though havent time con tinue experiments clearly much untapped potential thinner wing unusual wing tips model functional well stylish Airflow tip airfoil will move outboard across wing attempt curve around tip high pressure area under wing low pressure above tip angle keeps pressure proper side airfoil reducing tip drag increas ing lift optimum tip angle approxi mately 150 own decade weve seen Northrop Aircrafts revival its 1940s flying wing viable bombing platform As enter 1990s think time also right bringing back Combat wing vi able streamer weapon caveat As short-tailed mod els achieving proper center-of-gravity location elevator travel critical flying wings success other hand compared standard foam clone comparable size flying wing has ad vantages somewhat less drag quicker initial turn call snap MA Combat writer Charlie Johnson dubs flickability phenomenon caused much greater proximity moment arms model center mass farther engine and/or tail center-ofgravity longer take overcome increased inertia begin moving Since longer moments have literally farther move takes time plane rotate again stop rotating other things being equal wing load ing airfoil etc once turn estab lished turning radius flying wing will equal standard foam clone However flying wing will few degrees ahead dint having begun turn promptly ability snap turn hallmarks de sign flying wing excels point-and shoot flying thats style wing definitely way go other hand like stand toe-to-toe duking out flying multiple loops eights flying wing may well shouting wind Youd giving up flying wings particular advantages Model Loosely based Klingon Battle Cruis er Star Trek Bird Prey also re tains features 1959 flying wing Mel amij has same airfoil balanced eleva tor wing tip design developed original model Melamij won 1960 Rocky Mountain Regional Wyo ming State Championships obvious changes incorporated Prey tapered wing higher pect ratio significantly larger size airplane has grown 565 sq in cluding fantail Bird Prey scored five kills seven matches 1988 Money Nats cluding defeating eventual winner loss discrepancy count caused forfeiture after kill scored wont indicate prototypes speed particular engine prop setup used Speed will vary individual en gine fuel prop combinations Gener ally use stock Fox MK IVs Taipan 8 x 6 props Although some hotter air planes pass straight runs few outrun Heavier engines like K&B 58s Supertigre S-36 also work well Prey model size extra weight such engines has little effect flight characteristics Construction Begin cutting out parts build center wing ribs use two %-in balsa center ribs opposed 34-in rib Simply gluing two ribs gether creates greater strength single rib affords Although its optional gluing layer graphite between ribs provides further reinforcement originally built four wing center sec tions Although Ive replace wings times original center sec tions fantails alive well Glue engine mounts doubler bellcrank mount dowels Install con trol assembly dont forget install engine restraint cable use CyA cyanoac crylate wood parts Titebond foam cores number designs feature engine mounts butt against spars Since concentrates stress spar/enginemount junction setup causes countless breakages continuing mounts hind spars Ive eliminated problem Bird Prey Though its slightly heavier arrangement its also considerably stronger youre foam cutting cut wing panels using templates plans lack experience cutting foam cores isnt start Since its sharp taper makes difficult cut average core its definitely beginner Phil Cartier Corehouse supplies cores Gotcha 500 very sim ilar type used work very well use recommend Theyre available Corehouse 760 Waltonville Rd Hummelstown PA 17036 Install bladder tube outboard panel Contrary common practice put breather hole end tube top wing instead bot tom way should bladder blow can retrieve four ounces fuel want dont have dump ground Cut foam inboard panel clear control system doubler using commercial core youll need widen spar slot sure widen toward rear Cut lightening holes before stall panels Since tough job lead-out wires way heat up appropriately sized tin can melt holes out wing cores Cut outboard wing inch shorter inboard makes out board wing faster inboard keeps model light lines extra lift longer inboard wing will tend turn model toward out side circle whereas symmetrical Continued page 166 58 Model Aviation Four examples evolution Bird Prey left right Melamil dating 1959 1984 Phoenix 1987 Doombat Bird Prey latest bird has grown 565 sq Balance critical type airplane its overly touchy hunts its tail-heavy its sluggish turns its nose-heavy Properly balanced screams Photo author Peifect Stability gyro output reverse switch neutral adjust trimmer precise rudder servo neutral adjustment Airtronics SC-i Precision Ball Bearing Gyroscope System compact helicopter single axis gyro corates advanced technological features out standing ffight performance andi maneuverability Designed easy instal lation setup adjustment SC-i provides superior stability control demand ing flying conditions economically-priced gyro features ball-bearing equipped gimbal regulated gyro motor voltage supply easy mounting connector system convenient gyro setup LLYr tio N N] SEN OR in-flihtonoff operation dual ~AIRTRONICS sensitivity precision SC-i gyro GYRO MIXER BAIT automatically senses movement directs proper command 96252 appropriate servo N mixer amplifier utilizes automatic power source selector Detection Method Hall Effect Sensor SG-1 G offers perfect blend stability per formance compatibility Airtronics RIC systems Standard RONICSIA 11 Autry Irvine CA 92718714 830-s information about Airtronics quality products please call write address above Bird Prey/Baxter Continued page 58 wings being neutrally stable will continue straight last heading established modification should used Control Line model think Symmetrical wing panels made flown cir cles no outside forces encountered extra tension afforded asymmetrical wing arrangement will hold model course Cutting streamer inboard panel however can cause plane swerve circle cut spar holes through engine mounts slightly oversized way spars can removed replaced fairly easily should wings need replaced Push spars through holes center rib slide wing panels guiding lead-out wires through holes Since wing will instantly fold spars should come loose make sure theyre securely glued cores Add strapping tape trailing edge fantail can now assembled elevator hinged using favorite hinging method Slide fantail over trailing edge wing glue securely stall control horn attach pushrod Adjust pushrod controls 300 total travel Cut leading edge away clear engine add ply firewall Add wing tips ribs braces lead-out guide tubes Running lead-outs through tips creates attractive appearance Resist temptation Instead simply glue lead-out tubes bottom tip have replace wing panel leadouts can easily removed wing tip facilitate sliding new panel over lead-out wires smooth airfoil fill dents de pressions spar/foam junction Magic Model Filler light spackling com pound Cover entire plane Fas-Cal favorite low-temperature covering Adjust center-of-gravity coincide center spar sliding en gine back forth necessary Install engineand again dont forget attach restraint cable Flying Bird Prey gives predictable reliable handling no quirks catch off-guard Properly balanced model both stable responsive Like well-designed flying wing itll stantly snap turn Because its larger size Bird probably wont fast previous modelsbut youll hard-pressed find ship gives tighter turns airplane overly touchy Does hunt yes know its tail-heavy Slug gish turns Its nose heavy Does slow down bounce turns has too much control travel Adjust trim ac cordingly adding nose tail weight ad justing control travel until feels right flying style Tail weight can re duced cutting four 1 /2-in lightening holes fantail Lets see cant spark flying wing re vival Build fly Bird Prey should contention some awesome purses becoming avail able Combat matches around coun try Combat fraternity will take note Good luck happy hunting CL Scale/Boss Continued page 60 sketches three-line belicrank system setup operation Therefore will covering technical aspects three-line system oper ation Referring Sketch wing top fuselage bellcrank should placed fuselage hecause vertical location center-of-gravity model will below wing bellcrank placed wing model would have tendency roll toward center circle during flight As Gerry puts no-no since drooping control lines tend make flier turn prema turely gray cause life expectancy model extremely short should also noted high-wing mod els special lead-out guides must located some near tip inboard wing Making Continued page 168 166 Model Aviation 962S2 SG-I Gyro Specifications Power Supply 4 Cell 48 Volt common power 5 Cell 6 Volt separate power Motor Running Current 130 MA DC Amplifier Current 30 MA DC Dimensions Gyroscopel69 x 48 x 169 Miner Amp244 x 136 x 075 Control Box095x l34x 075 Weight Gyroscope254 ot Miner Ampl09 oz Control Box006 oz
Edition: Model Aviation - 1990/01
Page Numbers: 56, 57, 58, 166
Adrenalin high moment launch author controls Iauncing crew unidentified Note streamer line trail ing behind plane Lets hope doesnt tangle launch crew Also note anothr airborne plane distance trailing its streamer holes fantail seen model optional method establishing te correct center-of-gravity Photo Mike Keville Super Combat Streak Bill Netzebinds Jerkline Special models flew rery well lost favor because took longer build somewhat flimsier short profile flying wing designs Mid-decade Bill Netzeband Don Still got ball rolling direction flying wings Half Fast No Body Still winning contests early Sixties Half Fast probably successful flying wing designs fos tered such clones Wow Orbit Ace Nose Cone Although largish model 465-sq-in area diffi cult build NoBody inspired spin-offs its own T-Square Omega Ban dit among An larger flying wing design 525-sq-in Reactor too expensive serious consideration average mod eler kit sold $495 time going rate Combat models $295 $395 Flying wing models turned creditable performances Combat circles Fifties consistently winning placing IN THE 35 years since its inception Combat has never quite overcome its reputa tion fad-ridden event sort eccen tric second cousin Ironically fads begun good pilots squeezing utmost out mediocre designs Expert fliers could get away features violated sound aerodynamic principlessome fact used mainly show bellwethers rankand-file Combat modelers choices quickly imitated Though fads didnt hurt models perform ance certainly didnt help much either Several less innocent features however bred spate bad designs Innovation experimentation bywords Fifties Countless designs tried modified designers freely borrowed features other air planes early part decade squarebox-fuselage planes such Hottern Zilch Expendable All-American became popular Several box-fuselage designs cropped up culminating the Nats fell out favor early Sixties due fact didnt look like then-trendy twin-boom stabilator designs because deficiencies air twin-boom stabilator owed much its popularity influence Riley Wooten big trendmakers day Riley probably could have won Nats Ringmaster Quicker spawned development Renegade Hornet short noses long box-fuselage tails Rileys design started out plankwinged Nothin As its tail design evolved became Quicker eventually VooDoo its twin tail booms stabi lator Quicker remained top-line model early Sixties Voo Doo kitted two models probably successful Combat kits ever produced As happened Rileys airfoil what think basic flaw Because lacked between-the-ribs support covering airfoil gave inconsistent performance Designed 145% thickness airfoil produced often seemed closer 10% probably averaged about 12% Despite shortcoming Rileys design very suc cessful different fliers hands Plans above-mentioned models available through author Send SASE Barry Baxter 6490 So nora Way Cypress CA 90630 com plete listing After VooDoos success designs two booms stabilator became fad hour Bill Carpenter used three booms Swoopand anything two booms suddenly passe support ing center stabilator pushrod attached thereby removing some flex control system triple boom offered obvious struc tural advantage monoboom came along triple boom turn quickly eclipsed Though offered no particular aerody namic advantage single-boom structure did shorten building time outboard booms always nuisance cover monobooms popularity has held strong since late Sixties ad vent foam Fas-Cal Combat ships have come look basically alike Though flight characteristics vary use different wing planforms airfoil sec tions casual observer differ ences hard detect spectator contest today can easily become confused whos flying what judges have fooled airplane dont know what color streamer Foam clones have taken over todays Combat cir cle Riley Wootens designs should noted worthy imitation Rileys superb flying skills however trans formed few mediocre de signs contest winners started fads some very questionable directions Rileys uninspired designs think Guided Missile Its diamond airfoil doubt worst such design ever foisted Combat commu nity Exterminator Demon Diamond just few models adopted misbegotten airfoil Incred ibly few fliers managed rack up wins ships Makes wonder what couldve done good airplane Though diamond airfoil does have advantage being easy build straight aerodynamically its disaster center pressure wing jumps high point camber leading edge back making smooth transition impossi ble Models equipped diamond airfoils sharp leading edges such Du mas Diamond particularly awkward fliers poor stalling characteris tics planes required approximately 500 circle perform loop airfoil design begins turn angle attack increases its little better flat-plate airfoil Airfoils todays designs range very good rather bad commonly used poorer designs has very blunt almost round leading edge apex about 15-20% chord mark Though airfoils will turn well theyll also slow down process have higher stall angle drag creases much higher rate fact very high drag such airfoils induce will slow plane down several miles hour level flight drag coefficient approximately 00020 blunt flat English airfoil suf fers same disadvantage con trast elliptical leading edge 30% high point has drag coefficient 000012 Since coefficient lift al identical three shapes fliers looking speed no loss maneuver ability would benefit using ellipti cal leading edge airfoil NACA 0009 0012 0015 airfoils outstanding ex amples type airfoil After experimenting different airfoil thicknesses Ive determined anything over 15% produces too much drag Al though Stunt models use thicker airfoils airplanes differ Combat models two significant respects speed wing loading Stunt models designed wing loading approximately 12 ozIsq ft stability wind performance Theyre January 1990 57 author servicing Birds Prey preparation another match air planes very easy fast build wing all-foam because its sharp taper would best left experienced foam cutters Phil Cartier Corehouse Supplies carries cores will adapt Bird Prey Any covering will work quite well Photo Russ Wilcox pair authors Birds Note double-tapered wings angled wing tips enhance aerodynamic efficiency outboard wing cut inch shorter stock Fox MK IV engine will work quite well Heavier power plants such K&B 58 Supertigre S-36 also give ex cellent performance unduly affecting center-of-gravity Photo author also engineered fly approximately 52 sec per lap contrast Combat model has wing loading about 6 oz/sq ft generally averages about 23 sec per lap 10-ft altitude thicker airfoils seen Stunt models used sake additional lift provide high drag slows airplane down desired lap time experimenting 9% airfoil Slow Combat ship based 1958 Bill Judge design called Woody sharp leading edge found 9% thickness several drawbacks- Cornering ability suffered example after changing leading edge elliptical section ran opposite problem airplane turned too well airfoil too thin maintain adequate strength particular installation couldnt keep wing together Though havent time con tinue experiments clearly much untapped potential thinner wing unusual wing tips model functional well stylish Airflow tip airfoil will move outboard across wing attempt curve around tip high pressure area under wing low pressure above tip angle keeps pressure proper side airfoil reducing tip drag increas ing lift optimum tip angle approxi mately 150 own decade weve seen Northrop Aircrafts revival its 1940s flying wing viable bombing platform As enter 1990s think time also right bringing back Combat wing vi able streamer weapon caveat As short-tailed mod els achieving proper center-of-gravity location elevator travel critical flying wings success other hand compared standard foam clone comparable size flying wing has ad vantages somewhat less drag quicker initial turn call snap MA Combat writer Charlie Johnson dubs flickability phenomenon caused much greater proximity moment arms model center mass farther engine and/or tail center-ofgravity longer take overcome increased inertia begin moving Since longer moments have literally farther move takes time plane rotate again stop rotating other things being equal wing load ing airfoil etc once turn estab lished turning radius flying wing will equal standard foam clone However flying wing will few degrees ahead dint having begun turn promptly ability snap turn hallmarks de sign flying wing excels point-and shoot flying thats style wing definitely way go other hand like stand toe-to-toe duking out flying multiple loops eights flying wing may well shouting wind Youd giving up flying wings particular advantages Model Loosely based Klingon Battle Cruis er Star Trek Bird Prey also re tains features 1959 flying wing Mel amij has same airfoil balanced eleva tor wing tip design developed original model Melamij won 1960 Rocky Mountain Regional Wyo ming State Championships obvious changes incorporated Prey tapered wing higher pect ratio significantly larger size airplane has grown 565 sq in cluding fantail Bird Prey scored five kills seven matches 1988 Money Nats cluding defeating eventual winner loss discrepancy count caused forfeiture after kill scored wont indicate prototypes speed particular engine prop setup used Speed will vary individual en gine fuel prop combinations Gener ally use stock Fox MK IVs Taipan 8 x 6 props Although some hotter air planes pass straight runs few outrun Heavier engines like K&B 58s Supertigre S-36 also work well Prey model size extra weight such engines has little effect flight characteristics Construction Begin cutting out parts build center wing ribs use two %-in balsa center ribs opposed 34-in rib Simply gluing two ribs gether creates greater strength single rib affords Although its optional gluing layer graphite between ribs provides further reinforcement originally built four wing center sec tions Although Ive replace wings times original center sec tions fantails alive well Glue engine mounts doubler bellcrank mount dowels Install con trol assembly dont forget install engine restraint cable use CyA cyanoac crylate wood parts Titebond foam cores number designs feature engine mounts butt against spars Since concentrates stress spar/enginemount junction setup causes countless breakages continuing mounts hind spars Ive eliminated problem Bird Prey Though its slightly heavier arrangement its also considerably stronger youre foam cutting cut wing panels using templates plans lack experience cutting foam cores isnt start Since its sharp taper makes difficult cut average core its definitely beginner Phil Cartier Corehouse supplies cores Gotcha 500 very sim ilar type used work very well use recommend Theyre available Corehouse 760 Waltonville Rd Hummelstown PA 17036 Install bladder tube outboard panel Contrary common practice put breather hole end tube top wing instead bot tom way should bladder blow can retrieve four ounces fuel want dont have dump ground Cut foam inboard panel clear control system doubler using commercial core youll need widen spar slot sure widen toward rear Cut lightening holes before stall panels Since tough job lead-out wires way heat up appropriately sized tin can melt holes out wing cores Cut outboard wing inch shorter inboard makes out board wing faster inboard keeps model light lines extra lift longer inboard wing will tend turn model toward out side circle whereas symmetrical Continued page 166 58 Model Aviation Four examples evolution Bird Prey left right Melamil dating 1959 1984 Phoenix 1987 Doombat Bird Prey latest bird has grown 565 sq Balance critical type airplane its overly touchy hunts its tail-heavy its sluggish turns its nose-heavy Properly balanced screams Photo author Peifect Stability gyro output reverse switch neutral adjust trimmer precise rudder servo neutral adjustment Airtronics SC-i Precision Ball Bearing Gyroscope System compact helicopter single axis gyro corates advanced technological features out standing ffight performance andi maneuverability Designed easy instal lation setup adjustment SC-i provides superior stability control demand ing flying conditions economically-priced gyro features ball-bearing equipped gimbal regulated gyro motor voltage supply easy mounting connector system convenient gyro setup LLYr tio N N] SEN OR in-flihtonoff operation dual ~AIRTRONICS sensitivity precision SC-i gyro GYRO MIXER BAIT automatically senses movement directs proper command 96252 appropriate servo N mixer amplifier utilizes automatic power source selector Detection Method Hall Effect Sensor SG-1 G offers perfect blend stability per formance compatibility Airtronics RIC systems Standard RONICSIA 11 Autry Irvine CA 92718714 830-s information about Airtronics quality products please call write address above Bird Prey/Baxter Continued page 58 wings being neutrally stable will continue straight last heading established modification should used Control Line model think Symmetrical wing panels made flown cir cles no outside forces encountered extra tension afforded asymmetrical wing arrangement will hold model course Cutting streamer inboard panel however can cause plane swerve circle cut spar holes through engine mounts slightly oversized way spars can removed replaced fairly easily should wings need replaced Push spars through holes center rib slide wing panels guiding lead-out wires through holes Since wing will instantly fold spars should come loose make sure theyre securely glued cores Add strapping tape trailing edge fantail can now assembled elevator hinged using favorite hinging method Slide fantail over trailing edge wing glue securely stall control horn attach pushrod Adjust pushrod controls 300 total travel Cut leading edge away clear engine add ply firewall Add wing tips ribs braces lead-out guide tubes Running lead-outs through tips creates attractive appearance Resist temptation Instead simply glue lead-out tubes bottom tip have replace wing panel leadouts can easily removed wing tip facilitate sliding new panel over lead-out wires smooth airfoil fill dents de pressions spar/foam junction Magic Model Filler light spackling com pound Cover entire plane Fas-Cal favorite low-temperature covering Adjust center-of-gravity coincide center spar sliding en gine back forth necessary Install engineand again dont forget attach restraint cable Flying Bird Prey gives predictable reliable handling no quirks catch off-guard Properly balanced model both stable responsive Like well-designed flying wing itll stantly snap turn Because its larger size Bird probably wont fast previous modelsbut youll hard-pressed find ship gives tighter turns airplane overly touchy Does hunt yes know its tail-heavy Slug gish turns Its nose heavy Does slow down bounce turns has too much control travel Adjust trim ac cordingly adding nose tail weight ad justing control travel until feels right flying style Tail weight can re duced cutting four 1 /2-in lightening holes fantail Lets see cant spark flying wing re vival Build fly Bird Prey should contention some awesome purses becoming avail able Combat matches around coun try Combat fraternity will take note Good luck happy hunting CL Scale/Boss Continued page 60 sketches three-line belicrank system setup operation Therefore will covering technical aspects three-line system oper ation Referring Sketch wing top fuselage bellcrank should placed fuselage hecause vertical location center-of-gravity model will below wing bellcrank placed wing model would have tendency roll toward center circle during flight As Gerry puts no-no since drooping control lines tend make flier turn prema turely gray cause life expectancy model extremely short should also noted high-wing mod els special lead-out guides must located some near tip inboard wing Making Continued page 168 166 Model Aviation 962S2 SG-I Gyro Specifications Power Supply 4 Cell 48 Volt common power 5 Cell 6 Volt separate power Motor Running Current 130 MA DC Amplifier Current 30 MA DC Dimensions Gyroscopel69 x 48 x 169 Miner Amp244 x 136 x 075 Control Box095x l34x 075 Weight Gyroscope254 ot Miner Ampl09 oz Control Box006 oz