Mirage and FAItality

Sherwood Buckstaff THIS IS month Com bat freaks out have really hit luckytwo competitive airplanes price primary portion article will deal AMA Combat de sign has quite successful last five seasons additional part will cover FAT Combat plane has appeared last four Na tionals AMA plane has appeared few slightly different versions over past five years centered around con struction techniques alone have affected design characteristics plane same time has flown under variety names current name Mirage needs some explanation particu larly northern competitors mirage warm-weather phenomenon appearing occasionally cooler places Chi cago Oshkosh Daytongenerally once year August What makes mirage unique just arrive point know find no longer Enough said FAltality other hand has form name over its entire life span Before beginning background construction planes perhaps should relate some achievements Since accomplishments might convince others try designs would Nationals will confine list just Mirage 1972 Nats6th 1973 Nats5th 1974 Nats4th 1975 Natslst 1976 NatsIst FAltality 1974 Nats7th 1975 Nats3rd 1976 Natslst & 4th Obviously both designs work Now lets consider individually beginning Mirage began flying again 1972 after having anywhere around sport since 1962 found two major differ ences first obvious everyone knew what few us seemed realize ten years previously namely light airplane will decisively outfly heavy time Nationals 1962 lucky go contest find two fliers actually understood point lightness goal building procedures Wing loading What Must something combat planes can get car second change just impor tant much less obvious eye change fact Mylar films much convenient use silk dope add almost nothing structural integrity airplane Bril liantly perceptive always noticed first contest after blowing sec ond outboard wing off airplane flights After embarrassing weekend some serious soul-searching took place Did want go back silk dope no build heavy mediocre airplanes no build light strong ship sure Three four experimental planes later vertical spar born things gan fall place actual configu ration craft already estab lished have used big light planes long tail moments since 1960 saw no reason change 30 Model Aviation 16 first planes made its appearance 1972 Nationals general comment other omigod theyre light best expressed ard Rush excellent designer others wanted know plane does have currently popular much efficient high aspect ratio answer now follows have very strong motor plane perfectly built never bend airplane dirt high aspect ratio superior Lots ifs However occasionally build plane little crooked bend its quite right anymore still flyable have average motor real honker f fly hurricanes Dallas windier Chicago note wing-tip weight slip knee muddy circle primarily con cerned just staying air few seconds nice plane flying big light plane pull handle reacts also though has medium-lift airfoil combines low aspect ratio create easily flown stable forgiving aircraft plane reacts well large control move ment needed tight maneuvering because brilliant design concept because reasonably thought-out plane will same 18 oz 385 square inches Construction key ehtire construction plane vertical spar will note no full-span spars reason obvious plane breaks al invariably does near center slightly outboard center begin epoxy center rib dium-hard a vertical 1/8 bass wood spar motor mount unit prefer conventional builtup mount using maple mounts balsa may substituted run horizontal-grain center rib back spar fill verti cal-grain balsa front Either accepta ble Now cut slot bellcrank base insert epoxy rib Five-minute epoxy sufficient cause next step Drill hole insert /8 dowel running way through maple mount top bottom center rib hellcrank base used built-up mounts use another dowel near front Motor mount holes may drilled before thing else done may left until entire plane built covered ready motor mount pod stalled choose to aid balancing plane 12-in long drill bit comes very handy Glue /8 X /8 leading edge motor mount imperative leading edge spar lined up lookAugust1977 31 Two-time Nats winner Sherwood a Liking lots 0 line tension uses tip weight offset thrust asymmetrical panels ship performs just well equal panels Above Key structural design 5-part assembly Because breaks occur close center designer does use full-span spars Instead employs vertical basswood spar Below Diamond leading edge fits mount notch spar locked place thick center rib inserted mount belicrank base glues slot cut through center rib ing front must parallel view rib mount may offset unit desired engine offset Mine always just planes always have tip weight remainder airframe may built cyanoacrylates can afford technique al easy follows Using contact cement paint rib position leading edge using small brush holding ribs stacked gether paint notch will match leading edge about 1 bottom trailing edge will dries cut trailing edge chamfer inside edges rear paint both chamfered surfaces well rib location Omit ribs will touch vertical spar Once dry stick ribs leading edge lay side trailing edge table Stick down ribs beginning two tip ribs line up others put top trailing edge whole unit may picked up once Now put three ribs will touch spar Using small brush paint con tact cement approximately front 2 rib top bottom leading edge corresponding positions four sections planking building several planes once can paint once after will find first dry enough assemble build ing plane now ideal time stall controls since have wait contact cement dry will note controls use 1/32 stiff leadouts instead usual braided cable course matter preference stiff leads faster make never wear out bellcrank kink careful landing grass Also notice pushrod 075 music wire 1/16 Since plane takes greater amount control movement others 1/16 wire stiff enough Everyone Texas uses pacifier Combat instead pen bladder compartment must round does stick up spoil lines airplane Bal anced against fact bad runs rich first laps wild fuels almost unheard type compart menta Vienna sausage can wooden built-up box etcmay put last minute pen-bladder tube sist goes now Install wingtips leadout guides plank center section plane making certain aligned lead ing edgeits last chance Dont use contact cement Now comes cap-stripping Everyone hates easy way 32 Model Aviation Although Vienna sausage can does stick Out above wing accommodates pacifier tank rather pen bladder its value lies fact bad runs rich first runs rare Note leading edge carved away allow compact engine installation 0 Paint rib Sig Foam Bond same sheet soft 1/16 balsa After dries strip wood balsa stripper place end touching leading trailing edge run thumb along should stop cut off razor blade No pins no fuss Next comes everyones favorite step sanding wing have small vibrating sander makes easy block sanding work progressively down about No 400 paper Leave no edges bumps rough joints disturb airflow Cover wing FasCal equivalent soon possible after sanding before bang up Once wing covered way make sure its straight saving useless trip flying field Stick straight pin front leading edge directly centerline air foil out close wing tip same trailing edge Using flat table other surface place four drinking glasses Coke cans beer cans etc same height funny always seem use beer cans pin rests cans trailing edge approxi mately straight eye before set plane cans no visible bows etc plane ready fly sits four cans rocking stabilator select mediumhard piece 5/16 balsa plane generally light enough nose heavy dont worry about saving weight back Sand stab fairly blunt air foil shape use /8 plywood booms cause have managed past split bass booms horizontally trailing edge wrapped light glass cloth Use whichever prefer dont omit full-length piece 1/16 wire front stab have flown planes match nothing holding stab together except wire Once stab built cover same covering used wing being sure wrap around front stab wire Using very sharp new knife blade cut covering material away going glue booms pod Once epoxied dope nose booms youre ready hook up con trols go terrify people use home made aluminum horn brass tubing bushings own quick release made out piece 1/16 music wire bend pushrod correctly first place its need its unbreak able less place worry about some thing going wrong KISS Keep Sim ple Stupid Flying Start out initial test flight little movement stabilator generally use As will recall Continued page 79 CC C I CCa C LJ T -r AK C 2 Ila2 2La CCZ2 CC wCCCI- 3LaOL.C- o I- CC -jWi LJaCC CC 30 La C 0C C C.j C CC 4 2 C C o C -J CCC CD o CCC 0 C S C 0~ C C 0C - Cr 3 2 -C La La Erol [ CC C C CC CILa C C I2 Lu Ca C I]C C C I C UO CIL ViiITilLZL~ /1 2 Li I C CC C __ III _ 3 00 - dr 2 C 53C Ca CCJO OC CC 3CI-a 00CC. 00 -- H II II II II FULL-SIZE PLANS AVAILABLE SEE PAGE 96 August1977 33 C] CpJ C CC 3 early article mentioned plane needs lots control hopefully realized would nice have lots room belicrank swing may need room cause Mirage very touchy air plane own planes have slow controls can really yank again personal preference can handle plane set up following manner panicking try way done use enough con trol really pulling hard can turn super-tight half-loop loop af ter plane slows down consider ably other words put too much con trol very careful use Naturally takes careful touch slow controls unceasing attention what youre doing use full control once entire day matches saves worth feel particular design has withstood changes last five years Combat designs quite well same people snickered big fat airplane 1972 flying similar size shape planes now An advantage particular plane built light flies exceptionally well built heavier CG moves back generally happens come out ought still flies same range about 18 oz 19 oz planes weight has literally no effect Build first Hot Stuff Jet etc After fly youll want lots thats can find out nice contact cement can FAltality During summer 1973 year after unorthodox construction appeared decided build fly some 15-powered Combat planes since Oshkosh hav ing FAT Combat Having no idea what large FAI plane what small could guess proposed dimensions what actually did build planes 33 end rib end rib plus tips 8-in chord claim no real wisdom picking numbers turned out good enough design has remained unchanged throughout four full seasons flying Design weight plane has stabilized about 5 oz plane alone 11 oz motor construction standpoint major differences between FAltality large plane designed keep weight down since am quite satisfied results using building tech niques described earlier leading edge 2-in bellcrank used along 025 stiff leadouts 1/16 pushrod vertical spar used out board motor mount wooden pacifier compartment used place slightly heavier aluminum can initial flight bewarethis plane slow react build intend test fly same day brace yourself difference expect pull 15 out mud began run 15s immedi ate problem encountered keep running consistently no change setting insides outsides Anyone suffering similar problems may wish try solution use smaller pitch prop keep rpm range up use stand ard pacifier tied off much shorter ensure constant flow fuel Since switching system have still occasional minor problems stem fact area FAI gotten event engines get run about twice year Give both planes fair trial enough well acquainted characteristics put up match can now wish good luck hope dont have fly against either writing advertisers mention read about MA August1977 79 M irage/Buckstaff continued page 33

Sherwood Buckstaff THIS IS month Com bat freaks out have really hit luckytwo competitive airplanes price primary portion article will deal AMA Combat de sign has quite successful last five seasons additional part will cover FAT Combat plane has appeared last four Na tionals AMA plane has appeared few slightly different versions over past five years centered around con struction techniques alone have affected design characteristics plane same time has flown under variety names current name Mirage needs some explanation particu larly northern competitors mirage warm-weather phenomenon appearing occasionally cooler places Chi cago Oshkosh Daytongenerally once year August What makes mirage unique just arrive point know find no longer Enough said FAltality other hand has form name over its entire life span Before beginning background construction planes perhaps should relate some achievements Since accomplishments might convince others try designs would Nationals will confine list just Mirage 1972 Nats6th 1973 Nats5th 1974 Nats4th 1975 Natslst 1976 NatsIst FAltality 1974 Nats7th 1975 Nats3rd 1976 Natslst & 4th Obviously both designs work Now lets consider individually beginning Mirage began flying again 1972 after having anywhere around sport since 1962 found two major differ ences first obvious everyone knew what few us seemed realize ten years previously namely light airplane will decisively outfly heavy time Nationals 1962 lucky go contest find two fliers actually understood point lightness goal building procedures Wing loading What Must something combat planes can get car second change just impor tant much less obvious eye change fact Mylar films much convenient use silk dope add almost nothing structural integrity airplane Bril liantly perceptive always noticed first contest after blowing sec ond outboard wing off airplane flights After embarrassing weekend some serious soul-searching took place Did want go back silk dope no build heavy mediocre airplanes no build light strong ship sure Three four experimental planes later vertical spar born things gan fall place actual configu ration craft already estab lished have used big light planes long tail moments since 1960 saw no reason change 30 Model Aviation 16 first planes made its appearance 1972 Nationals general comment other omigod theyre light best expressed ard Rush excellent designer others wanted know plane does have currently popular much efficient high aspect ratio answer now follows have very strong motor plane perfectly built never bend airplane dirt high aspect ratio superior Lots ifs However occasionally build plane little crooked bend its quite right anymore still flyable have average motor real honker f fly hurricanes Dallas windier Chicago note wing-tip weight slip knee muddy circle primarily con cerned just staying air few seconds nice plane flying big light plane pull handle reacts also though has medium-lift airfoil combines low aspect ratio create easily flown stable forgiving aircraft plane reacts well large control move ment needed tight maneuvering because brilliant design concept because reasonably thought-out plane will same 18 oz 385 square inches Construction key ehtire construction plane vertical spar will note no full-span spars reason obvious plane breaks al invariably does near center slightly outboard center begin epoxy center rib dium-hard a vertical 1/8 bass wood spar motor mount unit prefer conventional builtup mount using maple mounts balsa may substituted run horizontal-grain center rib back spar fill verti cal-grain balsa front Either accepta ble Now cut slot bellcrank base insert epoxy rib Five-minute epoxy sufficient cause next step Drill hole insert /8 dowel running way through maple mount top bottom center rib hellcrank base used built-up mounts use another dowel near front Motor mount holes may drilled before thing else done may left until entire plane built covered ready motor mount pod stalled choose to aid balancing plane 12-in long drill bit comes very handy Glue /8 X /8 leading edge motor mount imperative leading edge spar lined up lookAugust1977 31 Two-time Nats winner Sherwood a Liking lots 0 line tension uses tip weight offset thrust asymmetrical panels ship performs just well equal panels Above Key structural design 5-part assembly Because breaks occur close center designer does use full-span spars Instead employs vertical basswood spar Below Diamond leading edge fits mount notch spar locked place thick center rib inserted mount belicrank base glues slot cut through center rib ing front must parallel view rib mount may offset unit desired engine offset Mine always just planes always have tip weight remainder airframe may built cyanoacrylates can afford technique al easy follows Using contact cement paint rib position leading edge using small brush holding ribs stacked gether paint notch will match leading edge about 1 bottom trailing edge will dries cut trailing edge chamfer inside edges rear paint both chamfered surfaces well rib location Omit ribs will touch vertical spar Once dry stick ribs leading edge lay side trailing edge table Stick down ribs beginning two tip ribs line up others put top trailing edge whole unit may picked up once Now put three ribs will touch spar Using small brush paint con tact cement approximately front 2 rib top bottom leading edge corresponding positions four sections planking building several planes once can paint once after will find first dry enough assemble build ing plane now ideal time stall controls since have wait contact cement dry will note controls use 1/32 stiff leadouts instead usual braided cable course matter preference stiff leads faster make never wear out bellcrank kink careful landing grass Also notice pushrod 075 music wire 1/16 Since plane takes greater amount control movement others 1/16 wire stiff enough Everyone Texas uses pacifier Combat instead pen bladder compartment must round does stick up spoil lines airplane Bal anced against fact bad runs rich first laps wild fuels almost unheard type compart menta Vienna sausage can wooden built-up box etcmay put last minute pen-bladder tube sist goes now Install wingtips leadout guides plank center section plane making certain aligned lead ing edgeits last chance Dont use contact cement Now comes cap-stripping Everyone hates easy way 32 Model Aviation Although Vienna sausage can does stick Out above wing accommodates pacifier tank rather pen bladder its value lies fact bad runs rich first runs rare Note leading edge carved away allow compact engine installation 0 Paint rib Sig Foam Bond same sheet soft 1/16 balsa After dries strip wood balsa stripper place end touching leading trailing edge run thumb along should stop cut off razor blade No pins no fuss Next comes everyones favorite step sanding wing have small vibrating sander makes easy block sanding work progressively down about No 400 paper Leave no edges bumps rough joints disturb airflow Cover wing FasCal equivalent soon possible after sanding before bang up Once wing covered way make sure its straight saving useless trip flying field Stick straight pin front leading edge directly centerline air foil out close wing tip same trailing edge Using flat table other surface place four drinking glasses Coke cans beer cans etc same height funny always seem use beer cans pin rests cans trailing edge approxi mately straight eye before set plane cans no visible bows etc plane ready fly sits four cans rocking stabilator select mediumhard piece 5/16 balsa plane generally light enough nose heavy dont worry about saving weight back Sand stab fairly blunt air foil shape use /8 plywood booms cause have managed past split bass booms horizontally trailing edge wrapped light glass cloth Use whichever prefer dont omit full-length piece 1/16 wire front stab have flown planes match nothing holding stab together except wire Once stab built cover same covering used wing being sure wrap around front stab wire Using very sharp new knife blade cut covering material away going glue booms pod Once epoxied dope nose booms youre ready hook up con trols go terrify people use home made aluminum horn brass tubing bushings own quick release made out piece 1/16 music wire bend pushrod correctly first place its need its unbreak able less place worry about some thing going wrong KISS Keep Sim ple Stupid Flying Start out initial test flight little movement stabilator generally use As will recall Continued page 79 CC C I CCa C LJ T -r AK C 2 Ila2 2La CCZ2 CC wCCCI- 3LaOL.C- o I- CC -jWi LJaCC CC 30 La C 0C C C.j C CC 4 2 C C o C -J CCC CD o CCC 0 C S C 0~ C C 0C - Cr 3 2 -C La La Erol [ CC C C CC CILa C C I2 Lu Ca C I]C C C I C UO CIL ViiITilLZL~ /1 2 Li I C CC C __ III _ 3 00 - dr 2 C 53C Ca CCJO OC CC 3CI-a 00CC. 00 -- H II II II II FULL-SIZE PLANS AVAILABLE SEE PAGE 96 August1977 33 C] CpJ C CC 3 early article mentioned plane needs lots control hopefully realized would nice have lots room belicrank swing may need room cause Mirage very touchy air plane own planes have slow controls can really yank again personal preference can handle plane set up following manner panicking try way done use enough con trol really pulling hard can turn super-tight half-loop loop af ter plane slows down consider ably other words put too much con trol very careful use Naturally takes careful touch slow controls unceasing attention what youre doing use full control once entire day matches saves worth feel particular design has withstood changes last five years Combat designs quite well same people snickered big fat airplane 1972 flying similar size shape planes now An advantage particular plane built light flies exceptionally well built heavier CG moves back generally happens come out ought still flies same range about 18 oz 19 oz planes weight has literally no effect Build first Hot Stuff Jet etc After fly youll want lots thats can find out nice contact cement can FAltality During summer 1973 year after unorthodox construction appeared decided build fly some 15-powered Combat planes since Oshkosh hav ing FAT Combat Having no idea what large FAI plane what small could guess proposed dimensions what actually did build planes 33 end rib end rib plus tips 8-in chord claim no real wisdom picking numbers turned out good enough design has remained unchanged throughout four full seasons flying Design weight plane has stabilized about 5 oz plane alone 11 oz motor construction standpoint major differences between FAltality large plane designed keep weight down since am quite satisfied results using building tech niques described earlier leading edge 2-in bellcrank used along 025 stiff leadouts 1/16 pushrod vertical spar used out board motor mount wooden pacifier compartment used place slightly heavier aluminum can initial flight bewarethis plane slow react build intend test fly same day brace yourself difference expect pull 15 out mud began run 15s immedi ate problem encountered keep running consistently no change setting insides outsides Anyone suffering similar problems may wish try solution use smaller pitch prop keep rpm range up use stand ard pacifier tied off much shorter ensure constant flow fuel Since switching system have still occasional minor problems stem fact area FAI gotten event engines get run about twice year Give both planes fair trial enough well acquainted characteristics put up match can now wish good luck hope dont have fly against either writing advertisers mention read about MA August1977 79 M irage/Buckstaff continued page 33