Free Flight DURA TION Bob Meuser STRANGE configuration saw photo wind-tunnel model similar shown sketch being tested Langley Re search Center Thinking might have some conceivable relation Free Flight model ing checked out chief technical consultant W Hewitt Phillips As configuration originally envi sioned Julian Walkowitz engineer Wright Patterson AFB wing tail joined tips high-aspect-ratio surfaces idea wing tail would brace other giving stiffer structure hence higher flutter speed However stiffness increase nearly great its truss-like front-view appear ance would lead believe Raise nose bit whole thing suddenly becomes lot thinner idea applied somewhat modified form Burt Rutan proposed agricultural aircraft looking somewhat like sketch wind-tunnel tests done primarily obtain stability data rather lift-drag data seems obvious induced drag would less monoplane same span because biplane effect Marginal longitudinal stability required re ducing sweep horizontal tail outboard end tail attached wing means pod extending behind wing Directional stability suf fered because tunnel effect wing-tail combination airflow acting fin putting some fin area above point horizontal tail attaches would cure Hewitt thinks idea worth some experimentationPennyplane perhaps will replace long-tail-boom conventional configuration com petition Free Flight applications Hot engines Nat Comfort Richmond VA suggests Free Flighters might well pay attention Control Line Com bat lads Nats engine started out life OS 25 FSR ABC RC persuasion reworked Combat-style Dick Tyndall well known Eastern Com bat circles Aside obvious custom venturi remote needle valve mount Champs second place Nats little things done engines Tyndall does business under name innards powered Nats Shocer first Virginia Craftsman 348 Argyll Circle place Eastern US Free Flight Highland Springs VA 23075 60 Model Aviation wouldnt want competition Free Flighters miss out good thing though Product Review item July 1983 issue page 56 again Thomas Kosters digital OT timer Since one-function device useful Towline Gliders complete system appears above start switch activated towline release timer Ni-Cd battery pack Below have good look timer itself Note time-set rotary switches settable 6-sec intervals 6 sec 9 mm 54 sec Three holes between switches charging plug Wire swing-arm released solenoid column Competition FF models win better HOT engines Nat Comtorts O as custom jeajures tuning suitable CL Combat Virginia Craftsman won Nets column Koster does again Several years back Thomas Koster three-time World Champ Free Flight events perfected marketed rather expensive digital multi-function timer FAT Power models recently introduced much less expensive singlefunction timer Nordic Towline Gliders See photo timing de thermalizer function accomplished ro tating pair tiny waterproof switches Time can set steps 6 sec zero 9 mm 54 sec accurate 001 percent single arm held latch released actuation sole noid no possibility putting arm wrong notch scroll because isnt scroll unit powered Ni-Cd battery can trickle-charged between flights wait Thats super-cautious Koster claims battery will last 100 actuations between charges Weights timer 18 grams battery 17 grams Prices timer battery start switch $55 trickle charger $30 Source Koster Digital PO Box 54 DK-3400 Hill erod Denmark Towline release photo shows simple type towline release mechanism usable wherever twang-hook might otherwise used comes us Bob Lieber way Doe Jackson little bent wire part per manently attached towhook mechan ism aircraft normally used secure buttons commercial garments such lab coats wire loop attached end towline diameter wire determines tension wire loop disengages button retainer mechanism button retainer attached could simple swinging arm During tow arm would pulled forward line between arm rudder horn would pull rudder straight towline tension re leased rubberband spring oppo site rudder horn would pull rudder circle-tow position separate pull-pin tached short string end towline would set glide position rudder start DT timer New wheels Peck-Polymers famous world wide its Peanut Scale kits plans Hannan others sorts fun-type Continued page 154 January 1984 61 Would believe bench-test setup tricky Towline Glider towhook Wire loop attaches end towline pulls free commercial metal Clip attached model Thickness wire loop determines ten slon line release Peck-Polymers has some molded-plastic wheels rubber models light light light TIGER TAIL 4 Ron Chidgeys latest A best series little larger lighter slower retains honest flight character tistics its predecessors Especially recommended sportsman ad vanced pattern also good choice tor turn-around pattern Plans construction hints -$995 WELLER 3 BLADE PROP very stiff molded fiberglas propellor trom England Its efficient design allows substantial reduction noise level actually improving per formance $2000 NEW CLAMP IT FOREVER STAINLESS STEEL PIPE CLAMPS Light strong Low-profile seiflocking 3116 width wont cut silicone couplers Pkg 4 clamps -$295 flights Persuader weights 33 oz cobalt 05 motor six 12 Ah cells three servos Receivers generally weigh between 1 2 oz some planes remove plastic case save about neaky overweight item flight pack can wiring harness Some surprisingly heavy large switches complete bulky plastic covers lots wire Try some thing lighter Radio installation Electrics relatively easy since minimal vibration usually light mechanical loads Ive elimi nated foam packing am getting away servo rails trays smaller planes double-sticky foam servo mounting tape double sticky Velcro Radio Shack holds servos receiver flight battery attaching double stickies balsa first coat balsa model airplane cement such Ambroid let dry fill wood make sound surface sticky stick case servos stock fuselage sides opposite other put light balsa foam block between keep servos presssed sides prevent rocking pushrod loads feel comfortable con ventional servo-mounting techniques sug gest making servo tray out /v-in Lite Ply using tray sort horizon tal fuselage former during assembly does wonders alignment like Golden Rod small balsa pushrods planes 3/i sq firm balsa rods work very well bind end heavy thread drill #50 hole end center Thread hole 2-56 tap put CyA threads Retap standard pushrod fittings can screwed inadjustable too least weight maximize use pushrod mate rial minimize length metal fitNEW NEW WING TUBE & SOCKETS 1 dia aluminum alloy tubing plug wings Included pair special slip-fit phenolic sockets build wing-structure 2024 alum tube 24 long socket 12 long S8951se1 / - Sleeve Puller -$795 Bearing Puller -$695 ENGINE SLEEVE & BEARING PULLER Pull tight sleeves bearings easily damage Cone cone expanding brass ring grips sleeve bearing ID new 60s 17MM rear bearing *Special* Both $1395 See Dealer Order Direct Include 75 Per Item f UPS Gator RIC Products Pompano Dr G3713 P ensacolaFL 32514 Phone AC t904 476-8639 tings end suggest think terms quarter ounces Four make up ounce four make up quarter-pounder 4 Installation weight purpose following information give some preliminary guidelines examples elec tric power system weight Part 7 well look finished plane weight size power flight times As general rule thumb weight power system motor battery wiring switch prop typical RC Electric about 50% total_place weightwith range limits usually between 40% 60% radio plane make up rest total Table shows some examples As further guideline electricpowered gliders generally have wing load ings 10-11 oz/sq ft aerobatics ships range 12-22 sport Scale about 12-14 Well look particulars future section cant wait can work backwards estimate wing area examples Table 1 5 Look pictures sketchesand compare examples text Since come installations next month should keep part handy another look time Also some illus trations coming up Section B can viewed standpoint text well Speaving next month youll find Part 6 loaded detailed information other things needed make installation completeswitches connectors fuses wir ing etc After well discuss planes flying previous parts will come together fairly extensive tabulation known performers complete statisti cal performance information 154 Model Aviation plan wrap up sorts most-often-asked questions will reviewed Also some incidentals oversights throughout will included may wondering Spectra construction article still planned conclusion series Its just end near once perceived Please forward questions SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 realize have times past should have responded bit faster apologize However continue resolute intent answer expedient fashion conditions permitting FF Duration/Meuser Continued paoe 61 models sorts parts accessories miscellaneous goodies small rubberpower CO-2 power models has just troduced new line molded plastic wheels Molded mind vacuumformed As result detail crystalclear neatly-reinforced builtin hub Three sizes currently available hope therell 3/4 diameters weighing respectively 04 06 07 grams price 99tt pack eight size Actually wheel sort halfwheel flip side concave used as-is look pretty good Scale buffs will quick realize look lot realistic two wheels glued together back-to-back way come out rather fat-looking just right some applications prefer thinner look just scrub wheel around piece 80-grit garnet paper few sec onds before gluing halves together dont like looks six-spoke hub glue paper disc pattern preference local dealer doesnt carry tell him Meuser says hes shmoe order direct Peck send $150 Pecks larger-than-ever catalog address PO Box 2498 -La Mesa CA 92041 As sort gentle hint theyd like business catalog comes free first order word wise - Miter boxes revisited Ive published sev eral methods cutting gussets using special home-brew jigs Nat Comfort expressed amusement seeing modelers make such elaborate efforts perform such simple operation points out modelers already own razor saw small miter boxes available X-Acto FAI Model Supply others Using balsa stripstock appropriate size flip-cutflip-cut sequence can up ears gussets watching evening news So whats fuss Well building Half-A larger model using medium-to-hard balsa saw will cut neatly gumming NEW death content equal-leg gus sets what Nat says absolutely true Since description must cover least 90% Free Flight models apologize reminding about humble razor saw off-the-shelf miter box smaller gussetsand especially soft balsathe use single-edge razor blade appropriate razor saw some home-brew miter boxeswhich what arecome play Also scheme showed cutting unequal-leg gussets de sired proportions Nordic Glider trailing edges example undercambered ribs tend mite weak unequal-leg gussets have slight advantage long leg glued side rib Bob Meuser 4200 Gregory St Oakland CA 94619 FF Indoor/Tenny Continued page 62 Testing methods best-doc umented tests model rubber de veloped Fred Pearce test consisted stretching loop rubber about eight times normal length holding extension three minutes recording exten sion loop relaxed few inches time tension measured relaxation interval 5 example length rubber will have carefully measured its weight recorded pounds force tension has re corded relaxation interval force readings summed Fred Wakefield flier Dennis Jaecks decided refine method door Dennis describes testing way I Stretch test loop rubber until tension equals force Fl Fl computed formula Fl rubber weight grams loop length inches 2 3 Record loop length LI force Fl Stretch loop again force F2 F2 430 X rubber wt gin Ll 4 Record loop length L2 force F2 5 Relax loop 3 record force F3 6 Continue relax stretch 3 record force 7 Calculate energy stored sum ming following series F2F3 . 2 2 FnlFn 2 Finally compute energy storage E ft-lb/lb using F t x 16 x force summation Continued page 158 L- C Jee3 what dri Jrni 5f January 1984 155
Edition: Model Aviation - 1984/01
Page Numbers: 60, 61, 154, 155
Free Flight DURA TION Bob Meuser STRANGE configuration saw photo wind-tunnel model similar shown sketch being tested Langley Re search Center Thinking might have some conceivable relation Free Flight model ing checked out chief technical consultant W Hewitt Phillips As configuration originally envi sioned Julian Walkowitz engineer Wright Patterson AFB wing tail joined tips high-aspect-ratio surfaces idea wing tail would brace other giving stiffer structure hence higher flutter speed However stiffness increase nearly great its truss-like front-view appear ance would lead believe Raise nose bit whole thing suddenly becomes lot thinner idea applied somewhat modified form Burt Rutan proposed agricultural aircraft looking somewhat like sketch wind-tunnel tests done primarily obtain stability data rather lift-drag data seems obvious induced drag would less monoplane same span because biplane effect Marginal longitudinal stability required re ducing sweep horizontal tail outboard end tail attached wing means pod extending behind wing Directional stability suf fered because tunnel effect wing-tail combination airflow acting fin putting some fin area above point horizontal tail attaches would cure Hewitt thinks idea worth some experimentationPennyplane perhaps will replace long-tail-boom conventional configuration com petition Free Flight applications Hot engines Nat Comfort Richmond VA suggests Free Flighters might well pay attention Control Line Com bat lads Nats engine started out life OS 25 FSR ABC RC persuasion reworked Combat-style Dick Tyndall well known Eastern Com bat circles Aside obvious custom venturi remote needle valve mount Champs second place Nats little things done engines Tyndall does business under name innards powered Nats Shocer first Virginia Craftsman 348 Argyll Circle place Eastern US Free Flight Highland Springs VA 23075 60 Model Aviation wouldnt want competition Free Flighters miss out good thing though Product Review item July 1983 issue page 56 again Thomas Kosters digital OT timer Since one-function device useful Towline Gliders complete system appears above start switch activated towline release timer Ni-Cd battery pack Below have good look timer itself Note time-set rotary switches settable 6-sec intervals 6 sec 9 mm 54 sec Three holes between switches charging plug Wire swing-arm released solenoid column Competition FF models win better HOT engines Nat Comtorts O as custom jeajures tuning suitable CL Combat Virginia Craftsman won Nets column Koster does again Several years back Thomas Koster three-time World Champ Free Flight events perfected marketed rather expensive digital multi-function timer FAT Power models recently introduced much less expensive singlefunction timer Nordic Towline Gliders See photo timing de thermalizer function accomplished ro tating pair tiny waterproof switches Time can set steps 6 sec zero 9 mm 54 sec accurate 001 percent single arm held latch released actuation sole noid no possibility putting arm wrong notch scroll because isnt scroll unit powered Ni-Cd battery can trickle-charged between flights wait Thats super-cautious Koster claims battery will last 100 actuations between charges Weights timer 18 grams battery 17 grams Prices timer battery start switch $55 trickle charger $30 Source Koster Digital PO Box 54 DK-3400 Hill erod Denmark Towline release photo shows simple type towline release mechanism usable wherever twang-hook might otherwise used comes us Bob Lieber way Doe Jackson little bent wire part per manently attached towhook mechan ism aircraft normally used secure buttons commercial garments such lab coats wire loop attached end towline diameter wire determines tension wire loop disengages button retainer mechanism button retainer attached could simple swinging arm During tow arm would pulled forward line between arm rudder horn would pull rudder straight towline tension re leased rubberband spring oppo site rudder horn would pull rudder circle-tow position separate pull-pin tached short string end towline would set glide position rudder start DT timer New wheels Peck-Polymers famous world wide its Peanut Scale kits plans Hannan others sorts fun-type Continued page 154 January 1984 61 Would believe bench-test setup tricky Towline Glider towhook Wire loop attaches end towline pulls free commercial metal Clip attached model Thickness wire loop determines ten slon line release Peck-Polymers has some molded-plastic wheels rubber models light light light TIGER TAIL 4 Ron Chidgeys latest A best series little larger lighter slower retains honest flight character tistics its predecessors Especially recommended sportsman ad vanced pattern also good choice tor turn-around pattern Plans construction hints -$995 WELLER 3 BLADE PROP very stiff molded fiberglas propellor trom England Its efficient design allows substantial reduction noise level actually improving per formance $2000 NEW CLAMP IT FOREVER STAINLESS STEEL PIPE CLAMPS Light strong Low-profile seiflocking 3116 width wont cut silicone couplers Pkg 4 clamps -$295 flights Persuader weights 33 oz cobalt 05 motor six 12 Ah cells three servos Receivers generally weigh between 1 2 oz some planes remove plastic case save about neaky overweight item flight pack can wiring harness Some surprisingly heavy large switches complete bulky plastic covers lots wire Try some thing lighter Radio installation Electrics relatively easy since minimal vibration usually light mechanical loads Ive elimi nated foam packing am getting away servo rails trays smaller planes double-sticky foam servo mounting tape double sticky Velcro Radio Shack holds servos receiver flight battery attaching double stickies balsa first coat balsa model airplane cement such Ambroid let dry fill wood make sound surface sticky stick case servos stock fuselage sides opposite other put light balsa foam block between keep servos presssed sides prevent rocking pushrod loads feel comfortable con ventional servo-mounting techniques sug gest making servo tray out /v-in Lite Ply using tray sort horizon tal fuselage former during assembly does wonders alignment like Golden Rod small balsa pushrods planes 3/i sq firm balsa rods work very well bind end heavy thread drill #50 hole end center Thread hole 2-56 tap put CyA threads Retap standard pushrod fittings can screwed inadjustable too least weight maximize use pushrod mate rial minimize length metal fitNEW NEW WING TUBE & SOCKETS 1 dia aluminum alloy tubing plug wings Included pair special slip-fit phenolic sockets build wing-structure 2024 alum tube 24 long socket 12 long S8951se1 / - Sleeve Puller -$795 Bearing Puller -$695 ENGINE SLEEVE & BEARING PULLER Pull tight sleeves bearings easily damage Cone cone expanding brass ring grips sleeve bearing ID new 60s 17MM rear bearing *Special* Both $1395 See Dealer Order Direct Include 75 Per Item f UPS Gator RIC Products Pompano Dr G3713 P ensacolaFL 32514 Phone AC t904 476-8639 tings end suggest think terms quarter ounces Four make up ounce four make up quarter-pounder 4 Installation weight purpose following information give some preliminary guidelines examples elec tric power system weight Part 7 well look finished plane weight size power flight times As general rule thumb weight power system motor battery wiring switch prop typical RC Electric about 50% total_place weightwith range limits usually between 40% 60% radio plane make up rest total Table shows some examples As further guideline electricpowered gliders generally have wing load ings 10-11 oz/sq ft aerobatics ships range 12-22 sport Scale about 12-14 Well look particulars future section cant wait can work backwards estimate wing area examples Table 1 5 Look pictures sketchesand compare examples text Since come installations next month should keep part handy another look time Also some illus trations coming up Section B can viewed standpoint text well Speaving next month youll find Part 6 loaded detailed information other things needed make installation completeswitches connectors fuses wir ing etc After well discuss planes flying previous parts will come together fairly extensive tabulation known performers complete statisti cal performance information 154 Model Aviation plan wrap up sorts most-often-asked questions will reviewed Also some incidentals oversights throughout will included may wondering Spectra construction article still planned conclusion series Its just end near once perceived Please forward questions SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 realize have times past should have responded bit faster apologize However continue resolute intent answer expedient fashion conditions permitting FF Duration/Meuser Continued paoe 61 models sorts parts accessories miscellaneous goodies small rubberpower CO-2 power models has just troduced new line molded plastic wheels Molded mind vacuumformed As result detail crystalclear neatly-reinforced builtin hub Three sizes currently available hope therell 3/4 diameters weighing respectively 04 06 07 grams price 99tt pack eight size Actually wheel sort halfwheel flip side concave used as-is look pretty good Scale buffs will quick realize look lot realistic two wheels glued together back-to-back way come out rather fat-looking just right some applications prefer thinner look just scrub wheel around piece 80-grit garnet paper few sec onds before gluing halves together dont like looks six-spoke hub glue paper disc pattern preference local dealer doesnt carry tell him Meuser says hes shmoe order direct Peck send $150 Pecks larger-than-ever catalog address PO Box 2498 -La Mesa CA 92041 As sort gentle hint theyd like business catalog comes free first order word wise - Miter boxes revisited Ive published sev eral methods cutting gussets using special home-brew jigs Nat Comfort expressed amusement seeing modelers make such elaborate efforts perform such simple operation points out modelers already own razor saw small miter boxes available X-Acto FAI Model Supply others Using balsa stripstock appropriate size flip-cutflip-cut sequence can up ears gussets watching evening news So whats fuss Well building Half-A larger model using medium-to-hard balsa saw will cut neatly gumming NEW death content equal-leg gus sets what Nat says absolutely true Since description must cover least 90% Free Flight models apologize reminding about humble razor saw off-the-shelf miter box smaller gussetsand especially soft balsathe use single-edge razor blade appropriate razor saw some home-brew miter boxeswhich what arecome play Also scheme showed cutting unequal-leg gussets de sired proportions Nordic Glider trailing edges example undercambered ribs tend mite weak unequal-leg gussets have slight advantage long leg glued side rib Bob Meuser 4200 Gregory St Oakland CA 94619 FF Indoor/Tenny Continued page 62 Testing methods best-doc umented tests model rubber de veloped Fred Pearce test consisted stretching loop rubber about eight times normal length holding extension three minutes recording exten sion loop relaxed few inches time tension measured relaxation interval 5 example length rubber will have carefully measured its weight recorded pounds force tension has re corded relaxation interval force readings summed Fred Wakefield flier Dennis Jaecks decided refine method door Dennis describes testing way I Stretch test loop rubber until tension equals force Fl Fl computed formula Fl rubber weight grams loop length inches 2 3 Record loop length LI force Fl Stretch loop again force F2 F2 430 X rubber wt gin Ll 4 Record loop length L2 force F2 5 Relax loop 3 record force F3 6 Continue relax stretch 3 record force 7 Calculate energy stored sum ming following series F2F3 . 2 2 FnlFn 2 Finally compute energy storage E ft-lb/lb using F t x 16 x force summation Continued page 158 L- C Jee3 what dri Jrni 5f January 1984 155
Edition: Model Aviation - 1984/01
Page Numbers: 60, 61, 154, 155
Free Flight DURA TION Bob Meuser STRANGE configuration saw photo wind-tunnel model similar shown sketch being tested Langley Re search Center Thinking might have some conceivable relation Free Flight model ing checked out chief technical consultant W Hewitt Phillips As configuration originally envi sioned Julian Walkowitz engineer Wright Patterson AFB wing tail joined tips high-aspect-ratio surfaces idea wing tail would brace other giving stiffer structure hence higher flutter speed However stiffness increase nearly great its truss-like front-view appear ance would lead believe Raise nose bit whole thing suddenly becomes lot thinner idea applied somewhat modified form Burt Rutan proposed agricultural aircraft looking somewhat like sketch wind-tunnel tests done primarily obtain stability data rather lift-drag data seems obvious induced drag would less monoplane same span because biplane effect Marginal longitudinal stability required re ducing sweep horizontal tail outboard end tail attached wing means pod extending behind wing Directional stability suf fered because tunnel effect wing-tail combination airflow acting fin putting some fin area above point horizontal tail attaches would cure Hewitt thinks idea worth some experimentationPennyplane perhaps will replace long-tail-boom conventional configuration com petition Free Flight applications Hot engines Nat Comfort Richmond VA suggests Free Flighters might well pay attention Control Line Com bat lads Nats engine started out life OS 25 FSR ABC RC persuasion reworked Combat-style Dick Tyndall well known Eastern Com bat circles Aside obvious custom venturi remote needle valve mount Champs second place Nats little things done engines Tyndall does business under name innards powered Nats Shocer first Virginia Craftsman 348 Argyll Circle place Eastern US Free Flight Highland Springs VA 23075 60 Model Aviation wouldnt want competition Free Flighters miss out good thing though Product Review item July 1983 issue page 56 again Thomas Kosters digital OT timer Since one-function device useful Towline Gliders complete system appears above start switch activated towline release timer Ni-Cd battery pack Below have good look timer itself Note time-set rotary switches settable 6-sec intervals 6 sec 9 mm 54 sec Three holes between switches charging plug Wire swing-arm released solenoid column Competition FF models win better HOT engines Nat Comtorts O as custom jeajures tuning suitable CL Combat Virginia Craftsman won Nets column Koster does again Several years back Thomas Koster three-time World Champ Free Flight events perfected marketed rather expensive digital multi-function timer FAT Power models recently introduced much less expensive singlefunction timer Nordic Towline Gliders See photo timing de thermalizer function accomplished ro tating pair tiny waterproof switches Time can set steps 6 sec zero 9 mm 54 sec accurate 001 percent single arm held latch released actuation sole noid no possibility putting arm wrong notch scroll because isnt scroll unit powered Ni-Cd battery can trickle-charged between flights wait Thats super-cautious Koster claims battery will last 100 actuations between charges Weights timer 18 grams battery 17 grams Prices timer battery start switch $55 trickle charger $30 Source Koster Digital PO Box 54 DK-3400 Hill erod Denmark Towline release photo shows simple type towline release mechanism usable wherever twang-hook might otherwise used comes us Bob Lieber way Doe Jackson little bent wire part per manently attached towhook mechan ism aircraft normally used secure buttons commercial garments such lab coats wire loop attached end towline diameter wire determines tension wire loop disengages button retainer mechanism button retainer attached could simple swinging arm During tow arm would pulled forward line between arm rudder horn would pull rudder straight towline tension re leased rubberband spring oppo site rudder horn would pull rudder circle-tow position separate pull-pin tached short string end towline would set glide position rudder start DT timer New wheels Peck-Polymers famous world wide its Peanut Scale kits plans Hannan others sorts fun-type Continued page 154 January 1984 61 Would believe bench-test setup tricky Towline Glider towhook Wire loop attaches end towline pulls free commercial metal Clip attached model Thickness wire loop determines ten slon line release Peck-Polymers has some molded-plastic wheels rubber models light light light TIGER TAIL 4 Ron Chidgeys latest A best series little larger lighter slower retains honest flight character tistics its predecessors Especially recommended sportsman ad vanced pattern also good choice tor turn-around pattern Plans construction hints -$995 WELLER 3 BLADE PROP very stiff molded fiberglas propellor trom England Its efficient design allows substantial reduction noise level actually improving per formance $2000 NEW CLAMP IT FOREVER STAINLESS STEEL PIPE CLAMPS Light strong Low-profile seiflocking 3116 width wont cut silicone couplers Pkg 4 clamps -$295 flights Persuader weights 33 oz cobalt 05 motor six 12 Ah cells three servos Receivers generally weigh between 1 2 oz some planes remove plastic case save about neaky overweight item flight pack can wiring harness Some surprisingly heavy large switches complete bulky plastic covers lots wire Try some thing lighter Radio installation Electrics relatively easy since minimal vibration usually light mechanical loads Ive elimi nated foam packing am getting away servo rails trays smaller planes double-sticky foam servo mounting tape double sticky Velcro Radio Shack holds servos receiver flight battery attaching double stickies balsa first coat balsa model airplane cement such Ambroid let dry fill wood make sound surface sticky stick case servos stock fuselage sides opposite other put light balsa foam block between keep servos presssed sides prevent rocking pushrod loads feel comfortable con ventional servo-mounting techniques sug gest making servo tray out /v-in Lite Ply using tray sort horizon tal fuselage former during assembly does wonders alignment like Golden Rod small balsa pushrods planes 3/i sq firm balsa rods work very well bind end heavy thread drill #50 hole end center Thread hole 2-56 tap put CyA threads Retap standard pushrod fittings can screwed inadjustable too least weight maximize use pushrod mate rial minimize length metal fitNEW NEW WING TUBE & SOCKETS 1 dia aluminum alloy tubing plug wings Included pair special slip-fit phenolic sockets build wing-structure 2024 alum tube 24 long socket 12 long S8951se1 / - Sleeve Puller -$795 Bearing Puller -$695 ENGINE SLEEVE & BEARING PULLER Pull tight sleeves bearings easily damage Cone cone expanding brass ring grips sleeve bearing ID new 60s 17MM rear bearing *Special* Both $1395 See Dealer Order Direct Include 75 Per Item f UPS Gator RIC Products Pompano Dr G3713 P ensacolaFL 32514 Phone AC t904 476-8639 tings end suggest think terms quarter ounces Four make up ounce four make up quarter-pounder 4 Installation weight purpose following information give some preliminary guidelines examples elec tric power system weight Part 7 well look finished plane weight size power flight times As general rule thumb weight power system motor battery wiring switch prop typical RC Electric about 50% total_place weightwith range limits usually between 40% 60% radio plane make up rest total Table shows some examples As further guideline electricpowered gliders generally have wing load ings 10-11 oz/sq ft aerobatics ships range 12-22 sport Scale about 12-14 Well look particulars future section cant wait can work backwards estimate wing area examples Table 1 5 Look pictures sketchesand compare examples text Since come installations next month should keep part handy another look time Also some illus trations coming up Section B can viewed standpoint text well Speaving next month youll find Part 6 loaded detailed information other things needed make installation completeswitches connectors fuses wir ing etc After well discuss planes flying previous parts will come together fairly extensive tabulation known performers complete statisti cal performance information 154 Model Aviation plan wrap up sorts most-often-asked questions will reviewed Also some incidentals oversights throughout will included may wondering Spectra construction article still planned conclusion series Its just end near once perceived Please forward questions SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 realize have times past should have responded bit faster apologize However continue resolute intent answer expedient fashion conditions permitting FF Duration/Meuser Continued paoe 61 models sorts parts accessories miscellaneous goodies small rubberpower CO-2 power models has just troduced new line molded plastic wheels Molded mind vacuumformed As result detail crystalclear neatly-reinforced builtin hub Three sizes currently available hope therell 3/4 diameters weighing respectively 04 06 07 grams price 99tt pack eight size Actually wheel sort halfwheel flip side concave used as-is look pretty good Scale buffs will quick realize look lot realistic two wheels glued together back-to-back way come out rather fat-looking just right some applications prefer thinner look just scrub wheel around piece 80-grit garnet paper few sec onds before gluing halves together dont like looks six-spoke hub glue paper disc pattern preference local dealer doesnt carry tell him Meuser says hes shmoe order direct Peck send $150 Pecks larger-than-ever catalog address PO Box 2498 -La Mesa CA 92041 As sort gentle hint theyd like business catalog comes free first order word wise - Miter boxes revisited Ive published sev eral methods cutting gussets using special home-brew jigs Nat Comfort expressed amusement seeing modelers make such elaborate efforts perform such simple operation points out modelers already own razor saw small miter boxes available X-Acto FAI Model Supply others Using balsa stripstock appropriate size flip-cutflip-cut sequence can up ears gussets watching evening news So whats fuss Well building Half-A larger model using medium-to-hard balsa saw will cut neatly gumming NEW death content equal-leg gus sets what Nat says absolutely true Since description must cover least 90% Free Flight models apologize reminding about humble razor saw off-the-shelf miter box smaller gussetsand especially soft balsathe use single-edge razor blade appropriate razor saw some home-brew miter boxeswhich what arecome play Also scheme showed cutting unequal-leg gussets de sired proportions Nordic Glider trailing edges example undercambered ribs tend mite weak unequal-leg gussets have slight advantage long leg glued side rib Bob Meuser 4200 Gregory St Oakland CA 94619 FF Indoor/Tenny Continued page 62 Testing methods best-doc umented tests model rubber de veloped Fred Pearce test consisted stretching loop rubber about eight times normal length holding extension three minutes recording exten sion loop relaxed few inches time tension measured relaxation interval 5 example length rubber will have carefully measured its weight recorded pounds force tension has re corded relaxation interval force readings summed Fred Wakefield flier Dennis Jaecks decided refine method door Dennis describes testing way I Stretch test loop rubber until tension equals force Fl Fl computed formula Fl rubber weight grams loop length inches 2 3 Record loop length LI force Fl Stretch loop again force F2 F2 430 X rubber wt gin Ll 4 Record loop length L2 force F2 5 Relax loop 3 record force F3 6 Continue relax stretch 3 record force 7 Calculate energy stored sum ming following series F2F3 . 2 2 FnlFn 2 Finally compute energy storage E ft-lb/lb using F t x 16 x force summation Continued page 158 L- C Jee3 what dri Jrni 5f January 1984 155
Edition: Model Aviation - 1984/01
Page Numbers: 60, 61, 154, 155
Free Flight DURA TION Bob Meuser STRANGE configuration saw photo wind-tunnel model similar shown sketch being tested Langley Re search Center Thinking might have some conceivable relation Free Flight model ing checked out chief technical consultant W Hewitt Phillips As configuration originally envi sioned Julian Walkowitz engineer Wright Patterson AFB wing tail joined tips high-aspect-ratio surfaces idea wing tail would brace other giving stiffer structure hence higher flutter speed However stiffness increase nearly great its truss-like front-view appear ance would lead believe Raise nose bit whole thing suddenly becomes lot thinner idea applied somewhat modified form Burt Rutan proposed agricultural aircraft looking somewhat like sketch wind-tunnel tests done primarily obtain stability data rather lift-drag data seems obvious induced drag would less monoplane same span because biplane effect Marginal longitudinal stability required re ducing sweep horizontal tail outboard end tail attached wing means pod extending behind wing Directional stability suf fered because tunnel effect wing-tail combination airflow acting fin putting some fin area above point horizontal tail attaches would cure Hewitt thinks idea worth some experimentationPennyplane perhaps will replace long-tail-boom conventional configuration com petition Free Flight applications Hot engines Nat Comfort Richmond VA suggests Free Flighters might well pay attention Control Line Com bat lads Nats engine started out life OS 25 FSR ABC RC persuasion reworked Combat-style Dick Tyndall well known Eastern Com bat circles Aside obvious custom venturi remote needle valve mount Champs second place Nats little things done engines Tyndall does business under name innards powered Nats Shocer first Virginia Craftsman 348 Argyll Circle place Eastern US Free Flight Highland Springs VA 23075 60 Model Aviation wouldnt want competition Free Flighters miss out good thing though Product Review item July 1983 issue page 56 again Thomas Kosters digital OT timer Since one-function device useful Towline Gliders complete system appears above start switch activated towline release timer Ni-Cd battery pack Below have good look timer itself Note time-set rotary switches settable 6-sec intervals 6 sec 9 mm 54 sec Three holes between switches charging plug Wire swing-arm released solenoid column Competition FF models win better HOT engines Nat Comtorts O as custom jeajures tuning suitable CL Combat Virginia Craftsman won Nets column Koster does again Several years back Thomas Koster three-time World Champ Free Flight events perfected marketed rather expensive digital multi-function timer FAT Power models recently introduced much less expensive singlefunction timer Nordic Towline Gliders See photo timing de thermalizer function accomplished ro tating pair tiny waterproof switches Time can set steps 6 sec zero 9 mm 54 sec accurate 001 percent single arm held latch released actuation sole noid no possibility putting arm wrong notch scroll because isnt scroll unit powered Ni-Cd battery can trickle-charged between flights wait Thats super-cautious Koster claims battery will last 100 actuations between charges Weights timer 18 grams battery 17 grams Prices timer battery start switch $55 trickle charger $30 Source Koster Digital PO Box 54 DK-3400 Hill erod Denmark Towline release photo shows simple type towline release mechanism usable wherever twang-hook might otherwise used comes us Bob Lieber way Doe Jackson little bent wire part per manently attached towhook mechan ism aircraft normally used secure buttons commercial garments such lab coats wire loop attached end towline diameter wire determines tension wire loop disengages button retainer mechanism button retainer attached could simple swinging arm During tow arm would pulled forward line between arm rudder horn would pull rudder straight towline tension re leased rubberband spring oppo site rudder horn would pull rudder circle-tow position separate pull-pin tached short string end towline would set glide position rudder start DT timer New wheels Peck-Polymers famous world wide its Peanut Scale kits plans Hannan others sorts fun-type Continued page 154 January 1984 61 Would believe bench-test setup tricky Towline Glider towhook Wire loop attaches end towline pulls free commercial metal Clip attached model Thickness wire loop determines ten slon line release Peck-Polymers has some molded-plastic wheels rubber models light light light TIGER TAIL 4 Ron Chidgeys latest A best series little larger lighter slower retains honest flight character tistics its predecessors Especially recommended sportsman ad vanced pattern also good choice tor turn-around pattern Plans construction hints -$995 WELLER 3 BLADE PROP very stiff molded fiberglas propellor trom England Its efficient design allows substantial reduction noise level actually improving per formance $2000 NEW CLAMP IT FOREVER STAINLESS STEEL PIPE CLAMPS Light strong Low-profile seiflocking 3116 width wont cut silicone couplers Pkg 4 clamps -$295 flights Persuader weights 33 oz cobalt 05 motor six 12 Ah cells three servos Receivers generally weigh between 1 2 oz some planes remove plastic case save about neaky overweight item flight pack can wiring harness Some surprisingly heavy large switches complete bulky plastic covers lots wire Try some thing lighter Radio installation Electrics relatively easy since minimal vibration usually light mechanical loads Ive elimi nated foam packing am getting away servo rails trays smaller planes double-sticky foam servo mounting tape double sticky Velcro Radio Shack holds servos receiver flight battery attaching double stickies balsa first coat balsa model airplane cement such Ambroid let dry fill wood make sound surface sticky stick case servos stock fuselage sides opposite other put light balsa foam block between keep servos presssed sides prevent rocking pushrod loads feel comfortable con ventional servo-mounting techniques sug gest making servo tray out /v-in Lite Ply using tray sort horizon tal fuselage former during assembly does wonders alignment like Golden Rod small balsa pushrods planes 3/i sq firm balsa rods work very well bind end heavy thread drill #50 hole end center Thread hole 2-56 tap put CyA threads Retap standard pushrod fittings can screwed inadjustable too least weight maximize use pushrod mate rial minimize length metal fitNEW NEW WING TUBE & SOCKETS 1 dia aluminum alloy tubing plug wings Included pair special slip-fit phenolic sockets build wing-structure 2024 alum tube 24 long socket 12 long S8951se1 / - Sleeve Puller -$795 Bearing Puller -$695 ENGINE SLEEVE & BEARING PULLER Pull tight sleeves bearings easily damage Cone cone expanding brass ring grips sleeve bearing ID new 60s 17MM rear bearing *Special* Both $1395 See Dealer Order Direct Include 75 Per Item f UPS Gator RIC Products Pompano Dr G3713 P ensacolaFL 32514 Phone AC t904 476-8639 tings end suggest think terms quarter ounces Four make up ounce four make up quarter-pounder 4 Installation weight purpose following information give some preliminary guidelines examples elec tric power system weight Part 7 well look finished plane weight size power flight times As general rule thumb weight power system motor battery wiring switch prop typical RC Electric about 50% total_place weightwith range limits usually between 40% 60% radio plane make up rest total Table shows some examples As further guideline electricpowered gliders generally have wing load ings 10-11 oz/sq ft aerobatics ships range 12-22 sport Scale about 12-14 Well look particulars future section cant wait can work backwards estimate wing area examples Table 1 5 Look pictures sketchesand compare examples text Since come installations next month should keep part handy another look time Also some illus trations coming up Section B can viewed standpoint text well Speaving next month youll find Part 6 loaded detailed information other things needed make installation completeswitches connectors fuses wir ing etc After well discuss planes flying previous parts will come together fairly extensive tabulation known performers complete statisti cal performance information 154 Model Aviation plan wrap up sorts most-often-asked questions will reviewed Also some incidentals oversights throughout will included may wondering Spectra construction article still planned conclusion series Its just end near once perceived Please forward questions SASE author Bob Kopski 25 West End Dr Lansdale PA 19446 realize have times past should have responded bit faster apologize However continue resolute intent answer expedient fashion conditions permitting FF Duration/Meuser Continued paoe 61 models sorts parts accessories miscellaneous goodies small rubberpower CO-2 power models has just troduced new line molded plastic wheels Molded mind vacuumformed As result detail crystalclear neatly-reinforced builtin hub Three sizes currently available hope therell 3/4 diameters weighing respectively 04 06 07 grams price 99tt pack eight size Actually wheel sort halfwheel flip side concave used as-is look pretty good Scale buffs will quick realize look lot realistic two wheels glued together back-to-back way come out rather fat-looking just right some applications prefer thinner look just scrub wheel around piece 80-grit garnet paper few sec onds before gluing halves together dont like looks six-spoke hub glue paper disc pattern preference local dealer doesnt carry tell him Meuser says hes shmoe order direct Peck send $150 Pecks larger-than-ever catalog address PO Box 2498 -La Mesa CA 92041 As sort gentle hint theyd like business catalog comes free first order word wise - Miter boxes revisited Ive published sev eral methods cutting gussets using special home-brew jigs Nat Comfort expressed amusement seeing modelers make such elaborate efforts perform such simple operation points out modelers already own razor saw small miter boxes available X-Acto FAI Model Supply others Using balsa stripstock appropriate size flip-cutflip-cut sequence can up ears gussets watching evening news So whats fuss Well building Half-A larger model using medium-to-hard balsa saw will cut neatly gumming NEW death content equal-leg gus sets what Nat says absolutely true Since description must cover least 90% Free Flight models apologize reminding about humble razor saw off-the-shelf miter box smaller gussetsand especially soft balsathe use single-edge razor blade appropriate razor saw some home-brew miter boxeswhich what arecome play Also scheme showed cutting unequal-leg gussets de sired proportions Nordic Glider trailing edges example undercambered ribs tend mite weak unequal-leg gussets have slight advantage long leg glued side rib Bob Meuser 4200 Gregory St Oakland CA 94619 FF Indoor/Tenny Continued page 62 Testing methods best-doc umented tests model rubber de veloped Fred Pearce test consisted stretching loop rubber about eight times normal length holding extension three minutes recording exten sion loop relaxed few inches time tension measured relaxation interval 5 example length rubber will have carefully measured its weight recorded pounds force tension has re corded relaxation interval force readings summed Fred Wakefield flier Dennis Jaecks decided refine method door Dennis describes testing way I Stretch test loop rubber until tension equals force Fl Fl computed formula Fl rubber weight grams loop length inches 2 3 Record loop length LI force Fl Stretch loop again force F2 F2 430 X rubber wt gin Ll 4 Record loop length L2 force F2 5 Relax loop 3 record force F3 6 Continue relax stretch 3 record force 7 Calculate energy stored sum ming following series F2F3 . 2 2 FnlFn 2 Finally compute energy storage E ft-lb/lb using F t x 16 x force summation Continued page 158 L- C Jee3 what dri Jrni 5f January 1984 155