Sport-Aerobalics ONE TOPIC has everyone buzzing lately potential loss 27-MHz frequencies radio-controlled model use action proposed FCC Docket #20 120 proposal includes revisions current operating rules would change separate C D classes class effect would preclude radiocontrolled model aircraft flying 27-MHz band because Citizens Band voice operation would permitted five currently exclusive 27-MHz band Class C channels have enough inter ference already 27-MHz exclu sive use five frequencies can imagine bad things would voice transmissions allowed fre quencies hope heard about proposed FCC rule revision time write Congressman Senators June 9th deadline replying FCC us operate 72- 75MHz band shouldnt feel too cozy either rule revision goes through 27MHz fliers can expected join us 72- 75-MHz band make just much difficult have chance fly addition seven 72- 75-MHz band frequencies us have assuming exclusively allocated radio control use actually shared industrial certain municipal users often have very high-power transmitters relative less watt power output us sur prised discover sharing frequencies exclusive band since FCC went far designate four frequencies model aircraft use three shared use among air planes boats cars im plied no other uses permitted case stations licensed op erate 72- 75-MHz frequen cies suspect may some near local FCC office will able help identifying operating frequency power output located near military installation will probably frequency management office will have same informa tion FCC might very useful place couple telephone calls continued page 85 Ace Whizzard authors entry unusual event described column Note use Molds Inc clamps hold sides place As might imagined frontal fiat-plate area flying out house built John Fields needs bit power can squeezed out its Veco 61 RC powerplant August1976 17 Charles Nelsons magnificent Curtiss Jenny loan EAA Museum will flown Nats Photo Lee Fray Sport Aviation Assoc USAF Capts Charlie Blair shown MH Sanders built OS 40-powered canard graduate school research project Called Zonker has balsa fuse foam surfaces weight 5-1/2 lbs RC Sport/Van Putte continued page 17 worst would learn what potentially dangerous frequencies best youd discover no problems Discussions involving effects wind aircraft continue unabated latest package RC-oriented newsletters AMA forwarded con tained copy newsletter South African Assoc Radio Flyers Johannesburg South Africa news letter has section called Opinions Views has apparently used conduct running discussion battle subject effects wind air craft author latest con frontations Len Salter has offered re ward RlOO whatever anyone can prove him aircraft can tell steady wind blowing re cent article classic wish could repeated far too long Let include few short excerpts will give impression article intensity discussion have probably heard said aircraft has better rate climb windnonsense aircraft rolls better downwind upwindnonsense dont believe prove yourself Let us take three rolls normal throttle setting full aileron setting gives three rolls five seconds down wind same throttle setting upwind will still complete five seconds will appear com pressed because have covered far less ground upwind downwind have probably heard clas sic stall turn has fluffed wind blew onto its back could pull out dive time because going downwind Mother age-old classic 1800 turn downwind wind model always balloons does because made balloon newsletter have ex cerpted preceeding contained no less seven pages assertions counter assertions two authors subject wind effects aircraft author sisted other come senses admit errors hobby lot controversial outsiders could possibly imagine way would glad provide copies articles would send stamped self-addressed en velope Let change subject suggesting another RC racing event might saying last thing need another racing event thought Dave Lane Pylon racing contributing editor However Northwest Florida have started racing event associated sport flying Pylon racing started because un see nats flats flats nats 0 C 0 0 RS SYSTEMS 0 AT THE NATS 0 C 0 During years Nats RS Systems will maintain Special Sales Service Headquarters Fairborn IHobby Center Fairborn Ohio service facility will staffed C factory technicians equipped test service instruments repair parts provide full maintenance service capability Also Fairborn Hobby Center will offer complete selection RS Systems 0 accessories sale youre RS owner bring set checkup youre 0 stop examine RS quality 0 4-70 0 C 0WRING ,, -FIELD 7.AIRPORT ALi 0cr At/ : theCENTER NATS 0 RS Systems _________ 0 Fairbom Hobby Center Fairborn Plaza Shopping Center 0 0 to1258 North Broad Street Fairborn OhIo 45324 0 canada RS Systems Canada 2050 MansfIeld St Montreal Quebec H3A 1Y9 Canada 0 0 0 sieu eqi te noA aes aip w noA eas aq w noA aes eqi w nbA aes usual configuration Eglin AFB fly ing site fly inactive field Eglin AFB field has three runways form large triangle distance around triangle approximately 17 miles Just imagine team race several times around triangle pilots flew back pickup truck convertible An obvious problem would arise air planes could outrun vehicles carrying pilots decided limit speed airplanes establishing gentle mens competition ground rules follows Ace constant-chord wingsunmodi fied except addition ailerons ID CR 0 C ID 7 ID 0 i 0 C 0 7 0 0 ID ID 0 C 0 7 ID DI ID ID 0 C 0 7 ID 0 ID ID 0 C 0 7 0 0 ID ID 0 C ID 7 ID 0 ID ID 0 C 0 7 ID 0 2 Cox Baby Bee 049 engine 3 No auxiliary fuel tank just what engine 4 Fuel no greater 15% nitro methane 5 Conventional landing gear stand ard 1 wheels 6 6-3 nylon wood prop surprisingly object first complete certain number laps around race course However races will long enough several pit stops required look forward lot fun summer competing low pressure racing event Its obvious kind racing August1976 85 intend totally inappropriate flying sites around country flying fields could have competitions similar could use et racing course stand place instead flying vehicle pit crew would get lot exercise airplane ran out fuel other end course might like give try because although formulated keep race speeds down rules will cause cost airplane relatively low Besides just might have great time As being written Im preparing attend first pattern contest 1976 Practicing new Advanced pattern has caused few changes initial atti tudes toward several maneuvers first place two-point roll easy first thought After practicing both maneuvers now believe four-point roll easier two-point roll Other observations can per form spins reliably now slow roll much easier feared main reason installed two dual rate switches transmitter couple weeks ago transmitter now has dual rates elevator aileron low rate elevator normal flying high rate position gives elevator doing spins high rate aileron normal flying low rate position gives just right amount aileron slow roll Now have worry about putting right amount elevator rudder control easy install both dual rate sys tems following instructions Jim Oddino included column November 1975 issue Radio Control Modeler magazine purchased two toggle switches identical retract switch transmitter obtained two sets trim pots Ace R/C Catalog numbers 29K 14 10K 29K38 47K total price installing two dual rate switches came less $8 worked since Im no electronic expert should work maybe can con club electronic wizard doing you interested concept would like hear about write Model Aviations Radio Tech nique contributing editor George Myers encourage him write future col umn about Let close humorous contribu tion Paul Harvey used Paul Harvey News April 9 1976 Telephone call Gary Fuller home Juneau Alaska answered Fullers daughter age six caller asked daddy home said Daddy out flying caller asked will home said until runs out gas crashes hung up. explaining daddy flies radio controlled miniature air craft caller still shock address 12 Connie Dr Shalimar FL 32579 CL Navy Carrier/Perry continued page 30 produce minimum drag relatively high lift coefficients around 05 example compared low lift coeffi cients less 01 needed typical Carrier model high speed Designing low speed would mean using airfoil 15% 18% thickness flaps used Flaps can used increase available lift coefficients keeping camber low during high speed flight speeds sizes used Carrier flaps bene ficial very thick airfoils 20% greater flaps cant used best advan tage increasing drag high speeds An airfoil flaps will however provide greater lift drag under same conditions same airfoil out flaps will discuss flaps detail next column idea best compromise Carrier airfoil consists about 10% 12% thickness camber about 1% airfoil can operate near its minimumdrag lift coefficient high speed yet has some camber enough thickness provide reasonable lift coefficients low speeds airfoil also thick enough built light benefit use flaps Using four-digit designation system developed NACA forerunner NASA NACA 1310 airfoil fits requirements airfoil 1% camber first digit 10% thickness last two digits second digit indicates point maximum camberin case 30% should 3 4 model applica tions An airfoil such NACA 6315 would provide good low speed perfor mance flaps NACA 0006 symmetrical 6% thickness would optimum Profile airplane designed emphasize high speed An airfoil built NACA coordinates about best can given camber thickness airfoil reasonable shape will come close NACA airfoils efficiency Three things im portant airfoil surfaces must free abrupt changes contour point maximum thickness should around 30% chord leading edge should rounded last point important sharp leading edge useful supersonic speeds speeds about will reduce maximum lift coefficient cause increased drag high speed flight lift coefficient outside very narrow range source NACA airfoils read next section Products Services Whenever find out about new services sources equip ment interest Carrier modelers will pass information column am trying sell products services just want keep Carrier modelers aware sources available us receive products evaluation will give complete description results tests make will make claims product unless have per sonally checked opinions will own will include addresses can write include stamped envelope information availability prices received couple letters samples after column pressure fuel systems Carrier William Moose Allen 418 Fairmont DeKaIb IL 60115 offers good bladder very reasonable price 20 plus postage George Mattei G-T-M Products 105 Franklin Rd HamdenCT 06517 offers bladders pacifiers fuel syringes other specialty items George sent along sam ple 8-oz fuel bulb sells bulb have used can handle pressure required fill bladder out leaking blowing apart stood full bulb could get leak capacity allows one-shot filling with86 Model Aviation RC Sport continued
Edition: Model Aviation - 1976/08
Page Numbers: 17, 85, 86
Sport-Aerobalics ONE TOPIC has everyone buzzing lately potential loss 27-MHz frequencies radio-controlled model use action proposed FCC Docket #20 120 proposal includes revisions current operating rules would change separate C D classes class effect would preclude radiocontrolled model aircraft flying 27-MHz band because Citizens Band voice operation would permitted five currently exclusive 27-MHz band Class C channels have enough inter ference already 27-MHz exclu sive use five frequencies can imagine bad things would voice transmissions allowed fre quencies hope heard about proposed FCC rule revision time write Congressman Senators June 9th deadline replying FCC us operate 72- 75MHz band shouldnt feel too cozy either rule revision goes through 27MHz fliers can expected join us 72- 75-MHz band make just much difficult have chance fly addition seven 72- 75-MHz band frequencies us have assuming exclusively allocated radio control use actually shared industrial certain municipal users often have very high-power transmitters relative less watt power output us sur prised discover sharing frequencies exclusive band since FCC went far designate four frequencies model aircraft use three shared use among air planes boats cars im plied no other uses permitted case stations licensed op erate 72- 75-MHz frequen cies suspect may some near local FCC office will able help identifying operating frequency power output located near military installation will probably frequency management office will have same informa tion FCC might very useful place couple telephone calls continued page 85 Ace Whizzard authors entry unusual event described column Note use Molds Inc clamps hold sides place As might imagined frontal fiat-plate area flying out house built John Fields needs bit power can squeezed out its Veco 61 RC powerplant August1976 17 Charles Nelsons magnificent Curtiss Jenny loan EAA Museum will flown Nats Photo Lee Fray Sport Aviation Assoc USAF Capts Charlie Blair shown MH Sanders built OS 40-powered canard graduate school research project Called Zonker has balsa fuse foam surfaces weight 5-1/2 lbs RC Sport/Van Putte continued page 17 worst would learn what potentially dangerous frequencies best youd discover no problems Discussions involving effects wind aircraft continue unabated latest package RC-oriented newsletters AMA forwarded con tained copy newsletter South African Assoc Radio Flyers Johannesburg South Africa news letter has section called Opinions Views has apparently used conduct running discussion battle subject effects wind air craft author latest con frontations Len Salter has offered re ward RlOO whatever anyone can prove him aircraft can tell steady wind blowing re cent article classic wish could repeated far too long Let include few short excerpts will give impression article intensity discussion have probably heard said aircraft has better rate climb windnonsense aircraft rolls better downwind upwindnonsense dont believe prove yourself Let us take three rolls normal throttle setting full aileron setting gives three rolls five seconds down wind same throttle setting upwind will still complete five seconds will appear com pressed because have covered far less ground upwind downwind have probably heard clas sic stall turn has fluffed wind blew onto its back could pull out dive time because going downwind Mother age-old classic 1800 turn downwind wind model always balloons does because made balloon newsletter have ex cerpted preceeding contained no less seven pages assertions counter assertions two authors subject wind effects aircraft author sisted other come senses admit errors hobby lot controversial outsiders could possibly imagine way would glad provide copies articles would send stamped self-addressed en velope Let change subject suggesting another RC racing event might saying last thing need another racing event thought Dave Lane Pylon racing contributing editor However Northwest Florida have started racing event associated sport flying Pylon racing started because un see nats flats flats nats 0 C 0 0 RS SYSTEMS 0 AT THE NATS 0 C 0 During years Nats RS Systems will maintain Special Sales Service Headquarters Fairborn IHobby Center Fairborn Ohio service facility will staffed C factory technicians equipped test service instruments repair parts provide full maintenance service capability Also Fairborn Hobby Center will offer complete selection RS Systems 0 accessories sale youre RS owner bring set checkup youre 0 stop examine RS quality 0 4-70 0 C 0WRING ,, -FIELD 7.AIRPORT ALi 0cr At/ : theCENTER NATS 0 RS Systems _________ 0 Fairbom Hobby Center Fairborn Plaza Shopping Center 0 0 to1258 North Broad Street Fairborn OhIo 45324 0 canada RS Systems Canada 2050 MansfIeld St Montreal Quebec H3A 1Y9 Canada 0 0 0 sieu eqi te noA aes aip w noA eas aq w noA aes eqi w nbA aes usual configuration Eglin AFB fly ing site fly inactive field Eglin AFB field has three runways form large triangle distance around triangle approximately 17 miles Just imagine team race several times around triangle pilots flew back pickup truck convertible An obvious problem would arise air planes could outrun vehicles carrying pilots decided limit speed airplanes establishing gentle mens competition ground rules follows Ace constant-chord wingsunmodi fied except addition ailerons ID CR 0 C ID 7 ID 0 i 0 C 0 7 0 0 ID ID 0 C 0 7 ID DI ID ID 0 C 0 7 ID 0 ID ID 0 C 0 7 0 0 ID ID 0 C ID 7 ID 0 ID ID 0 C 0 7 ID 0 2 Cox Baby Bee 049 engine 3 No auxiliary fuel tank just what engine 4 Fuel no greater 15% nitro methane 5 Conventional landing gear stand ard 1 wheels 6 6-3 nylon wood prop surprisingly object first complete certain number laps around race course However races will long enough several pit stops required look forward lot fun summer competing low pressure racing event Its obvious kind racing August1976 85 intend totally inappropriate flying sites around country flying fields could have competitions similar could use et racing course stand place instead flying vehicle pit crew would get lot exercise airplane ran out fuel other end course might like give try because although formulated keep race speeds down rules will cause cost airplane relatively low Besides just might have great time As being written Im preparing attend first pattern contest 1976 Practicing new Advanced pattern has caused few changes initial atti tudes toward several maneuvers first place two-point roll easy first thought After practicing both maneuvers now believe four-point roll easier two-point roll Other observations can per form spins reliably now slow roll much easier feared main reason installed two dual rate switches transmitter couple weeks ago transmitter now has dual rates elevator aileron low rate elevator normal flying high rate position gives elevator doing spins high rate aileron normal flying low rate position gives just right amount aileron slow roll Now have worry about putting right amount elevator rudder control easy install both dual rate sys tems following instructions Jim Oddino included column November 1975 issue Radio Control Modeler magazine purchased two toggle switches identical retract switch transmitter obtained two sets trim pots Ace R/C Catalog numbers 29K 14 10K 29K38 47K total price installing two dual rate switches came less $8 worked since Im no electronic expert should work maybe can con club electronic wizard doing you interested concept would like hear about write Model Aviations Radio Tech nique contributing editor George Myers encourage him write future col umn about Let close humorous contribu tion Paul Harvey used Paul Harvey News April 9 1976 Telephone call Gary Fuller home Juneau Alaska answered Fullers daughter age six caller asked daddy home said Daddy out flying caller asked will home said until runs out gas crashes hung up. explaining daddy flies radio controlled miniature air craft caller still shock address 12 Connie Dr Shalimar FL 32579 CL Navy Carrier/Perry continued page 30 produce minimum drag relatively high lift coefficients around 05 example compared low lift coeffi cients less 01 needed typical Carrier model high speed Designing low speed would mean using airfoil 15% 18% thickness flaps used Flaps can used increase available lift coefficients keeping camber low during high speed flight speeds sizes used Carrier flaps bene ficial very thick airfoils 20% greater flaps cant used best advan tage increasing drag high speeds An airfoil flaps will however provide greater lift drag under same conditions same airfoil out flaps will discuss flaps detail next column idea best compromise Carrier airfoil consists about 10% 12% thickness camber about 1% airfoil can operate near its minimumdrag lift coefficient high speed yet has some camber enough thickness provide reasonable lift coefficients low speeds airfoil also thick enough built light benefit use flaps Using four-digit designation system developed NACA forerunner NASA NACA 1310 airfoil fits requirements airfoil 1% camber first digit 10% thickness last two digits second digit indicates point maximum camberin case 30% should 3 4 model applica tions An airfoil such NACA 6315 would provide good low speed perfor mance flaps NACA 0006 symmetrical 6% thickness would optimum Profile airplane designed emphasize high speed An airfoil built NACA coordinates about best can given camber thickness airfoil reasonable shape will come close NACA airfoils efficiency Three things im portant airfoil surfaces must free abrupt changes contour point maximum thickness should around 30% chord leading edge should rounded last point important sharp leading edge useful supersonic speeds speeds about will reduce maximum lift coefficient cause increased drag high speed flight lift coefficient outside very narrow range source NACA airfoils read next section Products Services Whenever find out about new services sources equip ment interest Carrier modelers will pass information column am trying sell products services just want keep Carrier modelers aware sources available us receive products evaluation will give complete description results tests make will make claims product unless have per sonally checked opinions will own will include addresses can write include stamped envelope information availability prices received couple letters samples after column pressure fuel systems Carrier William Moose Allen 418 Fairmont DeKaIb IL 60115 offers good bladder very reasonable price 20 plus postage George Mattei G-T-M Products 105 Franklin Rd HamdenCT 06517 offers bladders pacifiers fuel syringes other specialty items George sent along sam ple 8-oz fuel bulb sells bulb have used can handle pressure required fill bladder out leaking blowing apart stood full bulb could get leak capacity allows one-shot filling with86 Model Aviation RC Sport continued
Edition: Model Aviation - 1976/08
Page Numbers: 17, 85, 86
Sport-Aerobalics ONE TOPIC has everyone buzzing lately potential loss 27-MHz frequencies radio-controlled model use action proposed FCC Docket #20 120 proposal includes revisions current operating rules would change separate C D classes class effect would preclude radiocontrolled model aircraft flying 27-MHz band because Citizens Band voice operation would permitted five currently exclusive 27-MHz band Class C channels have enough inter ference already 27-MHz exclu sive use five frequencies can imagine bad things would voice transmissions allowed fre quencies hope heard about proposed FCC rule revision time write Congressman Senators June 9th deadline replying FCC us operate 72- 75MHz band shouldnt feel too cozy either rule revision goes through 27MHz fliers can expected join us 72- 75-MHz band make just much difficult have chance fly addition seven 72- 75-MHz band frequencies us have assuming exclusively allocated radio control use actually shared industrial certain municipal users often have very high-power transmitters relative less watt power output us sur prised discover sharing frequencies exclusive band since FCC went far designate four frequencies model aircraft use three shared use among air planes boats cars im plied no other uses permitted case stations licensed op erate 72- 75-MHz frequen cies suspect may some near local FCC office will able help identifying operating frequency power output located near military installation will probably frequency management office will have same informa tion FCC might very useful place couple telephone calls continued page 85 Ace Whizzard authors entry unusual event described column Note use Molds Inc clamps hold sides place As might imagined frontal fiat-plate area flying out house built John Fields needs bit power can squeezed out its Veco 61 RC powerplant August1976 17 Charles Nelsons magnificent Curtiss Jenny loan EAA Museum will flown Nats Photo Lee Fray Sport Aviation Assoc USAF Capts Charlie Blair shown MH Sanders built OS 40-powered canard graduate school research project Called Zonker has balsa fuse foam surfaces weight 5-1/2 lbs RC Sport/Van Putte continued page 17 worst would learn what potentially dangerous frequencies best youd discover no problems Discussions involving effects wind aircraft continue unabated latest package RC-oriented newsletters AMA forwarded con tained copy newsletter South African Assoc Radio Flyers Johannesburg South Africa news letter has section called Opinions Views has apparently used conduct running discussion battle subject effects wind air craft author latest con frontations Len Salter has offered re ward RlOO whatever anyone can prove him aircraft can tell steady wind blowing re cent article classic wish could repeated far too long Let include few short excerpts will give impression article intensity discussion have probably heard said aircraft has better rate climb windnonsense aircraft rolls better downwind upwindnonsense dont believe prove yourself Let us take three rolls normal throttle setting full aileron setting gives three rolls five seconds down wind same throttle setting upwind will still complete five seconds will appear com pressed because have covered far less ground upwind downwind have probably heard clas sic stall turn has fluffed wind blew onto its back could pull out dive time because going downwind Mother age-old classic 1800 turn downwind wind model always balloons does because made balloon newsletter have ex cerpted preceeding contained no less seven pages assertions counter assertions two authors subject wind effects aircraft author sisted other come senses admit errors hobby lot controversial outsiders could possibly imagine way would glad provide copies articles would send stamped self-addressed en velope Let change subject suggesting another RC racing event might saying last thing need another racing event thought Dave Lane Pylon racing contributing editor However Northwest Florida have started racing event associated sport flying Pylon racing started because un see nats flats flats nats 0 C 0 0 RS SYSTEMS 0 AT THE NATS 0 C 0 During years Nats RS Systems will maintain Special Sales Service Headquarters Fairborn IHobby Center Fairborn Ohio service facility will staffed C factory technicians equipped test service instruments repair parts provide full maintenance service capability Also Fairborn Hobby Center will offer complete selection RS Systems 0 accessories sale youre RS owner bring set checkup youre 0 stop examine RS quality 0 4-70 0 C 0WRING ,, -FIELD 7.AIRPORT ALi 0cr At/ : theCENTER NATS 0 RS Systems _________ 0 Fairbom Hobby Center Fairborn Plaza Shopping Center 0 0 to1258 North Broad Street Fairborn OhIo 45324 0 canada RS Systems Canada 2050 MansfIeld St Montreal Quebec H3A 1Y9 Canada 0 0 0 sieu eqi te noA aes aip w noA eas aq w noA aes eqi w nbA aes usual configuration Eglin AFB fly ing site fly inactive field Eglin AFB field has three runways form large triangle distance around triangle approximately 17 miles Just imagine team race several times around triangle pilots flew back pickup truck convertible An obvious problem would arise air planes could outrun vehicles carrying pilots decided limit speed airplanes establishing gentle mens competition ground rules follows Ace constant-chord wingsunmodi fied except addition ailerons ID CR 0 C ID 7 ID 0 i 0 C 0 7 0 0 ID ID 0 C 0 7 ID DI ID ID 0 C 0 7 ID 0 ID ID 0 C 0 7 0 0 ID ID 0 C ID 7 ID 0 ID ID 0 C 0 7 ID 0 2 Cox Baby Bee 049 engine 3 No auxiliary fuel tank just what engine 4 Fuel no greater 15% nitro methane 5 Conventional landing gear stand ard 1 wheels 6 6-3 nylon wood prop surprisingly object first complete certain number laps around race course However races will long enough several pit stops required look forward lot fun summer competing low pressure racing event Its obvious kind racing August1976 85 intend totally inappropriate flying sites around country flying fields could have competitions similar could use et racing course stand place instead flying vehicle pit crew would get lot exercise airplane ran out fuel other end course might like give try because although formulated keep race speeds down rules will cause cost airplane relatively low Besides just might have great time As being written Im preparing attend first pattern contest 1976 Practicing new Advanced pattern has caused few changes initial atti tudes toward several maneuvers first place two-point roll easy first thought After practicing both maneuvers now believe four-point roll easier two-point roll Other observations can per form spins reliably now slow roll much easier feared main reason installed two dual rate switches transmitter couple weeks ago transmitter now has dual rates elevator aileron low rate elevator normal flying high rate position gives elevator doing spins high rate aileron normal flying low rate position gives just right amount aileron slow roll Now have worry about putting right amount elevator rudder control easy install both dual rate sys tems following instructions Jim Oddino included column November 1975 issue Radio Control Modeler magazine purchased two toggle switches identical retract switch transmitter obtained two sets trim pots Ace R/C Catalog numbers 29K 14 10K 29K38 47K total price installing two dual rate switches came less $8 worked since Im no electronic expert should work maybe can con club electronic wizard doing you interested concept would like hear about write Model Aviations Radio Tech nique contributing editor George Myers encourage him write future col umn about Let close humorous contribu tion Paul Harvey used Paul Harvey News April 9 1976 Telephone call Gary Fuller home Juneau Alaska answered Fullers daughter age six caller asked daddy home said Daddy out flying caller asked will home said until runs out gas crashes hung up. explaining daddy flies radio controlled miniature air craft caller still shock address 12 Connie Dr Shalimar FL 32579 CL Navy Carrier/Perry continued page 30 produce minimum drag relatively high lift coefficients around 05 example compared low lift coeffi cients less 01 needed typical Carrier model high speed Designing low speed would mean using airfoil 15% 18% thickness flaps used Flaps can used increase available lift coefficients keeping camber low during high speed flight speeds sizes used Carrier flaps bene ficial very thick airfoils 20% greater flaps cant used best advan tage increasing drag high speeds An airfoil flaps will however provide greater lift drag under same conditions same airfoil out flaps will discuss flaps detail next column idea best compromise Carrier airfoil consists about 10% 12% thickness camber about 1% airfoil can operate near its minimumdrag lift coefficient high speed yet has some camber enough thickness provide reasonable lift coefficients low speeds airfoil also thick enough built light benefit use flaps Using four-digit designation system developed NACA forerunner NASA NACA 1310 airfoil fits requirements airfoil 1% camber first digit 10% thickness last two digits second digit indicates point maximum camberin case 30% should 3 4 model applica tions An airfoil such NACA 6315 would provide good low speed perfor mance flaps NACA 0006 symmetrical 6% thickness would optimum Profile airplane designed emphasize high speed An airfoil built NACA coordinates about best can given camber thickness airfoil reasonable shape will come close NACA airfoils efficiency Three things im portant airfoil surfaces must free abrupt changes contour point maximum thickness should around 30% chord leading edge should rounded last point important sharp leading edge useful supersonic speeds speeds about will reduce maximum lift coefficient cause increased drag high speed flight lift coefficient outside very narrow range source NACA airfoils read next section Products Services Whenever find out about new services sources equip ment interest Carrier modelers will pass information column am trying sell products services just want keep Carrier modelers aware sources available us receive products evaluation will give complete description results tests make will make claims product unless have per sonally checked opinions will own will include addresses can write include stamped envelope information availability prices received couple letters samples after column pressure fuel systems Carrier William Moose Allen 418 Fairmont DeKaIb IL 60115 offers good bladder very reasonable price 20 plus postage George Mattei G-T-M Products 105 Franklin Rd HamdenCT 06517 offers bladders pacifiers fuel syringes other specialty items George sent along sam ple 8-oz fuel bulb sells bulb have used can handle pressure required fill bladder out leaking blowing apart stood full bulb could get leak capacity allows one-shot filling with86 Model Aviation RC Sport continued