BILL WINTERS IONEi1Li3 erodynam icsis sci ence Since days vision aries dreamers going back before Wrights born countless minds have struggled its fundamentals studied wind tunnels laboratories evolved theories laws wartime its refine ment took quantum jumps lifetime have seen aviation advance step re lated sciences metallurgy electronics name just twofrom point new plane proved airworthy until daring test pilot tried out fre quently losing life todays ability project multi-million jumbo jet supersonic fighterwhich sold hundreds before prototype takes shape factory aerodynamic laws im mutable experimenter would seem thing past being nothing unknown discover restless minds continue divine new ways apply laws hand see engineering task forces equipped computers project craft desired characteristics performance capa city 747 other see designer equivalent old test pilot perceives laws outline never-ending areas things filled Convair F-i 02 refused break sound barrier Whitcomb came up coke bottle fuselage theory having cross sectional area its proper location machine whole devised winglet seen Varieze home-built new Learjet No aerodynamic magna charta can begin define infinite ways old laws can applied fornew answers Variations configurations pebbles beach refer normal differences between light plane airliner variations due intended purpose VTO blown wings lifting bodies deltas flying wings /N / C V 4 / nice cloverleaf iext time leave off etem canards circularwings name it exists world full-scale aerodynamics everything comes full circle However bizarre machine works confirms what rules science proscribe knows what other things finding Model aerodynamics cut try cut dried often argue over angels can dance head pin Although bound same laws nature sometimes seems different ballgame will debate until cows come home whether symmetrical airfoil mysteriously lifts zero degrees Fullscale engineers happen ac tive modelers remind us no uncertain terms impossibility Sure impossible but. impossible must provide mite up ship flying upright tad down flying inverted Yet fly things swear controlline stunter like RC pattern job will stay put will fly steadily reasonable time upright inverted once positioned feeding such tiny input arent aware Like horse can led water cannot made drink writer has open mind few dozen other modeling phenomena closed mind Darned know Joe Wagner one-time prominent kit designerthe Dakota biplane left thrust far anyone used before sinceand stated symmetrical airfoil somehow changes its angle ofattackorsomething such high frequency continuously oscillating seek its flyable angle eye cannot perceive Frank Zaic expounded circular air flow thing affects way model circles bankand weve debated least 25 years have heard center-of-lateral area debate still unsettled after good 40 years may never argue anyone pro con en couraged fact grand pappy used blow steam out ears argued about Friends have known talk other years because CIA such thing CLA writer thinks ne has weathercock stability presumed Continued page 72 6 Model Aviation Westchester County Center White Plains New York Dont miss 12th annual show Itll biggest best ever Keep last weekend February open 1980 WRAMs Show going largest yet Well over 150 manufacturers other ex hibiters have already signed up bring everything thats new hobby--- kits engines radi os accessories everything between famous Swap Shop will full operation thousands items including built-up planes almost new radios engines on something just about everyone Westchester County Center centrally located city White Plains N intersection RI 110 Central Park Ace. Oronx Ricer Parkway White Plains lust 22 miles north VC Static Competition Make sure latest creation finished up polished youll have chance take home dozens trophies fered events Ww POST AMI Military POST I/RN NOc-MiIituyI PAtTERN SPORT BIPLANE OLD TIMERS SPORT PYLON GLIDERS HELICOPTERS SCALE RIC BOATS RACING RJC BOATS STAND-OFF SCALE JUNIOR EVENTS RIC CARS REST-IN-SHOW Judging takes place Sunday afternoon Entries accepted until 12Noon Sunday Openers/Winter continued page 6 center its side area lies sufficiently behind CG make tracklike feathers arrow profile weathervane traditional argument CLA too far above CG plane would forced spiral dive banked turned because skidding effect airflow outside circle exerting leverage proportion moment arm between CG CLA came Goldberg Zipper pylon gas model spiraled upward under power shook up hardline tradi tionalists long theory revised account two CLAs froffltthe CG andihetttherbehind line drawn between two would impart nose up SWAP SHOP WRAMs Swap Shop has become malor show attractions thousands individual items changing hands help eliminate registration crush 1980 Swap Shop will have special pre-registra lion line have com pleted pre-registration form receive forms send selfaddressed stamped envelope John Isbister 4 Devon Rd Larchmont NY 10528 SPECIAL NOTE Because increased volume items being brought Swap Shop combined space limita tions built-up model will accepted Swap Shop regis trant further informalion write Lam OiRubbo 16 Lindsey Ace Buchanan NY 10511 914 739-2827 WESTCHESTER RADIO AEROMODELERS INC February 23/21i 10AM 6 PM attitude forward CLA higher rearward inclination line barometer might say emphasis ward profile pattern airplane improve knife-edge example revised theory account Walt Mooneys comic free flights have no dihedral have huge funny pilot profile really fin sticking up cockpit really just same Low-speed aerodynamics never developed remotely compare full-scale knowledge cant make up minds smooth wing rough better fiddle turbulators multispars turbulate airflow over model wing presume keep flow breaking away prematurely top surface airfoiL So sounds contradic tory spanking new little scale model seems improve age patches dinks dents begin appear may fast once appears become flying carpet Reynolds Number mighty factor stern task master world indoor different youll agree fast pattern job RN goes up its best glass-like wings seems true FAI RC sailplanes full-scale world deals well-defined set rulesalthough reality great void between Cub ajet liner far wing efficiency lifting capacity concerned world appears level upon level note majestic flight 1/4 scale design parameters stretched like rubber bands seems tell us comparison full-scale aerody namics laws nature have left us modelers worlds still explore believe know everything know basic rules determine configur ation Consider fact awing must somehow stabilized hold its optimum position flight have ever seen free-flight wing depart model high sky rotate around some spanwise axis know what lack such stabilizing force really means As angle attack loose wing increases first pitch-up know thatthe center pressure lift moves forward airfoil destabilize flat plate like sheet balsa wing CL moves rearward Convex sections reduce distance CL will shift So can wing made stable no stabilizer present incorporate sweepback still have supply further stabilization wing twistex aggerated washout tips providing uptilted surfaces tips same purpose possible through airfoil variations other tricky stuff too devious consider limited space have stable flying plank Without hoopla will agree orthodox wing simply must stabilizing force stabilizer winglike horizontal area taiL Some years ago Mr Norman K Walker gave lecture members DC/RC entitled Stability Control Model Air craft long intriguing lecture presented diagrams variety strange models make points Among strange beastie shown accompanying photo graph Instead conventional stabilizer achieved necessary stability small flat plate mounted front high fin After have figured out will perceive notion ways skinning scat laws aerodynamics may fixed thing however strange confirming end employment model designer eloquently suggests adventures lie future draw precise airfoils yet majority sport models rubber gas radio otThand zip can perform just well better speak downwash angles put stab really knows downwash given model may slow molasses fast enough duplicate homebuilt speeds typical indoor model may weigh gram two rubber Consider wing loading would bet life model has tip vortices air pressure thing tip borders non-existent Would agitate tissue streamer aerodynamics science itmeanders still waters low Reynolds Numbers work some cases Low speed aerodynamics know proves mans educated guess good anothers may Continued page 96 72 Model Aviation assou,c ao,c/TONES EN0AN0 aC es0EOss N rare 55551W 4t 00 ii-0 4 0 0 two classics Flyline COMING SOON 11/2 Scale Farman Moustique READY NOW 47iiCO BO Products BOBCO parts factory parts replacement parts manufactured BOBCO Call Write Complete Information Entire Line DEALER PROGRAMS ENCOURAGED SEE YOUR LOCAL HOBBY DEALER send 25f catalog _____________34 span ower single channel or$1595 free flight OUAKER FLASH FLYLINE MODELS INC 2820 DOAR AVENUE B-Il FAIRFAX VIRGINIA 22031 703 573-2030 BLADES JET RANGER$1295 ALLOUETE$1295 COMMANDER$895 HELIBOY$895 HELIBABY$495 REVOLUTION 1$495 ROTOR SHAFTS HELIBABY$495 COMMANDER$995 REVOLUTION 1$495 FAN SHROUDS 40 60 size$795 Have AMERICAN KAVAN Helicoptors parts DISCOUNT PRICES 10% Discount 5 Sets CA residents add 6% sales tax2504 C-i S Santa Fe Avenue add $150 postage & handlingVista CA 92083 check moncy order toTel 714 727 41304 Openers/Winter continued page 72 forgiven being doubting Thomas Everything completely obvious scrutable Quarter- Scale movement biggies general apparently has encountered its first headache dire predictions having far fallen faces problem did show itself proved electronic Gremlin-like nature does affect such craft perhaps unlucky victim phenomena wont find very funny According memorandum AMA Frequency Committee RC Modelers RC Radio Manufacturers sent Quarter-Scale Association some planes just flat unflyable Noise ancient nemesis caused universal grief some years ago like insects develop immunity pesticides once again major challenge Present radios have dealt problem ordinary airplanes biggies ordinary airplanes know importance avoiding metal-to-metal contacts though modem radios have eliminated great deal such self-generated interference padded circuits noise resistant memo compared approach caging wild tiger some minor problem breaks lock hell can burst loose Large engines can vibrate like buzz saws metal fittings strength occasional ships require spiderweb rigging wires No mention made cable control wires running over place possible interaction between things servo cables antennas possibly wires cables may create other spooky problems though FO quali fied wonder Fortunately QSAA has world-wide experience conclusive evidence FM radios eliminate problem memo urges drive obtain FCC approval FM frequencies will report now matter being pursued AMA FCC receptive granting new FM frequencies RC will reading about AMA section magazine action unfolds editor fully convinced contact quarter-scaler friends problem can acute has unflyable 60-powered job flight disaster spite interchang ing Kraft Futaba systems have file expensive project also manufactured some later date both designer manufacturer ask us run warning note may unflyable manufacturer has post poned full line lovely biggies afraid flight test until answer found Mean takes good old AMA get frequencies AMA s current effort may solve problem Whatever outcome takes oh much timeit encouraging see alert QSAA effective on-the-ball organization getting word out warn others John Prestons column Safety month may important thing have ever read has unpleasant things say about fatal accidents flying CL models near powerlines editor helm ofMANmany years ago record kept fatalities appeared both US British newspapers ten-year period count stood 16 prior 1960 Preston mentions eight over past six years Manufacturers have driven out businessand constant threat radio too other reasonssince todays practice people sue everyone sight manufacturers props wheels parts AMA itself free concern speak ing CL models writer Matty Sullivan once investigated matter power companies New York Philadelphiaboth printed literature combat problem advised Preston says model does actually have touch such lines control lines may metal told electrical current jumps gap will follow direction must try educate everyone far wide please report type model accident Preston guidance column Safety Preston continued page 25 coroners report may step closer having some outside legislation affecting hobby rest us DO NOT FLY NEAR OVERHEAD POWER LINES John Preston 7012 Elsira Ct Falls Church VA 22042 96 Model Aviation Norman Walker demonstration model referred FO the right wont fly efficiently normal model horizontal tail small flat plate ward slanted fin provides drag stabilizes airplane pitch Left Another oddities straight-winged tail-less 1/4 camber airfoil inverted After half out side loop following launching will stabilize fly invertedknew youd curious
Edition: Model Aviation - 1980/02
Page Numbers: 6, 72, 96
BILL WINTERS IONEi1Li3 erodynam icsis sci ence Since days vision aries dreamers going back before Wrights born countless minds have struggled its fundamentals studied wind tunnels laboratories evolved theories laws wartime its refine ment took quantum jumps lifetime have seen aviation advance step re lated sciences metallurgy electronics name just twofrom point new plane proved airworthy until daring test pilot tried out fre quently losing life todays ability project multi-million jumbo jet supersonic fighterwhich sold hundreds before prototype takes shape factory aerodynamic laws im mutable experimenter would seem thing past being nothing unknown discover restless minds continue divine new ways apply laws hand see engineering task forces equipped computers project craft desired characteristics performance capa city 747 other see designer equivalent old test pilot perceives laws outline never-ending areas things filled Convair F-i 02 refused break sound barrier Whitcomb came up coke bottle fuselage theory having cross sectional area its proper location machine whole devised winglet seen Varieze home-built new Learjet No aerodynamic magna charta can begin define infinite ways old laws can applied fornew answers Variations configurations pebbles beach refer normal differences between light plane airliner variations due intended purpose VTO blown wings lifting bodies deltas flying wings /N / C V 4 / nice cloverleaf iext time leave off etem canards circularwings name it exists world full-scale aerodynamics everything comes full circle However bizarre machine works confirms what rules science proscribe knows what other things finding Model aerodynamics cut try cut dried often argue over angels can dance head pin Although bound same laws nature sometimes seems different ballgame will debate until cows come home whether symmetrical airfoil mysteriously lifts zero degrees Fullscale engineers happen ac tive modelers remind us no uncertain terms impossibility Sure impossible but. impossible must provide mite up ship flying upright tad down flying inverted Yet fly things swear controlline stunter like RC pattern job will stay put will fly steadily reasonable time upright inverted once positioned feeding such tiny input arent aware Like horse can led water cannot made drink writer has open mind few dozen other modeling phenomena closed mind Darned know Joe Wagner one-time prominent kit designerthe Dakota biplane left thrust far anyone used before sinceand stated symmetrical airfoil somehow changes its angle ofattackorsomething such high frequency continuously oscillating seek its flyable angle eye cannot perceive Frank Zaic expounded circular air flow thing affects way model circles bankand weve debated least 25 years have heard center-of-lateral area debate still unsettled after good 40 years may never argue anyone pro con en couraged fact grand pappy used blow steam out ears argued about Friends have known talk other years because CIA such thing CLA writer thinks ne has weathercock stability presumed Continued page 72 6 Model Aviation Westchester County Center White Plains New York Dont miss 12th annual show Itll biggest best ever Keep last weekend February open 1980 WRAMs Show going largest yet Well over 150 manufacturers other ex hibiters have already signed up bring everything thats new hobby--- kits engines radi os accessories everything between famous Swap Shop will full operation thousands items including built-up planes almost new radios engines on something just about everyone Westchester County Center centrally located city White Plains N intersection RI 110 Central Park Ace. Oronx Ricer Parkway White Plains lust 22 miles north VC Static Competition Make sure latest creation finished up polished youll have chance take home dozens trophies fered events Ww POST AMI Military POST I/RN NOc-MiIituyI PAtTERN SPORT BIPLANE OLD TIMERS SPORT PYLON GLIDERS HELICOPTERS SCALE RIC BOATS RACING RJC BOATS STAND-OFF SCALE JUNIOR EVENTS RIC CARS REST-IN-SHOW Judging takes place Sunday afternoon Entries accepted until 12Noon Sunday Openers/Winter continued page 6 center its side area lies sufficiently behind CG make tracklike feathers arrow profile weathervane traditional argument CLA too far above CG plane would forced spiral dive banked turned because skidding effect airflow outside circle exerting leverage proportion moment arm between CG CLA came Goldberg Zipper pylon gas model spiraled upward under power shook up hardline tradi tionalists long theory revised account two CLAs froffltthe CG andihetttherbehind line drawn between two would impart nose up SWAP SHOP WRAMs Swap Shop has become malor show attractions thousands individual items changing hands help eliminate registration crush 1980 Swap Shop will have special pre-registra lion line have com pleted pre-registration form receive forms send selfaddressed stamped envelope John Isbister 4 Devon Rd Larchmont NY 10528 SPECIAL NOTE Because increased volume items being brought Swap Shop combined space limita tions built-up model will accepted Swap Shop regis trant further informalion write Lam OiRubbo 16 Lindsey Ace Buchanan NY 10511 914 739-2827 WESTCHESTER RADIO AEROMODELERS INC February 23/21i 10AM 6 PM attitude forward CLA higher rearward inclination line barometer might say emphasis ward profile pattern airplane improve knife-edge example revised theory account Walt Mooneys comic free flights have no dihedral have huge funny pilot profile really fin sticking up cockpit really just same Low-speed aerodynamics never developed remotely compare full-scale knowledge cant make up minds smooth wing rough better fiddle turbulators multispars turbulate airflow over model wing presume keep flow breaking away prematurely top surface airfoiL So sounds contradic tory spanking new little scale model seems improve age patches dinks dents begin appear may fast once appears become flying carpet Reynolds Number mighty factor stern task master world indoor different youll agree fast pattern job RN goes up its best glass-like wings seems true FAI RC sailplanes full-scale world deals well-defined set rulesalthough reality great void between Cub ajet liner far wing efficiency lifting capacity concerned world appears level upon level note majestic flight 1/4 scale design parameters stretched like rubber bands seems tell us comparison full-scale aerody namics laws nature have left us modelers worlds still explore believe know everything know basic rules determine configur ation Consider fact awing must somehow stabilized hold its optimum position flight have ever seen free-flight wing depart model high sky rotate around some spanwise axis know what lack such stabilizing force really means As angle attack loose wing increases first pitch-up know thatthe center pressure lift moves forward airfoil destabilize flat plate like sheet balsa wing CL moves rearward Convex sections reduce distance CL will shift So can wing made stable no stabilizer present incorporate sweepback still have supply further stabilization wing twistex aggerated washout tips providing uptilted surfaces tips same purpose possible through airfoil variations other tricky stuff too devious consider limited space have stable flying plank Without hoopla will agree orthodox wing simply must stabilizing force stabilizer winglike horizontal area taiL Some years ago Mr Norman K Walker gave lecture members DC/RC entitled Stability Control Model Air craft long intriguing lecture presented diagrams variety strange models make points Among strange beastie shown accompanying photo graph Instead conventional stabilizer achieved necessary stability small flat plate mounted front high fin After have figured out will perceive notion ways skinning scat laws aerodynamics may fixed thing however strange confirming end employment model designer eloquently suggests adventures lie future draw precise airfoils yet majority sport models rubber gas radio otThand zip can perform just well better speak downwash angles put stab really knows downwash given model may slow molasses fast enough duplicate homebuilt speeds typical indoor model may weigh gram two rubber Consider wing loading would bet life model has tip vortices air pressure thing tip borders non-existent Would agitate tissue streamer aerodynamics science itmeanders still waters low Reynolds Numbers work some cases Low speed aerodynamics know proves mans educated guess good anothers may Continued page 96 72 Model Aviation assou,c ao,c/TONES EN0AN0 aC es0EOss N rare 55551W 4t 00 ii-0 4 0 0 two classics Flyline COMING SOON 11/2 Scale Farman Moustique READY NOW 47iiCO BO Products BOBCO parts factory parts replacement parts manufactured BOBCO Call Write Complete Information Entire Line DEALER PROGRAMS ENCOURAGED SEE YOUR LOCAL HOBBY DEALER send 25f catalog _____________34 span ower single channel or$1595 free flight OUAKER FLASH FLYLINE MODELS INC 2820 DOAR AVENUE B-Il FAIRFAX VIRGINIA 22031 703 573-2030 BLADES JET RANGER$1295 ALLOUETE$1295 COMMANDER$895 HELIBOY$895 HELIBABY$495 REVOLUTION 1$495 ROTOR SHAFTS HELIBABY$495 COMMANDER$995 REVOLUTION 1$495 FAN SHROUDS 40 60 size$795 Have AMERICAN KAVAN Helicoptors parts DISCOUNT PRICES 10% Discount 5 Sets CA residents add 6% sales tax2504 C-i S Santa Fe Avenue add $150 postage & handlingVista CA 92083 check moncy order toTel 714 727 41304 Openers/Winter continued page 72 forgiven being doubting Thomas Everything completely obvious scrutable Quarter- Scale movement biggies general apparently has encountered its first headache dire predictions having far fallen faces problem did show itself proved electronic Gremlin-like nature does affect such craft perhaps unlucky victim phenomena wont find very funny According memorandum AMA Frequency Committee RC Modelers RC Radio Manufacturers sent Quarter-Scale Association some planes just flat unflyable Noise ancient nemesis caused universal grief some years ago like insects develop immunity pesticides once again major challenge Present radios have dealt problem ordinary airplanes biggies ordinary airplanes know importance avoiding metal-to-metal contacts though modem radios have eliminated great deal such self-generated interference padded circuits noise resistant memo compared approach caging wild tiger some minor problem breaks lock hell can burst loose Large engines can vibrate like buzz saws metal fittings strength occasional ships require spiderweb rigging wires No mention made cable control wires running over place possible interaction between things servo cables antennas possibly wires cables may create other spooky problems though FO quali fied wonder Fortunately QSAA has world-wide experience conclusive evidence FM radios eliminate problem memo urges drive obtain FCC approval FM frequencies will report now matter being pursued AMA FCC receptive granting new FM frequencies RC will reading about AMA section magazine action unfolds editor fully convinced contact quarter-scaler friends problem can acute has unflyable 60-powered job flight disaster spite interchang ing Kraft Futaba systems have file expensive project also manufactured some later date both designer manufacturer ask us run warning note may unflyable manufacturer has post poned full line lovely biggies afraid flight test until answer found Mean takes good old AMA get frequencies AMA s current effort may solve problem Whatever outcome takes oh much timeit encouraging see alert QSAA effective on-the-ball organization getting word out warn others John Prestons column Safety month may important thing have ever read has unpleasant things say about fatal accidents flying CL models near powerlines editor helm ofMANmany years ago record kept fatalities appeared both US British newspapers ten-year period count stood 16 prior 1960 Preston mentions eight over past six years Manufacturers have driven out businessand constant threat radio too other reasonssince todays practice people sue everyone sight manufacturers props wheels parts AMA itself free concern speak ing CL models writer Matty Sullivan once investigated matter power companies New York Philadelphiaboth printed literature combat problem advised Preston says model does actually have touch such lines control lines may metal told electrical current jumps gap will follow direction must try educate everyone far wide please report type model accident Preston guidance column Safety Preston continued page 25 coroners report may step closer having some outside legislation affecting hobby rest us DO NOT FLY NEAR OVERHEAD POWER LINES John Preston 7012 Elsira Ct Falls Church VA 22042 96 Model Aviation Norman Walker demonstration model referred FO the right wont fly efficiently normal model horizontal tail small flat plate ward slanted fin provides drag stabilizes airplane pitch Left Another oddities straight-winged tail-less 1/4 camber airfoil inverted After half out side loop following launching will stabilize fly invertedknew youd curious
Edition: Model Aviation - 1980/02
Page Numbers: 6, 72, 96
BILL WINTERS IONEi1Li3 erodynam icsis sci ence Since days vision aries dreamers going back before Wrights born countless minds have struggled its fundamentals studied wind tunnels laboratories evolved theories laws wartime its refine ment took quantum jumps lifetime have seen aviation advance step re lated sciences metallurgy electronics name just twofrom point new plane proved airworthy until daring test pilot tried out fre quently losing life todays ability project multi-million jumbo jet supersonic fighterwhich sold hundreds before prototype takes shape factory aerodynamic laws im mutable experimenter would seem thing past being nothing unknown discover restless minds continue divine new ways apply laws hand see engineering task forces equipped computers project craft desired characteristics performance capa city 747 other see designer equivalent old test pilot perceives laws outline never-ending areas things filled Convair F-i 02 refused break sound barrier Whitcomb came up coke bottle fuselage theory having cross sectional area its proper location machine whole devised winglet seen Varieze home-built new Learjet No aerodynamic magna charta can begin define infinite ways old laws can applied fornew answers Variations configurations pebbles beach refer normal differences between light plane airliner variations due intended purpose VTO blown wings lifting bodies deltas flying wings /N / C V 4 / nice cloverleaf iext time leave off etem canards circularwings name it exists world full-scale aerodynamics everything comes full circle However bizarre machine works confirms what rules science proscribe knows what other things finding Model aerodynamics cut try cut dried often argue over angels can dance head pin Although bound same laws nature sometimes seems different ballgame will debate until cows come home whether symmetrical airfoil mysteriously lifts zero degrees Fullscale engineers happen ac tive modelers remind us no uncertain terms impossibility Sure impossible but. impossible must provide mite up ship flying upright tad down flying inverted Yet fly things swear controlline stunter like RC pattern job will stay put will fly steadily reasonable time upright inverted once positioned feeding such tiny input arent aware Like horse can led water cannot made drink writer has open mind few dozen other modeling phenomena closed mind Darned know Joe Wagner one-time prominent kit designerthe Dakota biplane left thrust far anyone used before sinceand stated symmetrical airfoil somehow changes its angle ofattackorsomething such high frequency continuously oscillating seek its flyable angle eye cannot perceive Frank Zaic expounded circular air flow thing affects way model circles bankand weve debated least 25 years have heard center-of-lateral area debate still unsettled after good 40 years may never argue anyone pro con en couraged fact grand pappy used blow steam out ears argued about Friends have known talk other years because CIA such thing CLA writer thinks ne has weathercock stability presumed Continued page 72 6 Model Aviation Westchester County Center White Plains New York Dont miss 12th annual show Itll biggest best ever Keep last weekend February open 1980 WRAMs Show going largest yet Well over 150 manufacturers other ex hibiters have already signed up bring everything thats new hobby--- kits engines radi os accessories everything between famous Swap Shop will full operation thousands items including built-up planes almost new radios engines on something just about everyone Westchester County Center centrally located city White Plains N intersection RI 110 Central Park Ace. Oronx Ricer Parkway White Plains lust 22 miles north VC Static Competition Make sure latest creation finished up polished youll have chance take home dozens trophies fered events Ww POST AMI Military POST I/RN NOc-MiIituyI PAtTERN SPORT BIPLANE OLD TIMERS SPORT PYLON GLIDERS HELICOPTERS SCALE RIC BOATS RACING RJC BOATS STAND-OFF SCALE JUNIOR EVENTS RIC CARS REST-IN-SHOW Judging takes place Sunday afternoon Entries accepted until 12Noon Sunday Openers/Winter continued page 6 center its side area lies sufficiently behind CG make tracklike feathers arrow profile weathervane traditional argument CLA too far above CG plane would forced spiral dive banked turned because skidding effect airflow outside circle exerting leverage proportion moment arm between CG CLA came Goldberg Zipper pylon gas model spiraled upward under power shook up hardline tradi tionalists long theory revised account two CLAs froffltthe CG andihetttherbehind line drawn between two would impart nose up SWAP SHOP WRAMs Swap Shop has become malor show attractions thousands individual items changing hands help eliminate registration crush 1980 Swap Shop will have special pre-registra lion line have com pleted pre-registration form receive forms send selfaddressed stamped envelope John Isbister 4 Devon Rd Larchmont NY 10528 SPECIAL NOTE Because increased volume items being brought Swap Shop combined space limita tions built-up model will accepted Swap Shop regis trant further informalion write Lam OiRubbo 16 Lindsey Ace Buchanan NY 10511 914 739-2827 WESTCHESTER RADIO AEROMODELERS INC February 23/21i 10AM 6 PM attitude forward CLA higher rearward inclination line barometer might say emphasis ward profile pattern airplane improve knife-edge example revised theory account Walt Mooneys comic free flights have no dihedral have huge funny pilot profile really fin sticking up cockpit really just same Low-speed aerodynamics never developed remotely compare full-scale knowledge cant make up minds smooth wing rough better fiddle turbulators multispars turbulate airflow over model wing presume keep flow breaking away prematurely top surface airfoiL So sounds contradic tory spanking new little scale model seems improve age patches dinks dents begin appear may fast once appears become flying carpet Reynolds Number mighty factor stern task master world indoor different youll agree fast pattern job RN goes up its best glass-like wings seems true FAI RC sailplanes full-scale world deals well-defined set rulesalthough reality great void between Cub ajet liner far wing efficiency lifting capacity concerned world appears level upon level note majestic flight 1/4 scale design parameters stretched like rubber bands seems tell us comparison full-scale aerody namics laws nature have left us modelers worlds still explore believe know everything know basic rules determine configur ation Consider fact awing must somehow stabilized hold its optimum position flight have ever seen free-flight wing depart model high sky rotate around some spanwise axis know what lack such stabilizing force really means As angle attack loose wing increases first pitch-up know thatthe center pressure lift moves forward airfoil destabilize flat plate like sheet balsa wing CL moves rearward Convex sections reduce distance CL will shift So can wing made stable no stabilizer present incorporate sweepback still have supply further stabilization wing twistex aggerated washout tips providing uptilted surfaces tips same purpose possible through airfoil variations other tricky stuff too devious consider limited space have stable flying plank Without hoopla will agree orthodox wing simply must stabilizing force stabilizer winglike horizontal area taiL Some years ago Mr Norman K Walker gave lecture members DC/RC entitled Stability Control Model Air craft long intriguing lecture presented diagrams variety strange models make points Among strange beastie shown accompanying photo graph Instead conventional stabilizer achieved necessary stability small flat plate mounted front high fin After have figured out will perceive notion ways skinning scat laws aerodynamics may fixed thing however strange confirming end employment model designer eloquently suggests adventures lie future draw precise airfoils yet majority sport models rubber gas radio otThand zip can perform just well better speak downwash angles put stab really knows downwash given model may slow molasses fast enough duplicate homebuilt speeds typical indoor model may weigh gram two rubber Consider wing loading would bet life model has tip vortices air pressure thing tip borders non-existent Would agitate tissue streamer aerodynamics science itmeanders still waters low Reynolds Numbers work some cases Low speed aerodynamics know proves mans educated guess good anothers may Continued page 96 72 Model Aviation assou,c ao,c/TONES EN0AN0 aC es0EOss N rare 55551W 4t 00 ii-0 4 0 0 two classics Flyline COMING SOON 11/2 Scale Farman Moustique READY NOW 47iiCO BO Products BOBCO parts factory parts replacement parts manufactured BOBCO Call Write Complete Information Entire Line DEALER PROGRAMS ENCOURAGED SEE YOUR LOCAL HOBBY DEALER send 25f catalog _____________34 span ower single channel or$1595 free flight OUAKER FLASH FLYLINE MODELS INC 2820 DOAR AVENUE B-Il FAIRFAX VIRGINIA 22031 703 573-2030 BLADES JET RANGER$1295 ALLOUETE$1295 COMMANDER$895 HELIBOY$895 HELIBABY$495 REVOLUTION 1$495 ROTOR SHAFTS HELIBABY$495 COMMANDER$995 REVOLUTION 1$495 FAN SHROUDS 40 60 size$795 Have AMERICAN KAVAN Helicoptors parts DISCOUNT PRICES 10% Discount 5 Sets CA residents add 6% sales tax2504 C-i S Santa Fe Avenue add $150 postage & handlingVista CA 92083 check moncy order toTel 714 727 41304 Openers/Winter continued page 72 forgiven being doubting Thomas Everything completely obvious scrutable Quarter- Scale movement biggies general apparently has encountered its first headache dire predictions having far fallen faces problem did show itself proved electronic Gremlin-like nature does affect such craft perhaps unlucky victim phenomena wont find very funny According memorandum AMA Frequency Committee RC Modelers RC Radio Manufacturers sent Quarter-Scale Association some planes just flat unflyable Noise ancient nemesis caused universal grief some years ago like insects develop immunity pesticides once again major challenge Present radios have dealt problem ordinary airplanes biggies ordinary airplanes know importance avoiding metal-to-metal contacts though modem radios have eliminated great deal such self-generated interference padded circuits noise resistant memo compared approach caging wild tiger some minor problem breaks lock hell can burst loose Large engines can vibrate like buzz saws metal fittings strength occasional ships require spiderweb rigging wires No mention made cable control wires running over place possible interaction between things servo cables antennas possibly wires cables may create other spooky problems though FO quali fied wonder Fortunately QSAA has world-wide experience conclusive evidence FM radios eliminate problem memo urges drive obtain FCC approval FM frequencies will report now matter being pursued AMA FCC receptive granting new FM frequencies RC will reading about AMA section magazine action unfolds editor fully convinced contact quarter-scaler friends problem can acute has unflyable 60-powered job flight disaster spite interchang ing Kraft Futaba systems have file expensive project also manufactured some later date both designer manufacturer ask us run warning note may unflyable manufacturer has post poned full line lovely biggies afraid flight test until answer found Mean takes good old AMA get frequencies AMA s current effort may solve problem Whatever outcome takes oh much timeit encouraging see alert QSAA effective on-the-ball organization getting word out warn others John Prestons column Safety month may important thing have ever read has unpleasant things say about fatal accidents flying CL models near powerlines editor helm ofMANmany years ago record kept fatalities appeared both US British newspapers ten-year period count stood 16 prior 1960 Preston mentions eight over past six years Manufacturers have driven out businessand constant threat radio too other reasonssince todays practice people sue everyone sight manufacturers props wheels parts AMA itself free concern speak ing CL models writer Matty Sullivan once investigated matter power companies New York Philadelphiaboth printed literature combat problem advised Preston says model does actually have touch such lines control lines may metal told electrical current jumps gap will follow direction must try educate everyone far wide please report type model accident Preston guidance column Safety Preston continued page 25 coroners report may step closer having some outside legislation affecting hobby rest us DO NOT FLY NEAR OVERHEAD POWER LINES John Preston 7012 Elsira Ct Falls Church VA 22042 96 Model Aviation Norman Walker demonstration model referred FO the right wont fly efficiently normal model horizontal tail small flat plate ward slanted fin provides drag stabilizes airplane pitch Left Another oddities straight-winged tail-less 1/4 camber airfoil inverted After half out side loop following launching will stabilize fly invertedknew youd curious