IIEROIYNAM IC DArn NV 1GM NS INE U HAL DEBfl1 YOU ARE mainstream model activities se re never enough time what needs done get o e next action Along way see possibilities would like look needed time flies retire action unless rocking chair beckons time available investigate some ever get items thought have spent last two years investigating Some findings surprising seem worthy pass objective use basic aerodynamics find methods improving performance and/or solving problems Electrics current phase modeling make ideal vehicles research Like free flight models electric-powered Enduro designs must perform over wide speed range unlike free flight excess power available simply blast away Perfonnance easily observed differences quite apparent flight Unfortunately have sophisticated wind tunnels lot can learned comparative flying Successive flights can compared using different configurations flights made results have real vehicle still used basic Enduro design modified wings tails can interchanged force arrangements can altered high-performance design easily climbs out-of-sight much less minute glide mode also match best Thus flight change good bad easily observed comparisons simple comparative investigations involved wing airfoils wing planforms dihedral horizontal tail airfoils sizes/force arrangements center gravity CC location rudder responsiveness winglets None investigations developedfully areas uncovered indicated further development would warranted short positive results seen pointing improved performance give report continuity will begin wing since heart aircraft follow factors assure wing flies maximum efficiency should noted some factors investigated force arrangement altered compensate difference forces seen case done until appeared maximum performance achieved concept Airfoils compare airfoils obviously need separate wing eacha formidable task involved answer 36 Model Aviation ing done several high-performance electric Enduro models wings tails interchangeable EPPLER 193 EPPLER 176 DAVIS DAVIS Diagram Various wing planforms comparatively flown Schuemann version far right has winglets added choose four proven airfoils would indicate what expect anything similar nature started Eppler 193 widely used electricpowered Enduros Performance excellent formed basis comparison did appear bit touchy longitudinal stability controlled judicious adjustments force arrangement second airfoil investigated Eppler 176 major difference between two airfoils 176 about 20% thinner 193 wing creating major aircraft drag thinner airfoil should result less drag higher flying speed questions whether higher flying speed would allow thinner section equal lift thicker whether rate climb would greater Comparative flying indicated higher flying speed gave increased rate climb higher speed proved distinct advantage thermal hunting windy conditions slowed down match 193s flying speed higher rate sink obvious speed increased liking 176 sink rate became comparable Bottom line 176 needs fly faster many modeling years numerous types models have found performance Davis airfoils outstanding provided excellent lift stability plus low drag strong desire compare Eppler Davis sections however Davis airfoils familiar included undercamber associated drag could expected Fortunately found flat-bottom version John Malkin s fine airfoil book Davis section identical thickness Eppler 193 comparative flying immediately noticed Davis 193 wings could readily interchanged no adjustments required found Davis tolerant CG changes Eppler effect its stability remained intact farther-aft CG aft CG allowed use tail lift equates total lift added tail lift also asset controlling power Over long haul comparative flying three airfoils Davis did seem have advantage under normal flying conditions However edge would have go Eppler 176 windy weather last airfoil tested wonder what would happen investigations Theory tells us can expect lift August1993 37 POLYHEDRAL POLYHEDRAL STRAIGHT SCHUEMANN PARABOLIC SCHUEMANN Diagram 2 full flying rudder gave positive yaw control speeds long strip hinge attaches fuselage Part II author will investigate horizontal tail areas airfoilsother elements comparative flying CENTURY MODELS INC 8 Martha Ct8305 Regency Woods Way Sumter SC 29150Louisville KY 40220 803 775-6491502 491-4114 RETRACT SELECTOR SPEED CONTROL VALVE Four Infinite Adjustment Screws 2 Up 2 Down Compatible air system Dim 3/8 s1 s 1-114$2495 WI 15 oz Semi & Deluxe Ducted Fan Jet Kits Eposy fiberglass fuselage canopy foam wings plans instructions Intake/Eshaust System euc F-ba F-100 Hun basic kit $18999 1/8 Scale 50 Removable Wings Length 63 Sport Hawk MK U basic kit $18988 Easy build Removable wing th 59 F-105 Thunderchief basic kit $23900 Length 73" 77-91 Engine heater Hole F4 Phantom basic kit $59900 NEW 1/7 Scale Twin Engine Aileron/Spoiler Config Length 90 vable 61 Wings E flaps Deluse kit DC wood I/B pylons CP kit plus morel Landing gear tires brakes available COMPARE OUR RETRACTS TO THEIRS Stainless Struts cut FREE Stainless Torque Links Different strut configurations 1 Year Limited Warranty GIANT MAIN RETRACTS STANDARD OR 900 ROTATI 30-50 lb aircraft 2 sets 1 Standard 9Q0 minutes 700 11 QO retract angle Over-center lock down Nose gear available $27500 pair Wt 15 lbs Complete Air System Axle Installed Parts Service 30 Day Retundf r15 SCALE MAIN RETRACTS STANDARD OR 900 ROTATE Fits PICA Skys P-Si 1/5 Yellow NC Ziroli Bud Nosen plus Choice 91 Plyon Winners Handles 20-25 lb aircraft 540 970 retract angle Positive lock up lock down Optional wire struts Nose gear available $19900 pair WI 22 oz NEW 1/5 SCALE P-51 & SPITFIRE products proudly MADE IN THE USA AILABIENew 2-Cvcle 40 &un Aluminum Airplane Coming Soon Smoker Preheaters Are Twice Enjoy Flying As Effective As Head Coils Funflys & Complete Smoker System 2-Cycle & 4-Cycle MakingEngines Includes preheater pressure control valve smoker valve tubing pressure taps check valve Little Extra lete instructions Weekend MoneyMoney Back Guarantee CALL 1-912-367-0567 Visa Mastercard &/L4/IJ 1 American Ex ess CALL OR WRITEYAMERICAN MODEL PRODUCTS Inc FOR DETAILSAccePte4RT3 BOX 57BAXLEY GA31513 Become Part Time battery needs call write B&P Associates PO Box 22054 Waco TX 76702-2054 817662-5587 new electric starter battery pack Cuts cord has always tied starter power panel Discover freedom being able start plane wherever added safety less wire get caught prop charge hefty 4 Amp/hour pack will take through weekend flying power enough spare dont stop have Ni-Cads virtually size imaginable cut experimenter free design whatever takes make yours best setup field airfoil features undercamber would like lift however additional drag would detriment rate climban equally important consideration question became could gain added undercamber lift increasing drag over flat-bottom section clue came FF fraternity fundamental factor has use very thin undercambered airfoils needed determine whether drag thin undercambered airfoil would equal normal flat-bottom section whether would increase lift evaluate thinking chose reduce normal 11% thickness Davis #5 airfoil 7% As sidelight can see 10-inch chord has thickness less 3/4 inch could strength problem am happy report particular stressedskin structure has proven adequate complete range flying conditions Comparative flying thin undercambered airfoil immediately opened eyes Simply interchanging wing others produced vicious stalling tendencya strong indication lift being produced obtain satisfactory performance radical change made force arrangement Increasing tail lift removed power-on stall resulted nose-down attitude glide mode obvious section much sensitive speed changes final change produced satisfactory overall performance move CG back proper position relative new mean centerline created excellent glide mode affecting power mode So does thin undercambered section compare other airfoils gliding power-on speeds rate climb comparable Eppler 193 Davis airfoils However Eppler 176 quicker respects rate sink average conditions also similar pronounced asset quite apparent undercambered airfoil does respond light lift readily better others could due combi nation elements involved configuration However should noted airfoil allows change elements Summary After effort factor stands out Considering performance differences seen between some airfoils general performance of would acceptable Enduro flying differences seen might suit some particular need Eppler 176 windy conditions thin undercambered section light lift etc Sorry no great magic found astound Dihedral We see numerous gliders exotic Electrics apparently flying well little no dihedral objective regain lift lost normal dihedral 38 Model Aviation Associates Gives Total Flight Line FREEDOM angles used negative factor apparent need use ailerons directional control might ask whether additional weight complexity ailerons outweigh gain lift second question could whether use dihedral adequate yaw control using rudder can alleviated experience indicated some dihedral effect asset lateral stability creating flatter turns also found minimum dihedral sufficient investigation included minimum amount dihedral comparing polyhedral effect straight dihedral obtaining suitable yaw control rudder comparison base used classic polyhedral low angles used proved no shortage stability However rudder control very soft especially low speeds typical gliders Electrics Another wing low straight dihedral yielded similar yawcontrol results least RC craft dihedral angles can kept minimum no adverse results Polyhedral appeared provide no benefit hence its complexity could eliminated Yaw control rudder/fin typical size location models type initially used Under power glide mode proved usable altitude although response time slower might like minimum flight speeds might seen landing approach often wondered rudder quit working best situation far cure use full flying rudderfin pivoted tA-chord point very much like what used WW pursuit planes initial powered launch arrangement shocked slight yaw correction desireda normal application rudder yawed model complete 900 Directional control used kid gloves rest flight next flight normal amount rudder deflection cut half Since have nothing positive instanta neous yaw control under circumstances Would concept adequate flat wings place ailerons could assumed yaw control would adequate would rudder action raise dropped wing ailerons So far Ijust havent opportunity investigate Wing planforms classic FF-style wing planform especially polyhedral used long straight center panel tapered tips Such shape has always provided excellent performance basis comparisons Some time back much ado media plus positive reports modelers expounding virtues Schuemann wing planform felt worthy attention straight-dihedral wing using Schuemann parameters verbatim produced flown first indication difference Continued page 42 U 4 0AFTED 395O-AValietBlvd WALNUT CA 91789N C uJ 4 W T PE RR 0 0 F CALL OR WRITE FOR FREE BROCHURE August1993 39 QtLALIIY TrEGUTY SWICE UALrIY PITEGflTY SRviCE l2JJAtlTY IIITEGflTY SERVICE C S T FA RN ED EI 01 0 05 0 C 05 0 ii Tm SNAPPER fl/C COMBAT-STYLE SPORT MODEL FOR Gww OR ELECTRIC POWER * Kit includes illustrated usatructioce hardware pack formed canopy macbios- diecut parts made high-quality balsa plywood * May flown 05 electric power 049 11 glow engine power Parts izutnictiona both versiolsa included 5 Ofibta solid big-plane perfonuance Its small plane flies like 40$49 pts standard-size servos Wlngspan 34 inches Area 288 square inches Weight 7 ounces airframe 22 26 ounces ready fly glow powered 33 36 ounces y fly electric powered 562w Srhrork Rosd westarvitte Ohio 43051 manufactured by AEROCRAFT dutuibuted Capstone fl/C Suppliers Call 1-800-593-5250 LDM Industries Inc THE INTRODUCES.. STRONGBOXTM RECEIVER AND BAlTERY PACK PROTECTION SYSTEM STRONGBOX revolutionary new product designed toprovideboth vibration crash protection receiver battery pack TheSTRONGBOXis molded tough polypropylene plastic lined vibration absorbing foam STRONGBOX designed mount model just like servo tray included mounting hardware Measuring lflf&nOl cut-away Off lie bTI RVNGBOXTM 24 inches deep 27 inches wide 41 inches long STRONGBOX will fit 40 hrger sized models 19 ounces including foam padding mounting hardware STRONGBOX weighs about same standard size servo receiver battery pack valuable components R/C control system Give vibration crash protection need deserve Protect valuables STRONGBOX Part #8000 795 U1~vA a1 Due overwhelming response Anniversary Sale have decided permanently lower retail price entire line Ball Bearing Servo Conversion Kits way saying thanks continuing support products company Futaba S28 S38 S48 S128 S138 S148 Cirrus S28 CS1 28 CS238 & C5248 servos Kit #9600 4 pack ..$2995 Kit #9610 1 pack..$ 795 Airtronics 94102 servos Kit #9700 4 pack ..$2995 Kit #9710 1 pack..$ 795 JR 501 & 507 Focus H5300 RCD 05 Tower TS-51 Hobbico CS-SI Ace 330 servos Kit #9800 4 pack ..$2095 Kit #9810 1 pack..$595 NO-HEAT Tiuivi SOLXTENTTM Takes Hassle Out Monokote Trim Work Bonds Monokote aver Monokote beat Eliminates ugly bubbles wrinkles Completely fuel-proof easy use WiIl cause colors bleed Allows time position trim pieces Also works Ultracote Oracover Part #95004 oz Bottle 01 Upgrale 4 standard servos less cost bell bearing servo LDM Industries Ball Bearing Servo Conversion Kits will Eliminate wobble output shaft Reduce control response deadhand Reduce chance flutter hnprove control surface centering Allow use pull-pull cables Florida residents add 6 1125 sales tax VISA MASTER CARD Accepted Dealer Inquiries Welcome C 1993 LDM Industries Inc AerodynamicldeBolt Continued page 39 need move CC back sweptback tips obviously moved center lift rearward After required trim change numerous comparative flights made no outstanding difference However did appear slight increase penetration questionable increase liftno worse classic wing sure possible plus factor Another planform time tells us should acme shapes elliptical outline Schuemana planform has leading edge sharp changes direction Fundamental drag factors dictate sharp contour changes no-no respects raised another question Could Schuemana planform improved using parabolic curve remove sharp breaks seemed worth try took Schuemann layout developed parabolic curve intersected Schuemana parameter points nothing else produced pretty look birdlike wing would great able say comparative flights sensational real story have look closely observe real difference can say gains similar seen true Schuemann shape however time pronounced parabolic planform appears efficient lot small way canard final planform worthy mention because might solve nasty problem such tail-heavy design no other suitable cure consideration get center wing lift far enough back balance purposes Using KISS Keep Simple Stupid principle initial effort used typical EF-style polyhedral wing Normally planform uses equal taper tip LE TE canard put taper LE swept tips back speak first flew wing normal configuration As initial Schuemann flights center lift obviously much farther back normal After required CC trim change wing compared very closely classic wing appears possible cure tail-heavy condition sweeping wing tips aft conclude wing investigations believe low straight-dihedral parabolic Schuemann planform thin airfoil greatest efficiency results comparative flying wing planforms would very similar seen airfoils probably no planform vastly superior provided stray far established path Aerodynamic Investigations will con clude second segment will de scribe extensive investigations horizontal tails force arrangements winglets odel Aviation ARRANTY WHAT VE SELLI Factory Authorized E-Z UP Corp Dealer John Peck Leisure Products Ltd 131 RAVENWOOD RD AILLES KY 873- 1/21 order send check money order including 30O S&H LDM Industries Inc PO Box 2923% Dept 140 Tampa FL 33687-2396 Phone/Fax 813 985-5616
Edition: Model Aviation - 1993/08
Page Numbers: 36, 37, 38, 39, 42
IIEROIYNAM IC DArn NV 1GM NS INE U HAL DEBfl1 YOU ARE mainstream model activities se re never enough time what needs done get o e next action Along way see possibilities would like look needed time flies retire action unless rocking chair beckons time available investigate some ever get items thought have spent last two years investigating Some findings surprising seem worthy pass objective use basic aerodynamics find methods improving performance and/or solving problems Electrics current phase modeling make ideal vehicles research Like free flight models electric-powered Enduro designs must perform over wide speed range unlike free flight excess power available simply blast away Perfonnance easily observed differences quite apparent flight Unfortunately have sophisticated wind tunnels lot can learned comparative flying Successive flights can compared using different configurations flights made results have real vehicle still used basic Enduro design modified wings tails can interchanged force arrangements can altered high-performance design easily climbs out-of-sight much less minute glide mode also match best Thus flight change good bad easily observed comparisons simple comparative investigations involved wing airfoils wing planforms dihedral horizontal tail airfoils sizes/force arrangements center gravity CC location rudder responsiveness winglets None investigations developedfully areas uncovered indicated further development would warranted short positive results seen pointing improved performance give report continuity will begin wing since heart aircraft follow factors assure wing flies maximum efficiency should noted some factors investigated force arrangement altered compensate difference forces seen case done until appeared maximum performance achieved concept Airfoils compare airfoils obviously need separate wing eacha formidable task involved answer 36 Model Aviation ing done several high-performance electric Enduro models wings tails interchangeable EPPLER 193 EPPLER 176 DAVIS DAVIS Diagram Various wing planforms comparatively flown Schuemann version far right has winglets added choose four proven airfoils would indicate what expect anything similar nature started Eppler 193 widely used electricpowered Enduros Performance excellent formed basis comparison did appear bit touchy longitudinal stability controlled judicious adjustments force arrangement second airfoil investigated Eppler 176 major difference between two airfoils 176 about 20% thinner 193 wing creating major aircraft drag thinner airfoil should result less drag higher flying speed questions whether higher flying speed would allow thinner section equal lift thicker whether rate climb would greater Comparative flying indicated higher flying speed gave increased rate climb higher speed proved distinct advantage thermal hunting windy conditions slowed down match 193s flying speed higher rate sink obvious speed increased liking 176 sink rate became comparable Bottom line 176 needs fly faster many modeling years numerous types models have found performance Davis airfoils outstanding provided excellent lift stability plus low drag strong desire compare Eppler Davis sections however Davis airfoils familiar included undercamber associated drag could expected Fortunately found flat-bottom version John Malkin s fine airfoil book Davis section identical thickness Eppler 193 comparative flying immediately noticed Davis 193 wings could readily interchanged no adjustments required found Davis tolerant CG changes Eppler effect its stability remained intact farther-aft CG aft CG allowed use tail lift equates total lift added tail lift also asset controlling power Over long haul comparative flying three airfoils Davis did seem have advantage under normal flying conditions However edge would have go Eppler 176 windy weather last airfoil tested wonder what would happen investigations Theory tells us can expect lift August1993 37 POLYHEDRAL POLYHEDRAL STRAIGHT SCHUEMANN PARABOLIC SCHUEMANN Diagram 2 full flying rudder gave positive yaw control speeds long strip hinge attaches fuselage Part II author will investigate horizontal tail areas airfoilsother elements comparative flying CENTURY MODELS INC 8 Martha Ct8305 Regency Woods Way Sumter SC 29150Louisville KY 40220 803 775-6491502 491-4114 RETRACT SELECTOR SPEED CONTROL VALVE Four Infinite Adjustment Screws 2 Up 2 Down Compatible air system Dim 3/8 s1 s 1-114$2495 WI 15 oz Semi & Deluxe Ducted Fan Jet Kits Eposy fiberglass fuselage canopy foam wings plans instructions Intake/Eshaust System euc F-ba F-100 Hun basic kit $18999 1/8 Scale 50 Removable Wings Length 63 Sport Hawk MK U basic kit $18988 Easy build Removable wing th 59 F-105 Thunderchief basic kit $23900 Length 73" 77-91 Engine heater Hole F4 Phantom basic kit $59900 NEW 1/7 Scale Twin Engine Aileron/Spoiler Config Length 90 vable 61 Wings E flaps Deluse kit DC wood I/B pylons CP kit plus morel Landing gear tires brakes available COMPARE OUR RETRACTS TO THEIRS Stainless Struts cut FREE Stainless Torque Links Different strut configurations 1 Year Limited Warranty GIANT MAIN RETRACTS STANDARD OR 900 ROTATI 30-50 lb aircraft 2 sets 1 Standard 9Q0 minutes 700 11 QO retract angle Over-center lock down Nose gear available $27500 pair Wt 15 lbs Complete Air System Axle Installed Parts Service 30 Day Retundf r15 SCALE MAIN RETRACTS STANDARD OR 900 ROTATE Fits PICA Skys P-Si 1/5 Yellow NC Ziroli Bud Nosen plus Choice 91 Plyon Winners Handles 20-25 lb aircraft 540 970 retract angle Positive lock up lock down Optional wire struts Nose gear available $19900 pair WI 22 oz NEW 1/5 SCALE P-51 & SPITFIRE products proudly MADE IN THE USA AILABIENew 2-Cvcle 40 &un Aluminum Airplane Coming Soon Smoker Preheaters Are Twice Enjoy Flying As Effective As Head Coils Funflys & Complete Smoker System 2-Cycle & 4-Cycle MakingEngines Includes preheater pressure control valve smoker valve tubing pressure taps check valve Little Extra lete instructions Weekend MoneyMoney Back Guarantee CALL 1-912-367-0567 Visa Mastercard &/L4/IJ 1 American Ex ess CALL OR WRITEYAMERICAN MODEL PRODUCTS Inc FOR DETAILSAccePte4RT3 BOX 57BAXLEY GA31513 Become Part Time battery needs call write B&P Associates PO Box 22054 Waco TX 76702-2054 817662-5587 new electric starter battery pack Cuts cord has always tied starter power panel Discover freedom being able start plane wherever added safety less wire get caught prop charge hefty 4 Amp/hour pack will take through weekend flying power enough spare dont stop have Ni-Cads virtually size imaginable cut experimenter free design whatever takes make yours best setup field airfoil features undercamber would like lift however additional drag would detriment rate climban equally important consideration question became could gain added undercamber lift increasing drag over flat-bottom section clue came FF fraternity fundamental factor has use very thin undercambered airfoils needed determine whether drag thin undercambered airfoil would equal normal flat-bottom section whether would increase lift evaluate thinking chose reduce normal 11% thickness Davis #5 airfoil 7% As sidelight can see 10-inch chord has thickness less 3/4 inch could strength problem am happy report particular stressedskin structure has proven adequate complete range flying conditions Comparative flying thin undercambered airfoil immediately opened eyes Simply interchanging wing others produced vicious stalling tendencya strong indication lift being produced obtain satisfactory performance radical change made force arrangement Increasing tail lift removed power-on stall resulted nose-down attitude glide mode obvious section much sensitive speed changes final change produced satisfactory overall performance move CG back proper position relative new mean centerline created excellent glide mode affecting power mode So does thin undercambered section compare other airfoils gliding power-on speeds rate climb comparable Eppler 193 Davis airfoils However Eppler 176 quicker respects rate sink average conditions also similar pronounced asset quite apparent undercambered airfoil does respond light lift readily better others could due combi nation elements involved configuration However should noted airfoil allows change elements Summary After effort factor stands out Considering performance differences seen between some airfoils general performance of would acceptable Enduro flying differences seen might suit some particular need Eppler 176 windy conditions thin undercambered section light lift etc Sorry no great magic found astound Dihedral We see numerous gliders exotic Electrics apparently flying well little no dihedral objective regain lift lost normal dihedral 38 Model Aviation Associates Gives Total Flight Line FREEDOM angles used negative factor apparent need use ailerons directional control might ask whether additional weight complexity ailerons outweigh gain lift second question could whether use dihedral adequate yaw control using rudder can alleviated experience indicated some dihedral effect asset lateral stability creating flatter turns also found minimum dihedral sufficient investigation included minimum amount dihedral comparing polyhedral effect straight dihedral obtaining suitable yaw control rudder comparison base used classic polyhedral low angles used proved no shortage stability However rudder control very soft especially low speeds typical gliders Electrics Another wing low straight dihedral yielded similar yawcontrol results least RC craft dihedral angles can kept minimum no adverse results Polyhedral appeared provide no benefit hence its complexity could eliminated Yaw control rudder/fin typical size location models type initially used Under power glide mode proved usable altitude although response time slower might like minimum flight speeds might seen landing approach often wondered rudder quit working best situation far cure use full flying rudderfin pivoted tA-chord point very much like what used WW pursuit planes initial powered launch arrangement shocked slight yaw correction desireda normal application rudder yawed model complete 900 Directional control used kid gloves rest flight next flight normal amount rudder deflection cut half Since have nothing positive instanta neous yaw control under circumstances Would concept adequate flat wings place ailerons could assumed yaw control would adequate would rudder action raise dropped wing ailerons So far Ijust havent opportunity investigate Wing planforms classic FF-style wing planform especially polyhedral used long straight center panel tapered tips Such shape has always provided excellent performance basis comparisons Some time back much ado media plus positive reports modelers expounding virtues Schuemann wing planform felt worthy attention straight-dihedral wing using Schuemann parameters verbatim produced flown first indication difference Continued page 42 U 4 0AFTED 395O-AValietBlvd WALNUT CA 91789N C uJ 4 W T PE RR 0 0 F CALL OR WRITE FOR FREE BROCHURE August1993 39 QtLALIIY TrEGUTY SWICE UALrIY PITEGflTY SRviCE l2JJAtlTY IIITEGflTY SERVICE C S T FA RN ED EI 01 0 05 0 C 05 0 ii Tm SNAPPER fl/C COMBAT-STYLE SPORT MODEL FOR Gww OR ELECTRIC POWER * Kit includes illustrated usatructioce hardware pack formed canopy macbios- diecut parts made high-quality balsa plywood * May flown 05 electric power 049 11 glow engine power Parts izutnictiona both versiolsa included 5 Ofibta solid big-plane perfonuance Its small plane flies like 40$49 pts standard-size servos Wlngspan 34 inches Area 288 square inches Weight 7 ounces airframe 22 26 ounces ready fly glow powered 33 36 ounces y fly electric powered 562w Srhrork Rosd westarvitte Ohio 43051 manufactured by AEROCRAFT dutuibuted Capstone fl/C Suppliers Call 1-800-593-5250 LDM Industries Inc THE INTRODUCES.. STRONGBOXTM RECEIVER AND BAlTERY PACK PROTECTION SYSTEM STRONGBOX revolutionary new product designed toprovideboth vibration crash protection receiver battery pack TheSTRONGBOXis molded tough polypropylene plastic lined vibration absorbing foam STRONGBOX designed mount model just like servo tray included mounting hardware Measuring lflf&nOl cut-away Off lie bTI RVNGBOXTM 24 inches deep 27 inches wide 41 inches long STRONGBOX will fit 40 hrger sized models 19 ounces including foam padding mounting hardware STRONGBOX weighs about same standard size servo receiver battery pack valuable components R/C control system Give vibration crash protection need deserve Protect valuables STRONGBOX Part #8000 795 U1~vA a1 Due overwhelming response Anniversary Sale have decided permanently lower retail price entire line Ball Bearing Servo Conversion Kits way saying thanks continuing support products company Futaba S28 S38 S48 S128 S138 S148 Cirrus S28 CS1 28 CS238 & C5248 servos Kit #9600 4 pack ..$2995 Kit #9610 1 pack..$ 795 Airtronics 94102 servos Kit #9700 4 pack ..$2995 Kit #9710 1 pack..$ 795 JR 501 & 507 Focus H5300 RCD 05 Tower TS-51 Hobbico CS-SI Ace 330 servos Kit #9800 4 pack ..$2095 Kit #9810 1 pack..$595 NO-HEAT Tiuivi SOLXTENTTM Takes Hassle Out Monokote Trim Work Bonds Monokote aver Monokote beat Eliminates ugly bubbles wrinkles Completely fuel-proof easy use WiIl cause colors bleed Allows time position trim pieces Also works Ultracote Oracover Part #95004 oz Bottle 01 Upgrale 4 standard servos less cost bell bearing servo LDM Industries Ball Bearing Servo Conversion Kits will Eliminate wobble output shaft Reduce control response deadhand Reduce chance flutter hnprove control surface centering Allow use pull-pull cables Florida residents add 6 1125 sales tax VISA MASTER CARD Accepted Dealer Inquiries Welcome C 1993 LDM Industries Inc AerodynamicldeBolt Continued page 39 need move CC back sweptback tips obviously moved center lift rearward After required trim change numerous comparative flights made no outstanding difference However did appear slight increase penetration questionable increase liftno worse classic wing sure possible plus factor Another planform time tells us should acme shapes elliptical outline Schuemana planform has leading edge sharp changes direction Fundamental drag factors dictate sharp contour changes no-no respects raised another question Could Schuemana planform improved using parabolic curve remove sharp breaks seemed worth try took Schuemann layout developed parabolic curve intersected Schuemana parameter points nothing else produced pretty look birdlike wing would great able say comparative flights sensational real story have look closely observe real difference can say gains similar seen true Schuemann shape however time pronounced parabolic planform appears efficient lot small way canard final planform worthy mention because might solve nasty problem such tail-heavy design no other suitable cure consideration get center wing lift far enough back balance purposes Using KISS Keep Simple Stupid principle initial effort used typical EF-style polyhedral wing Normally planform uses equal taper tip LE TE canard put taper LE swept tips back speak first flew wing normal configuration As initial Schuemann flights center lift obviously much farther back normal After required CC trim change wing compared very closely classic wing appears possible cure tail-heavy condition sweeping wing tips aft conclude wing investigations believe low straight-dihedral parabolic Schuemann planform thin airfoil greatest efficiency results comparative flying wing planforms would very similar seen airfoils probably no planform vastly superior provided stray far established path Aerodynamic Investigations will con clude second segment will de scribe extensive investigations horizontal tails force arrangements winglets odel Aviation ARRANTY WHAT VE SELLI Factory Authorized E-Z UP Corp Dealer John Peck Leisure Products Ltd 131 RAVENWOOD RD AILLES KY 873- 1/21 order send check money order including 30O S&H LDM Industries Inc PO Box 2923% Dept 140 Tampa FL 33687-2396 Phone/Fax 813 985-5616
Edition: Model Aviation - 1993/08
Page Numbers: 36, 37, 38, 39, 42
IIEROIYNAM IC DArn NV 1GM NS INE U HAL DEBfl1 YOU ARE mainstream model activities se re never enough time what needs done get o e next action Along way see possibilities would like look needed time flies retire action unless rocking chair beckons time available investigate some ever get items thought have spent last two years investigating Some findings surprising seem worthy pass objective use basic aerodynamics find methods improving performance and/or solving problems Electrics current phase modeling make ideal vehicles research Like free flight models electric-powered Enduro designs must perform over wide speed range unlike free flight excess power available simply blast away Perfonnance easily observed differences quite apparent flight Unfortunately have sophisticated wind tunnels lot can learned comparative flying Successive flights can compared using different configurations flights made results have real vehicle still used basic Enduro design modified wings tails can interchanged force arrangements can altered high-performance design easily climbs out-of-sight much less minute glide mode also match best Thus flight change good bad easily observed comparisons simple comparative investigations involved wing airfoils wing planforms dihedral horizontal tail airfoils sizes/force arrangements center gravity CC location rudder responsiveness winglets None investigations developedfully areas uncovered indicated further development would warranted short positive results seen pointing improved performance give report continuity will begin wing since heart aircraft follow factors assure wing flies maximum efficiency should noted some factors investigated force arrangement altered compensate difference forces seen case done until appeared maximum performance achieved concept Airfoils compare airfoils obviously need separate wing eacha formidable task involved answer 36 Model Aviation ing done several high-performance electric Enduro models wings tails interchangeable EPPLER 193 EPPLER 176 DAVIS DAVIS Diagram Various wing planforms comparatively flown Schuemann version far right has winglets added choose four proven airfoils would indicate what expect anything similar nature started Eppler 193 widely used electricpowered Enduros Performance excellent formed basis comparison did appear bit touchy longitudinal stability controlled judicious adjustments force arrangement second airfoil investigated Eppler 176 major difference between two airfoils 176 about 20% thinner 193 wing creating major aircraft drag thinner airfoil should result less drag higher flying speed questions whether higher flying speed would allow thinner section equal lift thicker whether rate climb would greater Comparative flying indicated higher flying speed gave increased rate climb higher speed proved distinct advantage thermal hunting windy conditions slowed down match 193s flying speed higher rate sink obvious speed increased liking 176 sink rate became comparable Bottom line 176 needs fly faster many modeling years numerous types models have found performance Davis airfoils outstanding provided excellent lift stability plus low drag strong desire compare Eppler Davis sections however Davis airfoils familiar included undercamber associated drag could expected Fortunately found flat-bottom version John Malkin s fine airfoil book Davis section identical thickness Eppler 193 comparative flying immediately noticed Davis 193 wings could readily interchanged no adjustments required found Davis tolerant CG changes Eppler effect its stability remained intact farther-aft CG aft CG allowed use tail lift equates total lift added tail lift also asset controlling power Over long haul comparative flying three airfoils Davis did seem have advantage under normal flying conditions However edge would have go Eppler 176 windy weather last airfoil tested wonder what would happen investigations Theory tells us can expect lift August1993 37 POLYHEDRAL POLYHEDRAL STRAIGHT SCHUEMANN PARABOLIC SCHUEMANN Diagram 2 full flying rudder gave positive yaw control speeds long strip hinge attaches fuselage Part II author will investigate horizontal tail areas airfoilsother elements comparative flying CENTURY MODELS INC 8 Martha Ct8305 Regency Woods Way Sumter SC 29150Louisville KY 40220 803 775-6491502 491-4114 RETRACT SELECTOR SPEED CONTROL VALVE Four Infinite Adjustment Screws 2 Up 2 Down Compatible air system Dim 3/8 s1 s 1-114$2495 WI 15 oz Semi & Deluxe Ducted Fan Jet Kits Eposy fiberglass fuselage canopy foam wings plans instructions Intake/Eshaust System euc F-ba F-100 Hun basic kit $18999 1/8 Scale 50 Removable Wings Length 63 Sport Hawk MK U basic kit $18988 Easy build Removable wing th 59 F-105 Thunderchief basic kit $23900 Length 73" 77-91 Engine heater Hole F4 Phantom basic kit $59900 NEW 1/7 Scale Twin Engine Aileron/Spoiler Config Length 90 vable 61 Wings E flaps Deluse kit DC wood I/B pylons CP kit plus morel Landing gear tires brakes available COMPARE OUR RETRACTS TO THEIRS Stainless Struts cut FREE Stainless Torque Links Different strut configurations 1 Year Limited Warranty GIANT MAIN RETRACTS STANDARD OR 900 ROTATI 30-50 lb aircraft 2 sets 1 Standard 9Q0 minutes 700 11 QO retract angle Over-center lock down Nose gear available $27500 pair Wt 15 lbs Complete Air System Axle Installed Parts Service 30 Day Retundf r15 SCALE MAIN RETRACTS STANDARD OR 900 ROTATE Fits PICA Skys P-Si 1/5 Yellow NC Ziroli Bud Nosen plus Choice 91 Plyon Winners Handles 20-25 lb aircraft 540 970 retract angle Positive lock up lock down Optional wire struts Nose gear available $19900 pair WI 22 oz NEW 1/5 SCALE P-51 & SPITFIRE products proudly MADE IN THE USA AILABIENew 2-Cvcle 40 &un Aluminum Airplane Coming Soon Smoker Preheaters Are Twice Enjoy Flying As Effective As Head Coils Funflys & Complete Smoker System 2-Cycle & 4-Cycle MakingEngines Includes preheater pressure control valve smoker valve tubing pressure taps check valve Little Extra lete instructions Weekend MoneyMoney Back Guarantee CALL 1-912-367-0567 Visa Mastercard &/L4/IJ 1 American Ex ess CALL OR WRITEYAMERICAN MODEL PRODUCTS Inc FOR DETAILSAccePte4RT3 BOX 57BAXLEY GA31513 Become Part Time battery needs call write B&P Associates PO Box 22054 Waco TX 76702-2054 817662-5587 new electric starter battery pack Cuts cord has always tied starter power panel Discover freedom being able start plane wherever added safety less wire get caught prop charge hefty 4 Amp/hour pack will take through weekend flying power enough spare dont stop have Ni-Cads virtually size imaginable cut experimenter free design whatever takes make yours best setup field airfoil features undercamber would like lift however additional drag would detriment rate climban equally important consideration question became could gain added undercamber lift increasing drag over flat-bottom section clue came FF fraternity fundamental factor has use very thin undercambered airfoils needed determine whether drag thin undercambered airfoil would equal normal flat-bottom section whether would increase lift evaluate thinking chose reduce normal 11% thickness Davis #5 airfoil 7% As sidelight can see 10-inch chord has thickness less 3/4 inch could strength problem am happy report particular stressedskin structure has proven adequate complete range flying conditions Comparative flying thin undercambered airfoil immediately opened eyes Simply interchanging wing others produced vicious stalling tendencya strong indication lift being produced obtain satisfactory performance radical change made force arrangement Increasing tail lift removed power-on stall resulted nose-down attitude glide mode obvious section much sensitive speed changes final change produced satisfactory overall performance move CG back proper position relative new mean centerline created excellent glide mode affecting power mode So does thin undercambered section compare other airfoils gliding power-on speeds rate climb comparable Eppler 193 Davis airfoils However Eppler 176 quicker respects rate sink average conditions also similar pronounced asset quite apparent undercambered airfoil does respond light lift readily better others could due combi nation elements involved configuration However should noted airfoil allows change elements Summary After effort factor stands out Considering performance differences seen between some airfoils general performance of would acceptable Enduro flying differences seen might suit some particular need Eppler 176 windy conditions thin undercambered section light lift etc Sorry no great magic found astound Dihedral We see numerous gliders exotic Electrics apparently flying well little no dihedral objective regain lift lost normal dihedral 38 Model Aviation Associates Gives Total Flight Line FREEDOM angles used negative factor apparent need use ailerons directional control might ask whether additional weight complexity ailerons outweigh gain lift second question could whether use dihedral adequate yaw control using rudder can alleviated experience indicated some dihedral effect asset lateral stability creating flatter turns also found minimum dihedral sufficient investigation included minimum amount dihedral comparing polyhedral effect straight dihedral obtaining suitable yaw control rudder comparison base used classic polyhedral low angles used proved no shortage stability However rudder control very soft especially low speeds typical gliders Electrics Another wing low straight dihedral yielded similar yawcontrol results least RC craft dihedral angles can kept minimum no adverse results Polyhedral appeared provide no benefit hence its complexity could eliminated Yaw control rudder/fin typical size location models type initially used Under power glide mode proved usable altitude although response time slower might like minimum flight speeds might seen landing approach often wondered rudder quit working best situation far cure use full flying rudderfin pivoted tA-chord point very much like what used WW pursuit planes initial powered launch arrangement shocked slight yaw correction desireda normal application rudder yawed model complete 900 Directional control used kid gloves rest flight next flight normal amount rudder deflection cut half Since have nothing positive instanta neous yaw control under circumstances Would concept adequate flat wings place ailerons could assumed yaw control would adequate would rudder action raise dropped wing ailerons So far Ijust havent opportunity investigate Wing planforms classic FF-style wing planform especially polyhedral used long straight center panel tapered tips Such shape has always provided excellent performance basis comparisons Some time back much ado media plus positive reports modelers expounding virtues Schuemann wing planform felt worthy attention straight-dihedral wing using Schuemann parameters verbatim produced flown first indication difference Continued page 42 U 4 0AFTED 395O-AValietBlvd WALNUT CA 91789N C uJ 4 W T PE RR 0 0 F CALL OR WRITE FOR FREE BROCHURE August1993 39 QtLALIIY TrEGUTY SWICE UALrIY PITEGflTY SRviCE l2JJAtlTY IIITEGflTY SERVICE C S T FA RN ED EI 01 0 05 0 C 05 0 ii Tm SNAPPER fl/C COMBAT-STYLE SPORT MODEL FOR Gww OR ELECTRIC POWER * Kit includes illustrated usatructioce hardware pack formed canopy macbios- diecut parts made high-quality balsa plywood * May flown 05 electric power 049 11 glow engine power Parts izutnictiona both versiolsa included 5 Ofibta solid big-plane perfonuance Its small plane flies like 40$49 pts standard-size servos Wlngspan 34 inches Area 288 square inches Weight 7 ounces airframe 22 26 ounces ready fly glow powered 33 36 ounces y fly electric powered 562w Srhrork Rosd westarvitte Ohio 43051 manufactured by AEROCRAFT dutuibuted Capstone fl/C Suppliers Call 1-800-593-5250 LDM Industries Inc THE INTRODUCES.. STRONGBOXTM RECEIVER AND BAlTERY PACK PROTECTION SYSTEM STRONGBOX revolutionary new product designed toprovideboth vibration crash protection receiver battery pack TheSTRONGBOXis molded tough polypropylene plastic lined vibration absorbing foam STRONGBOX designed mount model just like servo tray included mounting hardware Measuring lflf&nOl cut-away Off lie bTI RVNGBOXTM 24 inches deep 27 inches wide 41 inches long STRONGBOX will fit 40 hrger sized models 19 ounces including foam padding mounting hardware STRONGBOX weighs about same standard size servo receiver battery pack valuable components R/C control system Give vibration crash protection need deserve Protect valuables STRONGBOX Part #8000 795 U1~vA a1 Due overwhelming response Anniversary Sale have decided permanently lower retail price entire line Ball Bearing Servo Conversion Kits way saying thanks continuing support products company Futaba S28 S38 S48 S128 S138 S148 Cirrus S28 CS1 28 CS238 & C5248 servos Kit #9600 4 pack ..$2995 Kit #9610 1 pack..$ 795 Airtronics 94102 servos Kit #9700 4 pack ..$2995 Kit #9710 1 pack..$ 795 JR 501 & 507 Focus H5300 RCD 05 Tower TS-51 Hobbico CS-SI Ace 330 servos Kit #9800 4 pack ..$2095 Kit #9810 1 pack..$595 NO-HEAT Tiuivi SOLXTENTTM Takes Hassle Out Monokote Trim Work Bonds Monokote aver Monokote beat Eliminates ugly bubbles wrinkles Completely fuel-proof easy use WiIl cause colors bleed Allows time position trim pieces Also works Ultracote Oracover Part #95004 oz Bottle 01 Upgrale 4 standard servos less cost bell bearing servo LDM Industries Ball Bearing Servo Conversion Kits will Eliminate wobble output shaft Reduce control response deadhand Reduce chance flutter hnprove control surface centering Allow use pull-pull cables Florida residents add 6 1125 sales tax VISA MASTER CARD Accepted Dealer Inquiries Welcome C 1993 LDM Industries Inc AerodynamicldeBolt Continued page 39 need move CC back sweptback tips obviously moved center lift rearward After required trim change numerous comparative flights made no outstanding difference However did appear slight increase penetration questionable increase liftno worse classic wing sure possible plus factor Another planform time tells us should acme shapes elliptical outline Schuemana planform has leading edge sharp changes direction Fundamental drag factors dictate sharp contour changes no-no respects raised another question Could Schuemana planform improved using parabolic curve remove sharp breaks seemed worth try took Schuemann layout developed parabolic curve intersected Schuemana parameter points nothing else produced pretty look birdlike wing would great able say comparative flights sensational real story have look closely observe real difference can say gains similar seen true Schuemann shape however time pronounced parabolic planform appears efficient lot small way canard final planform worthy mention because might solve nasty problem such tail-heavy design no other suitable cure consideration get center wing lift far enough back balance purposes Using KISS Keep Simple Stupid principle initial effort used typical EF-style polyhedral wing Normally planform uses equal taper tip LE TE canard put taper LE swept tips back speak first flew wing normal configuration As initial Schuemann flights center lift obviously much farther back normal After required CC trim change wing compared very closely classic wing appears possible cure tail-heavy condition sweeping wing tips aft conclude wing investigations believe low straight-dihedral parabolic Schuemann planform thin airfoil greatest efficiency results comparative flying wing planforms would very similar seen airfoils probably no planform vastly superior provided stray far established path Aerodynamic Investigations will con clude second segment will de scribe extensive investigations horizontal tails force arrangements winglets odel Aviation ARRANTY WHAT VE SELLI Factory Authorized E-Z UP Corp Dealer John Peck Leisure Products Ltd 131 RAVENWOOD RD AILLES KY 873- 1/21 order send check money order including 30O S&H LDM Industries Inc PO Box 2923% Dept 140 Tampa FL 33687-2396 Phone/Fax 813 985-5616
Edition: Model Aviation - 1993/08
Page Numbers: 36, 37, 38, 39, 42
IIEROIYNAM IC DArn NV 1GM NS INE U HAL DEBfl1 YOU ARE mainstream model activities se re never enough time what needs done get o e next action Along way see possibilities would like look needed time flies retire action unless rocking chair beckons time available investigate some ever get items thought have spent last two years investigating Some findings surprising seem worthy pass objective use basic aerodynamics find methods improving performance and/or solving problems Electrics current phase modeling make ideal vehicles research Like free flight models electric-powered Enduro designs must perform over wide speed range unlike free flight excess power available simply blast away Perfonnance easily observed differences quite apparent flight Unfortunately have sophisticated wind tunnels lot can learned comparative flying Successive flights can compared using different configurations flights made results have real vehicle still used basic Enduro design modified wings tails can interchanged force arrangements can altered high-performance design easily climbs out-of-sight much less minute glide mode also match best Thus flight change good bad easily observed comparisons simple comparative investigations involved wing airfoils wing planforms dihedral horizontal tail airfoils sizes/force arrangements center gravity CC location rudder responsiveness winglets None investigations developedfully areas uncovered indicated further development would warranted short positive results seen pointing improved performance give report continuity will begin wing since heart aircraft follow factors assure wing flies maximum efficiency should noted some factors investigated force arrangement altered compensate difference forces seen case done until appeared maximum performance achieved concept Airfoils compare airfoils obviously need separate wing eacha formidable task involved answer 36 Model Aviation ing done several high-performance electric Enduro models wings tails interchangeable EPPLER 193 EPPLER 176 DAVIS DAVIS Diagram Various wing planforms comparatively flown Schuemann version far right has winglets added choose four proven airfoils would indicate what expect anything similar nature started Eppler 193 widely used electricpowered Enduros Performance excellent formed basis comparison did appear bit touchy longitudinal stability controlled judicious adjustments force arrangement second airfoil investigated Eppler 176 major difference between two airfoils 176 about 20% thinner 193 wing creating major aircraft drag thinner airfoil should result less drag higher flying speed questions whether higher flying speed would allow thinner section equal lift thicker whether rate climb would greater Comparative flying indicated higher flying speed gave increased rate climb higher speed proved distinct advantage thermal hunting windy conditions slowed down match 193s flying speed higher rate sink obvious speed increased liking 176 sink rate became comparable Bottom line 176 needs fly faster many modeling years numerous types models have found performance Davis airfoils outstanding provided excellent lift stability plus low drag strong desire compare Eppler Davis sections however Davis airfoils familiar included undercamber associated drag could expected Fortunately found flat-bottom version John Malkin s fine airfoil book Davis section identical thickness Eppler 193 comparative flying immediately noticed Davis 193 wings could readily interchanged no adjustments required found Davis tolerant CG changes Eppler effect its stability remained intact farther-aft CG aft CG allowed use tail lift equates total lift added tail lift also asset controlling power Over long haul comparative flying three airfoils Davis did seem have advantage under normal flying conditions However edge would have go Eppler 176 windy weather last airfoil tested wonder what would happen investigations Theory tells us can expect lift August1993 37 POLYHEDRAL POLYHEDRAL STRAIGHT SCHUEMANN PARABOLIC SCHUEMANN Diagram 2 full flying rudder gave positive yaw control speeds long strip hinge attaches fuselage Part II author will investigate horizontal tail areas airfoilsother elements comparative flying CENTURY MODELS INC 8 Martha Ct8305 Regency Woods Way Sumter SC 29150Louisville KY 40220 803 775-6491502 491-4114 RETRACT SELECTOR SPEED CONTROL VALVE Four Infinite Adjustment Screws 2 Up 2 Down Compatible air system Dim 3/8 s1 s 1-114$2495 WI 15 oz Semi & Deluxe Ducted Fan Jet Kits Eposy fiberglass fuselage canopy foam wings plans instructions Intake/Eshaust System euc F-ba F-100 Hun basic kit $18999 1/8 Scale 50 Removable Wings Length 63 Sport Hawk MK U basic kit $18988 Easy build Removable wing th 59 F-105 Thunderchief basic kit $23900 Length 73" 77-91 Engine heater Hole F4 Phantom basic kit $59900 NEW 1/7 Scale Twin Engine Aileron/Spoiler Config Length 90 vable 61 Wings E flaps Deluse kit DC wood I/B pylons CP kit plus morel Landing gear tires brakes available COMPARE OUR RETRACTS TO THEIRS Stainless Struts cut FREE Stainless Torque Links Different strut configurations 1 Year Limited Warranty GIANT MAIN RETRACTS STANDARD OR 900 ROTATI 30-50 lb aircraft 2 sets 1 Standard 9Q0 minutes 700 11 QO retract angle Over-center lock down Nose gear available $27500 pair Wt 15 lbs Complete Air System Axle Installed Parts Service 30 Day Retundf r15 SCALE MAIN RETRACTS STANDARD OR 900 ROTATE Fits PICA Skys P-Si 1/5 Yellow NC Ziroli Bud Nosen plus Choice 91 Plyon Winners Handles 20-25 lb aircraft 540 970 retract angle Positive lock up lock down Optional wire struts Nose gear available $19900 pair WI 22 oz NEW 1/5 SCALE P-51 & SPITFIRE products proudly MADE IN THE USA AILABIENew 2-Cvcle 40 &un Aluminum Airplane Coming Soon Smoker Preheaters Are Twice Enjoy Flying As Effective As Head Coils Funflys & Complete Smoker System 2-Cycle & 4-Cycle MakingEngines Includes preheater pressure control valve smoker valve tubing pressure taps check valve Little Extra lete instructions Weekend MoneyMoney Back Guarantee CALL 1-912-367-0567 Visa Mastercard &/L4/IJ 1 American Ex ess CALL OR WRITEYAMERICAN MODEL PRODUCTS Inc FOR DETAILSAccePte4RT3 BOX 57BAXLEY GA31513 Become Part Time battery needs call write B&P Associates PO Box 22054 Waco TX 76702-2054 817662-5587 new electric starter battery pack Cuts cord has always tied starter power panel Discover freedom being able start plane wherever added safety less wire get caught prop charge hefty 4 Amp/hour pack will take through weekend flying power enough spare dont stop have Ni-Cads virtually size imaginable cut experimenter free design whatever takes make yours best setup field airfoil features undercamber would like lift however additional drag would detriment rate climban equally important consideration question became could gain added undercamber lift increasing drag over flat-bottom section clue came FF fraternity fundamental factor has use very thin undercambered airfoils needed determine whether drag thin undercambered airfoil would equal normal flat-bottom section whether would increase lift evaluate thinking chose reduce normal 11% thickness Davis #5 airfoil 7% As sidelight can see 10-inch chord has thickness less 3/4 inch could strength problem am happy report particular stressedskin structure has proven adequate complete range flying conditions Comparative flying thin undercambered airfoil immediately opened eyes Simply interchanging wing others produced vicious stalling tendencya strong indication lift being produced obtain satisfactory performance radical change made force arrangement Increasing tail lift removed power-on stall resulted nose-down attitude glide mode obvious section much sensitive speed changes final change produced satisfactory overall performance move CG back proper position relative new mean centerline created excellent glide mode affecting power mode So does thin undercambered section compare other airfoils gliding power-on speeds rate climb comparable Eppler 193 Davis airfoils However Eppler 176 quicker respects rate sink average conditions also similar pronounced asset quite apparent undercambered airfoil does respond light lift readily better others could due combi nation elements involved configuration However should noted airfoil allows change elements Summary After effort factor stands out Considering performance differences seen between some airfoils general performance of would acceptable Enduro flying differences seen might suit some particular need Eppler 176 windy conditions thin undercambered section light lift etc Sorry no great magic found astound Dihedral We see numerous gliders exotic Electrics apparently flying well little no dihedral objective regain lift lost normal dihedral 38 Model Aviation Associates Gives Total Flight Line FREEDOM angles used negative factor apparent need use ailerons directional control might ask whether additional weight complexity ailerons outweigh gain lift second question could whether use dihedral adequate yaw control using rudder can alleviated experience indicated some dihedral effect asset lateral stability creating flatter turns also found minimum dihedral sufficient investigation included minimum amount dihedral comparing polyhedral effect straight dihedral obtaining suitable yaw control rudder comparison base used classic polyhedral low angles used proved no shortage stability However rudder control very soft especially low speeds typical gliders Electrics Another wing low straight dihedral yielded similar yawcontrol results least RC craft dihedral angles can kept minimum no adverse results Polyhedral appeared provide no benefit hence its complexity could eliminated Yaw control rudder/fin typical size location models type initially used Under power glide mode proved usable altitude although response time slower might like minimum flight speeds might seen landing approach often wondered rudder quit working best situation far cure use full flying rudderfin pivoted tA-chord point very much like what used WW pursuit planes initial powered launch arrangement shocked slight yaw correction desireda normal application rudder yawed model complete 900 Directional control used kid gloves rest flight next flight normal amount rudder deflection cut half Since have nothing positive instanta neous yaw control under circumstances Would concept adequate flat wings place ailerons could assumed yaw control would adequate would rudder action raise dropped wing ailerons So far Ijust havent opportunity investigate Wing planforms classic FF-style wing planform especially polyhedral used long straight center panel tapered tips Such shape has always provided excellent performance basis comparisons Some time back much ado media plus positive reports modelers expounding virtues Schuemann wing planform felt worthy attention straight-dihedral wing using Schuemann parameters verbatim produced flown first indication difference Continued page 42 U 4 0AFTED 395O-AValietBlvd WALNUT CA 91789N C uJ 4 W T PE RR 0 0 F CALL OR WRITE FOR FREE BROCHURE August1993 39 QtLALIIY TrEGUTY SWICE UALrIY PITEGflTY SRviCE l2JJAtlTY IIITEGflTY SERVICE C S T FA RN ED EI 01 0 05 0 C 05 0 ii Tm SNAPPER fl/C COMBAT-STYLE SPORT MODEL FOR Gww OR ELECTRIC POWER * Kit includes illustrated usatructioce hardware pack formed canopy macbios- diecut parts made high-quality balsa plywood * May flown 05 electric power 049 11 glow engine power Parts izutnictiona both versiolsa included 5 Ofibta solid big-plane perfonuance Its small plane flies like 40$49 pts standard-size servos Wlngspan 34 inches Area 288 square inches Weight 7 ounces airframe 22 26 ounces ready fly glow powered 33 36 ounces y fly electric powered 562w Srhrork Rosd westarvitte Ohio 43051 manufactured by AEROCRAFT dutuibuted Capstone fl/C Suppliers Call 1-800-593-5250 LDM Industries Inc THE INTRODUCES.. STRONGBOXTM RECEIVER AND BAlTERY PACK PROTECTION SYSTEM STRONGBOX revolutionary new product designed toprovideboth vibration crash protection receiver battery pack TheSTRONGBOXis molded tough polypropylene plastic lined vibration absorbing foam STRONGBOX designed mount model just like servo tray included mounting hardware Measuring lflf&nOl cut-away Off lie bTI RVNGBOXTM 24 inches deep 27 inches wide 41 inches long STRONGBOX will fit 40 hrger sized models 19 ounces including foam padding mounting hardware STRONGBOX weighs about same standard size servo receiver battery pack valuable components R/C control system Give vibration crash protection need deserve Protect valuables STRONGBOX Part #8000 795 U1~vA a1 Due overwhelming response Anniversary Sale have decided permanently lower retail price entire line Ball Bearing Servo Conversion Kits way saying thanks continuing support products company Futaba S28 S38 S48 S128 S138 S148 Cirrus S28 CS1 28 CS238 & C5248 servos Kit #9600 4 pack ..$2995 Kit #9610 1 pack..$ 795 Airtronics 94102 servos Kit #9700 4 pack ..$2995 Kit #9710 1 pack..$ 795 JR 501 & 507 Focus H5300 RCD 05 Tower TS-51 Hobbico CS-SI Ace 330 servos Kit #9800 4 pack ..$2095 Kit #9810 1 pack..$595 NO-HEAT Tiuivi SOLXTENTTM Takes Hassle Out Monokote Trim Work Bonds Monokote aver Monokote beat Eliminates ugly bubbles wrinkles Completely fuel-proof easy use WiIl cause colors bleed Allows time position trim pieces Also works Ultracote Oracover Part #95004 oz Bottle 01 Upgrale 4 standard servos less cost bell bearing servo LDM Industries Ball Bearing Servo Conversion Kits will Eliminate wobble output shaft Reduce control response deadhand Reduce chance flutter hnprove control surface centering Allow use pull-pull cables Florida residents add 6 1125 sales tax VISA MASTER CARD Accepted Dealer Inquiries Welcome C 1993 LDM Industries Inc AerodynamicldeBolt Continued page 39 need move CC back sweptback tips obviously moved center lift rearward After required trim change numerous comparative flights made no outstanding difference However did appear slight increase penetration questionable increase liftno worse classic wing sure possible plus factor Another planform time tells us should acme shapes elliptical outline Schuemana planform has leading edge sharp changes direction Fundamental drag factors dictate sharp contour changes no-no respects raised another question Could Schuemana planform improved using parabolic curve remove sharp breaks seemed worth try took Schuemann layout developed parabolic curve intersected Schuemana parameter points nothing else produced pretty look birdlike wing would great able say comparative flights sensational real story have look closely observe real difference can say gains similar seen true Schuemann shape however time pronounced parabolic planform appears efficient lot small way canard final planform worthy mention because might solve nasty problem such tail-heavy design no other suitable cure consideration get center wing lift far enough back balance purposes Using KISS Keep Simple Stupid principle initial effort used typical EF-style polyhedral wing Normally planform uses equal taper tip LE TE canard put taper LE swept tips back speak first flew wing normal configuration As initial Schuemann flights center lift obviously much farther back normal After required CC trim change wing compared very closely classic wing appears possible cure tail-heavy condition sweeping wing tips aft conclude wing investigations believe low straight-dihedral parabolic Schuemann planform thin airfoil greatest efficiency results comparative flying wing planforms would very similar seen airfoils probably no planform vastly superior provided stray far established path Aerodynamic Investigations will con clude second segment will de scribe extensive investigations horizontal tails force arrangements winglets odel Aviation ARRANTY WHAT VE SELLI Factory Authorized E-Z UP Corp Dealer John Peck Leisure Products Ltd 131 RAVENWOOD RD AILLES KY 873- 1/21 order send check money order including 30O S&H LDM Industries Inc PO Box 2923% Dept 140 Tampa FL 33687-2396 Phone/Fax 813 985-5616
Edition: Model Aviation - 1993/08
Page Numbers: 36, 37, 38, 39, 42
IIEROIYNAM IC DArn NV 1GM NS INE U HAL DEBfl1 YOU ARE mainstream model activities se re never enough time what needs done get o e next action Along way see possibilities would like look needed time flies retire action unless rocking chair beckons time available investigate some ever get items thought have spent last two years investigating Some findings surprising seem worthy pass objective use basic aerodynamics find methods improving performance and/or solving problems Electrics current phase modeling make ideal vehicles research Like free flight models electric-powered Enduro designs must perform over wide speed range unlike free flight excess power available simply blast away Perfonnance easily observed differences quite apparent flight Unfortunately have sophisticated wind tunnels lot can learned comparative flying Successive flights can compared using different configurations flights made results have real vehicle still used basic Enduro design modified wings tails can interchanged force arrangements can altered high-performance design easily climbs out-of-sight much less minute glide mode also match best Thus flight change good bad easily observed comparisons simple comparative investigations involved wing airfoils wing planforms dihedral horizontal tail airfoils sizes/force arrangements center gravity CC location rudder responsiveness winglets None investigations developedfully areas uncovered indicated further development would warranted short positive results seen pointing improved performance give report continuity will begin wing since heart aircraft follow factors assure wing flies maximum efficiency should noted some factors investigated force arrangement altered compensate difference forces seen case done until appeared maximum performance achieved concept Airfoils compare airfoils obviously need separate wing eacha formidable task involved answer 36 Model Aviation ing done several high-performance electric Enduro models wings tails interchangeable EPPLER 193 EPPLER 176 DAVIS DAVIS Diagram Various wing planforms comparatively flown Schuemann version far right has winglets added choose four proven airfoils would indicate what expect anything similar nature started Eppler 193 widely used electricpowered Enduros Performance excellent formed basis comparison did appear bit touchy longitudinal stability controlled judicious adjustments force arrangement second airfoil investigated Eppler 176 major difference between two airfoils 176 about 20% thinner 193 wing creating major aircraft drag thinner airfoil should result less drag higher flying speed questions whether higher flying speed would allow thinner section equal lift thicker whether rate climb would greater Comparative flying indicated higher flying speed gave increased rate climb higher speed proved distinct advantage thermal hunting windy conditions slowed down match 193s flying speed higher rate sink obvious speed increased liking 176 sink rate became comparable Bottom line 176 needs fly faster many modeling years numerous types models have found performance Davis airfoils outstanding provided excellent lift stability plus low drag strong desire compare Eppler Davis sections however Davis airfoils familiar included undercamber associated drag could expected Fortunately found flat-bottom version John Malkin s fine airfoil book Davis section identical thickness Eppler 193 comparative flying immediately noticed Davis 193 wings could readily interchanged no adjustments required found Davis tolerant CG changes Eppler effect its stability remained intact farther-aft CG aft CG allowed use tail lift equates total lift added tail lift also asset controlling power Over long haul comparative flying three airfoils Davis did seem have advantage under normal flying conditions However edge would have go Eppler 176 windy weather last airfoil tested wonder what would happen investigations Theory tells us can expect lift August1993 37 POLYHEDRAL POLYHEDRAL STRAIGHT SCHUEMANN PARABOLIC SCHUEMANN Diagram 2 full flying rudder gave positive yaw control speeds long strip hinge attaches fuselage Part II author will investigate horizontal tail areas airfoilsother elements comparative flying CENTURY MODELS INC 8 Martha Ct8305 Regency Woods Way Sumter SC 29150Louisville KY 40220 803 775-6491502 491-4114 RETRACT SELECTOR SPEED CONTROL VALVE Four Infinite Adjustment Screws 2 Up 2 Down Compatible air system Dim 3/8 s1 s 1-114$2495 WI 15 oz Semi & Deluxe Ducted Fan Jet Kits Eposy fiberglass fuselage canopy foam wings plans instructions Intake/Eshaust System euc F-ba F-100 Hun basic kit $18999 1/8 Scale 50 Removable Wings Length 63 Sport Hawk MK U basic kit $18988 Easy build Removable wing th 59 F-105 Thunderchief basic kit $23900 Length 73" 77-91 Engine heater Hole F4 Phantom basic kit $59900 NEW 1/7 Scale Twin Engine Aileron/Spoiler Config Length 90 vable 61 Wings E flaps Deluse kit DC wood I/B pylons CP kit plus morel Landing gear tires brakes available COMPARE OUR RETRACTS TO THEIRS Stainless Struts cut FREE Stainless Torque Links Different strut configurations 1 Year Limited Warranty GIANT MAIN RETRACTS STANDARD OR 900 ROTATI 30-50 lb aircraft 2 sets 1 Standard 9Q0 minutes 700 11 QO retract angle Over-center lock down Nose gear available $27500 pair Wt 15 lbs Complete Air System Axle Installed Parts Service 30 Day Retundf r15 SCALE MAIN RETRACTS STANDARD OR 900 ROTATE Fits PICA Skys P-Si 1/5 Yellow NC Ziroli Bud Nosen plus Choice 91 Plyon Winners Handles 20-25 lb aircraft 540 970 retract angle Positive lock up lock down Optional wire struts Nose gear available $19900 pair WI 22 oz NEW 1/5 SCALE P-51 & SPITFIRE products proudly MADE IN THE USA AILABIENew 2-Cvcle 40 &un Aluminum Airplane Coming Soon Smoker Preheaters Are Twice Enjoy Flying As Effective As Head Coils Funflys & Complete Smoker System 2-Cycle & 4-Cycle MakingEngines Includes preheater pressure control valve smoker valve tubing pressure taps check valve Little Extra lete instructions Weekend MoneyMoney Back Guarantee CALL 1-912-367-0567 Visa Mastercard &/L4/IJ 1 American Ex ess CALL OR WRITEYAMERICAN MODEL PRODUCTS Inc FOR DETAILSAccePte4RT3 BOX 57BAXLEY GA31513 Become Part Time battery needs call write B&P Associates PO Box 22054 Waco TX 76702-2054 817662-5587 new electric starter battery pack Cuts cord has always tied starter power panel Discover freedom being able start plane wherever added safety less wire get caught prop charge hefty 4 Amp/hour pack will take through weekend flying power enough spare dont stop have Ni-Cads virtually size imaginable cut experimenter free design whatever takes make yours best setup field airfoil features undercamber would like lift however additional drag would detriment rate climban equally important consideration question became could gain added undercamber lift increasing drag over flat-bottom section clue came FF fraternity fundamental factor has use very thin undercambered airfoils needed determine whether drag thin undercambered airfoil would equal normal flat-bottom section whether would increase lift evaluate thinking chose reduce normal 11% thickness Davis #5 airfoil 7% As sidelight can see 10-inch chord has thickness less 3/4 inch could strength problem am happy report particular stressedskin structure has proven adequate complete range flying conditions Comparative flying thin undercambered airfoil immediately opened eyes Simply interchanging wing others produced vicious stalling tendencya strong indication lift being produced obtain satisfactory performance radical change made force arrangement Increasing tail lift removed power-on stall resulted nose-down attitude glide mode obvious section much sensitive speed changes final change produced satisfactory overall performance move CG back proper position relative new mean centerline created excellent glide mode affecting power mode So does thin undercambered section compare other airfoils gliding power-on speeds rate climb comparable Eppler 193 Davis airfoils However Eppler 176 quicker respects rate sink average conditions also similar pronounced asset quite apparent undercambered airfoil does respond light lift readily better others could due combi nation elements involved configuration However should noted airfoil allows change elements Summary After effort factor stands out Considering performance differences seen between some airfoils general performance of would acceptable Enduro flying differences seen might suit some particular need Eppler 176 windy conditions thin undercambered section light lift etc Sorry no great magic found astound Dihedral We see numerous gliders exotic Electrics apparently flying well little no dihedral objective regain lift lost normal dihedral 38 Model Aviation Associates Gives Total Flight Line FREEDOM angles used negative factor apparent need use ailerons directional control might ask whether additional weight complexity ailerons outweigh gain lift second question could whether use dihedral adequate yaw control using rudder can alleviated experience indicated some dihedral effect asset lateral stability creating flatter turns also found minimum dihedral sufficient investigation included minimum amount dihedral comparing polyhedral effect straight dihedral obtaining suitable yaw control rudder comparison base used classic polyhedral low angles used proved no shortage stability However rudder control very soft especially low speeds typical gliders Electrics Another wing low straight dihedral yielded similar yawcontrol results least RC craft dihedral angles can kept minimum no adverse results Polyhedral appeared provide no benefit hence its complexity could eliminated Yaw control rudder/fin typical size location models type initially used Under power glide mode proved usable altitude although response time slower might like minimum flight speeds might seen landing approach often wondered rudder quit working best situation far cure use full flying rudderfin pivoted tA-chord point very much like what used WW pursuit planes initial powered launch arrangement shocked slight yaw correction desireda normal application rudder yawed model complete 900 Directional control used kid gloves rest flight next flight normal amount rudder deflection cut half Since have nothing positive instanta neous yaw control under circumstances Would concept adequate flat wings place ailerons could assumed yaw control would adequate would rudder action raise dropped wing ailerons So far Ijust havent opportunity investigate Wing planforms classic FF-style wing planform especially polyhedral used long straight center panel tapered tips Such shape has always provided excellent performance basis comparisons Some time back much ado media plus positive reports modelers expounding virtues Schuemann wing planform felt worthy attention straight-dihedral wing using Schuemann parameters verbatim produced flown first indication difference Continued page 42 U 4 0AFTED 395O-AValietBlvd WALNUT CA 91789N C uJ 4 W T PE RR 0 0 F CALL OR WRITE FOR FREE BROCHURE August1993 39 QtLALIIY TrEGUTY SWICE UALrIY PITEGflTY SRviCE l2JJAtlTY IIITEGflTY SERVICE C S T FA RN ED EI 01 0 05 0 C 05 0 ii Tm SNAPPER fl/C COMBAT-STYLE SPORT MODEL FOR Gww OR ELECTRIC POWER * Kit includes illustrated usatructioce hardware pack formed canopy macbios- diecut parts made high-quality balsa plywood * May flown 05 electric power 049 11 glow engine power Parts izutnictiona both versiolsa included 5 Ofibta solid big-plane perfonuance Its small plane flies like 40$49 pts standard-size servos Wlngspan 34 inches Area 288 square inches Weight 7 ounces airframe 22 26 ounces ready fly glow powered 33 36 ounces y fly electric powered 562w Srhrork Rosd westarvitte Ohio 43051 manufactured by AEROCRAFT dutuibuted Capstone fl/C Suppliers Call 1-800-593-5250 LDM Industries Inc THE INTRODUCES.. STRONGBOXTM RECEIVER AND BAlTERY PACK PROTECTION SYSTEM STRONGBOX revolutionary new product designed toprovideboth vibration crash protection receiver battery pack TheSTRONGBOXis molded tough polypropylene plastic lined vibration absorbing foam STRONGBOX designed mount model just like servo tray included mounting hardware Measuring lflf&nOl cut-away Off lie bTI RVNGBOXTM 24 inches deep 27 inches wide 41 inches long STRONGBOX will fit 40 hrger sized models 19 ounces including foam padding mounting hardware STRONGBOX weighs about same standard size servo receiver battery pack valuable components R/C control system Give vibration crash protection need deserve Protect valuables STRONGBOX Part #8000 795 U1~vA a1 Due overwhelming response Anniversary Sale have decided permanently lower retail price entire line Ball Bearing Servo Conversion Kits way saying thanks continuing support products company Futaba S28 S38 S48 S128 S138 S148 Cirrus S28 CS1 28 CS238 & C5248 servos Kit #9600 4 pack ..$2995 Kit #9610 1 pack..$ 795 Airtronics 94102 servos Kit #9700 4 pack ..$2995 Kit #9710 1 pack..$ 795 JR 501 & 507 Focus H5300 RCD 05 Tower TS-51 Hobbico CS-SI Ace 330 servos Kit #9800 4 pack ..$2095 Kit #9810 1 pack..$595 NO-HEAT Tiuivi SOLXTENTTM Takes Hassle Out Monokote Trim Work Bonds Monokote aver Monokote beat Eliminates ugly bubbles wrinkles Completely fuel-proof easy use WiIl cause colors bleed Allows time position trim pieces Also works Ultracote Oracover Part #95004 oz Bottle 01 Upgrale 4 standard servos less cost bell bearing servo LDM Industries Ball Bearing Servo Conversion Kits will Eliminate wobble output shaft Reduce control response deadhand Reduce chance flutter hnprove control surface centering Allow use pull-pull cables Florida residents add 6 1125 sales tax VISA MASTER CARD Accepted Dealer Inquiries Welcome C 1993 LDM Industries Inc AerodynamicldeBolt Continued page 39 need move CC back sweptback tips obviously moved center lift rearward After required trim change numerous comparative flights made no outstanding difference However did appear slight increase penetration questionable increase liftno worse classic wing sure possible plus factor Another planform time tells us should acme shapes elliptical outline Schuemana planform has leading edge sharp changes direction Fundamental drag factors dictate sharp contour changes no-no respects raised another question Could Schuemana planform improved using parabolic curve remove sharp breaks seemed worth try took Schuemann layout developed parabolic curve intersected Schuemana parameter points nothing else produced pretty look birdlike wing would great able say comparative flights sensational real story have look closely observe real difference can say gains similar seen true Schuemann shape however time pronounced parabolic planform appears efficient lot small way canard final planform worthy mention because might solve nasty problem such tail-heavy design no other suitable cure consideration get center wing lift far enough back balance purposes Using KISS Keep Simple Stupid principle initial effort used typical EF-style polyhedral wing Normally planform uses equal taper tip LE TE canard put taper LE swept tips back speak first flew wing normal configuration As initial Schuemann flights center lift obviously much farther back normal After required CC trim change wing compared very closely classic wing appears possible cure tail-heavy condition sweeping wing tips aft conclude wing investigations believe low straight-dihedral parabolic Schuemann planform thin airfoil greatest efficiency results comparative flying wing planforms would very similar seen airfoils probably no planform vastly superior provided stray far established path Aerodynamic Investigations will con clude second segment will de scribe extensive investigations horizontal tails force arrangements winglets odel Aviation ARRANTY WHAT VE SELLI Factory Authorized E-Z UP Corp Dealer John Peck Leisure Products Ltd 131 RAVENWOOD RD AILLES KY 873- 1/21 order send check money order including 30O S&H LDM Industries Inc PO Box 2923% Dept 140 Tampa FL 33687-2396 Phone/Fax 813 985-5616