LET pass few hints before getting meat article first two involve adhe sives Ive hobby long enough can re member everyone used Ambroid didnt smell great water-soluble glues like Tite bond Wilhold big improvements cyanoacrylates like Hot Stuff Jet Zap etc same true epoxies con tact cements work great own way some adhesives work better others specific applications book difficult applications adhering servo rails sides polyester epoxy fiberglass fuselages always worried about servo rails pop ping loose fuselage sides hard land ings violent maneuvers fears justi fied sometimes did pop loose used epoxies cyanoacrylates nothing satis factory tried Wilhold R/C 56 adhesive works has combination ot flexibility tenacity makes ideal attaching wood fiberglass gave some pretty severe tests including airplane crash couldnt get turn rails loose fuselage sides R/C 56 white bottle dries clear easy clean up wet rag still wet nothing seems touch dry also use install bulkheads fiberglass fuse lages install hinges attach canopies fuselage works great ever worry wing bolts will pull threads right Out plywood screw too discovered can trickle little cyanoacrylate down threads plywood make times stronger After applying adhesive allow ing set usually rethread hole remove hardened wood fuzz clean up threads will break nylon bolts before pulling out Figure 3 5/2 Equation 1 Equation 2 03 R2RTT2 _ B R-i-T\ 2 77 7 7 7 7 7 7 -4 R R AC Ri T Equation 3 Figure 2 IEquation 4 Equation 5 lvA xl IX21I/1 / X3 / T1 R2 AC C2AC I/ \T2R3 3 T3 I/ / I/ Figure 4 c C1S1C2S2-i-C3S3 Si 53 CG S1S3 C X1S1X2S2X3S3 Si S3 Author Ron Van Putte explains find proper location models center-of-gravity has odd-shaped wing An explanation use figures formulas given months column dont have engineer scientist put method use 50 Model Aviation Radio Control Sport Aerobatics Ron Van Putte I Sleepy Oaks Rd Ft Walton Beach FL 32548 R Figure 1 N T t t / T R 4 threads after treatment last hint involves sanding like goodlooking finish requires lot sanding After applying primer sand After base coat sand Afier subsequent coats sand As said lot sanding Sanding tough work dust goes especially primer coat So re sorted alcohol No drinking welling surface sanded Actually use rubbing alcohol surface Im sanding alcohol must used wet-or-dry sandpaper holds down sanding dust really shortens sand ing time use plastic laboratory bottle squirt some alcohol surface sand until just before surface dries up rub off slimy mess soft cloth think alco hol partially dissolves finish newly painted surfaces epoxies thats what makes sanding go much faster Try meat months column giving method used determine aerodynamic center wings irregularly shaped planforms explaining use information figure out center-of-gravity air plane should Ive gotten enough letters modelers asking think theres enough general interest warrant following discussion key information makes things work calculations locating aerody namic center wing can broken pieces piece contributes its part total aerodynamic inputs can calculated add ing up effects of parts limitations theory because edge effects places pieces join wing has reasonably high aspect ratio pect ratio approximately ratio wing span chord theory works out very well airfoil section has aerodynamic center aerodynamic center place airfoil pitching moment produced air flowing over airfoil independent airfoils angle attack seems unlikely such location exists does airfoils aerodynamic center lo cated point 25% chord back leading edge airfoil wont show inte gral calculus equation determining loca tion aerodynamic center because Model Aviation staff has fits trying get such equations typesetting machine Suffice say aerodynamic center can calcu lated 25% point mean aerody namic chord mean aerodynamic chord also called MAC Sometimes fictitious chord rec tangular wing would produce same forces moments actual wing wing like Figure 1 mean aerodynamic chord calculated Equation 1 Figure 1 also shows what wings mean aero dynamic chord looks like located wing Youll note its mid dle wing mean average chord Theres another way determine aerody namic center just accurate equa tion done properly accurately may have seen several versions geometric tech nique shown Figure 2 intersection two lines drawn diagonally across wing midpoint wing mean aerodynamic chord aerodynamic center located 25% point mean aerodynamic chord Now what about weird-looking wing shown Figure 3 first use either equa tion geometric technique determine Continued page 156 Sport Aerobatic 55 span 51 length 4 channel 14Y2 t wing Symetrical Airfoil Engine 45- 602cy 60- 804 SAVE YOUR FIELD P L2 mutt s ow coet easy nets ghr gI sournct ectuc og mutt e w U no p 0COCC perle ty t s anawe oAMArTtu Se uesuggeetoneandsavngfyng ede Meets AMA muffler rule suggestions 3 10 decIbels quIeter stock muffler No power loss poesible 300-500 RPM Improves engtne Idle s better fuel evunuany Cestly ettached moat 25-108 stoolt mufflers Heat arid Corrosion resistant BlaCk E coat finIsh No speotat adapters requIred WeIghs 35 ozs SN UF-LERTM pso ASP aPsr SNvA Pex P vlNE KAB OS MAX MUFFLER POYAL YS SUP5 FlOPS mutters Patented Kit includes rolled plans cut sanded pans formed landing gear wheel axels steerable tail wheel bracket push rod set other basic hardware 1 SNUF-LER mufflers JTEC IN-COWL mufflers anavaaanrn item F, 29 65 JTEc nvat5es 2496JThcwvvevu cat,, us JT 652 Fe elI 75 nfl jrtc nudfles 2495Thu SNUP-lSP Mutnier cats u5Cd220 rato mwsso JT653 FoeIlOIANTaiaeJTFCnxSSIee 2495 scale ar rattwd JTSC N-COWLrusor5vomanu200 ' lduede ZENOASI supte TIdeS OPS -nutflers elm eta b tu025 St 00 Tow 020 MAXI 30 sULLY SACHS DOLMASSI oTuct ye so,, 05 muffler canom tte tuSSIag84Tn020 N cwo2 N Ft canneeterl ta JTSC muffler59555 euwSan na 20th neearerw tubing Par socearanes teas remaved 50cr Syind -at-- a-- IS net available atysar SaSSy shw asoce oleserte wreediate eSipereet eseek MO Va MC ecoo 5Tuitt accented Add *25090 ups saw So COO 6%Fee ossemonue School St DelCA 94014 ealeetaufo CaIiSooie teeida0t5ate vttt CAnulec14151756-34004 December 1989 51 WARNING Dont fooled Johnny Come Latelys Soft Mounting good airplane effective soft mount used ones use accelerometers ensure LOWEST transmitted vibration backed years proven contest performance UNIVERSAL 11 2cyd engines 20 TO 61EASY ro USE. EVERYTHING INCLUDED FOR MOUNTINGI Available better Hobby Dealers order direct add $175 shipping MADE IN USA manufacturer DISC-LOCK & HUSH rOAM - dealer distributorships invited PERFORMANCE PRODUCTS UALIMITED 7093 E Dodge Rd Ms Morris Ml 48458 e Orders 1313631-4894 /MC accep Kleen Sweep 87995 5500 P & H Check M 0 cyV sa MC Other Kits Avail Wr te free cat 317 525-9074 Crenshaw AeroRR 1 Box 121 ManIlla IN 46150 GATOR RIC PRODUCTS DELUX ALL BALSA KIT An new Tiger Tail 120 four strokes piped 60 two strokes beautiful performer competition just showing offI balsa kit machined wood parts complete lsardware package includes plug-in djustable stab parts new wing mounts Wing Span- 72 inWing Ara 860 sq Complete Delux KitSI 5995 TRANSMITTER CASE An inexpensive rugged molded case protect expensive transmitter both two stick single stick transmitters Black leather grain aluminum trim locking clasp SI 995 MV-I TYPHOON New F3A competition Big beautiful flyer balsa construction plug-in wings 120 four stroke 60 two stroke power Plans-two sheets S 1495 Fiberglass cowl Si 595 Clear butyrate canopy. 5 995 OTHER PLANS Tiger Tail 4S-two sheets 120 four strokesS 1495 TAR baby 120 four strokes51195 Alley Kat 40 size trainer sportS 895 Gator Flea 40 size sport5 895 Bobcat 40 size sportS 895 feather Ilte glass cloth 7 ozsq yd est weave Fastest Filling test Finished Weight Big 3 Sq Yard Pkg Oetailed Instructions- $895 Include $2 SOlItem UPS esidents Add 6% Sales Tax GATOR RIC PRODUCTS 3713 Pompano Dr acola FL 32514 4768639 Letters Editor Continued page 12 Ken opened hobby shop Burk & Company Department Store after World War II worked him full-time year until started college After worked part-time until completing college Milton H Fanning Nashville TN Safety/Preston Continued page 22 some MonoKote repairs moral tale wise keep small extinguisher field box As alter native may possible smother fire towel rag blanket Cub Yellow engine cowling first RC model powered Cox 09 began turn first orange brown able smother fire wrap ping rag around front model Have safe month Keytwo/Randoiph Continued page 30 der everything place range check equipmentand its time fly Flying has wide performance en velope compared Paskey Keytwo basically quite gentle flier Whether upright inverted stall shows abso lutely no tendency snap fact model balanced correctly its very diffi cult make snap snaps bag move center-of-gravity aft about /2 increase elevator throw rate /16 up down movement trailing edge aile rons about right comfortable flying Landings can made nose-high slow full aileron control way touch down problem knife-edge flight first airplane persistently climbed half-loop until learned nose stayed up just little rudder Once Id mastered technique knife-edge loops included Keytwos repertoire tricks what did Eddie Williams have say about latest re-creation see youve built another Paskey said unsung maestro drunken pilot routine Its about time Play again Eddie Radio Technique/Myers Continued page 34 Failsafe Flight System small 15 sq light less ounce inexpensive has very low operating current 70 mA works no doubt nine-volt transistor radio batteries expensive about $250 Duracells live will last long time some chance will get care less let run down some critical time unit meets its claims follow admonition use fresh batteries check servo speed during preflight inspection careless youll probably crash some other reason anyway Failsafe Flight System @ $3995 list T&D Flight Systems PO Box 1782 Staten Island NY 10314 additional information call Alex Kronfeld l-7t8/984-9121 Propeller Noise Continued page 42 cause poor community relations Much cure will depend upon education Modelers need understand nature problem order properly utilize solu tions article has introduced propel ler noise problem provided some neces sary background Subsequent articles will explain test results greater detail describe what modeler can achieve better aircraft performance less noise RC Soaring/Blakeslee Continued page 49 down hes hoping arrange factur ers demonstrations during meet would flying demos followed show-andtell sessions guys like Byron Bruce Combat Models Marty Silberstein Steve Peacock Cliff Hangar Models Brian Laird Paul Masura Slope Scale Models Other Id imagine itll much like fabulously suc cessful Richland Scale Slope Fun Flyie fly want long have pin Info available writing Charley SSN 2601 E 19th 51 #29 Signal Hill CA 90804 Better call him 1-213/494-3712 1990 Soaring contests Ray Hayes Vice Presi dent LSF wrote remind us now time plan next years big contests Spe cifically Ray talking about every-evenyear LSF Regionals annual NSS Soar-Ins put go-ahead clubs around coun try Theyre bit expensive Ray hoping Continue tradition awarding beautiful LSF plaques LSF Regionals Theyre worth winning Ray also hoping three super con tests NSS Masters LSF Nationals AMA Nats can spread around country 1990 contests West Coast 89 Ray afraid guys east Kansas beginning feel left out youd like info LSF Regionals check Ray 69598 Brookhill Dr Romeo MI 48065 phone 1-313/ 752-6163 NSS Soar-Ins have handled Marshall Long past few years assume youre 90 Marshall Marshalls address 824 Garden Meadow Universal City TX 78148 worry East Coasters hear Nats will Lawrenceville IL 90 RC Aerobatics/Van Putte Continued page 51 aerodynamic center segment wing Youll note root segment tip another segment Figure 4 shows geometric technique solu tion Remember aerodynamic center panel 25% point mean aerody namic chord panel Once youve determined aerodynamic cen ter panel must calculate area panel using Equation 2 measure distance convenient line aerody namic centers panels Figure 4 shows con venient reference line distance re spective aerodynamic centers distance back reference line aerodynamic center wing located determined Equation 3 mean aerodynamic chord complete wing calculated individual values shown Equation 4 looks just like equa tion determining distance wing aero dynamic center doesnt should since 156 Model Aviation SR Battery Packs Make Clean Sweep 89 KRC Electric Fly! Saturday Sunday September 16 17 10th annual KRC Electric Fly held Quakertown PA year two different types endurance events held Saturday Sunday Although weather miserable Saturday up last down event held 12 contestants participated four top finishers using SR packs First place won using SR 1250 Series Magnum pack second place won using SR 1250 Series Magnum pack third place won using SR 1800 Series Magnum pack fourth place won using SR 900 Series Max pack Sunday weather much better different type endurance event held Instead simply longest possible flight contestant made series 4 minute flights 2 minute period between flights retrieve planes allowed recharge change battery packs between flights contestant logged highest number 4 minute flights plus number seconds last flight won objective minimize affect thermals outcome event again SR Battery packs made clean sweep event First place won using SR 1250 Series Magnum pack second place won using SR 1000 Series Max pack third place won using SR 1250 Series Magnum pack As can see comes Electric Power battery packs SR Packs cant beat Two years ago SR recognized need series cells designed exclusively electric flier new series would have give electric fliers longest possible motor runs lowest possible weight new SR Magnum Series cells outgrowth research development Magnum Series cells pack 40% 50% capacity cell increasing its size weight Magnum cells primarily designed Sport applications maximum current load 12 15 amps intermittent applications SRs EP Max Pack Cells other hand designed lowest possible internal impedance could handle extremely high current loads continuous discharge rates 15 30 amps SR Max Pack cells best choice rather Magnum cells addition Electric Flight battery packs SR now Stop source Electric Flight supplies SR now stocks motors props chargers wire connectors switches just about anything else might need Electric Flight addition everyone SR will too happy answer questions help solve problems might have place order ask question can reach us calling Hotline 516-286-0079 between 9am 5pm Monday through Friday youd like us send literature send self addressed business size envelope 50 cents postage SR Batteries Inc Box 287 Bellport NY 11713 -ADVERTISEMENTsame principle involved Now area mean aerodynamic chord aerodynamic center location weird wing have determined can treated like ordinary wing calculation proper center-of-gravity location equation presented July 1988 column can used distance between aerodynamic centers wing horizontal stabilizer L well half horizontal stabilizer area ST two additional items must com puted order determine center-ofgravity should located aft wing aerody namic center equation used Equation 5 same equation July 1988 column Note Since found area mean aerodynamic chord aerodynamic center wing panel side air plane must use half horizontal sta bilizer area want use total stabilizer area double area wing panel just computed Got Next month plan discuss possible expedi tious way handling competition rule changes guarantee wont boring RC Giant Scale/de Vries Continued page 53 Five flight stations provided well covered pit area As usual safe flying name game werent midairs spectators well behind flight line According Bob lots Cubs P-47s P-51s well exotic models latter included all-metal 32lb beauty several twin-engined gas burners Sorry dont have photos big bash therell extensive coverage IMAAs High Flight sure Don Berliner aviation historian par excellence has advised us new organization devoted air racing history Its Society Air Racing Historians based Ohio correspondent has submitted application membership will pass along appropriate address other data know bit about organi zation What weve seen far looks very prom ising indeed As noted earlier column weve received Bert Thompsons quarter-scale drawings Benny Howards Ike Construction has begun sporty wheel pants Theyre 11 long holds two three-inch wheels along beam mechanism will keep everything aligned both air ground some very tricky wire bending involved comes landing gear struts lower ends soldered together along section big safety pin acts spring streamline pants airflow Next agenda make fiberglass cowl rest bird standard construction should breeze Fred Wallman process moving Minnesota retirement home Mesa AZ Before left northern climes assembled Ryan B-S photo session Hes bit ahead yours trulyhe has scale engine place wing struts assembled Ah wing leading edges finished Prolific model designer Don Neill 1120 So 40th St Lincoln NE 68510 has responded very positive way call Giant version Rudy Klings Folkerts SK-3 Actually Don way ahead comment Hes already fly ing prototype model Span model 66 fuselage 87 long Power new A&M Sachs 32 Don promises draw ings will available hes going install retracts Dennis Crooks has 1990 RC Scale Aircraft calendar ready Its another gemfantastic color photography want keep track days 90 contact DC Aviation PO Box 98 Big Rock IL 60511 Dennis will customize calendars club other organization takes credit cards Heres unabashed plug ViP Publishers Inc Dick Phillips yours trulys company now has Henry Haffkes masterful history Gran yule Brothers Gee Bee airplanes print title book Gee Bee REAL Story Granville Brothers Amazing Air planes Its first time author has co operation Granville family producing book about Thompson Trophy-winning rac ers early Thirties Bob Benjamin provided cover painting three- five-view drawings Gee Bee airplanes included soft-backed book Englands Harry Robinson US s Bill Hannan Henry located host photo graphs published before singu lar epic Henry Vein Clemens Williams Bros have published great Giant Scale drawings Gee Bee line aircraft book will come prime documentation source big-bird modelers Price Haffkes opus $2495 plus $200 P&H ViP Publishers Inc PO Box 16103 Colorado Springs CO 80935 December 1989 157
Edition: Model Aviation - 1989/12
Page Numbers: 50, 51, 156, 157
LET pass few hints before getting meat article first two involve adhe sives Ive hobby long enough can re member everyone used Ambroid didnt smell great water-soluble glues like Tite bond Wilhold big improvements cyanoacrylates like Hot Stuff Jet Zap etc same true epoxies con tact cements work great own way some adhesives work better others specific applications book difficult applications adhering servo rails sides polyester epoxy fiberglass fuselages always worried about servo rails pop ping loose fuselage sides hard land ings violent maneuvers fears justi fied sometimes did pop loose used epoxies cyanoacrylates nothing satis factory tried Wilhold R/C 56 adhesive works has combination ot flexibility tenacity makes ideal attaching wood fiberglass gave some pretty severe tests including airplane crash couldnt get turn rails loose fuselage sides R/C 56 white bottle dries clear easy clean up wet rag still wet nothing seems touch dry also use install bulkheads fiberglass fuse lages install hinges attach canopies fuselage works great ever worry wing bolts will pull threads right Out plywood screw too discovered can trickle little cyanoacrylate down threads plywood make times stronger After applying adhesive allow ing set usually rethread hole remove hardened wood fuzz clean up threads will break nylon bolts before pulling out Figure 3 5/2 Equation 1 Equation 2 03 R2RTT2 _ B R-i-T\ 2 77 7 7 7 7 7 7 -4 R R AC Ri T Equation 3 Figure 2 IEquation 4 Equation 5 lvA xl IX21I/1 / X3 / T1 R2 AC C2AC I/ \T2R3 3 T3 I/ / I/ Figure 4 c C1S1C2S2-i-C3S3 Si 53 CG S1S3 C X1S1X2S2X3S3 Si S3 Author Ron Van Putte explains find proper location models center-of-gravity has odd-shaped wing An explanation use figures formulas given months column dont have engineer scientist put method use 50 Model Aviation Radio Control Sport Aerobatics Ron Van Putte I Sleepy Oaks Rd Ft Walton Beach FL 32548 R Figure 1 N T t t / T R 4 threads after treatment last hint involves sanding like goodlooking finish requires lot sanding After applying primer sand After base coat sand Afier subsequent coats sand As said lot sanding Sanding tough work dust goes especially primer coat So re sorted alcohol No drinking welling surface sanded Actually use rubbing alcohol surface Im sanding alcohol must used wet-or-dry sandpaper holds down sanding dust really shortens sand ing time use plastic laboratory bottle squirt some alcohol surface sand until just before surface dries up rub off slimy mess soft cloth think alco hol partially dissolves finish newly painted surfaces epoxies thats what makes sanding go much faster Try meat months column giving method used determine aerodynamic center wings irregularly shaped planforms explaining use information figure out center-of-gravity air plane should Ive gotten enough letters modelers asking think theres enough general interest warrant following discussion key information makes things work calculations locating aerody namic center wing can broken pieces piece contributes its part total aerodynamic inputs can calculated add ing up effects of parts limitations theory because edge effects places pieces join wing has reasonably high aspect ratio pect ratio approximately ratio wing span chord theory works out very well airfoil section has aerodynamic center aerodynamic center place airfoil pitching moment produced air flowing over airfoil independent airfoils angle attack seems unlikely such location exists does airfoils aerodynamic center lo cated point 25% chord back leading edge airfoil wont show inte gral calculus equation determining loca tion aerodynamic center because Model Aviation staff has fits trying get such equations typesetting machine Suffice say aerodynamic center can calcu lated 25% point mean aerody namic chord mean aerodynamic chord also called MAC Sometimes fictitious chord rec tangular wing would produce same forces moments actual wing wing like Figure 1 mean aerodynamic chord calculated Equation 1 Figure 1 also shows what wings mean aero dynamic chord looks like located wing Youll note its mid dle wing mean average chord Theres another way determine aerody namic center just accurate equa tion done properly accurately may have seen several versions geometric tech nique shown Figure 2 intersection two lines drawn diagonally across wing midpoint wing mean aerodynamic chord aerodynamic center located 25% point mean aerodynamic chord Now what about weird-looking wing shown Figure 3 first use either equa tion geometric technique determine Continued page 156 Sport Aerobatic 55 span 51 length 4 channel 14Y2 t wing Symetrical Airfoil Engine 45- 602cy 60- 804 SAVE YOUR FIELD P L2 mutt s ow coet easy nets ghr gI sournct ectuc og mutt e w U no p 0COCC perle ty t s anawe oAMArTtu Se uesuggeetoneandsavngfyng ede Meets AMA muffler rule suggestions 3 10 decIbels quIeter stock muffler No power loss poesible 300-500 RPM Improves engtne Idle s better fuel evunuany Cestly ettached moat 25-108 stoolt mufflers Heat arid Corrosion resistant BlaCk E coat finIsh No speotat adapters requIred WeIghs 35 ozs SN UF-LERTM pso ASP aPsr SNvA Pex P vlNE KAB OS MAX MUFFLER POYAL YS SUP5 FlOPS mutters Patented Kit includes rolled plans cut sanded pans formed landing gear wheel axels steerable tail wheel bracket push rod set other basic hardware 1 SNUF-LER mufflers JTEC IN-COWL mufflers anavaaanrn item F, 29 65 JTEc nvat5es 2496JThcwvvevu cat,, us JT 652 Fe elI 75 nfl jrtc nudfles 2495Thu SNUP-lSP Mutnier cats u5Cd220 rato mwsso JT653 FoeIlOIANTaiaeJTFCnxSSIee 2495 scale ar rattwd JTSC N-COWLrusor5vomanu200 ' lduede ZENOASI supte TIdeS OPS -nutflers elm eta b tu025 St 00 Tow 020 MAXI 30 sULLY SACHS DOLMASSI oTuct ye so,, 05 muffler canom tte tuSSIag84Tn020 N cwo2 N Ft canneeterl ta JTSC muffler59555 euwSan na 20th neearerw tubing Par socearanes teas remaved 50cr Syind -at-- a-- IS net available atysar SaSSy shw asoce oleserte wreediate eSipereet eseek MO Va MC ecoo 5Tuitt accented Add *25090 ups saw So COO 6%Fee ossemonue School St DelCA 94014 ealeetaufo CaIiSooie teeida0t5ate vttt CAnulec14151756-34004 December 1989 51 WARNING Dont fooled Johnny Come Latelys Soft Mounting good airplane effective soft mount used ones use accelerometers ensure LOWEST transmitted vibration backed years proven contest performance UNIVERSAL 11 2cyd engines 20 TO 61EASY ro USE. EVERYTHING INCLUDED FOR MOUNTINGI Available better Hobby Dealers order direct add $175 shipping MADE IN USA manufacturer DISC-LOCK & HUSH rOAM - dealer distributorships invited PERFORMANCE PRODUCTS UALIMITED 7093 E Dodge Rd Ms Morris Ml 48458 e Orders 1313631-4894 /MC accep Kleen Sweep 87995 5500 P & H Check M 0 cyV sa MC Other Kits Avail Wr te free cat 317 525-9074 Crenshaw AeroRR 1 Box 121 ManIlla IN 46150 GATOR RIC PRODUCTS DELUX ALL BALSA KIT An new Tiger Tail 120 four strokes piped 60 two strokes beautiful performer competition just showing offI balsa kit machined wood parts complete lsardware package includes plug-in djustable stab parts new wing mounts Wing Span- 72 inWing Ara 860 sq Complete Delux KitSI 5995 TRANSMITTER CASE An inexpensive rugged molded case protect expensive transmitter both two stick single stick transmitters Black leather grain aluminum trim locking clasp SI 995 MV-I TYPHOON New F3A competition Big beautiful flyer balsa construction plug-in wings 120 four stroke 60 two stroke power Plans-two sheets S 1495 Fiberglass cowl Si 595 Clear butyrate canopy. 5 995 OTHER PLANS Tiger Tail 4S-two sheets 120 four strokesS 1495 TAR baby 120 four strokes51195 Alley Kat 40 size trainer sportS 895 Gator Flea 40 size sport5 895 Bobcat 40 size sportS 895 feather Ilte glass cloth 7 ozsq yd est weave Fastest Filling test Finished Weight Big 3 Sq Yard Pkg Oetailed Instructions- $895 Include $2 SOlItem UPS esidents Add 6% Sales Tax GATOR RIC PRODUCTS 3713 Pompano Dr acola FL 32514 4768639 Letters Editor Continued page 12 Ken opened hobby shop Burk & Company Department Store after World War II worked him full-time year until started college After worked part-time until completing college Milton H Fanning Nashville TN Safety/Preston Continued page 22 some MonoKote repairs moral tale wise keep small extinguisher field box As alter native may possible smother fire towel rag blanket Cub Yellow engine cowling first RC model powered Cox 09 began turn first orange brown able smother fire wrap ping rag around front model Have safe month Keytwo/Randoiph Continued page 30 der everything place range check equipmentand its time fly Flying has wide performance en velope compared Paskey Keytwo basically quite gentle flier Whether upright inverted stall shows abso lutely no tendency snap fact model balanced correctly its very diffi cult make snap snaps bag move center-of-gravity aft about /2 increase elevator throw rate /16 up down movement trailing edge aile rons about right comfortable flying Landings can made nose-high slow full aileron control way touch down problem knife-edge flight first airplane persistently climbed half-loop until learned nose stayed up just little rudder Once Id mastered technique knife-edge loops included Keytwos repertoire tricks what did Eddie Williams have say about latest re-creation see youve built another Paskey said unsung maestro drunken pilot routine Its about time Play again Eddie Radio Technique/Myers Continued page 34 Failsafe Flight System small 15 sq light less ounce inexpensive has very low operating current 70 mA works no doubt nine-volt transistor radio batteries expensive about $250 Duracells live will last long time some chance will get care less let run down some critical time unit meets its claims follow admonition use fresh batteries check servo speed during preflight inspection careless youll probably crash some other reason anyway Failsafe Flight System @ $3995 list T&D Flight Systems PO Box 1782 Staten Island NY 10314 additional information call Alex Kronfeld l-7t8/984-9121 Propeller Noise Continued page 42 cause poor community relations Much cure will depend upon education Modelers need understand nature problem order properly utilize solu tions article has introduced propel ler noise problem provided some neces sary background Subsequent articles will explain test results greater detail describe what modeler can achieve better aircraft performance less noise RC Soaring/Blakeslee Continued page 49 down hes hoping arrange factur ers demonstrations during meet would flying demos followed show-andtell sessions guys like Byron Bruce Combat Models Marty Silberstein Steve Peacock Cliff Hangar Models Brian Laird Paul Masura Slope Scale Models Other Id imagine itll much like fabulously suc cessful Richland Scale Slope Fun Flyie fly want long have pin Info available writing Charley SSN 2601 E 19th 51 #29 Signal Hill CA 90804 Better call him 1-213/494-3712 1990 Soaring contests Ray Hayes Vice Presi dent LSF wrote remind us now time plan next years big contests Spe cifically Ray talking about every-evenyear LSF Regionals annual NSS Soar-Ins put go-ahead clubs around coun try Theyre bit expensive Ray hoping Continue tradition awarding beautiful LSF plaques LSF Regionals Theyre worth winning Ray also hoping three super con tests NSS Masters LSF Nationals AMA Nats can spread around country 1990 contests West Coast 89 Ray afraid guys east Kansas beginning feel left out youd like info LSF Regionals check Ray 69598 Brookhill Dr Romeo MI 48065 phone 1-313/ 752-6163 NSS Soar-Ins have handled Marshall Long past few years assume youre 90 Marshall Marshalls address 824 Garden Meadow Universal City TX 78148 worry East Coasters hear Nats will Lawrenceville IL 90 RC Aerobatics/Van Putte Continued page 51 aerodynamic center segment wing Youll note root segment tip another segment Figure 4 shows geometric technique solu tion Remember aerodynamic center panel 25% point mean aerody namic chord panel Once youve determined aerodynamic cen ter panel must calculate area panel using Equation 2 measure distance convenient line aerody namic centers panels Figure 4 shows con venient reference line distance re spective aerodynamic centers distance back reference line aerodynamic center wing located determined Equation 3 mean aerodynamic chord complete wing calculated individual values shown Equation 4 looks just like equa tion determining distance wing aero dynamic center doesnt should since 156 Model Aviation SR Battery Packs Make Clean Sweep 89 KRC Electric Fly! Saturday Sunday September 16 17 10th annual KRC Electric Fly held Quakertown PA year two different types endurance events held Saturday Sunday Although weather miserable Saturday up last down event held 12 contestants participated four top finishers using SR packs First place won using SR 1250 Series Magnum pack second place won using SR 1250 Series Magnum pack third place won using SR 1800 Series Magnum pack fourth place won using SR 900 Series Max pack Sunday weather much better different type endurance event held Instead simply longest possible flight contestant made series 4 minute flights 2 minute period between flights retrieve planes allowed recharge change battery packs between flights contestant logged highest number 4 minute flights plus number seconds last flight won objective minimize affect thermals outcome event again SR Battery packs made clean sweep event First place won using SR 1250 Series Magnum pack second place won using SR 1000 Series Max pack third place won using SR 1250 Series Magnum pack As can see comes Electric Power battery packs SR Packs cant beat Two years ago SR recognized need series cells designed exclusively electric flier new series would have give electric fliers longest possible motor runs lowest possible weight new SR Magnum Series cells outgrowth research development Magnum Series cells pack 40% 50% capacity cell increasing its size weight Magnum cells primarily designed Sport applications maximum current load 12 15 amps intermittent applications SRs EP Max Pack Cells other hand designed lowest possible internal impedance could handle extremely high current loads continuous discharge rates 15 30 amps SR Max Pack cells best choice rather Magnum cells addition Electric Flight battery packs SR now Stop source Electric Flight supplies SR now stocks motors props chargers wire connectors switches just about anything else might need Electric Flight addition everyone SR will too happy answer questions help solve problems might have place order ask question can reach us calling Hotline 516-286-0079 between 9am 5pm Monday through Friday youd like us send literature send self addressed business size envelope 50 cents postage SR Batteries Inc Box 287 Bellport NY 11713 -ADVERTISEMENTsame principle involved Now area mean aerodynamic chord aerodynamic center location weird wing have determined can treated like ordinary wing calculation proper center-of-gravity location equation presented July 1988 column can used distance between aerodynamic centers wing horizontal stabilizer L well half horizontal stabilizer area ST two additional items must com puted order determine center-ofgravity should located aft wing aerody namic center equation used Equation 5 same equation July 1988 column Note Since found area mean aerodynamic chord aerodynamic center wing panel side air plane must use half horizontal sta bilizer area want use total stabilizer area double area wing panel just computed Got Next month plan discuss possible expedi tious way handling competition rule changes guarantee wont boring RC Giant Scale/de Vries Continued page 53 Five flight stations provided well covered pit area As usual safe flying name game werent midairs spectators well behind flight line According Bob lots Cubs P-47s P-51s well exotic models latter included all-metal 32lb beauty several twin-engined gas burners Sorry dont have photos big bash therell extensive coverage IMAAs High Flight sure Don Berliner aviation historian par excellence has advised us new organization devoted air racing history Its Society Air Racing Historians based Ohio correspondent has submitted application membership will pass along appropriate address other data know bit about organi zation What weve seen far looks very prom ising indeed As noted earlier column weve received Bert Thompsons quarter-scale drawings Benny Howards Ike Construction has begun sporty wheel pants Theyre 11 long holds two three-inch wheels along beam mechanism will keep everything aligned both air ground some very tricky wire bending involved comes landing gear struts lower ends soldered together along section big safety pin acts spring streamline pants airflow Next agenda make fiberglass cowl rest bird standard construction should breeze Fred Wallman process moving Minnesota retirement home Mesa AZ Before left northern climes assembled Ryan B-S photo session Hes bit ahead yours trulyhe has scale engine place wing struts assembled Ah wing leading edges finished Prolific model designer Don Neill 1120 So 40th St Lincoln NE 68510 has responded very positive way call Giant version Rudy Klings Folkerts SK-3 Actually Don way ahead comment Hes already fly ing prototype model Span model 66 fuselage 87 long Power new A&M Sachs 32 Don promises draw ings will available hes going install retracts Dennis Crooks has 1990 RC Scale Aircraft calendar ready Its another gemfantastic color photography want keep track days 90 contact DC Aviation PO Box 98 Big Rock IL 60511 Dennis will customize calendars club other organization takes credit cards Heres unabashed plug ViP Publishers Inc Dick Phillips yours trulys company now has Henry Haffkes masterful history Gran yule Brothers Gee Bee airplanes print title book Gee Bee REAL Story Granville Brothers Amazing Air planes Its first time author has co operation Granville family producing book about Thompson Trophy-winning rac ers early Thirties Bob Benjamin provided cover painting three- five-view drawings Gee Bee airplanes included soft-backed book Englands Harry Robinson US s Bill Hannan Henry located host photo graphs published before singu lar epic Henry Vein Clemens Williams Bros have published great Giant Scale drawings Gee Bee line aircraft book will come prime documentation source big-bird modelers Price Haffkes opus $2495 plus $200 P&H ViP Publishers Inc PO Box 16103 Colorado Springs CO 80935 December 1989 157
Edition: Model Aviation - 1989/12
Page Numbers: 50, 51, 156, 157
LET pass few hints before getting meat article first two involve adhe sives Ive hobby long enough can re member everyone used Ambroid didnt smell great water-soluble glues like Tite bond Wilhold big improvements cyanoacrylates like Hot Stuff Jet Zap etc same true epoxies con tact cements work great own way some adhesives work better others specific applications book difficult applications adhering servo rails sides polyester epoxy fiberglass fuselages always worried about servo rails pop ping loose fuselage sides hard land ings violent maneuvers fears justi fied sometimes did pop loose used epoxies cyanoacrylates nothing satis factory tried Wilhold R/C 56 adhesive works has combination ot flexibility tenacity makes ideal attaching wood fiberglass gave some pretty severe tests including airplane crash couldnt get turn rails loose fuselage sides R/C 56 white bottle dries clear easy clean up wet rag still wet nothing seems touch dry also use install bulkheads fiberglass fuse lages install hinges attach canopies fuselage works great ever worry wing bolts will pull threads right Out plywood screw too discovered can trickle little cyanoacrylate down threads plywood make times stronger After applying adhesive allow ing set usually rethread hole remove hardened wood fuzz clean up threads will break nylon bolts before pulling out Figure 3 5/2 Equation 1 Equation 2 03 R2RTT2 _ B R-i-T\ 2 77 7 7 7 7 7 7 -4 R R AC Ri T Equation 3 Figure 2 IEquation 4 Equation 5 lvA xl IX21I/1 / X3 / T1 R2 AC C2AC I/ \T2R3 3 T3 I/ / I/ Figure 4 c C1S1C2S2-i-C3S3 Si 53 CG S1S3 C X1S1X2S2X3S3 Si S3 Author Ron Van Putte explains find proper location models center-of-gravity has odd-shaped wing An explanation use figures formulas given months column dont have engineer scientist put method use 50 Model Aviation Radio Control Sport Aerobatics Ron Van Putte I Sleepy Oaks Rd Ft Walton Beach FL 32548 R Figure 1 N T t t / T R 4 threads after treatment last hint involves sanding like goodlooking finish requires lot sanding After applying primer sand After base coat sand Afier subsequent coats sand As said lot sanding Sanding tough work dust goes especially primer coat So re sorted alcohol No drinking welling surface sanded Actually use rubbing alcohol surface Im sanding alcohol must used wet-or-dry sandpaper holds down sanding dust really shortens sand ing time use plastic laboratory bottle squirt some alcohol surface sand until just before surface dries up rub off slimy mess soft cloth think alco hol partially dissolves finish newly painted surfaces epoxies thats what makes sanding go much faster Try meat months column giving method used determine aerodynamic center wings irregularly shaped planforms explaining use information figure out center-of-gravity air plane should Ive gotten enough letters modelers asking think theres enough general interest warrant following discussion key information makes things work calculations locating aerody namic center wing can broken pieces piece contributes its part total aerodynamic inputs can calculated add ing up effects of parts limitations theory because edge effects places pieces join wing has reasonably high aspect ratio pect ratio approximately ratio wing span chord theory works out very well airfoil section has aerodynamic center aerodynamic center place airfoil pitching moment produced air flowing over airfoil independent airfoils angle attack seems unlikely such location exists does airfoils aerodynamic center lo cated point 25% chord back leading edge airfoil wont show inte gral calculus equation determining loca tion aerodynamic center because Model Aviation staff has fits trying get such equations typesetting machine Suffice say aerodynamic center can calcu lated 25% point mean aerody namic chord mean aerodynamic chord also called MAC Sometimes fictitious chord rec tangular wing would produce same forces moments actual wing wing like Figure 1 mean aerodynamic chord calculated Equation 1 Figure 1 also shows what wings mean aero dynamic chord looks like located wing Youll note its mid dle wing mean average chord Theres another way determine aerody namic center just accurate equa tion done properly accurately may have seen several versions geometric tech nique shown Figure 2 intersection two lines drawn diagonally across wing midpoint wing mean aerodynamic chord aerodynamic center located 25% point mean aerodynamic chord Now what about weird-looking wing shown Figure 3 first use either equa tion geometric technique determine Continued page 156 Sport Aerobatic 55 span 51 length 4 channel 14Y2 t wing Symetrical Airfoil Engine 45- 602cy 60- 804 SAVE YOUR FIELD P L2 mutt s ow coet easy nets ghr gI sournct ectuc og mutt e w U no p 0COCC perle ty t s anawe oAMArTtu Se uesuggeetoneandsavngfyng ede Meets AMA muffler rule suggestions 3 10 decIbels quIeter stock muffler No power loss poesible 300-500 RPM Improves engtne Idle s better fuel evunuany Cestly ettached moat 25-108 stoolt mufflers Heat arid Corrosion resistant BlaCk E coat finIsh No speotat adapters requIred WeIghs 35 ozs SN UF-LERTM pso ASP aPsr SNvA Pex P vlNE KAB OS MAX MUFFLER POYAL YS SUP5 FlOPS mutters Patented Kit includes rolled plans cut sanded pans formed landing gear wheel axels steerable tail wheel bracket push rod set other basic hardware 1 SNUF-LER mufflers JTEC IN-COWL mufflers anavaaanrn item F, 29 65 JTEc nvat5es 2496JThcwvvevu cat,, us JT 652 Fe elI 75 nfl jrtc nudfles 2495Thu SNUP-lSP Mutnier cats u5Cd220 rato mwsso JT653 FoeIlOIANTaiaeJTFCnxSSIee 2495 scale ar rattwd JTSC N-COWLrusor5vomanu200 ' lduede ZENOASI supte TIdeS OPS -nutflers elm eta b tu025 St 00 Tow 020 MAXI 30 sULLY SACHS DOLMASSI oTuct ye so,, 05 muffler canom tte tuSSIag84Tn020 N cwo2 N Ft canneeterl ta JTSC muffler59555 euwSan na 20th neearerw tubing Par socearanes teas remaved 50cr Syind -at-- a-- IS net available atysar SaSSy shw asoce oleserte wreediate eSipereet eseek MO Va MC ecoo 5Tuitt accented Add *25090 ups saw So COO 6%Fee ossemonue School St DelCA 94014 ealeetaufo CaIiSooie teeida0t5ate vttt CAnulec14151756-34004 December 1989 51 WARNING Dont fooled Johnny Come Latelys Soft Mounting good airplane effective soft mount used ones use accelerometers ensure LOWEST transmitted vibration backed years proven contest performance UNIVERSAL 11 2cyd engines 20 TO 61EASY ro USE. EVERYTHING INCLUDED FOR MOUNTINGI Available better Hobby Dealers order direct add $175 shipping MADE IN USA manufacturer DISC-LOCK & HUSH rOAM - dealer distributorships invited PERFORMANCE PRODUCTS UALIMITED 7093 E Dodge Rd Ms Morris Ml 48458 e Orders 1313631-4894 /MC accep Kleen Sweep 87995 5500 P & H Check M 0 cyV sa MC Other Kits Avail Wr te free cat 317 525-9074 Crenshaw AeroRR 1 Box 121 ManIlla IN 46150 GATOR RIC PRODUCTS DELUX ALL BALSA KIT An new Tiger Tail 120 four strokes piped 60 two strokes beautiful performer competition just showing offI balsa kit machined wood parts complete lsardware package includes plug-in djustable stab parts new wing mounts Wing Span- 72 inWing Ara 860 sq Complete Delux KitSI 5995 TRANSMITTER CASE An inexpensive rugged molded case protect expensive transmitter both two stick single stick transmitters Black leather grain aluminum trim locking clasp SI 995 MV-I TYPHOON New F3A competition Big beautiful flyer balsa construction plug-in wings 120 four stroke 60 two stroke power Plans-two sheets S 1495 Fiberglass cowl Si 595 Clear butyrate canopy. 5 995 OTHER PLANS Tiger Tail 4S-two sheets 120 four strokesS 1495 TAR baby 120 four strokes51195 Alley Kat 40 size trainer sportS 895 Gator Flea 40 size sport5 895 Bobcat 40 size sportS 895 feather Ilte glass cloth 7 ozsq yd est weave Fastest Filling test Finished Weight Big 3 Sq Yard Pkg Oetailed Instructions- $895 Include $2 SOlItem UPS esidents Add 6% Sales Tax GATOR RIC PRODUCTS 3713 Pompano Dr acola FL 32514 4768639 Letters Editor Continued page 12 Ken opened hobby shop Burk & Company Department Store after World War II worked him full-time year until started college After worked part-time until completing college Milton H Fanning Nashville TN Safety/Preston Continued page 22 some MonoKote repairs moral tale wise keep small extinguisher field box As alter native may possible smother fire towel rag blanket Cub Yellow engine cowling first RC model powered Cox 09 began turn first orange brown able smother fire wrap ping rag around front model Have safe month Keytwo/Randoiph Continued page 30 der everything place range check equipmentand its time fly Flying has wide performance en velope compared Paskey Keytwo basically quite gentle flier Whether upright inverted stall shows abso lutely no tendency snap fact model balanced correctly its very diffi cult make snap snaps bag move center-of-gravity aft about /2 increase elevator throw rate /16 up down movement trailing edge aile rons about right comfortable flying Landings can made nose-high slow full aileron control way touch down problem knife-edge flight first airplane persistently climbed half-loop until learned nose stayed up just little rudder Once Id mastered technique knife-edge loops included Keytwos repertoire tricks what did Eddie Williams have say about latest re-creation see youve built another Paskey said unsung maestro drunken pilot routine Its about time Play again Eddie Radio Technique/Myers Continued page 34 Failsafe Flight System small 15 sq light less ounce inexpensive has very low operating current 70 mA works no doubt nine-volt transistor radio batteries expensive about $250 Duracells live will last long time some chance will get care less let run down some critical time unit meets its claims follow admonition use fresh batteries check servo speed during preflight inspection careless youll probably crash some other reason anyway Failsafe Flight System @ $3995 list T&D Flight Systems PO Box 1782 Staten Island NY 10314 additional information call Alex Kronfeld l-7t8/984-9121 Propeller Noise Continued page 42 cause poor community relations Much cure will depend upon education Modelers need understand nature problem order properly utilize solu tions article has introduced propel ler noise problem provided some neces sary background Subsequent articles will explain test results greater detail describe what modeler can achieve better aircraft performance less noise RC Soaring/Blakeslee Continued page 49 down hes hoping arrange factur ers demonstrations during meet would flying demos followed show-andtell sessions guys like Byron Bruce Combat Models Marty Silberstein Steve Peacock Cliff Hangar Models Brian Laird Paul Masura Slope Scale Models Other Id imagine itll much like fabulously suc cessful Richland Scale Slope Fun Flyie fly want long have pin Info available writing Charley SSN 2601 E 19th 51 #29 Signal Hill CA 90804 Better call him 1-213/494-3712 1990 Soaring contests Ray Hayes Vice Presi dent LSF wrote remind us now time plan next years big contests Spe cifically Ray talking about every-evenyear LSF Regionals annual NSS Soar-Ins put go-ahead clubs around coun try Theyre bit expensive Ray hoping Continue tradition awarding beautiful LSF plaques LSF Regionals Theyre worth winning Ray also hoping three super con tests NSS Masters LSF Nationals AMA Nats can spread around country 1990 contests West Coast 89 Ray afraid guys east Kansas beginning feel left out youd like info LSF Regionals check Ray 69598 Brookhill Dr Romeo MI 48065 phone 1-313/ 752-6163 NSS Soar-Ins have handled Marshall Long past few years assume youre 90 Marshall Marshalls address 824 Garden Meadow Universal City TX 78148 worry East Coasters hear Nats will Lawrenceville IL 90 RC Aerobatics/Van Putte Continued page 51 aerodynamic center segment wing Youll note root segment tip another segment Figure 4 shows geometric technique solu tion Remember aerodynamic center panel 25% point mean aerody namic chord panel Once youve determined aerodynamic cen ter panel must calculate area panel using Equation 2 measure distance convenient line aerody namic centers panels Figure 4 shows con venient reference line distance re spective aerodynamic centers distance back reference line aerodynamic center wing located determined Equation 3 mean aerodynamic chord complete wing calculated individual values shown Equation 4 looks just like equa tion determining distance wing aero dynamic center doesnt should since 156 Model Aviation SR Battery Packs Make Clean Sweep 89 KRC Electric Fly! Saturday Sunday September 16 17 10th annual KRC Electric Fly held Quakertown PA year two different types endurance events held Saturday Sunday Although weather miserable Saturday up last down event held 12 contestants participated four top finishers using SR packs First place won using SR 1250 Series Magnum pack second place won using SR 1250 Series Magnum pack third place won using SR 1800 Series Magnum pack fourth place won using SR 900 Series Max pack Sunday weather much better different type endurance event held Instead simply longest possible flight contestant made series 4 minute flights 2 minute period between flights retrieve planes allowed recharge change battery packs between flights contestant logged highest number 4 minute flights plus number seconds last flight won objective minimize affect thermals outcome event again SR Battery packs made clean sweep event First place won using SR 1250 Series Magnum pack second place won using SR 1000 Series Max pack third place won using SR 1250 Series Magnum pack As can see comes Electric Power battery packs SR Packs cant beat Two years ago SR recognized need series cells designed exclusively electric flier new series would have give electric fliers longest possible motor runs lowest possible weight new SR Magnum Series cells outgrowth research development Magnum Series cells pack 40% 50% capacity cell increasing its size weight Magnum cells primarily designed Sport applications maximum current load 12 15 amps intermittent applications SRs EP Max Pack Cells other hand designed lowest possible internal impedance could handle extremely high current loads continuous discharge rates 15 30 amps SR Max Pack cells best choice rather Magnum cells addition Electric Flight battery packs SR now Stop source Electric Flight supplies SR now stocks motors props chargers wire connectors switches just about anything else might need Electric Flight addition everyone SR will too happy answer questions help solve problems might have place order ask question can reach us calling Hotline 516-286-0079 between 9am 5pm Monday through Friday youd like us send literature send self addressed business size envelope 50 cents postage SR Batteries Inc Box 287 Bellport NY 11713 -ADVERTISEMENTsame principle involved Now area mean aerodynamic chord aerodynamic center location weird wing have determined can treated like ordinary wing calculation proper center-of-gravity location equation presented July 1988 column can used distance between aerodynamic centers wing horizontal stabilizer L well half horizontal stabilizer area ST two additional items must com puted order determine center-ofgravity should located aft wing aerody namic center equation used Equation 5 same equation July 1988 column Note Since found area mean aerodynamic chord aerodynamic center wing panel side air plane must use half horizontal sta bilizer area want use total stabilizer area double area wing panel just computed Got Next month plan discuss possible expedi tious way handling competition rule changes guarantee wont boring RC Giant Scale/de Vries Continued page 53 Five flight stations provided well covered pit area As usual safe flying name game werent midairs spectators well behind flight line According Bob lots Cubs P-47s P-51s well exotic models latter included all-metal 32lb beauty several twin-engined gas burners Sorry dont have photos big bash therell extensive coverage IMAAs High Flight sure Don Berliner aviation historian par excellence has advised us new organization devoted air racing history Its Society Air Racing Historians based Ohio correspondent has submitted application membership will pass along appropriate address other data know bit about organi zation What weve seen far looks very prom ising indeed As noted earlier column weve received Bert Thompsons quarter-scale drawings Benny Howards Ike Construction has begun sporty wheel pants Theyre 11 long holds two three-inch wheels along beam mechanism will keep everything aligned both air ground some very tricky wire bending involved comes landing gear struts lower ends soldered together along section big safety pin acts spring streamline pants airflow Next agenda make fiberglass cowl rest bird standard construction should breeze Fred Wallman process moving Minnesota retirement home Mesa AZ Before left northern climes assembled Ryan B-S photo session Hes bit ahead yours trulyhe has scale engine place wing struts assembled Ah wing leading edges finished Prolific model designer Don Neill 1120 So 40th St Lincoln NE 68510 has responded very positive way call Giant version Rudy Klings Folkerts SK-3 Actually Don way ahead comment Hes already fly ing prototype model Span model 66 fuselage 87 long Power new A&M Sachs 32 Don promises draw ings will available hes going install retracts Dennis Crooks has 1990 RC Scale Aircraft calendar ready Its another gemfantastic color photography want keep track days 90 contact DC Aviation PO Box 98 Big Rock IL 60511 Dennis will customize calendars club other organization takes credit cards Heres unabashed plug ViP Publishers Inc Dick Phillips yours trulys company now has Henry Haffkes masterful history Gran yule Brothers Gee Bee airplanes print title book Gee Bee REAL Story Granville Brothers Amazing Air planes Its first time author has co operation Granville family producing book about Thompson Trophy-winning rac ers early Thirties Bob Benjamin provided cover painting three- five-view drawings Gee Bee airplanes included soft-backed book Englands Harry Robinson US s Bill Hannan Henry located host photo graphs published before singu lar epic Henry Vein Clemens Williams Bros have published great Giant Scale drawings Gee Bee line aircraft book will come prime documentation source big-bird modelers Price Haffkes opus $2495 plus $200 P&H ViP Publishers Inc PO Box 16103 Colorado Springs CO 80935 December 1989 157
Edition: Model Aviation - 1989/12
Page Numbers: 50, 51, 156, 157
LET pass few hints before getting meat article first two involve adhe sives Ive hobby long enough can re member everyone used Ambroid didnt smell great water-soluble glues like Tite bond Wilhold big improvements cyanoacrylates like Hot Stuff Jet Zap etc same true epoxies con tact cements work great own way some adhesives work better others specific applications book difficult applications adhering servo rails sides polyester epoxy fiberglass fuselages always worried about servo rails pop ping loose fuselage sides hard land ings violent maneuvers fears justi fied sometimes did pop loose used epoxies cyanoacrylates nothing satis factory tried Wilhold R/C 56 adhesive works has combination ot flexibility tenacity makes ideal attaching wood fiberglass gave some pretty severe tests including airplane crash couldnt get turn rails loose fuselage sides R/C 56 white bottle dries clear easy clean up wet rag still wet nothing seems touch dry also use install bulkheads fiberglass fuse lages install hinges attach canopies fuselage works great ever worry wing bolts will pull threads right Out plywood screw too discovered can trickle little cyanoacrylate down threads plywood make times stronger After applying adhesive allow ing set usually rethread hole remove hardened wood fuzz clean up threads will break nylon bolts before pulling out Figure 3 5/2 Equation 1 Equation 2 03 R2RTT2 _ B R-i-T\ 2 77 7 7 7 7 7 7 -4 R R AC Ri T Equation 3 Figure 2 IEquation 4 Equation 5 lvA xl IX21I/1 / X3 / T1 R2 AC C2AC I/ \T2R3 3 T3 I/ / I/ Figure 4 c C1S1C2S2-i-C3S3 Si 53 CG S1S3 C X1S1X2S2X3S3 Si S3 Author Ron Van Putte explains find proper location models center-of-gravity has odd-shaped wing An explanation use figures formulas given months column dont have engineer scientist put method use 50 Model Aviation Radio Control Sport Aerobatics Ron Van Putte I Sleepy Oaks Rd Ft Walton Beach FL 32548 R Figure 1 N T t t / T R 4 threads after treatment last hint involves sanding like goodlooking finish requires lot sanding After applying primer sand After base coat sand Afier subsequent coats sand As said lot sanding Sanding tough work dust goes especially primer coat So re sorted alcohol No drinking welling surface sanded Actually use rubbing alcohol surface Im sanding alcohol must used wet-or-dry sandpaper holds down sanding dust really shortens sand ing time use plastic laboratory bottle squirt some alcohol surface sand until just before surface dries up rub off slimy mess soft cloth think alco hol partially dissolves finish newly painted surfaces epoxies thats what makes sanding go much faster Try meat months column giving method used determine aerodynamic center wings irregularly shaped planforms explaining use information figure out center-of-gravity air plane should Ive gotten enough letters modelers asking think theres enough general interest warrant following discussion key information makes things work calculations locating aerody namic center wing can broken pieces piece contributes its part total aerodynamic inputs can calculated add ing up effects of parts limitations theory because edge effects places pieces join wing has reasonably high aspect ratio pect ratio approximately ratio wing span chord theory works out very well airfoil section has aerodynamic center aerodynamic center place airfoil pitching moment produced air flowing over airfoil independent airfoils angle attack seems unlikely such location exists does airfoils aerodynamic center lo cated point 25% chord back leading edge airfoil wont show inte gral calculus equation determining loca tion aerodynamic center because Model Aviation staff has fits trying get such equations typesetting machine Suffice say aerodynamic center can calcu lated 25% point mean aerody namic chord mean aerodynamic chord also called MAC Sometimes fictitious chord rec tangular wing would produce same forces moments actual wing wing like Figure 1 mean aerodynamic chord calculated Equation 1 Figure 1 also shows what wings mean aero dynamic chord looks like located wing Youll note its mid dle wing mean average chord Theres another way determine aerody namic center just accurate equa tion done properly accurately may have seen several versions geometric tech nique shown Figure 2 intersection two lines drawn diagonally across wing midpoint wing mean aerodynamic chord aerodynamic center located 25% point mean aerodynamic chord Now what about weird-looking wing shown Figure 3 first use either equa tion geometric technique determine Continued page 156 Sport Aerobatic 55 span 51 length 4 channel 14Y2 t wing Symetrical Airfoil Engine 45- 602cy 60- 804 SAVE YOUR FIELD P L2 mutt s ow coet easy nets ghr gI sournct ectuc og mutt e w U no p 0COCC perle ty t s anawe oAMArTtu Se uesuggeetoneandsavngfyng ede Meets AMA muffler rule suggestions 3 10 decIbels quIeter stock muffler No power loss poesible 300-500 RPM Improves engtne Idle s better fuel evunuany Cestly ettached moat 25-108 stoolt mufflers Heat arid Corrosion resistant BlaCk E coat finIsh No speotat adapters requIred WeIghs 35 ozs SN UF-LERTM pso ASP aPsr SNvA Pex P vlNE KAB OS MAX MUFFLER POYAL YS SUP5 FlOPS mutters Patented Kit includes rolled plans cut sanded pans formed landing gear wheel axels steerable tail wheel bracket push rod set other basic hardware 1 SNUF-LER mufflers JTEC IN-COWL mufflers anavaaanrn item F, 29 65 JTEc nvat5es 2496JThcwvvevu cat,, us JT 652 Fe elI 75 nfl jrtc nudfles 2495Thu SNUP-lSP Mutnier cats u5Cd220 rato mwsso JT653 FoeIlOIANTaiaeJTFCnxSSIee 2495 scale ar rattwd JTSC N-COWLrusor5vomanu200 ' lduede ZENOASI supte TIdeS OPS -nutflers elm eta b tu025 St 00 Tow 020 MAXI 30 sULLY SACHS DOLMASSI oTuct ye so,, 05 muffler canom tte tuSSIag84Tn020 N cwo2 N Ft canneeterl ta JTSC muffler59555 euwSan na 20th neearerw tubing Par socearanes teas remaved 50cr Syind -at-- a-- IS net available atysar SaSSy shw asoce oleserte wreediate eSipereet eseek MO Va MC ecoo 5Tuitt accented Add *25090 ups saw So COO 6%Fee ossemonue School St DelCA 94014 ealeetaufo CaIiSooie teeida0t5ate vttt CAnulec14151756-34004 December 1989 51 WARNING Dont fooled Johnny Come Latelys Soft Mounting good airplane effective soft mount used ones use accelerometers ensure LOWEST transmitted vibration backed years proven contest performance UNIVERSAL 11 2cyd engines 20 TO 61EASY ro USE. EVERYTHING INCLUDED FOR MOUNTINGI Available better Hobby Dealers order direct add $175 shipping MADE IN USA manufacturer DISC-LOCK & HUSH rOAM - dealer distributorships invited PERFORMANCE PRODUCTS UALIMITED 7093 E Dodge Rd Ms Morris Ml 48458 e Orders 1313631-4894 /MC accep Kleen Sweep 87995 5500 P & H Check M 0 cyV sa MC Other Kits Avail Wr te free cat 317 525-9074 Crenshaw AeroRR 1 Box 121 ManIlla IN 46150 GATOR RIC PRODUCTS DELUX ALL BALSA KIT An new Tiger Tail 120 four strokes piped 60 two strokes beautiful performer competition just showing offI balsa kit machined wood parts complete lsardware package includes plug-in djustable stab parts new wing mounts Wing Span- 72 inWing Ara 860 sq Complete Delux KitSI 5995 TRANSMITTER CASE An inexpensive rugged molded case protect expensive transmitter both two stick single stick transmitters Black leather grain aluminum trim locking clasp SI 995 MV-I TYPHOON New F3A competition Big beautiful flyer balsa construction plug-in wings 120 four stroke 60 two stroke power Plans-two sheets S 1495 Fiberglass cowl Si 595 Clear butyrate canopy. 5 995 OTHER PLANS Tiger Tail 4S-two sheets 120 four strokesS 1495 TAR baby 120 four strokes51195 Alley Kat 40 size trainer sportS 895 Gator Flea 40 size sport5 895 Bobcat 40 size sportS 895 feather Ilte glass cloth 7 ozsq yd est weave Fastest Filling test Finished Weight Big 3 Sq Yard Pkg Oetailed Instructions- $895 Include $2 SOlItem UPS esidents Add 6% Sales Tax GATOR RIC PRODUCTS 3713 Pompano Dr acola FL 32514 4768639 Letters Editor Continued page 12 Ken opened hobby shop Burk & Company Department Store after World War II worked him full-time year until started college After worked part-time until completing college Milton H Fanning Nashville TN Safety/Preston Continued page 22 some MonoKote repairs moral tale wise keep small extinguisher field box As alter native may possible smother fire towel rag blanket Cub Yellow engine cowling first RC model powered Cox 09 began turn first orange brown able smother fire wrap ping rag around front model Have safe month Keytwo/Randoiph Continued page 30 der everything place range check equipmentand its time fly Flying has wide performance en velope compared Paskey Keytwo basically quite gentle flier Whether upright inverted stall shows abso lutely no tendency snap fact model balanced correctly its very diffi cult make snap snaps bag move center-of-gravity aft about /2 increase elevator throw rate /16 up down movement trailing edge aile rons about right comfortable flying Landings can made nose-high slow full aileron control way touch down problem knife-edge flight first airplane persistently climbed half-loop until learned nose stayed up just little rudder Once Id mastered technique knife-edge loops included Keytwos repertoire tricks what did Eddie Williams have say about latest re-creation see youve built another Paskey said unsung maestro drunken pilot routine Its about time Play again Eddie Radio Technique/Myers Continued page 34 Failsafe Flight System small 15 sq light less ounce inexpensive has very low operating current 70 mA works no doubt nine-volt transistor radio batteries expensive about $250 Duracells live will last long time some chance will get care less let run down some critical time unit meets its claims follow admonition use fresh batteries check servo speed during preflight inspection careless youll probably crash some other reason anyway Failsafe Flight System @ $3995 list T&D Flight Systems PO Box 1782 Staten Island NY 10314 additional information call Alex Kronfeld l-7t8/984-9121 Propeller Noise Continued page 42 cause poor community relations Much cure will depend upon education Modelers need understand nature problem order properly utilize solu tions article has introduced propel ler noise problem provided some neces sary background Subsequent articles will explain test results greater detail describe what modeler can achieve better aircraft performance less noise RC Soaring/Blakeslee Continued page 49 down hes hoping arrange factur ers demonstrations during meet would flying demos followed show-andtell sessions guys like Byron Bruce Combat Models Marty Silberstein Steve Peacock Cliff Hangar Models Brian Laird Paul Masura Slope Scale Models Other Id imagine itll much like fabulously suc cessful Richland Scale Slope Fun Flyie fly want long have pin Info available writing Charley SSN 2601 E 19th 51 #29 Signal Hill CA 90804 Better call him 1-213/494-3712 1990 Soaring contests Ray Hayes Vice Presi dent LSF wrote remind us now time plan next years big contests Spe cifically Ray talking about every-evenyear LSF Regionals annual NSS Soar-Ins put go-ahead clubs around coun try Theyre bit expensive Ray hoping Continue tradition awarding beautiful LSF plaques LSF Regionals Theyre worth winning Ray also hoping three super con tests NSS Masters LSF Nationals AMA Nats can spread around country 1990 contests West Coast 89 Ray afraid guys east Kansas beginning feel left out youd like info LSF Regionals check Ray 69598 Brookhill Dr Romeo MI 48065 phone 1-313/ 752-6163 NSS Soar-Ins have handled Marshall Long past few years assume youre 90 Marshall Marshalls address 824 Garden Meadow Universal City TX 78148 worry East Coasters hear Nats will Lawrenceville IL 90 RC Aerobatics/Van Putte Continued page 51 aerodynamic center segment wing Youll note root segment tip another segment Figure 4 shows geometric technique solu tion Remember aerodynamic center panel 25% point mean aerody namic chord panel Once youve determined aerodynamic cen ter panel must calculate area panel using Equation 2 measure distance convenient line aerody namic centers panels Figure 4 shows con venient reference line distance re spective aerodynamic centers distance back reference line aerodynamic center wing located determined Equation 3 mean aerodynamic chord complete wing calculated individual values shown Equation 4 looks just like equa tion determining distance wing aero dynamic center doesnt should since 156 Model Aviation SR Battery Packs Make Clean Sweep 89 KRC Electric Fly! Saturday Sunday September 16 17 10th annual KRC Electric Fly held Quakertown PA year two different types endurance events held Saturday Sunday Although weather miserable Saturday up last down event held 12 contestants participated four top finishers using SR packs First place won using SR 1250 Series Magnum pack second place won using SR 1250 Series Magnum pack third place won using SR 1800 Series Magnum pack fourth place won using SR 900 Series Max pack Sunday weather much better different type endurance event held Instead simply longest possible flight contestant made series 4 minute flights 2 minute period between flights retrieve planes allowed recharge change battery packs between flights contestant logged highest number 4 minute flights plus number seconds last flight won objective minimize affect thermals outcome event again SR Battery packs made clean sweep event First place won using SR 1250 Series Magnum pack second place won using SR 1000 Series Max pack third place won using SR 1250 Series Magnum pack As can see comes Electric Power battery packs SR Packs cant beat Two years ago SR recognized need series cells designed exclusively electric flier new series would have give electric fliers longest possible motor runs lowest possible weight new SR Magnum Series cells outgrowth research development Magnum Series cells pack 40% 50% capacity cell increasing its size weight Magnum cells primarily designed Sport applications maximum current load 12 15 amps intermittent applications SRs EP Max Pack Cells other hand designed lowest possible internal impedance could handle extremely high current loads continuous discharge rates 15 30 amps SR Max Pack cells best choice rather Magnum cells addition Electric Flight battery packs SR now Stop source Electric Flight supplies SR now stocks motors props chargers wire connectors switches just about anything else might need Electric Flight addition everyone SR will too happy answer questions help solve problems might have place order ask question can reach us calling Hotline 516-286-0079 between 9am 5pm Monday through Friday youd like us send literature send self addressed business size envelope 50 cents postage SR Batteries Inc Box 287 Bellport NY 11713 -ADVERTISEMENTsame principle involved Now area mean aerodynamic chord aerodynamic center location weird wing have determined can treated like ordinary wing calculation proper center-of-gravity location equation presented July 1988 column can used distance between aerodynamic centers wing horizontal stabilizer L well half horizontal stabilizer area ST two additional items must com puted order determine center-ofgravity should located aft wing aerody namic center equation used Equation 5 same equation July 1988 column Note Since found area mean aerodynamic chord aerodynamic center wing panel side air plane must use half horizontal sta bilizer area want use total stabilizer area double area wing panel just computed Got Next month plan discuss possible expedi tious way handling competition rule changes guarantee wont boring RC Giant Scale/de Vries Continued page 53 Five flight stations provided well covered pit area As usual safe flying name game werent midairs spectators well behind flight line According Bob lots Cubs P-47s P-51s well exotic models latter included all-metal 32lb beauty several twin-engined gas burners Sorry dont have photos big bash therell extensive coverage IMAAs High Flight sure Don Berliner aviation historian par excellence has advised us new organization devoted air racing history Its Society Air Racing Historians based Ohio correspondent has submitted application membership will pass along appropriate address other data know bit about organi zation What weve seen far looks very prom ising indeed As noted earlier column weve received Bert Thompsons quarter-scale drawings Benny Howards Ike Construction has begun sporty wheel pants Theyre 11 long holds two three-inch wheels along beam mechanism will keep everything aligned both air ground some very tricky wire bending involved comes landing gear struts lower ends soldered together along section big safety pin acts spring streamline pants airflow Next agenda make fiberglass cowl rest bird standard construction should breeze Fred Wallman process moving Minnesota retirement home Mesa AZ Before left northern climes assembled Ryan B-S photo session Hes bit ahead yours trulyhe has scale engine place wing struts assembled Ah wing leading edges finished Prolific model designer Don Neill 1120 So 40th St Lincoln NE 68510 has responded very positive way call Giant version Rudy Klings Folkerts SK-3 Actually Don way ahead comment Hes already fly ing prototype model Span model 66 fuselage 87 long Power new A&M Sachs 32 Don promises draw ings will available hes going install retracts Dennis Crooks has 1990 RC Scale Aircraft calendar ready Its another gemfantastic color photography want keep track days 90 contact DC Aviation PO Box 98 Big Rock IL 60511 Dennis will customize calendars club other organization takes credit cards Heres unabashed plug ViP Publishers Inc Dick Phillips yours trulys company now has Henry Haffkes masterful history Gran yule Brothers Gee Bee airplanes print title book Gee Bee REAL Story Granville Brothers Amazing Air planes Its first time author has co operation Granville family producing book about Thompson Trophy-winning rac ers early Thirties Bob Benjamin provided cover painting three- five-view drawings Gee Bee airplanes included soft-backed book Englands Harry Robinson US s Bill Hannan Henry located host photo graphs published before singu lar epic Henry Vein Clemens Williams Bros have published great Giant Scale drawings Gee Bee line aircraft book will come prime documentation source big-bird modelers Price Haffkes opus $2495 plus $200 P&H ViP Publishers Inc PO Box 16103 Colorado Springs CO 80935 December 1989 157