Objectives Criteria Success Test Specimen Test Setup Test Loads Test Procedure Instrumentation Data Requirements Objectives always hard define may start wanting something generic like safety much safety want want structure wont fail under reasonable loads whats reason able Make easy yourself specific Let first objective example perform static loading test wing structure will simulate symmetri cal wing bending caused maximum positive high angle attack maximum velocity Thats real flight condition can analyze basis design mission develop acceptable test loads test Let give example might designing Formula Pylon Racer go few races estimate maximum airspeed 150 mph turning radius 100 ft go home positive high angle attack maximum velocity test conditions mind Now sit down design test turn need know couple equations Centrifugal Force gr w weight pounds v velocity feet per second g leration gravity feet per second per second r ing radius feet 1467conversion factor mph feet per second Putting letters side side means multiplied diagonal line means divided notationvv means velocity multiplied itself squared can also written v2 Lift 1189vvS 4hqFLOW cL oil section lift coeffi cient apure number Swing ar square feet 001 189vv known dynamic pres sure q used calculate kinds aerodynamic forces case q 001189x150x1467x150x1467 576 lb/sq ft six-pound model moving 150 mph turning 100-ft radius will need F wvv/gr 150 x 1467 x 150 x 1467/322 x 100 ounds lift wing works out 1 5-G turn 90/6 ctually would need about 15% lift 1035 lb account down tail force making turn possible Based wing area 450/144 3125 ft works outto aliftof1035/3125 331 lb/sq ft get lift will need lift coefficientofcL 1035/576x3125 0575 airfoil data tells num ber reasonable could go high 14 An airplane high angle attack making lot drag slowing down plane might 150 mph straights has slow down turns Slowing down reduces dynamic pressure turn reduces lift have increase cL increasing angle attack numbers can increase cby factor three estimate turning radius may about right same data can estimate lift likely get 150 mph 14/575 x 1035 lb 806 lb/sq ft include wing area inside fuselage lifting area Look F-14 picture make own de cisions would include Continued page 163 I4 L1HJ2 cC 2W- 60/GO z 2180 60Mf1 cjLIS T 2180 /50 p4 Left generalized airfoil properties chart applicable model airplanes lot drag made high angle attack specific information see Theory Wing SectionsIncluding Summary Airfoil Data Dover Publications available Zenith Aviation Books Right Shown visualization addition gust vector affects local airflow model plane flight December 1986 65 photo F-i 4 6-G turn sucking moisture out air humid day taken TV screen Pratt & Whitney 60th Birthday Party High suction developed above airplane right plane view has reduced local air pressure thatof much higheraltitude clouds form picture shows way lifting pressures distributed over span aircraft Note halfelliptical shape near wing tips well contributions forward fuselage large area between engines / 3 AaiqIe AttOCk Realize Genuine Improvement RC Flying Geometron Transmitter Support Completely frees hands control sticks u Extremely comfortable use wear Put levers nothing way Allows concentrate ontake oft instant hat No belts flying because dont have hold transmitter whilebuckles straps no cord around neck operating controls Provides full four corner stickWearing support transmitter stays place mobilityyou carry plane Improves accuracy stick movement because Doubles ideal ground support offers perfect transmitter held stable accessibility keeps transmitter off ground Adjusts two-stick Tx modifications adapt- Ruggedly built heat treated aluminum finished able single stick Tx easy change support plate heavy duty anodize Assembled stainless Simple adjustments ann length shoulder size steel fasteners Deaigned constructed extended Transmitter secured safety catch can removed use 695O aced second yet cannot accidentally fall out PURCHASE ALL THREE ITEMS $995Q dealer order direct GEOMETRON CO INC 12 INGLESIDE ROAD LEXINGTON MA 02173 617 861-6526 SAVE $99Q PROVEN TO BE TREMENDOUS HELP FOR BOTH BEGINNERS AND EXPERTS! Plas $150 shipping COD 250 add5oshi cash stones order nero chatoes aoolo off Ia cononenha US Mass residena add 5% LCD TIMER/STOPWATCH Counts up down preset hold additive features Time out sounds alarm auto shut off Easy read outdoors lithium battery- 21 95* PROTECTIVE BAG Made spece age aluminum coated nylon Reflects suns heat protects Tx dirt dust special fast acting closure ONCE YOU USE IT YOU WILL NEVER FLY WITHOUT IT RC Pylon Racing/Hager Continued page 159 contest Sure weather will clear hope Well Mother Nature did cooperate cause rainy days field hadnt mowed grass reported Paul Zaleskas after extra trip field previous day least four inches long So after panic call Fay Harris quick mow job field good shape contest Thanks Fay time got field clouds disappeared just got course laid out some equipment place Fay came mowed grass good short Fifteen fliers hand start racing fourth heat first round yours truly mid-aired Jeff Faleo unfastened Jeffs right wing making somewhat difficult Jeff complete heat Sorry about No 1 though quite windy caused some real thrills everyone seemed have good time After dust settled engines ceased roaring ended follows 1 Bob Bently 2 Bob Loehner 3 Dan Kane 4 Dave Smith 5 Danny Kane Jr thanks club members nonmembers helped make contest success Thats month See races Bill Hager 706 Glen Haven Dr Conroe TX 77385 Structural Tests/Myers Continued page 65 Now does make sense design test around the 1035-lb figure should go 252 lb can limit maximum maneuvering lift limiting ele vator travel know Formula fliers Should go abrupt pullout terminal-velocity dive can estimate whole-body drag coefficient airplane knowing airplanes weight set weight equal drag find terminal velocity could 180 mph could produce maximum lift 363 lb figure out Down tail force point would about 55 lb de pending tail area tail moment arm airfoil etc Ask yourself Will air plane ever yanked about like will pilot smart enough ease out dive lower G Before answer let give another example Recently took over students 35-powered Cessna foamie up rather high engine quit put nose down gentle dive 200 300 nose down After plane traveled about 50 yd straight line saw wing tips yank up lots dihedral followed violent nose-up pitch airplane As speed built up adding down elevator keep path straight line Since wings held rubberbands seems likely wing lifted off fuselage precipitate pitch-up can see terminal velocity model both control- con figuration-dependent Now lets return question pilot continued feed more down elevator airplane would have pulled itself out dive much lower airspeed rubberbands NEW IMPROVED *flsr WUWIt Medd vim nuere weeli Pew. * WANDIT * USpoweNoDes * *Dealers moOed ______________________ * --- 5 * ImE1 *one eor warrarirhlCORD * *WetorDry *Stick Abrasives * * A Keen Machine gives esceptional 5 * sanding control eacellent tinish * *5955hasic mCi i hal Wand 1 each5 *vihgots5 *~555ffoilder Special vol 2 fiat 1 hair ivund wand 5 Oh 6 gvlS *1 29Deicce mncades 31101 2 hail roond5 *woods 1 hoff wands 10 itional Wands Abrasives available5 S * WANDIT MANUFACTURING 214 288-5789 * *PO Box 266 uite Texas 751495 stronger might have held dive higher velocity case some thing else would have happened possibly horizontal tail would have broken off bending downward Id inclined trust pilot par ticularly competent flight-test program planned future test pilot could carefully work up terminal velocity dive still concern about gusts plane might cross wake another racer traveling 150 mph could introduce sharp-edged vertical gust Tra ditionally gust velocity 40% forward velocity 04 x 150 ph would assuumed case would result instantaneous local velocity vector sum velocities 162 mph increase of2l80 angle attack airplane flying near 00 150 mph gust would increase angle attack beyond stall angle Therefore would expect see maxi mum lift due gusts 150 mph tells us should test 252-lb wing lift 38-lb down tail load Design loads problem see competent test engineer will look SiCil P5RPORM*5CR 0050 iou5tltieff CLlOEtt5 PROS REOEROCE Cash TWO ROLL SIZE Ponneess yOUR ceolcel iccosneanfo RoBRiCAnIOs *55 rLvisc ssneucTIOsS torn *OOivIOsOL POnOERnS $l 20 EOCS OR SIC PACE RiCE SO F7 5 RoouprBC54 Sirro December 1986 163 IMerry ChristmasI FABTRONICSI Make specially good flier whether flies 2 cycle 4 cycle CDI system will give better idle positive spark right time much less residue plane car boat etc plus fact makes cost fuel much less factor run engine pennies stead dollars Nearly engine can converted unit comes pre drilled disk sensor clamp mounting sensor engine 90 day warranty complete instructions con version timing procedure Unit operates 48 volt low current drain weight isa mere 2 oz size 2 x 2 x 75 inches Complete system comes ignition coil spark plug on/off switch igni tion cable also available seperately Bat teries included Please state engine size use ordering Installation very easy no special tools needed Automatic spark advance now available 4 cycle engines Complete System $6995 Cash MO certified check plus $300 P & H Personal checks take time clear Illinois residents please add tax Brochure $100 ndable purchase FABTRONICS 3751111 Rival Hi GaluSImuru III IlUl situation viewpoint worst possible combination events likely happen service attempt test thatcarefully Now Criteria Success What expect wing structure allowed crack long doesnt separate two pieces might concealed damage allowed crush dihedral increases easy change see measure Have designed something structure will yield breaking thus reveal overload Lee Renaud put -in-dia steel dowel wing root Aquila worked beautifully show overloads failing Total failure easy recognize Success may subtle test setup can simple have typical balsa-sheeted foam-core Pattern wing might able set up two sawhorses put pillows avoid crushing structure locally pile loads center section until satisfied other hand have Old-Timer wing lots skinny spars ribs may want spread load around bit carefully Again look F-14 picture idea distribute lift loads test loads themselves always pre sent problem After have designed airplane meet specific set conditions can sure have designed meet critical conditions will actually encounter service Simple swer cant have designed built flown crashed lot airplanes begin understand what works what doesnt keep records next design will always easier will constantly starting over designs will generally overweight well remember Sun-Fli 4-20 large maple block wing panel landing gear block sup ported edges several soft 1/16 balsa ribs tiny plywood doublers end wing sheeting around block blocks tore out time didnt wheels swung back punched through lower surface wing operating turf Du Bro wheels plans building instructions didnt say anything about installation might have satisfac tory flying off pavement flying off turf thinner wheels difficult find out what structure has designed what will withstand unless test Crash loads expect shed few parts crash Ideally primary struc ture should protect radio system engine much possible Thats good RC designs have lot plywood around radio compartment see Bob Aberle design US Navy says cockpit must protect pilot crash exerts 40-G forward 20-G downloads Should want test criteria could push down forward up back both items want test largest load would need would about 447 x 6 lb lb extension mount chainsaw engine Mounts 40 60size engines should resist about 50 lb radio tray four servos switch harness receiver battery must resist about 35 lb Servo rails must resist about 5 lb per servo Handling transportation cludes causes hangar rash Very little attention paid loads until plan pack ship aircraft Well come back later George M Myers 70 Froehlich Farm Rd Hicksville NY 11801 CL Aerobatics/Fancher Continued page 66 present extend token appreciation gratitude wish add printed thanks love Rev Id also like acknowledge help several people owe personal thanks Lou Dudka Glen Meador whipping up beautiful foam wing short notice two years ago found time complete spring Large James Greenaway man expertise greatly admire notwithstanding fact dont agree everything supplying modified hemi-head used good advantage ST 46 smoother economical stock squish-band head slight loss power especially good friends Gary McClellan Don McClave both qualified finals themselves gave unselfishiy expertise support became clear would competing top prize Thanks Last certainly least Thank kind enough call write congratulations thoughtfulness greatly appreciated thought might interesting relate TME DIFFERENT FOAM MODEL ILowest Cost Med sing Send $100 latest fine-grain sheet foam I developments foam samples FREE foam 3 sources Hard Shell finishes now LIable Dozens easy build foam air plane plans Peanuts RIC FOAM SCALE MODELS SS2MA St Croix Falls WI 84024 164Model Aviation IMPORTED DIESELS A-UAurorsD-CEDMVVSMUtsEnyS PAWTspIln Standard R/C.0864S Acre & Marine VlntageSpert eat Send *100 InformatIon CARLSON ENGINE IMPORTS 814 East Marconi Phoeiilx AZ 85022 WORLOS BIOGES SCALE PHOTO SERVICE 500 PHOTO RECKS PLANS EWS PHOTO-PACKSPLANS CNLARGING CASE E-ISglng CO Catalog S3O0 SCALE PLANS PHOTO SERVICE 3209 Mednon Gepsboo NC 27403 Phone 19152925239 No COIIOCI couple factors proved instrumental victory year First selected tactical approach achieving goal second learned valuable lesson about making engines work As reported two months ago experiment Enya four-stroke proved fruitless left brand new alrplane very good flier weighed 59 ozon ragged edge too heavy basically-stock ST 46s alrplane capable flying some precise maneuvers long wasnt pressed too hard After couple practice sessions Don Gary decided alrplane could consistently fly fairly high-scoring maneuvers 32- 35-point rangebut pushed fly really hard corners super-small maneuvers search another point two would inevit ably cause blow couple maneuvers badly Unfortunately has experience couple poor maneuvers pattern will adversely affect scores others well could really nail couple maneuvers overall score would suffer result obviously poor ones night before qualifying decided plan action would fly conservatively try give judges obvious reasons socking would fly no smaller no tighter no faster confident flying well 99% time Although flew few wowwww maneuvers during entire week also flew awwwwful maneu ver results speak themselves moral story take stock assets debits going competition devise game plan based evaluation Size up competition equipment physical condition weather Set real istic goal local champ goal quite honestly will likely embar rass yourself should probably fly con servatively avoid opening doors upand-coming hotshots fly through other hand up and-comers have very little lose letting hang out within honest limits your equipments ability Avoid trying change style accommodate some perceived pre ference part judges perception correct chance successfully changing style couple flights ranges slim Continue good job showing judge what doesnt like return fly another daywith luck itll front discerning judge Engines Over last 10 years have become pretty well-known inconsistent en gine runs ST 46s year ran like clocks week long Did find secret ask Well think found Give try major problem has always getting engine would run same speed entire tankflight after flight after flight Also needle valves incredibly sensitivethe tiniest adjustment making large changes always expected direction would get occasional good run among variety too slow too fast ones until after anywhere maybe 50 flights engine would simply break two-cycle couple laps after takeoff stay flew entire 1984 Walker Flyoff Reno dead two-cycle very reason Shortly before years Nats began have problem again started usual fix rearranging praying Upon disassembly however noticed dlscoloration several places side piston below ring color matched blue hue fuel using classic indlcation blowby condition seal between ring cylinder wall broken explosive charge escapes combustion chamber thereby re ducing cylinder pressure output torque engine temporarily reassembled piston cylinder sleeve noticed areas discoloration occurred piston corre sponded areas cylinder walls polished appearance two pieces evidence got old think tank cranked up conclusions fix knock wood has proved 100% successful point What feel happening could likened hydroplaning phenomenon occurs tire running surface covered water some point depending velocity tire pressure layer water builds up between tire road surface contact tween two lost resulting loss ability control direction tire inability stop vehicle tire mounted Hydroplaning significant problem instance attempting stop heavy air liner wet runway Obviously slick tire much suscepti ble hydroplaning tread ever hydroplaning can problem treaded tires too solution has employed full-scale aviation has cut grooves surface runways combination treaded tires grooved runway effectively eliminates hydroplaning allowing com pressed water place dissipate theory piston ring will effect hydroplane layer oil over highlypolished areas cylinder wall destroying seal consequently reducing cylinder pressure necessary consistent fourcycle operation two-cycle engine results erratic super-sensitive-to-the-needle speed-stunt Tigres fix consists purchasing inexpensive brake cylinder hone automotive parts store chucking up cheapie drill press running slowest possible speed hone cylinder walls until uniformly dull appearance approximate crosshatch pat tern tiny scratches made cylinder hone act like grooves runway allowing oil December 1986 165 ziJ f7 N 0 Co 0 x ih 0 x N Co CD 1 I m z 0 z z C, 0 -a 0 -a m I m 0 0 0 0 -1 CD C 0 0 CD 6 0 Co 0 0 01 0 WORLD Vacation Handy Disney World Kennedy Space Center rest Florida 3 Bedrooms sleeps 8 Kitchen A/C Pool Tennis lots B/C flying Nov-May $500 wk / Jane-Oct 0480 wk / nightly & nssnthly rates also available 617 528-4043 P AW DIESELS Englands Finest 049 35 RIC STD Sud $100 list Eric Clutton 913 Cedar Lane Tullahoma Tenn 37388
Edition: Model Aviation - 1986/12
Page Numbers: 65, 163, 164, 165
Objectives Criteria Success Test Specimen Test Setup Test Loads Test Procedure Instrumentation Data Requirements Objectives always hard define may start wanting something generic like safety much safety want want structure wont fail under reasonable loads whats reason able Make easy yourself specific Let first objective example perform static loading test wing structure will simulate symmetri cal wing bending caused maximum positive high angle attack maximum velocity Thats real flight condition can analyze basis design mission develop acceptable test loads test Let give example might designing Formula Pylon Racer go few races estimate maximum airspeed 150 mph turning radius 100 ft go home positive high angle attack maximum velocity test conditions mind Now sit down design test turn need know couple equations Centrifugal Force gr w weight pounds v velocity feet per second g leration gravity feet per second per second r ing radius feet 1467conversion factor mph feet per second Putting letters side side means multiplied diagonal line means divided notationvv means velocity multiplied itself squared can also written v2 Lift 1189vvS 4hqFLOW cL oil section lift coeffi cient apure number Swing ar square feet 001 189vv known dynamic pres sure q used calculate kinds aerodynamic forces case q 001189x150x1467x150x1467 576 lb/sq ft six-pound model moving 150 mph turning 100-ft radius will need F wvv/gr 150 x 1467 x 150 x 1467/322 x 100 ounds lift wing works out 1 5-G turn 90/6 ctually would need about 15% lift 1035 lb account down tail force making turn possible Based wing area 450/144 3125 ft works outto aliftof1035/3125 331 lb/sq ft get lift will need lift coefficientofcL 1035/576x3125 0575 airfoil data tells num ber reasonable could go high 14 An airplane high angle attack making lot drag slowing down plane might 150 mph straights has slow down turns Slowing down reduces dynamic pressure turn reduces lift have increase cL increasing angle attack numbers can increase cby factor three estimate turning radius may about right same data can estimate lift likely get 150 mph 14/575 x 1035 lb 806 lb/sq ft include wing area inside fuselage lifting area Look F-14 picture make own de cisions would include Continued page 163 I4 L1HJ2 cC 2W- 60/GO z 2180 60Mf1 cjLIS T 2180 /50 p4 Left generalized airfoil properties chart applicable model airplanes lot drag made high angle attack specific information see Theory Wing SectionsIncluding Summary Airfoil Data Dover Publications available Zenith Aviation Books Right Shown visualization addition gust vector affects local airflow model plane flight December 1986 65 photo F-i 4 6-G turn sucking moisture out air humid day taken TV screen Pratt & Whitney 60th Birthday Party High suction developed above airplane right plane view has reduced local air pressure thatof much higheraltitude clouds form picture shows way lifting pressures distributed over span aircraft Note halfelliptical shape near wing tips well contributions forward fuselage large area between engines / 3 AaiqIe AttOCk Realize Genuine Improvement RC Flying Geometron Transmitter Support Completely frees hands control sticks u Extremely comfortable use wear Put levers nothing way Allows concentrate ontake oft instant hat No belts flying because dont have hold transmitter whilebuckles straps no cord around neck operating controls Provides full four corner stickWearing support transmitter stays place mobilityyou carry plane Improves accuracy stick movement because Doubles ideal ground support offers perfect transmitter held stable accessibility keeps transmitter off ground Adjusts two-stick Tx modifications adapt- Ruggedly built heat treated aluminum finished able single stick Tx easy change support plate heavy duty anodize Assembled stainless Simple adjustments ann length shoulder size steel fasteners Deaigned constructed extended Transmitter secured safety catch can removed use 695O aced second yet cannot accidentally fall out PURCHASE ALL THREE ITEMS $995Q dealer order direct GEOMETRON CO INC 12 INGLESIDE ROAD LEXINGTON MA 02173 617 861-6526 SAVE $99Q PROVEN TO BE TREMENDOUS HELP FOR BOTH BEGINNERS AND EXPERTS! Plas $150 shipping COD 250 add5oshi cash stones order nero chatoes aoolo off Ia cononenha US Mass residena add 5% LCD TIMER/STOPWATCH Counts up down preset hold additive features Time out sounds alarm auto shut off Easy read outdoors lithium battery- 21 95* PROTECTIVE BAG Made spece age aluminum coated nylon Reflects suns heat protects Tx dirt dust special fast acting closure ONCE YOU USE IT YOU WILL NEVER FLY WITHOUT IT RC Pylon Racing/Hager Continued page 159 contest Sure weather will clear hope Well Mother Nature did cooperate cause rainy days field hadnt mowed grass reported Paul Zaleskas after extra trip field previous day least four inches long So after panic call Fay Harris quick mow job field good shape contest Thanks Fay time got field clouds disappeared just got course laid out some equipment place Fay came mowed grass good short Fifteen fliers hand start racing fourth heat first round yours truly mid-aired Jeff Faleo unfastened Jeffs right wing making somewhat difficult Jeff complete heat Sorry about No 1 though quite windy caused some real thrills everyone seemed have good time After dust settled engines ceased roaring ended follows 1 Bob Bently 2 Bob Loehner 3 Dan Kane 4 Dave Smith 5 Danny Kane Jr thanks club members nonmembers helped make contest success Thats month See races Bill Hager 706 Glen Haven Dr Conroe TX 77385 Structural Tests/Myers Continued page 65 Now does make sense design test around the 1035-lb figure should go 252 lb can limit maximum maneuvering lift limiting ele vator travel know Formula fliers Should go abrupt pullout terminal-velocity dive can estimate whole-body drag coefficient airplane knowing airplanes weight set weight equal drag find terminal velocity could 180 mph could produce maximum lift 363 lb figure out Down tail force point would about 55 lb de pending tail area tail moment arm airfoil etc Ask yourself Will air plane ever yanked about like will pilot smart enough ease out dive lower G Before answer let give another example Recently took over students 35-powered Cessna foamie up rather high engine quit put nose down gentle dive 200 300 nose down After plane traveled about 50 yd straight line saw wing tips yank up lots dihedral followed violent nose-up pitch airplane As speed built up adding down elevator keep path straight line Since wings held rubberbands seems likely wing lifted off fuselage precipitate pitch-up can see terminal velocity model both control- con figuration-dependent Now lets return question pilot continued feed more down elevator airplane would have pulled itself out dive much lower airspeed rubberbands NEW IMPROVED *flsr WUWIt Medd vim nuere weeli Pew. * WANDIT * USpoweNoDes * *Dealers moOed ______________________ * --- 5 * ImE1 *one eor warrarirhlCORD * *WetorDry *Stick Abrasives * * A Keen Machine gives esceptional 5 * sanding control eacellent tinish * *5955hasic mCi i hal Wand 1 each5 *vihgots5 *~555ffoilder Special vol 2 fiat 1 hair ivund wand 5 Oh 6 gvlS *1 29Deicce mncades 31101 2 hail roond5 *woods 1 hoff wands 10 itional Wands Abrasives available5 S * WANDIT MANUFACTURING 214 288-5789 * *PO Box 266 uite Texas 751495 stronger might have held dive higher velocity case some thing else would have happened possibly horizontal tail would have broken off bending downward Id inclined trust pilot par ticularly competent flight-test program planned future test pilot could carefully work up terminal velocity dive still concern about gusts plane might cross wake another racer traveling 150 mph could introduce sharp-edged vertical gust Tra ditionally gust velocity 40% forward velocity 04 x 150 ph would assuumed case would result instantaneous local velocity vector sum velocities 162 mph increase of2l80 angle attack airplane flying near 00 150 mph gust would increase angle attack beyond stall angle Therefore would expect see maxi mum lift due gusts 150 mph tells us should test 252-lb wing lift 38-lb down tail load Design loads problem see competent test engineer will look SiCil P5RPORM*5CR 0050 iou5tltieff CLlOEtt5 PROS REOEROCE Cash TWO ROLL SIZE Ponneess yOUR ceolcel iccosneanfo RoBRiCAnIOs *55 rLvisc ssneucTIOsS torn *OOivIOsOL POnOERnS $l 20 EOCS OR SIC PACE RiCE SO F7 5 RoouprBC54 Sirro December 1986 163 IMerry ChristmasI FABTRONICSI Make specially good flier whether flies 2 cycle 4 cycle CDI system will give better idle positive spark right time much less residue plane car boat etc plus fact makes cost fuel much less factor run engine pennies stead dollars Nearly engine can converted unit comes pre drilled disk sensor clamp mounting sensor engine 90 day warranty complete instructions con version timing procedure Unit operates 48 volt low current drain weight isa mere 2 oz size 2 x 2 x 75 inches Complete system comes ignition coil spark plug on/off switch igni tion cable also available seperately Bat teries included Please state engine size use ordering Installation very easy no special tools needed Automatic spark advance now available 4 cycle engines Complete System $6995 Cash MO certified check plus $300 P & H Personal checks take time clear Illinois residents please add tax Brochure $100 ndable purchase FABTRONICS 3751111 Rival Hi GaluSImuru III IlUl situation viewpoint worst possible combination events likely happen service attempt test thatcarefully Now Criteria Success What expect wing structure allowed crack long doesnt separate two pieces might concealed damage allowed crush dihedral increases easy change see measure Have designed something structure will yield breaking thus reveal overload Lee Renaud put -in-dia steel dowel wing root Aquila worked beautifully show overloads failing Total failure easy recognize Success may subtle test setup can simple have typical balsa-sheeted foam-core Pattern wing might able set up two sawhorses put pillows avoid crushing structure locally pile loads center section until satisfied other hand have Old-Timer wing lots skinny spars ribs may want spread load around bit carefully Again look F-14 picture idea distribute lift loads test loads themselves always pre sent problem After have designed airplane meet specific set conditions can sure have designed meet critical conditions will actually encounter service Simple swer cant have designed built flown crashed lot airplanes begin understand what works what doesnt keep records next design will always easier will constantly starting over designs will generally overweight well remember Sun-Fli 4-20 large maple block wing panel landing gear block sup ported edges several soft 1/16 balsa ribs tiny plywood doublers end wing sheeting around block blocks tore out time didnt wheels swung back punched through lower surface wing operating turf Du Bro wheels plans building instructions didnt say anything about installation might have satisfac tory flying off pavement flying off turf thinner wheels difficult find out what structure has designed what will withstand unless test Crash loads expect shed few parts crash Ideally primary struc ture should protect radio system engine much possible Thats good RC designs have lot plywood around radio compartment see Bob Aberle design US Navy says cockpit must protect pilot crash exerts 40-G forward 20-G downloads Should want test criteria could push down forward up back both items want test largest load would need would about 447 x 6 lb lb extension mount chainsaw engine Mounts 40 60size engines should resist about 50 lb radio tray four servos switch harness receiver battery must resist about 35 lb Servo rails must resist about 5 lb per servo Handling transportation cludes causes hangar rash Very little attention paid loads until plan pack ship aircraft Well come back later George M Myers 70 Froehlich Farm Rd Hicksville NY 11801 CL Aerobatics/Fancher Continued page 66 present extend token appreciation gratitude wish add printed thanks love Rev Id also like acknowledge help several people owe personal thanks Lou Dudka Glen Meador whipping up beautiful foam wing short notice two years ago found time complete spring Large James Greenaway man expertise greatly admire notwithstanding fact dont agree everything supplying modified hemi-head used good advantage ST 46 smoother economical stock squish-band head slight loss power especially good friends Gary McClellan Don McClave both qualified finals themselves gave unselfishiy expertise support became clear would competing top prize Thanks Last certainly least Thank kind enough call write congratulations thoughtfulness greatly appreciated thought might interesting relate TME DIFFERENT FOAM MODEL ILowest Cost Med sing Send $100 latest fine-grain sheet foam I developments foam samples FREE foam 3 sources Hard Shell finishes now LIable Dozens easy build foam air plane plans Peanuts RIC FOAM SCALE MODELS SS2MA St Croix Falls WI 84024 164Model Aviation IMPORTED DIESELS A-UAurorsD-CEDMVVSMUtsEnyS PAWTspIln Standard R/C.0864S Acre & Marine VlntageSpert eat Send *100 InformatIon CARLSON ENGINE IMPORTS 814 East Marconi Phoeiilx AZ 85022 WORLOS BIOGES SCALE PHOTO SERVICE 500 PHOTO RECKS PLANS EWS PHOTO-PACKSPLANS CNLARGING CASE E-ISglng CO Catalog S3O0 SCALE PLANS PHOTO SERVICE 3209 Mednon Gepsboo NC 27403 Phone 19152925239 No COIIOCI couple factors proved instrumental victory year First selected tactical approach achieving goal second learned valuable lesson about making engines work As reported two months ago experiment Enya four-stroke proved fruitless left brand new alrplane very good flier weighed 59 ozon ragged edge too heavy basically-stock ST 46s alrplane capable flying some precise maneuvers long wasnt pressed too hard After couple practice sessions Don Gary decided alrplane could consistently fly fairly high-scoring maneuvers 32- 35-point rangebut pushed fly really hard corners super-small maneuvers search another point two would inevit ably cause blow couple maneuvers badly Unfortunately has experience couple poor maneuvers pattern will adversely affect scores others well could really nail couple maneuvers overall score would suffer result obviously poor ones night before qualifying decided plan action would fly conservatively try give judges obvious reasons socking would fly no smaller no tighter no faster confident flying well 99% time Although flew few wowwww maneuvers during entire week also flew awwwwful maneu ver results speak themselves moral story take stock assets debits going competition devise game plan based evaluation Size up competition equipment physical condition weather Set real istic goal local champ goal quite honestly will likely embar rass yourself should probably fly con servatively avoid opening doors upand-coming hotshots fly through other hand up and-comers have very little lose letting hang out within honest limits your equipments ability Avoid trying change style accommodate some perceived pre ference part judges perception correct chance successfully changing style couple flights ranges slim Continue good job showing judge what doesnt like return fly another daywith luck itll front discerning judge Engines Over last 10 years have become pretty well-known inconsistent en gine runs ST 46s year ran like clocks week long Did find secret ask Well think found Give try major problem has always getting engine would run same speed entire tankflight after flight after flight Also needle valves incredibly sensitivethe tiniest adjustment making large changes always expected direction would get occasional good run among variety too slow too fast ones until after anywhere maybe 50 flights engine would simply break two-cycle couple laps after takeoff stay flew entire 1984 Walker Flyoff Reno dead two-cycle very reason Shortly before years Nats began have problem again started usual fix rearranging praying Upon disassembly however noticed dlscoloration several places side piston below ring color matched blue hue fuel using classic indlcation blowby condition seal between ring cylinder wall broken explosive charge escapes combustion chamber thereby re ducing cylinder pressure output torque engine temporarily reassembled piston cylinder sleeve noticed areas discoloration occurred piston corre sponded areas cylinder walls polished appearance two pieces evidence got old think tank cranked up conclusions fix knock wood has proved 100% successful point What feel happening could likened hydroplaning phenomenon occurs tire running surface covered water some point depending velocity tire pressure layer water builds up between tire road surface contact tween two lost resulting loss ability control direction tire inability stop vehicle tire mounted Hydroplaning significant problem instance attempting stop heavy air liner wet runway Obviously slick tire much suscepti ble hydroplaning tread ever hydroplaning can problem treaded tires too solution has employed full-scale aviation has cut grooves surface runways combination treaded tires grooved runway effectively eliminates hydroplaning allowing com pressed water place dissipate theory piston ring will effect hydroplane layer oil over highlypolished areas cylinder wall destroying seal consequently reducing cylinder pressure necessary consistent fourcycle operation two-cycle engine results erratic super-sensitive-to-the-needle speed-stunt Tigres fix consists purchasing inexpensive brake cylinder hone automotive parts store chucking up cheapie drill press running slowest possible speed hone cylinder walls until uniformly dull appearance approximate crosshatch pat tern tiny scratches made cylinder hone act like grooves runway allowing oil December 1986 165 ziJ f7 N 0 Co 0 x ih 0 x N Co CD 1 I m z 0 z z C, 0 -a 0 -a m I m 0 0 0 0 -1 CD C 0 0 CD 6 0 Co 0 0 01 0 WORLD Vacation Handy Disney World Kennedy Space Center rest Florida 3 Bedrooms sleeps 8 Kitchen A/C Pool Tennis lots B/C flying Nov-May $500 wk / Jane-Oct 0480 wk / nightly & nssnthly rates also available 617 528-4043 P AW DIESELS Englands Finest 049 35 RIC STD Sud $100 list Eric Clutton 913 Cedar Lane Tullahoma Tenn 37388
Edition: Model Aviation - 1986/12
Page Numbers: 65, 163, 164, 165
Objectives Criteria Success Test Specimen Test Setup Test Loads Test Procedure Instrumentation Data Requirements Objectives always hard define may start wanting something generic like safety much safety want want structure wont fail under reasonable loads whats reason able Make easy yourself specific Let first objective example perform static loading test wing structure will simulate symmetri cal wing bending caused maximum positive high angle attack maximum velocity Thats real flight condition can analyze basis design mission develop acceptable test loads test Let give example might designing Formula Pylon Racer go few races estimate maximum airspeed 150 mph turning radius 100 ft go home positive high angle attack maximum velocity test conditions mind Now sit down design test turn need know couple equations Centrifugal Force gr w weight pounds v velocity feet per second g leration gravity feet per second per second r ing radius feet 1467conversion factor mph feet per second Putting letters side side means multiplied diagonal line means divided notationvv means velocity multiplied itself squared can also written v2 Lift 1189vvS 4hqFLOW cL oil section lift coeffi cient apure number Swing ar square feet 001 189vv known dynamic pres sure q used calculate kinds aerodynamic forces case q 001189x150x1467x150x1467 576 lb/sq ft six-pound model moving 150 mph turning 100-ft radius will need F wvv/gr 150 x 1467 x 150 x 1467/322 x 100 ounds lift wing works out 1 5-G turn 90/6 ctually would need about 15% lift 1035 lb account down tail force making turn possible Based wing area 450/144 3125 ft works outto aliftof1035/3125 331 lb/sq ft get lift will need lift coefficientofcL 1035/576x3125 0575 airfoil data tells num ber reasonable could go high 14 An airplane high angle attack making lot drag slowing down plane might 150 mph straights has slow down turns Slowing down reduces dynamic pressure turn reduces lift have increase cL increasing angle attack numbers can increase cby factor three estimate turning radius may about right same data can estimate lift likely get 150 mph 14/575 x 1035 lb 806 lb/sq ft include wing area inside fuselage lifting area Look F-14 picture make own de cisions would include Continued page 163 I4 L1HJ2 cC 2W- 60/GO z 2180 60Mf1 cjLIS T 2180 /50 p4 Left generalized airfoil properties chart applicable model airplanes lot drag made high angle attack specific information see Theory Wing SectionsIncluding Summary Airfoil Data Dover Publications available Zenith Aviation Books Right Shown visualization addition gust vector affects local airflow model plane flight December 1986 65 photo F-i 4 6-G turn sucking moisture out air humid day taken TV screen Pratt & Whitney 60th Birthday Party High suction developed above airplane right plane view has reduced local air pressure thatof much higheraltitude clouds form picture shows way lifting pressures distributed over span aircraft Note halfelliptical shape near wing tips well contributions forward fuselage large area between engines / 3 AaiqIe AttOCk Realize Genuine Improvement RC Flying Geometron Transmitter Support Completely frees hands control sticks u Extremely comfortable use wear Put levers nothing way Allows concentrate ontake oft instant hat No belts flying because dont have hold transmitter whilebuckles straps no cord around neck operating controls Provides full four corner stickWearing support transmitter stays place mobilityyou carry plane Improves accuracy stick movement because Doubles ideal ground support offers perfect transmitter held stable accessibility keeps transmitter off ground Adjusts two-stick Tx modifications adapt- Ruggedly built heat treated aluminum finished able single stick Tx easy change support plate heavy duty anodize Assembled stainless Simple adjustments ann length shoulder size steel fasteners Deaigned constructed extended Transmitter secured safety catch can removed use 695O aced second yet cannot accidentally fall out PURCHASE ALL THREE ITEMS $995Q dealer order direct GEOMETRON CO INC 12 INGLESIDE ROAD LEXINGTON MA 02173 617 861-6526 SAVE $99Q PROVEN TO BE TREMENDOUS HELP FOR BOTH BEGINNERS AND EXPERTS! Plas $150 shipping COD 250 add5oshi cash stones order nero chatoes aoolo off Ia cononenha US Mass residena add 5% LCD TIMER/STOPWATCH Counts up down preset hold additive features Time out sounds alarm auto shut off Easy read outdoors lithium battery- 21 95* PROTECTIVE BAG Made spece age aluminum coated nylon Reflects suns heat protects Tx dirt dust special fast acting closure ONCE YOU USE IT YOU WILL NEVER FLY WITHOUT IT RC Pylon Racing/Hager Continued page 159 contest Sure weather will clear hope Well Mother Nature did cooperate cause rainy days field hadnt mowed grass reported Paul Zaleskas after extra trip field previous day least four inches long So after panic call Fay Harris quick mow job field good shape contest Thanks Fay time got field clouds disappeared just got course laid out some equipment place Fay came mowed grass good short Fifteen fliers hand start racing fourth heat first round yours truly mid-aired Jeff Faleo unfastened Jeffs right wing making somewhat difficult Jeff complete heat Sorry about No 1 though quite windy caused some real thrills everyone seemed have good time After dust settled engines ceased roaring ended follows 1 Bob Bently 2 Bob Loehner 3 Dan Kane 4 Dave Smith 5 Danny Kane Jr thanks club members nonmembers helped make contest success Thats month See races Bill Hager 706 Glen Haven Dr Conroe TX 77385 Structural Tests/Myers Continued page 65 Now does make sense design test around the 1035-lb figure should go 252 lb can limit maximum maneuvering lift limiting ele vator travel know Formula fliers Should go abrupt pullout terminal-velocity dive can estimate whole-body drag coefficient airplane knowing airplanes weight set weight equal drag find terminal velocity could 180 mph could produce maximum lift 363 lb figure out Down tail force point would about 55 lb de pending tail area tail moment arm airfoil etc Ask yourself Will air plane ever yanked about like will pilot smart enough ease out dive lower G Before answer let give another example Recently took over students 35-powered Cessna foamie up rather high engine quit put nose down gentle dive 200 300 nose down After plane traveled about 50 yd straight line saw wing tips yank up lots dihedral followed violent nose-up pitch airplane As speed built up adding down elevator keep path straight line Since wings held rubberbands seems likely wing lifted off fuselage precipitate pitch-up can see terminal velocity model both control- con figuration-dependent Now lets return question pilot continued feed more down elevator airplane would have pulled itself out dive much lower airspeed rubberbands NEW IMPROVED *flsr WUWIt Medd vim nuere weeli Pew. * WANDIT * USpoweNoDes * *Dealers moOed ______________________ * --- 5 * ImE1 *one eor warrarirhlCORD * *WetorDry *Stick Abrasives * * A Keen Machine gives esceptional 5 * sanding control eacellent tinish * *5955hasic mCi i hal Wand 1 each5 *vihgots5 *~555ffoilder Special vol 2 fiat 1 hair ivund wand 5 Oh 6 gvlS *1 29Deicce mncades 31101 2 hail roond5 *woods 1 hoff wands 10 itional Wands Abrasives available5 S * WANDIT MANUFACTURING 214 288-5789 * *PO Box 266 uite Texas 751495 stronger might have held dive higher velocity case some thing else would have happened possibly horizontal tail would have broken off bending downward Id inclined trust pilot par ticularly competent flight-test program planned future test pilot could carefully work up terminal velocity dive still concern about gusts plane might cross wake another racer traveling 150 mph could introduce sharp-edged vertical gust Tra ditionally gust velocity 40% forward velocity 04 x 150 ph would assuumed case would result instantaneous local velocity vector sum velocities 162 mph increase of2l80 angle attack airplane flying near 00 150 mph gust would increase angle attack beyond stall angle Therefore would expect see maxi mum lift due gusts 150 mph tells us should test 252-lb wing lift 38-lb down tail load Design loads problem see competent test engineer will look SiCil P5RPORM*5CR 0050 iou5tltieff CLlOEtt5 PROS REOEROCE Cash TWO ROLL SIZE Ponneess yOUR ceolcel iccosneanfo RoBRiCAnIOs *55 rLvisc ssneucTIOsS torn *OOivIOsOL POnOERnS $l 20 EOCS OR SIC PACE RiCE SO F7 5 RoouprBC54 Sirro December 1986 163 IMerry ChristmasI FABTRONICSI Make specially good flier whether flies 2 cycle 4 cycle CDI system will give better idle positive spark right time much less residue plane car boat etc plus fact makes cost fuel much less factor run engine pennies stead dollars Nearly engine can converted unit comes pre drilled disk sensor clamp mounting sensor engine 90 day warranty complete instructions con version timing procedure Unit operates 48 volt low current drain weight isa mere 2 oz size 2 x 2 x 75 inches Complete system comes ignition coil spark plug on/off switch igni tion cable also available seperately Bat teries included Please state engine size use ordering Installation very easy no special tools needed Automatic spark advance now available 4 cycle engines Complete System $6995 Cash MO certified check plus $300 P & H Personal checks take time clear Illinois residents please add tax Brochure $100 ndable purchase FABTRONICS 3751111 Rival Hi GaluSImuru III IlUl situation viewpoint worst possible combination events likely happen service attempt test thatcarefully Now Criteria Success What expect wing structure allowed crack long doesnt separate two pieces might concealed damage allowed crush dihedral increases easy change see measure Have designed something structure will yield breaking thus reveal overload Lee Renaud put -in-dia steel dowel wing root Aquila worked beautifully show overloads failing Total failure easy recognize Success may subtle test setup can simple have typical balsa-sheeted foam-core Pattern wing might able set up two sawhorses put pillows avoid crushing structure locally pile loads center section until satisfied other hand have Old-Timer wing lots skinny spars ribs may want spread load around bit carefully Again look F-14 picture idea distribute lift loads test loads themselves always pre sent problem After have designed airplane meet specific set conditions can sure have designed meet critical conditions will actually encounter service Simple swer cant have designed built flown crashed lot airplanes begin understand what works what doesnt keep records next design will always easier will constantly starting over designs will generally overweight well remember Sun-Fli 4-20 large maple block wing panel landing gear block sup ported edges several soft 1/16 balsa ribs tiny plywood doublers end wing sheeting around block blocks tore out time didnt wheels swung back punched through lower surface wing operating turf Du Bro wheels plans building instructions didnt say anything about installation might have satisfac tory flying off pavement flying off turf thinner wheels difficult find out what structure has designed what will withstand unless test Crash loads expect shed few parts crash Ideally primary struc ture should protect radio system engine much possible Thats good RC designs have lot plywood around radio compartment see Bob Aberle design US Navy says cockpit must protect pilot crash exerts 40-G forward 20-G downloads Should want test criteria could push down forward up back both items want test largest load would need would about 447 x 6 lb lb extension mount chainsaw engine Mounts 40 60size engines should resist about 50 lb radio tray four servos switch harness receiver battery must resist about 35 lb Servo rails must resist about 5 lb per servo Handling transportation cludes causes hangar rash Very little attention paid loads until plan pack ship aircraft Well come back later George M Myers 70 Froehlich Farm Rd Hicksville NY 11801 CL Aerobatics/Fancher Continued page 66 present extend token appreciation gratitude wish add printed thanks love Rev Id also like acknowledge help several people owe personal thanks Lou Dudka Glen Meador whipping up beautiful foam wing short notice two years ago found time complete spring Large James Greenaway man expertise greatly admire notwithstanding fact dont agree everything supplying modified hemi-head used good advantage ST 46 smoother economical stock squish-band head slight loss power especially good friends Gary McClellan Don McClave both qualified finals themselves gave unselfishiy expertise support became clear would competing top prize Thanks Last certainly least Thank kind enough call write congratulations thoughtfulness greatly appreciated thought might interesting relate TME DIFFERENT FOAM MODEL ILowest Cost Med sing Send $100 latest fine-grain sheet foam I developments foam samples FREE foam 3 sources Hard Shell finishes now LIable Dozens easy build foam air plane plans Peanuts RIC FOAM SCALE MODELS SS2MA St Croix Falls WI 84024 164Model Aviation IMPORTED DIESELS A-UAurorsD-CEDMVVSMUtsEnyS PAWTspIln Standard R/C.0864S Acre & Marine VlntageSpert eat Send *100 InformatIon CARLSON ENGINE IMPORTS 814 East Marconi Phoeiilx AZ 85022 WORLOS BIOGES SCALE PHOTO SERVICE 500 PHOTO RECKS PLANS EWS PHOTO-PACKSPLANS CNLARGING CASE E-ISglng CO Catalog S3O0 SCALE PLANS PHOTO SERVICE 3209 Mednon Gepsboo NC 27403 Phone 19152925239 No COIIOCI couple factors proved instrumental victory year First selected tactical approach achieving goal second learned valuable lesson about making engines work As reported two months ago experiment Enya four-stroke proved fruitless left brand new alrplane very good flier weighed 59 ozon ragged edge too heavy basically-stock ST 46s alrplane capable flying some precise maneuvers long wasnt pressed too hard After couple practice sessions Don Gary decided alrplane could consistently fly fairly high-scoring maneuvers 32- 35-point rangebut pushed fly really hard corners super-small maneuvers search another point two would inevit ably cause blow couple maneuvers badly Unfortunately has experience couple poor maneuvers pattern will adversely affect scores others well could really nail couple maneuvers overall score would suffer result obviously poor ones night before qualifying decided plan action would fly conservatively try give judges obvious reasons socking would fly no smaller no tighter no faster confident flying well 99% time Although flew few wowwww maneuvers during entire week also flew awwwwful maneu ver results speak themselves moral story take stock assets debits going competition devise game plan based evaluation Size up competition equipment physical condition weather Set real istic goal local champ goal quite honestly will likely embar rass yourself should probably fly con servatively avoid opening doors upand-coming hotshots fly through other hand up and-comers have very little lose letting hang out within honest limits your equipments ability Avoid trying change style accommodate some perceived pre ference part judges perception correct chance successfully changing style couple flights ranges slim Continue good job showing judge what doesnt like return fly another daywith luck itll front discerning judge Engines Over last 10 years have become pretty well-known inconsistent en gine runs ST 46s year ran like clocks week long Did find secret ask Well think found Give try major problem has always getting engine would run same speed entire tankflight after flight after flight Also needle valves incredibly sensitivethe tiniest adjustment making large changes always expected direction would get occasional good run among variety too slow too fast ones until after anywhere maybe 50 flights engine would simply break two-cycle couple laps after takeoff stay flew entire 1984 Walker Flyoff Reno dead two-cycle very reason Shortly before years Nats began have problem again started usual fix rearranging praying Upon disassembly however noticed dlscoloration several places side piston below ring color matched blue hue fuel using classic indlcation blowby condition seal between ring cylinder wall broken explosive charge escapes combustion chamber thereby re ducing cylinder pressure output torque engine temporarily reassembled piston cylinder sleeve noticed areas discoloration occurred piston corre sponded areas cylinder walls polished appearance two pieces evidence got old think tank cranked up conclusions fix knock wood has proved 100% successful point What feel happening could likened hydroplaning phenomenon occurs tire running surface covered water some point depending velocity tire pressure layer water builds up between tire road surface contact tween two lost resulting loss ability control direction tire inability stop vehicle tire mounted Hydroplaning significant problem instance attempting stop heavy air liner wet runway Obviously slick tire much suscepti ble hydroplaning tread ever hydroplaning can problem treaded tires too solution has employed full-scale aviation has cut grooves surface runways combination treaded tires grooved runway effectively eliminates hydroplaning allowing com pressed water place dissipate theory piston ring will effect hydroplane layer oil over highlypolished areas cylinder wall destroying seal consequently reducing cylinder pressure necessary consistent fourcycle operation two-cycle engine results erratic super-sensitive-to-the-needle speed-stunt Tigres fix consists purchasing inexpensive brake cylinder hone automotive parts store chucking up cheapie drill press running slowest possible speed hone cylinder walls until uniformly dull appearance approximate crosshatch pat tern tiny scratches made cylinder hone act like grooves runway allowing oil December 1986 165 ziJ f7 N 0 Co 0 x ih 0 x N Co CD 1 I m z 0 z z C, 0 -a 0 -a m I m 0 0 0 0 -1 CD C 0 0 CD 6 0 Co 0 0 01 0 WORLD Vacation Handy Disney World Kennedy Space Center rest Florida 3 Bedrooms sleeps 8 Kitchen A/C Pool Tennis lots B/C flying Nov-May $500 wk / Jane-Oct 0480 wk / nightly & nssnthly rates also available 617 528-4043 P AW DIESELS Englands Finest 049 35 RIC STD Sud $100 list Eric Clutton 913 Cedar Lane Tullahoma Tenn 37388
Edition: Model Aviation - 1986/12
Page Numbers: 65, 163, 164, 165
Objectives Criteria Success Test Specimen Test Setup Test Loads Test Procedure Instrumentation Data Requirements Objectives always hard define may start wanting something generic like safety much safety want want structure wont fail under reasonable loads whats reason able Make easy yourself specific Let first objective example perform static loading test wing structure will simulate symmetri cal wing bending caused maximum positive high angle attack maximum velocity Thats real flight condition can analyze basis design mission develop acceptable test loads test Let give example might designing Formula Pylon Racer go few races estimate maximum airspeed 150 mph turning radius 100 ft go home positive high angle attack maximum velocity test conditions mind Now sit down design test turn need know couple equations Centrifugal Force gr w weight pounds v velocity feet per second g leration gravity feet per second per second r ing radius feet 1467conversion factor mph feet per second Putting letters side side means multiplied diagonal line means divided notationvv means velocity multiplied itself squared can also written v2 Lift 1189vvS 4hqFLOW cL oil section lift coeffi cient apure number Swing ar square feet 001 189vv known dynamic pres sure q used calculate kinds aerodynamic forces case q 001189x150x1467x150x1467 576 lb/sq ft six-pound model moving 150 mph turning 100-ft radius will need F wvv/gr 150 x 1467 x 150 x 1467/322 x 100 ounds lift wing works out 1 5-G turn 90/6 ctually would need about 15% lift 1035 lb account down tail force making turn possible Based wing area 450/144 3125 ft works outto aliftof1035/3125 331 lb/sq ft get lift will need lift coefficientofcL 1035/576x3125 0575 airfoil data tells num ber reasonable could go high 14 An airplane high angle attack making lot drag slowing down plane might 150 mph straights has slow down turns Slowing down reduces dynamic pressure turn reduces lift have increase cL increasing angle attack numbers can increase cby factor three estimate turning radius may about right same data can estimate lift likely get 150 mph 14/575 x 1035 lb 806 lb/sq ft include wing area inside fuselage lifting area Look F-14 picture make own de cisions would include Continued page 163 I4 L1HJ2 cC 2W- 60/GO z 2180 60Mf1 cjLIS T 2180 /50 p4 Left generalized airfoil properties chart applicable model airplanes lot drag made high angle attack specific information see Theory Wing SectionsIncluding Summary Airfoil Data Dover Publications available Zenith Aviation Books Right Shown visualization addition gust vector affects local airflow model plane flight December 1986 65 photo F-i 4 6-G turn sucking moisture out air humid day taken TV screen Pratt & Whitney 60th Birthday Party High suction developed above airplane right plane view has reduced local air pressure thatof much higheraltitude clouds form picture shows way lifting pressures distributed over span aircraft Note halfelliptical shape near wing tips well contributions forward fuselage large area between engines / 3 AaiqIe AttOCk Realize Genuine Improvement RC Flying Geometron Transmitter Support Completely frees hands control sticks u Extremely comfortable use wear Put levers nothing way Allows concentrate ontake oft instant hat No belts flying because dont have hold transmitter whilebuckles straps no cord around neck operating controls Provides full four corner stickWearing support transmitter stays place mobilityyou carry plane Improves accuracy stick movement because Doubles ideal ground support offers perfect transmitter held stable accessibility keeps transmitter off ground Adjusts two-stick Tx modifications adapt- Ruggedly built heat treated aluminum finished able single stick Tx easy change support plate heavy duty anodize Assembled stainless Simple adjustments ann length shoulder size steel fasteners Deaigned constructed extended Transmitter secured safety catch can removed use 695O aced second yet cannot accidentally fall out PURCHASE ALL THREE ITEMS $995Q dealer order direct GEOMETRON CO INC 12 INGLESIDE ROAD LEXINGTON MA 02173 617 861-6526 SAVE $99Q PROVEN TO BE TREMENDOUS HELP FOR BOTH BEGINNERS AND EXPERTS! Plas $150 shipping COD 250 add5oshi cash stones order nero chatoes aoolo off Ia cononenha US Mass residena add 5% LCD TIMER/STOPWATCH Counts up down preset hold additive features Time out sounds alarm auto shut off Easy read outdoors lithium battery- 21 95* PROTECTIVE BAG Made spece age aluminum coated nylon Reflects suns heat protects Tx dirt dust special fast acting closure ONCE YOU USE IT YOU WILL NEVER FLY WITHOUT IT RC Pylon Racing/Hager Continued page 159 contest Sure weather will clear hope Well Mother Nature did cooperate cause rainy days field hadnt mowed grass reported Paul Zaleskas after extra trip field previous day least four inches long So after panic call Fay Harris quick mow job field good shape contest Thanks Fay time got field clouds disappeared just got course laid out some equipment place Fay came mowed grass good short Fifteen fliers hand start racing fourth heat first round yours truly mid-aired Jeff Faleo unfastened Jeffs right wing making somewhat difficult Jeff complete heat Sorry about No 1 though quite windy caused some real thrills everyone seemed have good time After dust settled engines ceased roaring ended follows 1 Bob Bently 2 Bob Loehner 3 Dan Kane 4 Dave Smith 5 Danny Kane Jr thanks club members nonmembers helped make contest success Thats month See races Bill Hager 706 Glen Haven Dr Conroe TX 77385 Structural Tests/Myers Continued page 65 Now does make sense design test around the 1035-lb figure should go 252 lb can limit maximum maneuvering lift limiting ele vator travel know Formula fliers Should go abrupt pullout terminal-velocity dive can estimate whole-body drag coefficient airplane knowing airplanes weight set weight equal drag find terminal velocity could 180 mph could produce maximum lift 363 lb figure out Down tail force point would about 55 lb de pending tail area tail moment arm airfoil etc Ask yourself Will air plane ever yanked about like will pilot smart enough ease out dive lower G Before answer let give another example Recently took over students 35-powered Cessna foamie up rather high engine quit put nose down gentle dive 200 300 nose down After plane traveled about 50 yd straight line saw wing tips yank up lots dihedral followed violent nose-up pitch airplane As speed built up adding down elevator keep path straight line Since wings held rubberbands seems likely wing lifted off fuselage precipitate pitch-up can see terminal velocity model both control- con figuration-dependent Now lets return question pilot continued feed more down elevator airplane would have pulled itself out dive much lower airspeed rubberbands NEW IMPROVED *flsr WUWIt Medd vim nuere weeli Pew. * WANDIT * USpoweNoDes * *Dealers moOed ______________________ * --- 5 * ImE1 *one eor warrarirhlCORD * *WetorDry *Stick Abrasives * * A Keen Machine gives esceptional 5 * sanding control eacellent tinish * *5955hasic mCi i hal Wand 1 each5 *vihgots5 *~555ffoilder Special vol 2 fiat 1 hair ivund wand 5 Oh 6 gvlS *1 29Deicce mncades 31101 2 hail roond5 *woods 1 hoff wands 10 itional Wands Abrasives available5 S * WANDIT MANUFACTURING 214 288-5789 * *PO Box 266 uite Texas 751495 stronger might have held dive higher velocity case some thing else would have happened possibly horizontal tail would have broken off bending downward Id inclined trust pilot par ticularly competent flight-test program planned future test pilot could carefully work up terminal velocity dive still concern about gusts plane might cross wake another racer traveling 150 mph could introduce sharp-edged vertical gust Tra ditionally gust velocity 40% forward velocity 04 x 150 ph would assuumed case would result instantaneous local velocity vector sum velocities 162 mph increase of2l80 angle attack airplane flying near 00 150 mph gust would increase angle attack beyond stall angle Therefore would expect see maxi mum lift due gusts 150 mph tells us should test 252-lb wing lift 38-lb down tail load Design loads problem see competent test engineer will look SiCil P5RPORM*5CR 0050 iou5tltieff CLlOEtt5 PROS REOEROCE Cash TWO ROLL SIZE Ponneess yOUR ceolcel iccosneanfo RoBRiCAnIOs *55 rLvisc ssneucTIOsS torn *OOivIOsOL POnOERnS $l 20 EOCS OR SIC PACE RiCE SO F7 5 RoouprBC54 Sirro December 1986 163 IMerry ChristmasI FABTRONICSI Make specially good flier whether flies 2 cycle 4 cycle CDI system will give better idle positive spark right time much less residue plane car boat etc plus fact makes cost fuel much less factor run engine pennies stead dollars Nearly engine can converted unit comes pre drilled disk sensor clamp mounting sensor engine 90 day warranty complete instructions con version timing procedure Unit operates 48 volt low current drain weight isa mere 2 oz size 2 x 2 x 75 inches Complete system comes ignition coil spark plug on/off switch igni tion cable also available seperately Bat teries included Please state engine size use ordering Installation very easy no special tools needed Automatic spark advance now available 4 cycle engines Complete System $6995 Cash MO certified check plus $300 P & H Personal checks take time clear Illinois residents please add tax Brochure $100 ndable purchase FABTRONICS 3751111 Rival Hi GaluSImuru III IlUl situation viewpoint worst possible combination events likely happen service attempt test thatcarefully Now Criteria Success What expect wing structure allowed crack long doesnt separate two pieces might concealed damage allowed crush dihedral increases easy change see measure Have designed something structure will yield breaking thus reveal overload Lee Renaud put -in-dia steel dowel wing root Aquila worked beautifully show overloads failing Total failure easy recognize Success may subtle test setup can simple have typical balsa-sheeted foam-core Pattern wing might able set up two sawhorses put pillows avoid crushing structure locally pile loads center section until satisfied other hand have Old-Timer wing lots skinny spars ribs may want spread load around bit carefully Again look F-14 picture idea distribute lift loads test loads themselves always pre sent problem After have designed airplane meet specific set conditions can sure have designed meet critical conditions will actually encounter service Simple swer cant have designed built flown crashed lot airplanes begin understand what works what doesnt keep records next design will always easier will constantly starting over designs will generally overweight well remember Sun-Fli 4-20 large maple block wing panel landing gear block sup ported edges several soft 1/16 balsa ribs tiny plywood doublers end wing sheeting around block blocks tore out time didnt wheels swung back punched through lower surface wing operating turf Du Bro wheels plans building instructions didnt say anything about installation might have satisfac tory flying off pavement flying off turf thinner wheels difficult find out what structure has designed what will withstand unless test Crash loads expect shed few parts crash Ideally primary struc ture should protect radio system engine much possible Thats good RC designs have lot plywood around radio compartment see Bob Aberle design US Navy says cockpit must protect pilot crash exerts 40-G forward 20-G downloads Should want test criteria could push down forward up back both items want test largest load would need would about 447 x 6 lb lb extension mount chainsaw engine Mounts 40 60size engines should resist about 50 lb radio tray four servos switch harness receiver battery must resist about 35 lb Servo rails must resist about 5 lb per servo Handling transportation cludes causes hangar rash Very little attention paid loads until plan pack ship aircraft Well come back later George M Myers 70 Froehlich Farm Rd Hicksville NY 11801 CL Aerobatics/Fancher Continued page 66 present extend token appreciation gratitude wish add printed thanks love Rev Id also like acknowledge help several people owe personal thanks Lou Dudka Glen Meador whipping up beautiful foam wing short notice two years ago found time complete spring Large James Greenaway man expertise greatly admire notwithstanding fact dont agree everything supplying modified hemi-head used good advantage ST 46 smoother economical stock squish-band head slight loss power especially good friends Gary McClellan Don McClave both qualified finals themselves gave unselfishiy expertise support became clear would competing top prize Thanks Last certainly least Thank kind enough call write congratulations thoughtfulness greatly appreciated thought might interesting relate TME DIFFERENT FOAM MODEL ILowest Cost Med sing Send $100 latest fine-grain sheet foam I developments foam samples FREE foam 3 sources Hard Shell finishes now LIable Dozens easy build foam air plane plans Peanuts RIC FOAM SCALE MODELS SS2MA St Croix Falls WI 84024 164Model Aviation IMPORTED DIESELS A-UAurorsD-CEDMVVSMUtsEnyS PAWTspIln Standard R/C.0864S Acre & Marine VlntageSpert eat Send *100 InformatIon CARLSON ENGINE IMPORTS 814 East Marconi Phoeiilx AZ 85022 WORLOS BIOGES SCALE PHOTO SERVICE 500 PHOTO RECKS PLANS EWS PHOTO-PACKSPLANS CNLARGING CASE E-ISglng CO Catalog S3O0 SCALE PLANS PHOTO SERVICE 3209 Mednon Gepsboo NC 27403 Phone 19152925239 No COIIOCI couple factors proved instrumental victory year First selected tactical approach achieving goal second learned valuable lesson about making engines work As reported two months ago experiment Enya four-stroke proved fruitless left brand new alrplane very good flier weighed 59 ozon ragged edge too heavy basically-stock ST 46s alrplane capable flying some precise maneuvers long wasnt pressed too hard After couple practice sessions Don Gary decided alrplane could consistently fly fairly high-scoring maneuvers 32- 35-point rangebut pushed fly really hard corners super-small maneuvers search another point two would inevit ably cause blow couple maneuvers badly Unfortunately has experience couple poor maneuvers pattern will adversely affect scores others well could really nail couple maneuvers overall score would suffer result obviously poor ones night before qualifying decided plan action would fly conservatively try give judges obvious reasons socking would fly no smaller no tighter no faster confident flying well 99% time Although flew few wowwww maneuvers during entire week also flew awwwwful maneu ver results speak themselves moral story take stock assets debits going competition devise game plan based evaluation Size up competition equipment physical condition weather Set real istic goal local champ goal quite honestly will likely embar rass yourself should probably fly con servatively avoid opening doors upand-coming hotshots fly through other hand up and-comers have very little lose letting hang out within honest limits your equipments ability Avoid trying change style accommodate some perceived pre ference part judges perception correct chance successfully changing style couple flights ranges slim Continue good job showing judge what doesnt like return fly another daywith luck itll front discerning judge Engines Over last 10 years have become pretty well-known inconsistent en gine runs ST 46s year ran like clocks week long Did find secret ask Well think found Give try major problem has always getting engine would run same speed entire tankflight after flight after flight Also needle valves incredibly sensitivethe tiniest adjustment making large changes always expected direction would get occasional good run among variety too slow too fast ones until after anywhere maybe 50 flights engine would simply break two-cycle couple laps after takeoff stay flew entire 1984 Walker Flyoff Reno dead two-cycle very reason Shortly before years Nats began have problem again started usual fix rearranging praying Upon disassembly however noticed dlscoloration several places side piston below ring color matched blue hue fuel using classic indlcation blowby condition seal between ring cylinder wall broken explosive charge escapes combustion chamber thereby re ducing cylinder pressure output torque engine temporarily reassembled piston cylinder sleeve noticed areas discoloration occurred piston corre sponded areas cylinder walls polished appearance two pieces evidence got old think tank cranked up conclusions fix knock wood has proved 100% successful point What feel happening could likened hydroplaning phenomenon occurs tire running surface covered water some point depending velocity tire pressure layer water builds up between tire road surface contact tween two lost resulting loss ability control direction tire inability stop vehicle tire mounted Hydroplaning significant problem instance attempting stop heavy air liner wet runway Obviously slick tire much suscepti ble hydroplaning tread ever hydroplaning can problem treaded tires too solution has employed full-scale aviation has cut grooves surface runways combination treaded tires grooved runway effectively eliminates hydroplaning allowing com pressed water place dissipate theory piston ring will effect hydroplane layer oil over highlypolished areas cylinder wall destroying seal consequently reducing cylinder pressure necessary consistent fourcycle operation two-cycle engine results erratic super-sensitive-to-the-needle speed-stunt Tigres fix consists purchasing inexpensive brake cylinder hone automotive parts store chucking up cheapie drill press running slowest possible speed hone cylinder walls until uniformly dull appearance approximate crosshatch pat tern tiny scratches made cylinder hone act like grooves runway allowing oil December 1986 165 ziJ f7 N 0 Co 0 x ih 0 x N Co CD 1 I m z 0 z z C, 0 -a 0 -a m I m 0 0 0 0 -1 CD C 0 0 CD 6 0 Co 0 0 01 0 WORLD Vacation Handy Disney World Kennedy Space Center rest Florida 3 Bedrooms sleeps 8 Kitchen A/C Pool Tennis lots B/C flying Nov-May $500 wk / Jane-Oct 0480 wk / nightly & nssnthly rates also available 617 528-4043 P AW DIESELS Englands Finest 049 35 RIC STD Sud $100 list Eric Clutton 913 Cedar Lane Tullahoma Tenn 37388