FF Power Model Trim Part I

Power Model 7171RIIVL iPirt U Bob Johannes problem trimming adjusting powered Free Flight models has us since first Brown engine fired up hauled model skyward problem reach best compromise between diverse flight conditions relatively high-speed flight during engine run slow floating glide As engines became powerful model designs evolved trim techniques change trim philosophy discussed has assimilated through several years personal experimentation combined advice WIND expert modelers think modern concept Free Flight trimming fortunately applies older Free Flight designs well have successfully used philosophy Ohlsson 60-powered New Ruler Ohisson 23-powered Brooklyn Dodger K&B Greenhead powered Ramrods several modern high-powered AMA Gas Free Flight models Trimming starts before ever get flying field cant put enough emphasis importance proper GLIDE PATH TRANSITION PT POWER PATH LAUNCH PT RE 1 setup start Consider objectives flight can divided three distinct-but-related segments climb power pattern transition glide glide pattern model must have stable consistent relatively steep climb steepness climb will vary power-to-weight ratio model Modern AMA Gas models Schnuerle ported engines can climb straight up accelerate several seconds model must transition smoothly high-speed climb slow floating glide no dips stallsno loss altitude glide pattern must circular turn small enough model can force its way thermals open possible good glide efficiency Achieving optimum flight requires compromises three segments must addressed simultaneously best overall flight although Variable Incidence Tailplane [VIT]/auto rudderequipped models allow high degree separation among flight segments What does good flight look like models bunt drop horizontal stabilizer down transition raise again glide power pattern should look like model flying up inside cylinder model should turning right rolling left lift wing always pointed toward centerline cylinder cylinder will leaning downwind engine cutoff model should appear slide right roll left transitions steep bank angle associated climb wings-level glide attitude apparent slipping slide right also lowers 76 Model Aviation Screw adjustment incidence VIT models Left screw power right glide Note depth difference Center Simple homemade declinometer makes decalage measurement easy important first-flight setup Bottom Nylon screw used adjust incidence stab trailing edge fixedsurface models nose fuselage glide attitude Figure 1 illustrates flight pattern transition flows smoothly slow aesthetically pleasing floating glide Free Flight models renowned discussion will tell achieve such flight applying trim philosophy use basis philosophy 1 rightright pattern model turns right under power right glide 2 use decalage incidence difference between wing tail rudder tab primary adjustments power pattern 3 use Center Gravity CG location turn radius glide trim Before can get detailed discussion trimming need establish some definitions can effectively communicate about specific trim adjustments directions mentionedright left up downrefer motions would see seated cockpit airplane axes about model rotates flight pitch axis roll axis yaw axis definition differs previously developed models however feel descriptive motions want induce consistent technical tenninology used full-scale aircraft pitch axis axis about model rotates raise lower nose Trim inputs have principal effect axis come horizontal tail stabilizer Stab-trailing-edge up upelevator will cause nose raise vice versa roll axis axis about model rotates raise lower wing models rotations about axis principally controlled wing twist March 1997 77 example wing twist leading-edgeup right wing will cause model roll left right wing would said have washin An easy way remember difference between washin washout washin increases incidence incidence angle flying surface [wing taill meets airflow normal flight yaw axis axis about model rotates swing nose right left principle trim yaw axis rudder example trailing-edgeright right rudder will cause nose swing right Notice axis discussed identified principal control affects axis Unfortunately its quite simple axes coupled Coupling results trim adjustments made axis causing related motions other axes An example coupling would right-rudder input swings nose right causes left wing move faster right wing speed difference causes left wing generate lift thereby roll model right creating bank angle Since wing lift no longer pointing straight up because bank angle nose goes down model speeds up generating lift until vertical component lift again equals weight model model equilibrium no tendency accelerate along axis Although coupling may sound complicated fairly straightforward fact coupling thing makes model trim adjustments produce desired effect Two definitions will also needed following discussion Fixed-surface models use no trim changes during flight VIT models typically will change stab incidence rudder position during transition power glide trim changes controlled multifunction mechanical timer photo shows example ability make trim changes can implemented Successful Free Flight models have certain common characteristics enhance ease trimming model must built accurately Since article intended address design process models assumed model proven design has built kit plans Accurate building means plans followed precisely possible wing must straight true adequate torsional rigidity will twist flight air loads faster model flies under power twist-proof wing must Old-Timer Nostalgia models covering must provide torsional stiffness bare structure usually rather flimsy torsion rules preclude structural modifications AMA Gas models wings can built very stiff using full-chord diagonal ribs Assuming model has conventional polyhedral wing design let describe properly built wing tip dihedral angles equal dihedral joints tip panels center parallel line flight panels flat except right main panel has degree washin tip polyhedral break should built structure uses diagonal ribs older designs must warped using covering hold twist Right now can hear saying Wait minuteyou said build according plan plans dont say anything about washin main panel Let explain change appropriate Any model intended turn right under power must have washin right wing cause left roll want keep model spiraling ground natural right turn typical pylon models under power Im sure twist often deleted plans maybe designer thought trim adjustment rather construction element plans may call washout tip panels Washout reduces drag important wing designs have tapered tip panels use washout tips use precaution assure twist equal both tips unless design specifically calls differential washout fixed-surface models recommend differential mentioned earlier older models require twist warped after wing covered using heat-shrink plastic covering no problem what using doped tissue silk covering same techniqueusing heat gun would use plastic coveringsalso works very well doped coverings Dried dope thermoplastic materialat normal temperatures firm holds its shape However heated softens can reshaped cools holds new shape Tissue silk excellent covering materials because add great amount stiffness structure fact wing double-covered tissue will stiff proverbial board heat gun sealing iron can also used permanently get rid wrinkles unwanted warps Dont forget use pin punch vent hole bay covering wing must balanced laterally Hold inverted thumb finger center dihedral break add lead light tip until wing balances important because model will want turn toward heavy tip could interfere desired trim adjustments usually balance wing before covering lead weight concealed inside other components must also built accurately fuselage must straight Unless have flat building board difficult build straight fuselage slight bow up down easier accommodate side-to-side bow usually build fuselage socalled slab type top bottom can assure correct lateral alignment draw centerline down top aid pylon fin alignment During trial-fitting can use line level side pylon fin verify important alignment horizontal tail stabilizer must flatno twist Stabs seem want bow 78 Model Aviation w stop rudder tab provides easy means accurately set important adjustment Spring provides tension hold tab desired position LDM Industries Model Accessories Universal Servo Tray measures 23 42 inches designed hold over 50 different standard mid-size servos 2 le tray features adjustable mounting brackets molded tough glass filled nylon durability Part #6000 . Universal Servo Tray .. $495 Con-Do-It Con-Do-It clear PVC tubing 1/2 outside diameter 023 wall thickness Con-Do-It provides neat simple way running servo lead extensions fuel lines air lines wiring harnesses through model package contains two 24 pieces Con-Do-It Part #7500Con-Do-It$495 Model Chocks lock place models axles prevent model rolling around car during transport flying field packaged sets two designed fit 5/32 axles up 3 diameter wheels Part #7000Model Chocks$395 order send check money order including $400 S&H LDM Industries Inc PO Box 292396 Tampa FL 33687-2396 Phone 813 991-4277 Fax 813 991-4810 Florida residents add 6% sales tax VISA MASTER CARD Accepted 1996 LDM Industries Inc JOHN POND - Old Time Plan Service largest selection plans world reasonable prices CATALOGS TIMER/FREE FUGHT NOSTALGIA RUBBER POWERCONTROI UNE/1AOlO CONTROL $500 * FLYING S$500Minimum Order $1000 VISA ACCEPTED ROBox9O3lO MA ZISan Jose CA 95109-3310 Phone 408 292-3382 Tue. upward tips covered little bow OK must eliminate twist may appear during construction covering Again heat gun will take out unwanted twist next step properly set up model setup consists properly aligning wing tail fuselage correctly locating center balance commonly called CG setting up proper wing/tail decalage checking engine-thrust offsets align wing fuselage stick pin top fin some other convenient location rear fuselage centerline Take length light Control Line cable something else wont stretchdont use thread loop end Mount wing pylon Put cable loop over pin measure some convenient point such polyhedral joint trailing edge wing measure corresponding point other wing Align wing until distances equal key wing always same alignment fuselage thereby avoiding trim variations flight flight Keying often accomplished gluing small pieces split dowel surfaces adjacent point contact fuselage necessary use keys tail unless fin built tail Nostalgia Old Timer models Keying older designs essential assure consistent alignment fin model fixed-surface rather VIT will need provide stab tilt glide turn Stab tilt efficient effective way adjust glide turnit has little effect power pattern good place start tilt stab until aligns inboard panel right wing tilt tighter turn VIT models keep stab level provide glide turn auto rudder glide turn Old-Timer models like use free-floating drag flap right wing trailing edge flaps will streamline model PAT 4221432 Rem ata 1-SOFT MOUNTED ENGINESJLVE IT WIll-I WRECKING GLOW DRIVER 2-HARD TO GET AT PLUGHEAD 3LARGE/DEEP COWLINGI 4FINGERS CLOSE TO PROP FITS ALL STANDARD PLUG5SCALE PROJECr NO HOLER EM OT E FROM K&B 2 STROKE TOHEAOLOKFOR GLOW DRIVER ENTA 4 STROKE ST#021 SINGLE$995 ST#022 TWIN$1395 IF tvr AVAflAEZD 1m $100 $200ps 80 Model Aviation 77 Universal Servo Tray Model Chocks GOT PROBLEM MODEL PRODUCTS CORPRD BOX 100 ALLAMUCHY NJ 07820908 850-1508 moving fast under power will droop down glide causing right turn tighten turn add weight flap open turn reduce size flap flap Class B Brooklyn Dodger l/2 x 1 Class C New Ruler its 2 x 3 Now surfaces properly aligned keyed can check balance decalage balance model use some type support fairly sharp contacts model Trying balance model fingertips just accurate enough use two pieces molding material tack brads end workbench contact surfaces tapered rounded Yis fixed-surface models will likely vary CG adjust glide important know start Put CG shown plans adding weight nose tail necessary Nostalgia modern AMA models CU will normally 7585% wing chord behind leading edge Old Timer models 50-55% appropriate VIT models usually use CU 55-65% range Next comes decalage fixedsurface models typical wing have 11/220 incidence stab Very few plans give information tend rely parts patterns linear dimensions pylon provide required angular difference approaches adequate because small variations may creep during construction VIT models two decalage settings Power trim usually around 1 glide trim near 20 measure decalage use simple inclinometer made circular protractor Glue protractor piece plywood straight edge bottom Drill small hole center protractor insert piece Teflon tubing cyanoacrylate CyA glue bottle Place inclinometer bottom wing tail get angular difference reading true measure incidence since five minutes can upgrade stan dard Futaba Airtronics servos ball bearing servos new EMS Ball Bearing Conversion Kit New casetops accurately molded supertough glass filled fuel-proof Celcon include top quality stainless steel ball bearing servo output shaft * Stops case top andlor plastic bushing wear * Prevents output gear shaft shimmy * Reduces friction improves servo centering * Enhances performance airplanes boats & cars * Mandatory helicopter servos * Free output arm provided case top * Guaranteed against breakage year * Why pay $3995 $2995 BBC-1 Fits FUTABA 528/5128 S38/S 138 S48/S 148 Servos set 4$2595 BBC-2As above set 1$695 BBC-3Fits AIRTRONICS 94102 Servos set 4$2595 BBC-4As above set I$695 BBC-5Ball Bearing Only JR 501 507 RCDAPOLLO 05 10 FOCUS HS300 HS500 ACE 330342 342HS TOWER TS-5t Servos set 4$1995 Add $300 Shipping Handling orders 14 692-1393 Info OnlyCalifornia Residents Add 775% Sales Tax 800 845-8978 Orders Only* VISA MASTERCARD Accepted Spak LlgnItlon ~StemI SYNCRO SPARK MICROPROCESSOR ELECTRONIC TIMING CONTROL EASY TO INSTALL PLUGS BETWEEN YOUR PULSE SWITCH AND IGN SYSTEM OVING PARTS TO WEAR OUT OR GET OUT OF ADJUSTMENT SPARK TIMING WITH EACH ENGINE REvOLUTION COMPLETELY STABLE TIMING IS ROCK SOLID AND DOES NOT JUMP AROUND RETRO FIT TO MOST ALL BRANDS OF ADD-ON IGNITION SYSTEMS WITH HALL EFFECT TRIGGER WILL NOT WORK WITH REICHMUTI-I OR PRO SPARK SYSTEMS WE HAVE ALL PARTS TO CONVERT YOUR 28 & 32CC MCCULLOCH WEED TRIMMER ENGINES TO AIRPLANE USE WITH CDI IGNITION WE NOW HAVE THE JUMP START SYSTEM FOR THE ZENOAH G 45 & 62cc AND Z445 TWIN AND THE U S ENGINES 35 & 41cc WE HAVE THE RIM FIRE 1/4 x 32 SPARK PLUGS IN STOCK $1295 PLUS SHIPPING AND HANDLING BULLY 12 LSI2 UAV has defied designers designed new head new port layout produce 12 LS/2 engine runs smooth silk fantastic verticals flawless transition easy throttle control using APC 16x14 Propeller two stroke low maintenance high performance engine enhanced pump regulator Compare engine engines now used pattern competition BULLY will out perform others smoothness pulling power reliability $ 39800$ 29800 UUAV Inc PO Box 1548 Bend OR 97709 Fax 541-385-0117 Call 800-294-9506 BULLY 12 PRI2 Bully 12 P1112 next generation full race engine enhanced porting modified head pump produce engine will set standard sport race flying Bully 12 P1112 natural evolution 12 PR no way replaces makes race engine user friendly two stroke low maintenance high performance engine will satisfy lust power stock full line accessories four muffler types designed engine rugged four point soft mount March 1997 83 IUILIO LII lUd *d $3995 PLUS SHIPPING & HANDUNG MArs MORE CESSORIES PARTS CUSTOM INSTALLATION SEND $2 FOR PRICE UST NEWSLETTER ORDERING INSTRUCTIONSI ElevonMixer ELECTRONIC MIXER elevons v-fails flaps SpOilers Ultra-simple setup installation Rugged microprocessorbased design 100% electronic high reli ability Simply convecto between servos avd receiver Pastures servo reversing aed tour different wiving rates allow tailor miser needs model Will overdrive servos options selected simple dip switch Made USA designed work simple ineupes sloe AM PM radio systems Very low power vunsumption Size 16 nO9 504 Weight O250z Less radio cosneotors Part No OA $3095 less cessectors $4096 complete $ct~ EngineSynchronizer System ENGINE SYNCHRONIZER SYS0 molfi-engine aircrah beeps engises running seine idle through full power sys few cossists MasterUod SlaveUnits MasterUn responds throsle slick ars reads RPM use engine communds SlaveUnit other engines Microprocesvur-bused design features reversible servo u.,., ,,ttIe-back sync release un engise sot Can sync 2 6 engines 100% electronic Made USA designed work popular radio systems Very small size 17 5 11 u 04 Weight 05oz Low power coo sumption Less radio cossectocs Part No gM MasterUolt $3995 694199 StaveUnIt $3996 Complete systems other productsPO Boo 3129 COSPIIS CHetni available planes cars boatsOsoses & t5FO t612 914-994311 ca5or write detailsCusnoiros Snevics FAX & AFTEr GlowDriver interested difference works great adjust decalage can use thin plywood metal shims under leading edge trailing edge stab appropriate until get desired measurement However highpowered AMA models prefer use nylon screw stab incidence adjustment screw threaded plywood set fuselage stab trailing edge rests head screw held against tension dethermalizer DT line nylon screw allows easy adjustment provides ability change decalage predetermined amount during course contest Ill explain value capability get flying screw adjustment rudder tab useful same reasons Start flying rudder tab centered last element setup check engine thrust offsets usually start thrustline straight aheadno upthrust downthrust no side thrust past thrust offsets sometimes quite large common trim adjustment However engines have become powerful causing models accelerate quickly thrust offsets effective initial phase power patternbefore aerodynamics model take over speed builds up will probably end up little left thrust model trimmed Ill talk about appropriate point during flying discussion may saying yourself supposed discussion trim model have hardly talked about flying yet Youre right However successful trimming starts lay down first piece balsa build model have followed procedure point can fairly confident airplane will crash during first flights now ready take model flying field lets go flying Part II Trim Philosophy will featured May 1997 issue 4I ULTIMATESPORT RC 255 East Ashland/PO Boo 727/Suds Springs dubs 63276 5LtI9O1E 5550 lIPS-256S47-37d2F, Frihe 11 Sd SASc 84 Model Aviation TURN now offers very finest versatile lightweight PROP HUBS turned solid barstock inside out true running hub new hub will mount motor standard TRU-TURN adapter kit big bird multi-bolt applications TRU-TURN has covered TRU-TURN also has PROP NUT will fit motor precision PROP NUTS come engine thread sizes two different shapes available stock Ask hobby dealer name $JV TM RMO U S PRECISION MODEL PRODUCTS Romco Manufacturing Inc QUALITY VERSATILITY GREAT LOOKS SAFETY PO Box 836 South Houston Texas 77587 713 / 943-1867 MUD DUCK AVIAL ION 7118 Waitmoreland Dr VVA 22186 1134 IntlninsWeiuvrGInesFuseuCo,I Foon Ftvmnstvi-tsvee AInnLendnsOeo CI55rCanopyAeiIsbIe 5jIde, Sir 5255"Sheered Sir 5365Onhi Sheeled ir 5495

Power Model 7171RIIVL iPirt U Bob Johannes problem trimming adjusting powered Free Flight models has us since first Brown engine fired up hauled model skyward problem reach best compromise between diverse flight conditions relatively high-speed flight during engine run slow floating glide As engines became powerful model designs evolved trim techniques change trim philosophy discussed has assimilated through several years personal experimentation combined advice WIND expert modelers think modern concept Free Flight trimming fortunately applies older Free Flight designs well have successfully used philosophy Ohlsson 60-powered New Ruler Ohisson 23-powered Brooklyn Dodger K&B Greenhead powered Ramrods several modern high-powered AMA Gas Free Flight models Trimming starts before ever get flying field cant put enough emphasis importance proper GLIDE PATH TRANSITION PT POWER PATH LAUNCH PT RE 1 setup start Consider objectives flight can divided three distinct-but-related segments climb power pattern transition glide glide pattern model must have stable consistent relatively steep climb steepness climb will vary power-to-weight ratio model Modern AMA Gas models Schnuerle ported engines can climb straight up accelerate several seconds model must transition smoothly high-speed climb slow floating glide no dips stallsno loss altitude glide pattern must circular turn small enough model can force its way thermals open possible good glide efficiency Achieving optimum flight requires compromises three segments must addressed simultaneously best overall flight although Variable Incidence Tailplane [VIT]/auto rudderequipped models allow high degree separation among flight segments What does good flight look like models bunt drop horizontal stabilizer down transition raise again glide power pattern should look like model flying up inside cylinder model should turning right rolling left lift wing always pointed toward centerline cylinder cylinder will leaning downwind engine cutoff model should appear slide right roll left transitions steep bank angle associated climb wings-level glide attitude apparent slipping slide right also lowers 76 Model Aviation Screw adjustment incidence VIT models Left screw power right glide Note depth difference Center Simple homemade declinometer makes decalage measurement easy important first-flight setup Bottom Nylon screw used adjust incidence stab trailing edge fixedsurface models nose fuselage glide attitude Figure 1 illustrates flight pattern transition flows smoothly slow aesthetically pleasing floating glide Free Flight models renowned discussion will tell achieve such flight applying trim philosophy use basis philosophy 1 rightright pattern model turns right under power right glide 2 use decalage incidence difference between wing tail rudder tab primary adjustments power pattern 3 use Center Gravity CG location turn radius glide trim Before can get detailed discussion trimming need establish some definitions can effectively communicate about specific trim adjustments directions mentionedright left up downrefer motions would see seated cockpit airplane axes about model rotates flight pitch axis roll axis yaw axis definition differs previously developed models however feel descriptive motions want induce consistent technical tenninology used full-scale aircraft pitch axis axis about model rotates raise lower nose Trim inputs have principal effect axis come horizontal tail stabilizer Stab-trailing-edge up upelevator will cause nose raise vice versa roll axis axis about model rotates raise lower wing models rotations about axis principally controlled wing twist March 1997 77 example wing twist leading-edgeup right wing will cause model roll left right wing would said have washin An easy way remember difference between washin washout washin increases incidence incidence angle flying surface [wing taill meets airflow normal flight yaw axis axis about model rotates swing nose right left principle trim yaw axis rudder example trailing-edgeright right rudder will cause nose swing right Notice axis discussed identified principal control affects axis Unfortunately its quite simple axes coupled Coupling results trim adjustments made axis causing related motions other axes An example coupling would right-rudder input swings nose right causes left wing move faster right wing speed difference causes left wing generate lift thereby roll model right creating bank angle Since wing lift no longer pointing straight up because bank angle nose goes down model speeds up generating lift until vertical component lift again equals weight model model equilibrium no tendency accelerate along axis Although coupling may sound complicated fairly straightforward fact coupling thing makes model trim adjustments produce desired effect Two definitions will also needed following discussion Fixed-surface models use no trim changes during flight VIT models typically will change stab incidence rudder position during transition power glide trim changes controlled multifunction mechanical timer photo shows example ability make trim changes can implemented Successful Free Flight models have certain common characteristics enhance ease trimming model must built accurately Since article intended address design process models assumed model proven design has built kit plans Accurate building means plans followed precisely possible wing must straight true adequate torsional rigidity will twist flight air loads faster model flies under power twist-proof wing must Old-Timer Nostalgia models covering must provide torsional stiffness bare structure usually rather flimsy torsion rules preclude structural modifications AMA Gas models wings can built very stiff using full-chord diagonal ribs Assuming model has conventional polyhedral wing design let describe properly built wing tip dihedral angles equal dihedral joints tip panels center parallel line flight panels flat except right main panel has degree washin tip polyhedral break should built structure uses diagonal ribs older designs must warped using covering hold twist Right now can hear saying Wait minuteyou said build according plan plans dont say anything about washin main panel Let explain change appropriate Any model intended turn right under power must have washin right wing cause left roll want keep model spiraling ground natural right turn typical pylon models under power Im sure twist often deleted plans maybe designer thought trim adjustment rather construction element plans may call washout tip panels Washout reduces drag important wing designs have tapered tip panels use washout tips use precaution assure twist equal both tips unless design specifically calls differential washout fixed-surface models recommend differential mentioned earlier older models require twist warped after wing covered using heat-shrink plastic covering no problem what using doped tissue silk covering same techniqueusing heat gun would use plastic coveringsalso works very well doped coverings Dried dope thermoplastic materialat normal temperatures firm holds its shape However heated softens can reshaped cools holds new shape Tissue silk excellent covering materials because add great amount stiffness structure fact wing double-covered tissue will stiff proverbial board heat gun sealing iron can also used permanently get rid wrinkles unwanted warps Dont forget use pin punch vent hole bay covering wing must balanced laterally Hold inverted thumb finger center dihedral break add lead light tip until wing balances important because model will want turn toward heavy tip could interfere desired trim adjustments usually balance wing before covering lead weight concealed inside other components must also built accurately fuselage must straight Unless have flat building board difficult build straight fuselage slight bow up down easier accommodate side-to-side bow usually build fuselage socalled slab type top bottom can assure correct lateral alignment draw centerline down top aid pylon fin alignment During trial-fitting can use line level side pylon fin verify important alignment horizontal tail stabilizer must flatno twist Stabs seem want bow 78 Model Aviation w stop rudder tab provides easy means accurately set important adjustment Spring provides tension hold tab desired position LDM Industries Model Accessories Universal Servo Tray measures 23 42 inches designed hold over 50 different standard mid-size servos 2 le tray features adjustable mounting brackets molded tough glass filled nylon durability Part #6000 . Universal Servo Tray .. $495 Con-Do-It Con-Do-It clear PVC tubing 1/2 outside diameter 023 wall thickness Con-Do-It provides neat simple way running servo lead extensions fuel lines air lines wiring harnesses through model package contains two 24 pieces Con-Do-It Part #7500Con-Do-It$495 Model Chocks lock place models axles prevent model rolling around car during transport flying field packaged sets two designed fit 5/32 axles up 3 diameter wheels Part #7000Model Chocks$395 order send check money order including $400 S&H LDM Industries Inc PO Box 292396 Tampa FL 33687-2396 Phone 813 991-4277 Fax 813 991-4810 Florida residents add 6% sales tax VISA MASTER CARD Accepted 1996 LDM Industries Inc JOHN POND - Old Time Plan Service largest selection plans world reasonable prices CATALOGS TIMER/FREE FUGHT NOSTALGIA RUBBER POWERCONTROI UNE/1AOlO CONTROL $500 * FLYING S$500Minimum Order $1000 VISA ACCEPTED ROBox9O3lO MA ZISan Jose CA 95109-3310 Phone 408 292-3382 Tue. upward tips covered little bow OK must eliminate twist may appear during construction covering Again heat gun will take out unwanted twist next step properly set up model setup consists properly aligning wing tail fuselage correctly locating center balance commonly called CG setting up proper wing/tail decalage checking engine-thrust offsets align wing fuselage stick pin top fin some other convenient location rear fuselage centerline Take length light Control Line cable something else wont stretchdont use thread loop end Mount wing pylon Put cable loop over pin measure some convenient point such polyhedral joint trailing edge wing measure corresponding point other wing Align wing until distances equal key wing always same alignment fuselage thereby avoiding trim variations flight flight Keying often accomplished gluing small pieces split dowel surfaces adjacent point contact fuselage necessary use keys tail unless fin built tail Nostalgia Old Timer models Keying older designs essential assure consistent alignment fin model fixed-surface rather VIT will need provide stab tilt glide turn Stab tilt efficient effective way adjust glide turnit has little effect power pattern good place start tilt stab until aligns inboard panel right wing tilt tighter turn VIT models keep stab level provide glide turn auto rudder glide turn Old-Timer models like use free-floating drag flap right wing trailing edge flaps will streamline model PAT 4221432 Rem ata 1-SOFT MOUNTED ENGINESJLVE IT WIll-I WRECKING GLOW DRIVER 2-HARD TO GET AT PLUGHEAD 3LARGE/DEEP COWLINGI 4FINGERS CLOSE TO PROP FITS ALL STANDARD PLUG5SCALE PROJECr NO HOLER EM OT E FROM K&B 2 STROKE TOHEAOLOKFOR GLOW DRIVER ENTA 4 STROKE ST#021 SINGLE$995 ST#022 TWIN$1395 IF tvr AVAflAEZD 1m $100 $200ps 80 Model Aviation 77 Universal Servo Tray Model Chocks GOT PROBLEM MODEL PRODUCTS CORPRD BOX 100 ALLAMUCHY NJ 07820908 850-1508 moving fast under power will droop down glide causing right turn tighten turn add weight flap open turn reduce size flap flap Class B Brooklyn Dodger l/2 x 1 Class C New Ruler its 2 x 3 Now surfaces properly aligned keyed can check balance decalage balance model use some type support fairly sharp contacts model Trying balance model fingertips just accurate enough use two pieces molding material tack brads end workbench contact surfaces tapered rounded Yis fixed-surface models will likely vary CG adjust glide important know start Put CG shown plans adding weight nose tail necessary Nostalgia modern AMA models CU will normally 7585% wing chord behind leading edge Old Timer models 50-55% appropriate VIT models usually use CU 55-65% range Next comes decalage fixedsurface models typical wing have 11/220 incidence stab Very few plans give information tend rely parts patterns linear dimensions pylon provide required angular difference approaches adequate because small variations may creep during construction VIT models two decalage settings Power trim usually around 1 glide trim near 20 measure decalage use simple inclinometer made circular protractor Glue protractor piece plywood straight edge bottom Drill small hole center protractor insert piece Teflon tubing cyanoacrylate CyA glue bottle Place inclinometer bottom wing tail get angular difference reading true measure incidence since five minutes can upgrade stan dard Futaba Airtronics servos ball bearing servos new EMS Ball Bearing Conversion Kit New casetops accurately molded supertough glass filled fuel-proof Celcon include top quality stainless steel ball bearing servo output shaft * Stops case top andlor plastic bushing wear * Prevents output gear shaft shimmy * Reduces friction improves servo centering * Enhances performance airplanes boats & cars * Mandatory helicopter servos * Free output arm provided case top * Guaranteed against breakage year * Why pay $3995 $2995 BBC-1 Fits FUTABA 528/5128 S38/S 138 S48/S 148 Servos set 4$2595 BBC-2As above set 1$695 BBC-3Fits AIRTRONICS 94102 Servos set 4$2595 BBC-4As above set I$695 BBC-5Ball Bearing Only JR 501 507 RCDAPOLLO 05 10 FOCUS HS300 HS500 ACE 330342 342HS TOWER TS-5t Servos set 4$1995 Add $300 Shipping Handling orders 14 692-1393 Info OnlyCalifornia Residents Add 775% Sales Tax 800 845-8978 Orders Only* VISA MASTERCARD Accepted Spak LlgnItlon ~StemI SYNCRO SPARK MICROPROCESSOR ELECTRONIC TIMING CONTROL EASY TO INSTALL PLUGS BETWEEN YOUR PULSE SWITCH AND IGN SYSTEM OVING PARTS TO WEAR OUT OR GET OUT OF ADJUSTMENT SPARK TIMING WITH EACH ENGINE REvOLUTION COMPLETELY STABLE TIMING IS ROCK SOLID AND DOES NOT JUMP AROUND RETRO FIT TO MOST ALL BRANDS OF ADD-ON IGNITION SYSTEMS WITH HALL EFFECT TRIGGER WILL NOT WORK WITH REICHMUTI-I OR PRO SPARK SYSTEMS WE HAVE ALL PARTS TO CONVERT YOUR 28 & 32CC MCCULLOCH WEED TRIMMER ENGINES TO AIRPLANE USE WITH CDI IGNITION WE NOW HAVE THE JUMP START SYSTEM FOR THE ZENOAH G 45 & 62cc AND Z445 TWIN AND THE U S ENGINES 35 & 41cc WE HAVE THE RIM FIRE 1/4 x 32 SPARK PLUGS IN STOCK $1295 PLUS SHIPPING AND HANDLING BULLY 12 LSI2 UAV has defied designers designed new head new port layout produce 12 LS/2 engine runs smooth silk fantastic verticals flawless transition easy throttle control using APC 16x14 Propeller two stroke low maintenance high performance engine enhanced pump regulator Compare engine engines now used pattern competition BULLY will out perform others smoothness pulling power reliability $ 39800$ 29800 UUAV Inc PO Box 1548 Bend OR 97709 Fax 541-385-0117 Call 800-294-9506 BULLY 12 PRI2 Bully 12 P1112 next generation full race engine enhanced porting modified head pump produce engine will set standard sport race flying Bully 12 P1112 natural evolution 12 PR no way replaces makes race engine user friendly two stroke low maintenance high performance engine will satisfy lust power stock full line accessories four muffler types designed engine rugged four point soft mount March 1997 83 IUILIO LII lUd *d $3995 PLUS SHIPPING & HANDUNG MArs MORE CESSORIES PARTS CUSTOM INSTALLATION SEND $2 FOR PRICE UST NEWSLETTER ORDERING INSTRUCTIONSI ElevonMixer ELECTRONIC MIXER elevons v-fails flaps SpOilers Ultra-simple setup installation Rugged microprocessorbased design 100% electronic high reli ability Simply convecto between servos avd receiver Pastures servo reversing aed tour different wiving rates allow tailor miser needs model Will overdrive servos options selected simple dip switch Made USA designed work simple ineupes sloe AM PM radio systems Very low power vunsumption Size 16 nO9 504 Weight O250z Less radio cosneotors Part No OA $3095 less cessectors $4096 complete $ct~ EngineSynchronizer System ENGINE SYNCHRONIZER SYS0 molfi-engine aircrah beeps engises running seine idle through full power sys few cossists MasterUod SlaveUnits MasterUn responds throsle slick ars reads RPM use engine communds SlaveUnit other engines Microprocesvur-bused design features reversible servo u.,., ,,ttIe-back sync release un engise sot Can sync 2 6 engines 100% electronic Made USA designed work popular radio systems Very small size 17 5 11 u 04 Weight 05oz Low power coo sumption Less radio cossectocs Part No gM MasterUolt $3995 694199 StaveUnIt $3996 Complete systems other productsPO Boo 3129 COSPIIS CHetni available planes cars boatsOsoses & t5FO t612 914-994311 ca5or write detailsCusnoiros Snevics FAX & AFTEr GlowDriver interested difference works great adjust decalage can use thin plywood metal shims under leading edge trailing edge stab appropriate until get desired measurement However highpowered AMA models prefer use nylon screw stab incidence adjustment screw threaded plywood set fuselage stab trailing edge rests head screw held against tension dethermalizer DT line nylon screw allows easy adjustment provides ability change decalage predetermined amount during course contest Ill explain value capability get flying screw adjustment rudder tab useful same reasons Start flying rudder tab centered last element setup check engine thrust offsets usually start thrustline straight aheadno upthrust downthrust no side thrust past thrust offsets sometimes quite large common trim adjustment However engines have become powerful causing models accelerate quickly thrust offsets effective initial phase power patternbefore aerodynamics model take over speed builds up will probably end up little left thrust model trimmed Ill talk about appropriate point during flying discussion may saying yourself supposed discussion trim model have hardly talked about flying yet Youre right However successful trimming starts lay down first piece balsa build model have followed procedure point can fairly confident airplane will crash during first flights now ready take model flying field lets go flying Part II Trim Philosophy will featured May 1997 issue 4I ULTIMATESPORT RC 255 East Ashland/PO Boo 727/Suds Springs dubs 63276 5LtI9O1E 5550 lIPS-256S47-37d2F, Frihe 11 Sd SASc 84 Model Aviation TURN now offers very finest versatile lightweight PROP HUBS turned solid barstock inside out true running hub new hub will mount motor standard TRU-TURN adapter kit big bird multi-bolt applications TRU-TURN has covered TRU-TURN also has PROP NUT will fit motor precision PROP NUTS come engine thread sizes two different shapes available stock Ask hobby dealer name $JV TM RMO U S PRECISION MODEL PRODUCTS Romco Manufacturing Inc QUALITY VERSATILITY GREAT LOOKS SAFETY PO Box 836 South Houston Texas 77587 713 / 943-1867 MUD DUCK AVIAL ION 7118 Waitmoreland Dr VVA 22186 1134 IntlninsWeiuvrGInesFuseuCo,I Foon Ftvmnstvi-tsvee AInnLendnsOeo CI55rCanopyAeiIsbIe 5jIde, Sir 5255"Sheered Sir 5365Onhi Sheeled ir 5495