Radio Control Giant Scale Bob Beckman GUEST COLUMNIST month am going turn space over John Hunton Several years ago before Giant Scale really became popular well-known John working engines RPVs Before us ever run across idea using chainsaw engines models John dai ly basis solving problems involved As result well qualified tell us. Rig Pumping Carburetors Flight John Hunton Industrial-type engines now popular larger model aircraft equipped carburetors designed operate dynamic environment flight notes explain what problems carburetors experience solve Problem No 1 Intake blow-off Most engines interest reed-valve type Note John quite correct statement Just maybe Big Bangers piston-port ed Quadras prime examples However conditions John describ ing can exist both types engine VyL IN2 INTAKE SK1 Carburetors generate wave fuel-en riched blow-back reverse Intake pulses AIR tLoW 5 bb reed close positive pres sure wave generated crankcase side reed Some positive charge flows back up intake out carburetor carburetor intake has open face strong flowof air over carburetor some t e fuel-enriched back-flow will blowin away replaced pure air ext intake pulse resulting leaner mixture see back-flow run engiie night protecting carburetor frothe airstream shine flashlight acro s open carburetor face See sket es No 1 No 2 representa tion f back-flow phenomenon T re some solutions blowoff roblem 1 Build cowling keep rstream off carburetor face solut could lead other problems er atmospheric pressure c rburetor senses changed abou later 2 Install velocity stack~ carburetor face contain l ack-flow next intake pulse see setch No 3the velocity stack can sometimes help engine runs inex plically rough 3 Install properly desiged air cleaner can contain b ck-flow well provide constant press re entrance venturi two very important functions beyond just keepiig gross impurities out intake Probem Na 2 Variations air pressure th venturi flow fuel intake air constant pressure venturi varied changes fuelair ratio will also vary have carburetors mounted face AIP PU-EAIIZ WPACi SK-2 fuel-enriched blow-back blown away replaced pure air thus causing lean condition gFAM2 AT %rnYE ANG1- intake vertical plane tunate setup changes angle pitch airframe during flight will change pressure carburetor face although changes velocity might see sketch No 4 Note respect best arrangement face carburetor parallel line offlight well vertical bb Carburetors mounted otherwise subject strong air pressure variations changes angle attack airframe see sketch No 5 solution both problems 1 2 build air cleaner functions contain back-flow control flow air across carbure tor face Sketch No 6 shows build such device Problem No 3 Variations fuel pres sure typical pumping carburetor amazingly insensitive fuel-level changes fuel tank vent-pressure variations problem design carbu retors however have pres sure-sensing port port provides ambient pressure level diaphragm mechanically compensates fuel flow changes barometric pressures caused altitude changes atmospheric pressure changes air moves across small hole see sketch No 7 changes pressure ingenious device sees Try playing air hose port engine running will observe changes fuel mixture fix problem simple Just provide protective cowling may V LOCJr- STACI cAnE-eTu NGIt SK 3 velocity stack can contain blow back next intake pulse A1-tI2AM AT f126AflV AN6L cF A7TAC 52 Model Aviation C 4 Variations angle attack enginelairframe have little effect pressure carburetor intake AIR ROW u - Al FAME POdTIVE AN&L CF ATTACI M NE6AThlE AN&- 9I ATT4Cr-. SK-5 Variations angle attack englnelairframe have significant effect upon air pressure carburetor intake job because possible pres sure changes within cowl certain fix duct port stable point pressure reference have fixed problems 1 2 building proper air cleaner will within carburetor take ahead venturi ducting can accomplished either internally sketch No 8 externally sketch No px 3 ALUMp IVIO63ALLM STANCAP L FrM EFQE E IV AtUM PLA7 r A5 *5INE SK-6 Air cisaner can contain biowback provide air prossure carb intake 9 depending design engine further note carburetors may interesting improve engine cowling potential ducting intake remote location recom mended because long intake can produce resonances will result uneven engine power output over operating rpm range summary pumping carburetor TAP ANP wrni 5HOT p EW SK-7 First step modifying pressure sensor carburetor INPOUT Ob3 C-HANHL HOLE HO& 00 0 00 K rjtI PLATE PHAM CovZ PLAT& SK8 Further steps modifying pressuresensor carb Read coiumn thorough description O2 7 can provide excellent air-fuel mixtures over wide variety rpm load condi tions proper provisions made environment carburetor operating Thats end Johns discourse Interesting no Coming attractions word starting come event scheduling year First RC Seaplane Fly-in Lakeport CA May 10-11-12 strictly Giant Scale event Giant Scale will probably dominate event will fund-raiser Statue Liberty restoration project Lee Taylor Event Director reports out standing cooperation local authorities site Californias Clearlake beautiful areas have ever seen hotbed both Giant Scale seaplane activity way can vicinity Continued page 152 4-0 o PaV TAP CtvZ L4T2 iwre caNN-r 5U TAPS INITVI QPL~ TLJ 116k Oe~ oC OLT$II kIgASM g PlATE SK9 final steps modifying carbs pressuresensor May 1985 53 / / // 7/ / L LJ 4 THE COMPETITIONS VIEW 'I OF THE WINDSONG I. C, 0 0 N 0 DODGSON DESIGNS 2904 SW CAMANO DRIVE CAMANO ISLAND WA 9825i2J What makes Windsong best plane have deadair lightlift gusting 25 MPH winds thermal contest What makes windsong best plane have x-country race Some say 11to 1 aspect ratio clean solidcore wing no spoiler bays disturb airflow Others say Eppler 214 airfoil combined exclusive full-span camber changing capability including elevator compensated 80 degree flaps reflexible ailerons fact design innovations contribute Windsongs total design concept its unprecedented performance WITH THE WINOSONG THE WHOLE IS TRULY GREATER THAN THE SUM OF ITS PARTS Windsong 19995Camano 15995Pixy 14995 Send 2 stamps catalog VHS video tape too can made readily-avail able materials youll have build some sophisticated electronics make work Please forward questions SASE author Happy Electric Landings Bob Kopski 25 West End Dr Lansdale PA 19446 RC Giant Scale/Beckman Continued page 53 dont miss information con tact Lee Taylor 216 Willow Ave Rose ville CA 95678 phone number 916 783-4190 next have information all-time favorite events STARS Scale Rally Olean NY scheduled July 6 7 year another event limited Giant Scale dont see much else flying site hospitality fantastic place might see Giant Scale aircraft IMAA Fun-Fly Festival IMAA bash year set July 18-21 Mobile AL fifth year event note time change August July Like Nats FFF rotating around different loca tions year like idea since gives IMAA members around country chance participate what Im hearing will another great Im putting weight just reading menus picnic ban quet Yes Mortimer Giant Scalers other things besides fly big birds things eat info available Don Godfrey 91 Blackstone Ave Binghamton NY 13903 telephone 607 724-0115 Bob Beckman 8248 Holly Grove Ct Manassas VA 22110 RC Pylon Racing/Hager Continued page 54 does make wheel pants last longer Well doesnt shock actually destroys wheel pants eliminated attaching land ing gear General Electrics clear bath tub caulking compound assure get proper shock mount slide wheel pant up landing gear place caulking compound backside landing gear pant gear meet Slide back down line up hole gear pant clean unwant ed caulk away Caution Clean out screw hole could lock up wheels install Now assuming final attach ment ie wheel pants painted use Loc-Tite product secure wheels tighten down Allen wrench four-way wrench Place piece vinyl tape over hole unit complete experience using method has nothing convenience factor No special wrench tighten nut easy replacement easy paint touch-up lower-portion damage easy in-field repair replacement longer life wheel pants Hopefully experience will same See next mouth Bill Hager 706 Glen Haven Dr Conroe TX 77385 RC Helicopters/Jolly Continued page 55 really impressed some particular Airtronics 94554 heavyduty servo has proved excellent choice use Helicopter servo features coreless motor ball-bearingsupported output shaft good centering great strength Ive found servo particular value using flybarless rotor system Because heavy feed back loads some servos fail short time have putting lot hours set 94554s prototype GMP flybarless system over last nine months am very satisfied After reading above might think 94554 good flybarless machine quite contrary little thing works well under strenuous en vironment theyre better Bell Hiller system Another product found very useful American RCs new Lok N-Start starting system really dont like starting belts have admit starting cones work fine until starter slips off cone either goes through cabin adds burnished look finish Scale ship So what Lok-N-Start Basically unit consists two parts adapter shaft telescopes over starting shaft machine held place setscrews starter-adap ter another shaft screws onto end starter has Torrington clutch other end Starting accom plished inserting starter over adapter squeezing switch Because Torrington one-way clutch starter cannot keep engine ac celerating once have gotten fire Best off no friction necessary except transferred Torrington very clean simple system should have thought years ago works great months photos addition photo Jack Schultzs coaxial scratchbuilt have scratch-built-fuselage 152 ModelAviation
Edition: Model Aviation - 1985/05
Page Numbers: 52, 53, 152
Radio Control Giant Scale Bob Beckman GUEST COLUMNIST month am going turn space over John Hunton Several years ago before Giant Scale really became popular well-known John working engines RPVs Before us ever run across idea using chainsaw engines models John dai ly basis solving problems involved As result well qualified tell us. Rig Pumping Carburetors Flight John Hunton Industrial-type engines now popular larger model aircraft equipped carburetors designed operate dynamic environment flight notes explain what problems carburetors experience solve Problem No 1 Intake blow-off Most engines interest reed-valve type Note John quite correct statement Just maybe Big Bangers piston-port ed Quadras prime examples However conditions John describ ing can exist both types engine VyL IN2 INTAKE SK1 Carburetors generate wave fuel-en riched blow-back reverse Intake pulses AIR tLoW 5 bb reed close positive pres sure wave generated crankcase side reed Some positive charge flows back up intake out carburetor carburetor intake has open face strong flowof air over carburetor some t e fuel-enriched back-flow will blowin away replaced pure air ext intake pulse resulting leaner mixture see back-flow run engiie night protecting carburetor frothe airstream shine flashlight acro s open carburetor face See sket es No 1 No 2 representa tion f back-flow phenomenon T re some solutions blowoff roblem 1 Build cowling keep rstream off carburetor face solut could lead other problems er atmospheric pressure c rburetor senses changed abou later 2 Install velocity stack~ carburetor face contain l ack-flow next intake pulse see setch No 3the velocity stack can sometimes help engine runs inex plically rough 3 Install properly desiged air cleaner can contain b ck-flow well provide constant press re entrance venturi two very important functions beyond just keepiig gross impurities out intake Probem Na 2 Variations air pressure th venturi flow fuel intake air constant pressure venturi varied changes fuelair ratio will also vary have carburetors mounted face AIP PU-EAIIZ WPACi SK-2 fuel-enriched blow-back blown away replaced pure air thus causing lean condition gFAM2 AT %rnYE ANG1- intake vertical plane tunate setup changes angle pitch airframe during flight will change pressure carburetor face although changes velocity might see sketch No 4 Note respect best arrangement face carburetor parallel line offlight well vertical bb Carburetors mounted otherwise subject strong air pressure variations changes angle attack airframe see sketch No 5 solution both problems 1 2 build air cleaner functions contain back-flow control flow air across carbure tor face Sketch No 6 shows build such device Problem No 3 Variations fuel pres sure typical pumping carburetor amazingly insensitive fuel-level changes fuel tank vent-pressure variations problem design carbu retors however have pres sure-sensing port port provides ambient pressure level diaphragm mechanically compensates fuel flow changes barometric pressures caused altitude changes atmospheric pressure changes air moves across small hole see sketch No 7 changes pressure ingenious device sees Try playing air hose port engine running will observe changes fuel mixture fix problem simple Just provide protective cowling may V LOCJr- STACI cAnE-eTu NGIt SK 3 velocity stack can contain blow back next intake pulse A1-tI2AM AT f126AflV AN6L cF A7TAC 52 Model Aviation C 4 Variations angle attack enginelairframe have little effect pressure carburetor intake AIR ROW u - Al FAME POdTIVE AN&L CF ATTACI M NE6AThlE AN&- 9I ATT4Cr-. SK-5 Variations angle attack englnelairframe have significant effect upon air pressure carburetor intake job because possible pres sure changes within cowl certain fix duct port stable point pressure reference have fixed problems 1 2 building proper air cleaner will within carburetor take ahead venturi ducting can accomplished either internally sketch No 8 externally sketch No px 3 ALUMp IVIO63ALLM STANCAP L FrM EFQE E IV AtUM PLA7 r A5 *5INE SK-6 Air cisaner can contain biowback provide air prossure carb intake 9 depending design engine further note carburetors may interesting improve engine cowling potential ducting intake remote location recom mended because long intake can produce resonances will result uneven engine power output over operating rpm range summary pumping carburetor TAP ANP wrni 5HOT p EW SK-7 First step modifying pressure sensor carburetor INPOUT Ob3 C-HANHL HOLE HO& 00 0 00 K rjtI PLATE PHAM CovZ PLAT& SK8 Further steps modifying pressuresensor carb Read coiumn thorough description O2 7 can provide excellent air-fuel mixtures over wide variety rpm load condi tions proper provisions made environment carburetor operating Thats end Johns discourse Interesting no Coming attractions word starting come event scheduling year First RC Seaplane Fly-in Lakeport CA May 10-11-12 strictly Giant Scale event Giant Scale will probably dominate event will fund-raiser Statue Liberty restoration project Lee Taylor Event Director reports out standing cooperation local authorities site Californias Clearlake beautiful areas have ever seen hotbed both Giant Scale seaplane activity way can vicinity Continued page 152 4-0 o PaV TAP CtvZ L4T2 iwre caNN-r 5U TAPS INITVI QPL~ TLJ 116k Oe~ oC OLT$II kIgASM g PlATE SK9 final steps modifying carbs pressuresensor May 1985 53 / / // 7/ / L LJ 4 THE COMPETITIONS VIEW 'I OF THE WINDSONG I. C, 0 0 N 0 DODGSON DESIGNS 2904 SW CAMANO DRIVE CAMANO ISLAND WA 9825i2J What makes Windsong best plane have deadair lightlift gusting 25 MPH winds thermal contest What makes windsong best plane have x-country race Some say 11to 1 aspect ratio clean solidcore wing no spoiler bays disturb airflow Others say Eppler 214 airfoil combined exclusive full-span camber changing capability including elevator compensated 80 degree flaps reflexible ailerons fact design innovations contribute Windsongs total design concept its unprecedented performance WITH THE WINOSONG THE WHOLE IS TRULY GREATER THAN THE SUM OF ITS PARTS Windsong 19995Camano 15995Pixy 14995 Send 2 stamps catalog VHS video tape too can made readily-avail able materials youll have build some sophisticated electronics make work Please forward questions SASE author Happy Electric Landings Bob Kopski 25 West End Dr Lansdale PA 19446 RC Giant Scale/Beckman Continued page 53 dont miss information con tact Lee Taylor 216 Willow Ave Rose ville CA 95678 phone number 916 783-4190 next have information all-time favorite events STARS Scale Rally Olean NY scheduled July 6 7 year another event limited Giant Scale dont see much else flying site hospitality fantastic place might see Giant Scale aircraft IMAA Fun-Fly Festival IMAA bash year set July 18-21 Mobile AL fifth year event note time change August July Like Nats FFF rotating around different loca tions year like idea since gives IMAA members around country chance participate what Im hearing will another great Im putting weight just reading menus picnic ban quet Yes Mortimer Giant Scalers other things besides fly big birds things eat info available Don Godfrey 91 Blackstone Ave Binghamton NY 13903 telephone 607 724-0115 Bob Beckman 8248 Holly Grove Ct Manassas VA 22110 RC Pylon Racing/Hager Continued page 54 does make wheel pants last longer Well doesnt shock actually destroys wheel pants eliminated attaching land ing gear General Electrics clear bath tub caulking compound assure get proper shock mount slide wheel pant up landing gear place caulking compound backside landing gear pant gear meet Slide back down line up hole gear pant clean unwant ed caulk away Caution Clean out screw hole could lock up wheels install Now assuming final attach ment ie wheel pants painted use Loc-Tite product secure wheels tighten down Allen wrench four-way wrench Place piece vinyl tape over hole unit complete experience using method has nothing convenience factor No special wrench tighten nut easy replacement easy paint touch-up lower-portion damage easy in-field repair replacement longer life wheel pants Hopefully experience will same See next mouth Bill Hager 706 Glen Haven Dr Conroe TX 77385 RC Helicopters/Jolly Continued page 55 really impressed some particular Airtronics 94554 heavyduty servo has proved excellent choice use Helicopter servo features coreless motor ball-bearingsupported output shaft good centering great strength Ive found servo particular value using flybarless rotor system Because heavy feed back loads some servos fail short time have putting lot hours set 94554s prototype GMP flybarless system over last nine months am very satisfied After reading above might think 94554 good flybarless machine quite contrary little thing works well under strenuous en vironment theyre better Bell Hiller system Another product found very useful American RCs new Lok N-Start starting system really dont like starting belts have admit starting cones work fine until starter slips off cone either goes through cabin adds burnished look finish Scale ship So what Lok-N-Start Basically unit consists two parts adapter shaft telescopes over starting shaft machine held place setscrews starter-adap ter another shaft screws onto end starter has Torrington clutch other end Starting accom plished inserting starter over adapter squeezing switch Because Torrington one-way clutch starter cannot keep engine ac celerating once have gotten fire Best off no friction necessary except transferred Torrington very clean simple system should have thought years ago works great months photos addition photo Jack Schultzs coaxial scratchbuilt have scratch-built-fuselage 152 ModelAviation
Edition: Model Aviation - 1985/05
Page Numbers: 52, 53, 152
Radio Control Giant Scale Bob Beckman GUEST COLUMNIST month am going turn space over John Hunton Several years ago before Giant Scale really became popular well-known John working engines RPVs Before us ever run across idea using chainsaw engines models John dai ly basis solving problems involved As result well qualified tell us. Rig Pumping Carburetors Flight John Hunton Industrial-type engines now popular larger model aircraft equipped carburetors designed operate dynamic environment flight notes explain what problems carburetors experience solve Problem No 1 Intake blow-off Most engines interest reed-valve type Note John quite correct statement Just maybe Big Bangers piston-port ed Quadras prime examples However conditions John describ ing can exist both types engine VyL IN2 INTAKE SK1 Carburetors generate wave fuel-en riched blow-back reverse Intake pulses AIR tLoW 5 bb reed close positive pres sure wave generated crankcase side reed Some positive charge flows back up intake out carburetor carburetor intake has open face strong flowof air over carburetor some t e fuel-enriched back-flow will blowin away replaced pure air ext intake pulse resulting leaner mixture see back-flow run engiie night protecting carburetor frothe airstream shine flashlight acro s open carburetor face See sket es No 1 No 2 representa tion f back-flow phenomenon T re some solutions blowoff roblem 1 Build cowling keep rstream off carburetor face solut could lead other problems er atmospheric pressure c rburetor senses changed abou later 2 Install velocity stack~ carburetor face contain l ack-flow next intake pulse see setch No 3the velocity stack can sometimes help engine runs inex plically rough 3 Install properly desiged air cleaner can contain b ck-flow well provide constant press re entrance venturi two very important functions beyond just keepiig gross impurities out intake Probem Na 2 Variations air pressure th venturi flow fuel intake air constant pressure venturi varied changes fuelair ratio will also vary have carburetors mounted face AIP PU-EAIIZ WPACi SK-2 fuel-enriched blow-back blown away replaced pure air thus causing lean condition gFAM2 AT %rnYE ANG1- intake vertical plane tunate setup changes angle pitch airframe during flight will change pressure carburetor face although changes velocity might see sketch No 4 Note respect best arrangement face carburetor parallel line offlight well vertical bb Carburetors mounted otherwise subject strong air pressure variations changes angle attack airframe see sketch No 5 solution both problems 1 2 build air cleaner functions contain back-flow control flow air across carbure tor face Sketch No 6 shows build such device Problem No 3 Variations fuel pres sure typical pumping carburetor amazingly insensitive fuel-level changes fuel tank vent-pressure variations problem design carbu retors however have pres sure-sensing port port provides ambient pressure level diaphragm mechanically compensates fuel flow changes barometric pressures caused altitude changes atmospheric pressure changes air moves across small hole see sketch No 7 changes pressure ingenious device sees Try playing air hose port engine running will observe changes fuel mixture fix problem simple Just provide protective cowling may V LOCJr- STACI cAnE-eTu NGIt SK 3 velocity stack can contain blow back next intake pulse A1-tI2AM AT f126AflV AN6L cF A7TAC 52 Model Aviation C 4 Variations angle attack enginelairframe have little effect pressure carburetor intake AIR ROW u - Al FAME POdTIVE AN&L CF ATTACI M NE6AThlE AN&- 9I ATT4Cr-. SK-5 Variations angle attack englnelairframe have significant effect upon air pressure carburetor intake job because possible pres sure changes within cowl certain fix duct port stable point pressure reference have fixed problems 1 2 building proper air cleaner will within carburetor take ahead venturi ducting can accomplished either internally sketch No 8 externally sketch No px 3 ALUMp IVIO63ALLM STANCAP L FrM EFQE E IV AtUM PLA7 r A5 *5INE SK-6 Air cisaner can contain biowback provide air prossure carb intake 9 depending design engine further note carburetors may interesting improve engine cowling potential ducting intake remote location recom mended because long intake can produce resonances will result uneven engine power output over operating rpm range summary pumping carburetor TAP ANP wrni 5HOT p EW SK-7 First step modifying pressure sensor carburetor INPOUT Ob3 C-HANHL HOLE HO& 00 0 00 K rjtI PLATE PHAM CovZ PLAT& SK8 Further steps modifying pressuresensor carb Read coiumn thorough description O2 7 can provide excellent air-fuel mixtures over wide variety rpm load condi tions proper provisions made environment carburetor operating Thats end Johns discourse Interesting no Coming attractions word starting come event scheduling year First RC Seaplane Fly-in Lakeport CA May 10-11-12 strictly Giant Scale event Giant Scale will probably dominate event will fund-raiser Statue Liberty restoration project Lee Taylor Event Director reports out standing cooperation local authorities site Californias Clearlake beautiful areas have ever seen hotbed both Giant Scale seaplane activity way can vicinity Continued page 152 4-0 o PaV TAP CtvZ L4T2 iwre caNN-r 5U TAPS INITVI QPL~ TLJ 116k Oe~ oC OLT$II kIgASM g PlATE SK9 final steps modifying carbs pressuresensor May 1985 53 / / // 7/ / L LJ 4 THE COMPETITIONS VIEW 'I OF THE WINDSONG I. C, 0 0 N 0 DODGSON DESIGNS 2904 SW CAMANO DRIVE CAMANO ISLAND WA 9825i2J What makes Windsong best plane have deadair lightlift gusting 25 MPH winds thermal contest What makes windsong best plane have x-country race Some say 11to 1 aspect ratio clean solidcore wing no spoiler bays disturb airflow Others say Eppler 214 airfoil combined exclusive full-span camber changing capability including elevator compensated 80 degree flaps reflexible ailerons fact design innovations contribute Windsongs total design concept its unprecedented performance WITH THE WINOSONG THE WHOLE IS TRULY GREATER THAN THE SUM OF ITS PARTS Windsong 19995Camano 15995Pixy 14995 Send 2 stamps catalog VHS video tape too can made readily-avail able materials youll have build some sophisticated electronics make work Please forward questions SASE author Happy Electric Landings Bob Kopski 25 West End Dr Lansdale PA 19446 RC Giant Scale/Beckman Continued page 53 dont miss information con tact Lee Taylor 216 Willow Ave Rose ville CA 95678 phone number 916 783-4190 next have information all-time favorite events STARS Scale Rally Olean NY scheduled July 6 7 year another event limited Giant Scale dont see much else flying site hospitality fantastic place might see Giant Scale aircraft IMAA Fun-Fly Festival IMAA bash year set July 18-21 Mobile AL fifth year event note time change August July Like Nats FFF rotating around different loca tions year like idea since gives IMAA members around country chance participate what Im hearing will another great Im putting weight just reading menus picnic ban quet Yes Mortimer Giant Scalers other things besides fly big birds things eat info available Don Godfrey 91 Blackstone Ave Binghamton NY 13903 telephone 607 724-0115 Bob Beckman 8248 Holly Grove Ct Manassas VA 22110 RC Pylon Racing/Hager Continued page 54 does make wheel pants last longer Well doesnt shock actually destroys wheel pants eliminated attaching land ing gear General Electrics clear bath tub caulking compound assure get proper shock mount slide wheel pant up landing gear place caulking compound backside landing gear pant gear meet Slide back down line up hole gear pant clean unwant ed caulk away Caution Clean out screw hole could lock up wheels install Now assuming final attach ment ie wheel pants painted use Loc-Tite product secure wheels tighten down Allen wrench four-way wrench Place piece vinyl tape over hole unit complete experience using method has nothing convenience factor No special wrench tighten nut easy replacement easy paint touch-up lower-portion damage easy in-field repair replacement longer life wheel pants Hopefully experience will same See next mouth Bill Hager 706 Glen Haven Dr Conroe TX 77385 RC Helicopters/Jolly Continued page 55 really impressed some particular Airtronics 94554 heavyduty servo has proved excellent choice use Helicopter servo features coreless motor ball-bearingsupported output shaft good centering great strength Ive found servo particular value using flybarless rotor system Because heavy feed back loads some servos fail short time have putting lot hours set 94554s prototype GMP flybarless system over last nine months am very satisfied After reading above might think 94554 good flybarless machine quite contrary little thing works well under strenuous en vironment theyre better Bell Hiller system Another product found very useful American RCs new Lok N-Start starting system really dont like starting belts have admit starting cones work fine until starter slips off cone either goes through cabin adds burnished look finish Scale ship So what Lok-N-Start Basically unit consists two parts adapter shaft telescopes over starting shaft machine held place setscrews starter-adap ter another shaft screws onto end starter has Torrington clutch other end Starting accom plished inserting starter over adapter squeezing switch Because Torrington one-way clutch starter cannot keep engine ac celerating once have gotten fire Best off no friction necessary except transferred Torrington very clean simple system should have thought years ago works great months photos addition photo Jack Schultzs coaxial scratchbuilt have scratch-built-fuselage 152 ModelAviation