Preparing flight author engrossed plumbing Tanks two 48-oz plastic de tergent bottles extend 3 in front wing 6 behind Radio midway between wing stab hatch top fuse 652 mites PR G8LLOfl Setting new FAI Closed Course Record 225 miles 5 hours 38 minutes Tortoise landed 55% its fuel still tanks IN THE AUTUMN 1973 decided go after FAI distance duration rec ords completed satisfying summer pylon racing enough Quarter Midget races area World records offered new challenge first order business find engine would run economically engine tests initiated out set intended use diesel engine because runs longer glow com plication interference ignition ever engines tested glow since available An engine runs economically glow fuel should better diesel Articles found records set Bertrand Giertz Hill Hirota Kaiser Reed later Giertz engines used ranged 15 49 cu displacement After hours running about 20 different engines chose Supertigre 29 RV reasons choice since same basic crankcase used up 46 seemed should strong enough convert diesel Next time bone up aerody namics gathered books articles subject Perhaps useful book found Man Powered Flight Keith Sherwin problems considers quite similar encountered distance duration models viz designing fly minimum power Another valu able book dedicated modeler Fluid-Dynamic Drag S F Hoerner contains results great airplane drag experiments relevant model design third source informa Richard R Weber tion deserving attention give collection NACA annual reports 1920s 1930s three record categories stress ing fuel economy Duration Closed Course Distance Straight Line Distance Closed course distance chosen first cause requires smaller plane Du ration much easier undertaking driving several hundred miles back Straight Line Distance Straight Line Distance record also requires reliability because landing point must specified within 500 meters before take-off airplane went through numerous design stages keeping mind FAI limitations include maximum weight 1102 pounds maximum flying surface loading wing horizontal tail 2457 ounces per square foot maxi mum engine displacement 61 in3 Early sketches beautifully streamlined time construction began design become rather simple unlike its record-setting predecessors Its chief fea tures tapered wing genuine Clark Y airfoil built-up fuselage no formers cross braces fuselage filled firewall tail fuel radio components two fuel tanks made 48 oz plastic detergent bottles extending 3 front wing 5 behind hatch between wing stabilizer provides access radio model covered transparent Super Monokote assist visibility under various sky condi tions wing panel dark blue other yellow Experience has shown color other easily seen against sky background complete airA hefty shove important take-off assist record flight run about 600 feet Plane weighs 5 1/2 lbs fuel 10 1/2 loaded 652 Miles Per Gallon plane weighs 5 pounds fuel nearly I0/2 pounds fully fueled radio control system re liable compact easy battery check current drain several systems indicated Kraft 3-channel brick would ideal obtained brick converted transmit ter frequency 532 MHz Some addi tional work Doug Spreng Kraft Sys tems reduced servo current drain fur ther planned use rudder elevator controls third channel would available engine control needed batteries airborne radio sys tem four C cell nicads rated 15 AH found exceed 2 AH nicad transmitter battery pack good four five hours made interface box charge transmitter batteries power transmitter simultaneously contains meters monitor current voltage supplied transmitter also has potentiometer vary current interface box connects transmitter battery field box car battery used about half time during record flight During summer 1974 flew RC planes diesel engines order come familiar characteristics would like encourage much wider use diesels Contrary popular belief diesels start easily can throttled down like best glow engines Perhaps notable flight 1974 Septem ber 2 heavy Box Fly Jr powered Supertigre 15 R/C diesel took off ground flew engine running 1 hour 45 minutes four ounces fuel Initial flight tests new record model began December 23 1974 fuel cutoff connected third servo ending test hops tried variety likely 12V BATTERY 22h RANSMITTER 22h INTERFACE BOX propellers plane carrying two pounds water 11 ounces fuel Surprisingly little difference air speed found between different test props final choice Power Prop l-7 just like big pattern ship Later flights gradually increased fuel load ascertain whether shifting CG creased weight would present prob lems generally did fuel system consisted two pressu rized plastic tanks connected series fol lowed fuel pressure regulator Tests satisfactory although problem developed later May 10 1975 gathered official attempt FAI Closed Course Distance record sponsored Prince Georges RC Club Goddard MAC TIMED CRANKCASE PRESSURE SERVOPRESSURE CONTROLLEDREGULATOR VALVETANK 2 Present John Sites CD Luther Jack son Eric Baugher Ken Greenhouse Ron Moltz Chet Opal estimated chance success 50-50 since knew no problems plane never flown longer 75 minutes propitious day take-off 10plus-pound airplane ground looped went grass beside runway fuselage broke half behind wing brief discussion ensued Ron Moltz off home some Hot Stuff sticky Monokote amazement plane repaired flying half hour after returned official flight fifteen minutes old engine went lean slowed down repeatedly improved went leaii random fashion worried about FUEL SYSTEM TANK 10 OHMS ETER AMML TER DIODE Left After setting record designer displays airplane complete support system Size ship slightly larger pattern jobs Covering transparent Super Monokote Wing half blue half yellow colors show up best against sky background Right Radio Kraft 6-channel two-third brick airplane Engine Super Tigre R/C 15 Diesel conver sion Glow case proved inadequate sustained Diesel running very lean kept running Lap times running 52-54 seconds beginning soared over 70 seconds still ran After hour bad just decided stop worrying convinced would continue tor ment us day long engine stopped suddenly after 73 laps plane landed found rear engine bearing pushed out bottom crankcase theorized about several possible causes prob lem faulty regulator lean needle-valve setting causing overheating deposits piston crown raised com pression too high fatigue detona tion during earlier bench testing engine possible problems rectified regulator reworked needle valve hooked up servo con trol brand new crankcase found second attempt record June 14 1975 officials Luther Jackson CD Dean Smith Chet Opal Eric Baugher John Tallman Jerry Flynn Kirt Blattenberger After test flights adjust engine plane landed near tortoise walking run way immediately concluded good omen Since plane nameless dubbed Tortoise its slow steady flight tanks filled ground looping May reappeared plane took off fourth attempt after ground run about 600 feet old record 338 laps kilometers around course defined two pylons 500 meters apart Since FAI records must broken 2% magic number 345 laps flight went major problems Occasionally motor would go lean new mixture control took care Sometimes motor sounded fine would set leaner see would sag usually did immediately set richer again As nearing rec ord about lap 341 engine went quite lean needle valve quickly opened us held breath lap 345 completed round cheers record Result ground loop ending grass snapped fuselage Repairs took half hour Controls elevator rudder needle engine seemed happier probablyvalve Pressure fuel system used because concerned Talk ofhomemade regulator between tanks needle 400 500 laps began sound reason-valve Four C cell nicads supplied airborne ended abruptly end lap radio Transmitter pack good four ablefive hours Interface box permitted simulta 363 engine stopped warn- neous charging batteries power X-mitter ing plane glided smooth landing center course flown 363 continued page 70 010 II INCHES TORTOISE DISTANCE RECORD HOLDER RICHARD R WEBER 1975 November1975 37
Edition: Model Aviation - 1975/11
Page Numbers: 35, 36, 37
Preparing flight author engrossed plumbing Tanks two 48-oz plastic de tergent bottles extend 3 in front wing 6 behind Radio midway between wing stab hatch top fuse 652 mites PR G8LLOfl Setting new FAI Closed Course Record 225 miles 5 hours 38 minutes Tortoise landed 55% its fuel still tanks IN THE AUTUMN 1973 decided go after FAI distance duration rec ords completed satisfying summer pylon racing enough Quarter Midget races area World records offered new challenge first order business find engine would run economically engine tests initiated out set intended use diesel engine because runs longer glow com plication interference ignition ever engines tested glow since available An engine runs economically glow fuel should better diesel Articles found records set Bertrand Giertz Hill Hirota Kaiser Reed later Giertz engines used ranged 15 49 cu displacement After hours running about 20 different engines chose Supertigre 29 RV reasons choice since same basic crankcase used up 46 seemed should strong enough convert diesel Next time bone up aerody namics gathered books articles subject Perhaps useful book found Man Powered Flight Keith Sherwin problems considers quite similar encountered distance duration models viz designing fly minimum power Another valu able book dedicated modeler Fluid-Dynamic Drag S F Hoerner contains results great airplane drag experiments relevant model design third source informa Richard R Weber tion deserving attention give collection NACA annual reports 1920s 1930s three record categories stress ing fuel economy Duration Closed Course Distance Straight Line Distance Closed course distance chosen first cause requires smaller plane Du ration much easier undertaking driving several hundred miles back Straight Line Distance Straight Line Distance record also requires reliability because landing point must specified within 500 meters before take-off airplane went through numerous design stages keeping mind FAI limitations include maximum weight 1102 pounds maximum flying surface loading wing horizontal tail 2457 ounces per square foot maxi mum engine displacement 61 in3 Early sketches beautifully streamlined time construction began design become rather simple unlike its record-setting predecessors Its chief fea tures tapered wing genuine Clark Y airfoil built-up fuselage no formers cross braces fuselage filled firewall tail fuel radio components two fuel tanks made 48 oz plastic detergent bottles extending 3 front wing 5 behind hatch between wing stabilizer provides access radio model covered transparent Super Monokote assist visibility under various sky condi tions wing panel dark blue other yellow Experience has shown color other easily seen against sky background complete airA hefty shove important take-off assist record flight run about 600 feet Plane weighs 5 1/2 lbs fuel 10 1/2 loaded 652 Miles Per Gallon plane weighs 5 pounds fuel nearly I0/2 pounds fully fueled radio control system re liable compact easy battery check current drain several systems indicated Kraft 3-channel brick would ideal obtained brick converted transmit ter frequency 532 MHz Some addi tional work Doug Spreng Kraft Sys tems reduced servo current drain fur ther planned use rudder elevator controls third channel would available engine control needed batteries airborne radio sys tem four C cell nicads rated 15 AH found exceed 2 AH nicad transmitter battery pack good four five hours made interface box charge transmitter batteries power transmitter simultaneously contains meters monitor current voltage supplied transmitter also has potentiometer vary current interface box connects transmitter battery field box car battery used about half time during record flight During summer 1974 flew RC planes diesel engines order come familiar characteristics would like encourage much wider use diesels Contrary popular belief diesels start easily can throttled down like best glow engines Perhaps notable flight 1974 Septem ber 2 heavy Box Fly Jr powered Supertigre 15 R/C diesel took off ground flew engine running 1 hour 45 minutes four ounces fuel Initial flight tests new record model began December 23 1974 fuel cutoff connected third servo ending test hops tried variety likely 12V BATTERY 22h RANSMITTER 22h INTERFACE BOX propellers plane carrying two pounds water 11 ounces fuel Surprisingly little difference air speed found between different test props final choice Power Prop l-7 just like big pattern ship Later flights gradually increased fuel load ascertain whether shifting CG creased weight would present prob lems generally did fuel system consisted two pressu rized plastic tanks connected series fol lowed fuel pressure regulator Tests satisfactory although problem developed later May 10 1975 gathered official attempt FAI Closed Course Distance record sponsored Prince Georges RC Club Goddard MAC TIMED CRANKCASE PRESSURE SERVOPRESSURE CONTROLLEDREGULATOR VALVETANK 2 Present John Sites CD Luther Jack son Eric Baugher Ken Greenhouse Ron Moltz Chet Opal estimated chance success 50-50 since knew no problems plane never flown longer 75 minutes propitious day take-off 10plus-pound airplane ground looped went grass beside runway fuselage broke half behind wing brief discussion ensued Ron Moltz off home some Hot Stuff sticky Monokote amazement plane repaired flying half hour after returned official flight fifteen minutes old engine went lean slowed down repeatedly improved went leaii random fashion worried about FUEL SYSTEM TANK 10 OHMS ETER AMML TER DIODE Left After setting record designer displays airplane complete support system Size ship slightly larger pattern jobs Covering transparent Super Monokote Wing half blue half yellow colors show up best against sky background Right Radio Kraft 6-channel two-third brick airplane Engine Super Tigre R/C 15 Diesel conver sion Glow case proved inadequate sustained Diesel running very lean kept running Lap times running 52-54 seconds beginning soared over 70 seconds still ran After hour bad just decided stop worrying convinced would continue tor ment us day long engine stopped suddenly after 73 laps plane landed found rear engine bearing pushed out bottom crankcase theorized about several possible causes prob lem faulty regulator lean needle-valve setting causing overheating deposits piston crown raised com pression too high fatigue detona tion during earlier bench testing engine possible problems rectified regulator reworked needle valve hooked up servo con trol brand new crankcase found second attempt record June 14 1975 officials Luther Jackson CD Dean Smith Chet Opal Eric Baugher John Tallman Jerry Flynn Kirt Blattenberger After test flights adjust engine plane landed near tortoise walking run way immediately concluded good omen Since plane nameless dubbed Tortoise its slow steady flight tanks filled ground looping May reappeared plane took off fourth attempt after ground run about 600 feet old record 338 laps kilometers around course defined two pylons 500 meters apart Since FAI records must broken 2% magic number 345 laps flight went major problems Occasionally motor would go lean new mixture control took care Sometimes motor sounded fine would set leaner see would sag usually did immediately set richer again As nearing rec ord about lap 341 engine went quite lean needle valve quickly opened us held breath lap 345 completed round cheers record Result ground loop ending grass snapped fuselage Repairs took half hour Controls elevator rudder needle engine seemed happier probablyvalve Pressure fuel system used because concerned Talk ofhomemade regulator between tanks needle 400 500 laps began sound reason-valve Four C cell nicads supplied airborne ended abruptly end lap radio Transmitter pack good four ablefive hours Interface box permitted simulta 363 engine stopped warn- neous charging batteries power X-mitter ing plane glided smooth landing center course flown 363 continued page 70 010 II INCHES TORTOISE DISTANCE RECORD HOLDER RICHARD R WEBER 1975 November1975 37
Edition: Model Aviation - 1975/11
Page Numbers: 35, 36, 37
Preparing flight author engrossed plumbing Tanks two 48-oz plastic de tergent bottles extend 3 in front wing 6 behind Radio midway between wing stab hatch top fuse 652 mites PR G8LLOfl Setting new FAI Closed Course Record 225 miles 5 hours 38 minutes Tortoise landed 55% its fuel still tanks IN THE AUTUMN 1973 decided go after FAI distance duration rec ords completed satisfying summer pylon racing enough Quarter Midget races area World records offered new challenge first order business find engine would run economically engine tests initiated out set intended use diesel engine because runs longer glow com plication interference ignition ever engines tested glow since available An engine runs economically glow fuel should better diesel Articles found records set Bertrand Giertz Hill Hirota Kaiser Reed later Giertz engines used ranged 15 49 cu displacement After hours running about 20 different engines chose Supertigre 29 RV reasons choice since same basic crankcase used up 46 seemed should strong enough convert diesel Next time bone up aerody namics gathered books articles subject Perhaps useful book found Man Powered Flight Keith Sherwin problems considers quite similar encountered distance duration models viz designing fly minimum power Another valu able book dedicated modeler Fluid-Dynamic Drag S F Hoerner contains results great airplane drag experiments relevant model design third source informa Richard R Weber tion deserving attention give collection NACA annual reports 1920s 1930s three record categories stress ing fuel economy Duration Closed Course Distance Straight Line Distance Closed course distance chosen first cause requires smaller plane Du ration much easier undertaking driving several hundred miles back Straight Line Distance Straight Line Distance record also requires reliability because landing point must specified within 500 meters before take-off airplane went through numerous design stages keeping mind FAI limitations include maximum weight 1102 pounds maximum flying surface loading wing horizontal tail 2457 ounces per square foot maxi mum engine displacement 61 in3 Early sketches beautifully streamlined time construction began design become rather simple unlike its record-setting predecessors Its chief fea tures tapered wing genuine Clark Y airfoil built-up fuselage no formers cross braces fuselage filled firewall tail fuel radio components two fuel tanks made 48 oz plastic detergent bottles extending 3 front wing 5 behind hatch between wing stabilizer provides access radio model covered transparent Super Monokote assist visibility under various sky condi tions wing panel dark blue other yellow Experience has shown color other easily seen against sky background complete airA hefty shove important take-off assist record flight run about 600 feet Plane weighs 5 1/2 lbs fuel 10 1/2 loaded 652 Miles Per Gallon plane weighs 5 pounds fuel nearly I0/2 pounds fully fueled radio control system re liable compact easy battery check current drain several systems indicated Kraft 3-channel brick would ideal obtained brick converted transmit ter frequency 532 MHz Some addi tional work Doug Spreng Kraft Sys tems reduced servo current drain fur ther planned use rudder elevator controls third channel would available engine control needed batteries airborne radio sys tem four C cell nicads rated 15 AH found exceed 2 AH nicad transmitter battery pack good four five hours made interface box charge transmitter batteries power transmitter simultaneously contains meters monitor current voltage supplied transmitter also has potentiometer vary current interface box connects transmitter battery field box car battery used about half time during record flight During summer 1974 flew RC planes diesel engines order come familiar characteristics would like encourage much wider use diesels Contrary popular belief diesels start easily can throttled down like best glow engines Perhaps notable flight 1974 Septem ber 2 heavy Box Fly Jr powered Supertigre 15 R/C diesel took off ground flew engine running 1 hour 45 minutes four ounces fuel Initial flight tests new record model began December 23 1974 fuel cutoff connected third servo ending test hops tried variety likely 12V BATTERY 22h RANSMITTER 22h INTERFACE BOX propellers plane carrying two pounds water 11 ounces fuel Surprisingly little difference air speed found between different test props final choice Power Prop l-7 just like big pattern ship Later flights gradually increased fuel load ascertain whether shifting CG creased weight would present prob lems generally did fuel system consisted two pressu rized plastic tanks connected series fol lowed fuel pressure regulator Tests satisfactory although problem developed later May 10 1975 gathered official attempt FAI Closed Course Distance record sponsored Prince Georges RC Club Goddard MAC TIMED CRANKCASE PRESSURE SERVOPRESSURE CONTROLLEDREGULATOR VALVETANK 2 Present John Sites CD Luther Jack son Eric Baugher Ken Greenhouse Ron Moltz Chet Opal estimated chance success 50-50 since knew no problems plane never flown longer 75 minutes propitious day take-off 10plus-pound airplane ground looped went grass beside runway fuselage broke half behind wing brief discussion ensued Ron Moltz off home some Hot Stuff sticky Monokote amazement plane repaired flying half hour after returned official flight fifteen minutes old engine went lean slowed down repeatedly improved went leaii random fashion worried about FUEL SYSTEM TANK 10 OHMS ETER AMML TER DIODE Left After setting record designer displays airplane complete support system Size ship slightly larger pattern jobs Covering transparent Super Monokote Wing half blue half yellow colors show up best against sky background Right Radio Kraft 6-channel two-third brick airplane Engine Super Tigre R/C 15 Diesel conver sion Glow case proved inadequate sustained Diesel running very lean kept running Lap times running 52-54 seconds beginning soared over 70 seconds still ran After hour bad just decided stop worrying convinced would continue tor ment us day long engine stopped suddenly after 73 laps plane landed found rear engine bearing pushed out bottom crankcase theorized about several possible causes prob lem faulty regulator lean needle-valve setting causing overheating deposits piston crown raised com pression too high fatigue detona tion during earlier bench testing engine possible problems rectified regulator reworked needle valve hooked up servo con trol brand new crankcase found second attempt record June 14 1975 officials Luther Jackson CD Dean Smith Chet Opal Eric Baugher John Tallman Jerry Flynn Kirt Blattenberger After test flights adjust engine plane landed near tortoise walking run way immediately concluded good omen Since plane nameless dubbed Tortoise its slow steady flight tanks filled ground looping May reappeared plane took off fourth attempt after ground run about 600 feet old record 338 laps kilometers around course defined two pylons 500 meters apart Since FAI records must broken 2% magic number 345 laps flight went major problems Occasionally motor would go lean new mixture control took care Sometimes motor sounded fine would set leaner see would sag usually did immediately set richer again As nearing rec ord about lap 341 engine went quite lean needle valve quickly opened us held breath lap 345 completed round cheers record Result ground loop ending grass snapped fuselage Repairs took half hour Controls elevator rudder needle engine seemed happier probablyvalve Pressure fuel system used because concerned Talk ofhomemade regulator between tanks needle 400 500 laps began sound reason-valve Four C cell nicads supplied airborne ended abruptly end lap radio Transmitter pack good four ablefive hours Interface box permitted simulta 363 engine stopped warn- neous charging batteries power X-mitter ing plane glided smooth landing center course flown 363 continued page 70 010 II INCHES TORTOISE DISTANCE RECORD HOLDER RICHARD R WEBER 1975 November1975 37