John Preston Fiafety25 Comes First Peppertree Lu Sliver Spring MD 20906 II Watch compressed air/CO2 motors Ever have control stick come out hand re-treeving model airplanes COMPRESSED air/CO2 motors An interesting letter John Worth arrived last month described personal accident fortunately Out injury occurred experiment ing compressed air/CO2 motors Johns own words heres what happened have experimenting CO2 carbon dioxide motors couple years also past couple months compressed air mo tors Along way have combined technol ogies some interesting results Typical compressed air motors use initial pres sures 100 150 psi pounds per square inch Typical CO2 motors use perhaps 800 1000 psi Compressed air motors now commonly using plastic soda soft drink bottles anywhere three liters volume can appar ently handle up 175 200 psi pressure before bursting CO2 bottles actually better referred tanks made metal should able withstand pressures 3000 4000 psi before bursting What have doing using both air bottle CO2 tank model run mo tor Heres Pressurize air bottle about 120 psi air pressurize tank about 800 psi CO2 Between two have what effect needle valve normally prevents CO2 going air bottleuntil ready flight both systems charged normal pres sures start motorone flick prop does itusing air system motor runs rpm typically 3000 4000 rpm pro portional pressure use needle valve bleed CO2 air system re plenish air hold rpm essentially con stant small volume high pressure CO2 expands tremendously bleeds air bot tle typically triples length motor run suitable rpm over possible air alone So far good motor acts pressure regulator sorts varying its rpm according pressure going have getting ex cellent bench runs several months Free Flight Nats October ready some demonstrating flying other modelers see bunch us gathered gether prepared show what have ing seemed order filled air bot tle ran motor air alone No problem refilled air bottle started fill CO2 tank What didnt know should have needle valve between air CO2 systems fully closed As CO2 passed charging tank 5-lb fire extinguisher several us noticed snow flakes entering air bottle before dawned us what happening plastic bot tle exploded like cannon going off like cherry bomb Pieces model air bottle blew everywhere holding air bottle model next chest time ex plosion Several people within two three feet amazing nobody hurt al though felt like hit chest sledgehammer So model destroyed numb noise shock surprise Other wise nothing else amiss could have disaster Somebody particularly myself could have badly hurt think because air bottle probably blew something less 200 psi pressure force dispersed quickly plastic bottle broken up small pieces went very far So lucked out obviously matter needs further attention prevent anything like happening again first steps Pro vide interlock valve must fully closed before CO2 can put sys tem Also put pressure relief valve air system originally reliableobviously better needed Until minimal steps taken care am adding CO2 system Meanwhile anyone else might inclined try what have doing cautioned alert about what can happen unless adequate safety proce dures followed still think combining systems good idea motor performance standpoint has done safely Ill working problem will advise Im satisfied danger has controlled Readers might interested knowing reason soft drink manufacturers switched glass plastic containers larger Continued page 14 10 Model Aviation column provided address Items conceni regarding safety aspects model aviation activities Content column however opinion author does necessarily represent offidal posidon Academy Model Aeronautics 1 01-1 GOOD THE LEADER IN COMPETITION PROPELLERS NEW A CYCLE ES 100 THP DESIGN TAILORED HELICAL PITCH DEVELOPED TO GIVE MAXIMUM THRUST AT 4 CYCLE ENGINE RPM ALL THE LATEST TECHNIQUES USED ON OUR PRO SERIES 3 SEE BELOW DIA PITCH THP 1266778 136778 146778 1567 16678 NEW PRO SERIES 3 NEW HIGH TECH AIRFOIL SECTION 10T020% INCREASE IN THRUST MPG OF SELECT HARD MAPLE WOOD WILL NOT FATIGUE LIKE SYNTHETICS FUEL PROOF HIGH LUSTER FINISH DIAPITCH 5/a34 634 72633456 833/a4566 845667 9456677/s 1045667 106W6W 106EW 114677778 115W 116EW 1167 124W 125W 1256 1356 1456 1556 164N 16678 sizes liter up serious injuries caused glass bottles exploding Apparently some incidents occurred bottles sitting shelves supermarket Canadian government has mandatory reg ulation prohibiting large-size glass containers carbonated soft drinks wasnt necessary US because soft drink manufacturers made switch plastic bottles voluntarily Lit tle did know would also benefit com pressed air modelers old glass containers werent light enough use model they would also have ac cident waiting happen comment Johns experience hybrid air/CO2 system believe pres sure relief valve must model crash shortly after takeoff crash pre vented prop turning wouldnt take long CO2 build up sufficient pressure air bottle instantly destroy model Transmitter control stick failure Sandy Schmidt Brunswick ME unique experi ence flying friends model Over Sandy Several weeks ago fellow club member continuing testing prototype cabin biplane gorgeous well-built model flies sedately 29 diesel Al total about 30 flights model three particular day pits mentioned thought time see well would accomplish simple aerobatics Al asked fly plane through sedate sequence loops rollsperhaps plane pilot liked try spin Both us re checked control sensitivity range CG general airworthiness Al started diesel again checked throttle elevator rudder con trols taxi its tricycle gear perfect takeoff arrow-straight initial turns pat tern altitude disclosed no out-of-trim conditions Larger rectangular patterns showed no glitches introduction felt very comfortable new plane planned first loop roll ascertain control authority overlean out-of-trim conditions loop beautiful hesitation commenced roll maneuver completed just fine model returned back straight level just started turn back down wind another pass transmitter control stick came out hand bipe reason ably steady quickly making time away field yelled Al rudder/elevator con trol stick fell out ground After Id screamed second time got message started looking stick About time throttled back left en gine control stick jammed right thumb down right gimbal found some slight control plane made se ries sweeping S-turns back wind headed back toward field tried put control stick back gimbal Al said plastic broken Al suggested rather attempt run way landing might endanger spectators fellow pilots should gently crash land model out boonies seemed like great idea pulled throttle way back tried keep wings level let biplane settle two-foot-tall grass shrubs clay amazement other broken con trol stick discernible damage bro ken prop Al took apart transmitter epox ied stick back place model has since Continued page 18 PLANE TRACKER PILOT GLASSES Blocks 100% harmful UV rays High impact polycarbonate extra protect ion Dual gradient lens [Mirror Grayj Fit over prescription glasses Hard coated scratch resistance 1 year limited warranty Case included AVAILABLE IN Clear $1795 Amber $1995 Gray $1995 Mirror Gray $2495 CA Mask Paint Mask Banded Ear Plugs $1695 $2295 $795 {kBJl PLU5 See hobby dealer first doesni have what need order direct SAFETY PLUS P 0 Box 1173 Dept iM Clinton MS 39060 1-800-842-7233 Cant US 601924-9040 Satislaclion guaranteed Shipping handling included Add~for COD VISA1MC Only certified checks money orders accepted Minimum order S 12X Itiree packages ot4 Pomerpoles t250 per package $150 shipping handling CT residents add 75% salet tan Prices ouhiact change wiThout notice DEALER INDUINUS INVITED further ntcrmalrsr dealer prices send SASS Business Card SERMO R/C SNAP CONNECTORS Inc Cedar Corners Station Box 16787 Stamford CT 06905 1203322-6294 14 Model Aviation Wraparound style eliminates glare angles / RC PYLON RACING SERIES 500 DIA PITCH 7SN 5/aN 86/a778 SERIES 400C 8 66t/a77Vu7/a 9777 W WIDE BLADE EW EXTRA WIDE N NARROW very successfully flown several days have flying RC since 1958 have share battery radio motor prop fuel failures case reversed controls transmitter switch short reversed aile rons Aeromaster never did foresee transmitter stick falling out hand Ironically Sandys letter arrived mail same day experienced control failure problem parking brake release handle 1988 Taurus came out hand due ca ble breakage happened leaving work dark rainy night fortunate released parking brake before cable snapped others might have same experi ence fairly easy daylight see piece parking brake mechanism cable taches can reach down under dash board trip hand installing re placement cable $675 proved another mat ter Cars designed easily repaired Planes trees December 1990 Safety col umn mentioned modeler fell death attempting retrieve model tree asked readers better methods re trieving treed models climbing tree received some diverse suggestions noveland perhaps dangerous method came Bill Lang Chester IL Bill reports 100 percent success five model retrie vals very little damage planes shot off limbs tree model stranded says must use highvelocity rifle ensure bullet shatters passes through tree limb Slow bullets wont tend go off uncontrolled direc tions Maybe works Bill cant recom mend area miss tree limb bullet could threaten human life safer method came well-known Free Flighter Jim Scarborough served AMA Dis trict X VP years Jim uses bow shoot arrow over tree limb arrow tied light line used pull heavier line over limb shakes limb until model falls free may work cases treed mo dels think its lot safer blowing off limb bullet fired high-power rifle still have May 1989 issue Model Aviation will find article Joe Wagner make grabber retrieving mod els trees under 30 feet high Easy Way Out Trees grabber made electrical conduit features fork similar pitchfork its end grabbing model Joe Wagners model trapped 70ft-tall hickory called professional tree sur geon strongly recommend method George Wilson AMA District frequency coor dinator Warren Boudrie Pittaford NY Warrens letter described recent incident TR-260 made beautiful landing top 50-ft tree looked yellow pages under Tree Service located professional tree man responded within two hours Using appropriate climbing gear professional scaled tree lowered model ground damage small tear covering material cost recovery $35well worth opinion George Wilson noted should never re trieve model chopping down tree could dangerous both tree chopper model Its also likely illegal area Continued page 140 18 Model Aviation BILL WINTERS RIC SPECIAL Bills latest design offers rock steady stability solid realistic flight performance Special design concept originated 1947 publicity Mechanics Illustrated 1948 over years has evolved optimized flyer new specially designed semi-symmetrical airfoil contributes smoothness response behavior aspects its air worthiness Special fully aerobatic yet offers broad spectrum performance speeds Optional flaps 4-5 channel radio 45-50 twocycle 46-60 four cycle 40-60 electric 61 span 642 sq area 5-6 lbs flying weight Diamond airfoil stabilizer FEATURES Tempered aluminum landing gear ABS molded cowl hardware package full size rolled plans photo illustrated step-by-step instructions windshield window material accurately machine die cut selected balsa spruce plywood flexible steel cable V ailleron control IPAVEY675 TOWER LANE YSTEMS WEST CHESTER PA 19380 4 oRPoRATIoN 215-430-8645 words went lean has used least understood phrases modeling today seems time model motor loses power accusation went lean several reasons motor could slow down possibly quit properly broken-in model motor running right fuel plug properly cooled does sag heat up fuel level dropped too far needle tweaked too fan What should happen motor just slows very slightly quits firing cases motor sags down cooks three probable causes crankshaft bearings getting enough cooling fuel heat up start dragging 2 cylinder piston dont have enough clearance start binding 3 usual cause motor starts pre-igniting motor leaned makes power also makes heat makes heat plug element gets hotter ignition starts occurring soonen motor has little extra heat added because being new creating friction because weather hot because thefuel has too much nitro because glow plug retains too much heat motor can come up critical point ignition starts too soon over-advanced ignition combustion pressure presses piston down part up stroke turn generates morefriction heat again further aggravates pre-ignition problem Most model motors set up will run very close pre-ignition point because way get power Once motor goes over power peak way get back throttle back cool off Remember start lean motor get maximum power motor warms up seems slow down suffering pre-ignition slight bit pre-ignition dead lean setting may too bad because way usually get power out motor However much sagging dead lean setting giving away too much rich lean tolerance motor something should done Switching cooler running plug helps Reducing nitro fuel can make lot difference Adding little oil fuel can help some put together reasonable quantities isnt enough reducing compression ratio orden Unfortunately see lot cases pre ignition days reasons nitro expensive afrw years back people thinking nitro means power will order expensive fuel bad idea carry around can FAI type fuel 4 parts straight alcohol part straight castor next time ofyourflying buddies experiences leaning out tendency try cutting yourfuel FAI mixture see doesnt help ofyou may have experienced thrill offlying Fox motor would like no risk make offer will loan either Fox 40 Standard Eagle 60 choice Fly own airplane After 30 days return motor us pay UPS charges back would want Visa MasterCard number would charge motor returned Cant beat deal like can Happy flying anufacturing Company 5305 Towson Avenue FOX Fort Smith AR 72901 Phone 501 6461656 Safety/Preston Continued page 18 CyA glue eye letter Mark Miller El Segundo CA related painful conse quences getting drop cyanoacrylate CyA glue eye Mark gluing split piece balsawood two sides split sud denly snapped together ejected droplet glue landed cornea immediately cured emergency room nice mans gave him local anesthetic muscle relaxant could open eye again Ive previously mentioned incidents similar Marks can painful experience Ive never heard lasting injury Mark added incident drew atten tion interesting flaw medical coverage thats another story Im assuming shell out some bucks hospital visit Accidents can injure financially too Thats something dont always think about till hap pens Clarification letter Clair Sieverling pointed out original author tongue-in-cheek segment December 1990 Safety column called History Balsa Wood Model Aviation Clair Phoenix AZ wrote am original author piece non sense wrote editor Arizona Model Pilots Society AMPS newslet ter Prop Nut printed September 1985 issue thereof Thank Clair set ting record straight Have another safe month Flying Fun/Mathews Continued page 20 some other recreational activity others like have plugging away hobby years Bill thought moment Ive never learned NEW STARHAWK BIPLANE NEW MISS STARHAWK POSTER See your Starhawk Dealer details write Thorpe Engineering Corporation 1715 E Fairfield Mesa AZ 85203 Poster $500 P&H Prepaid riginal EZ UP Sun Shelters a8x 8 * Sturdy Steel Frames Heavy Duty Fade Resistant Nylon 1OX1OCanopies RedWhlte Blue alOx 15Sets Up less 60 Seconds Authorized -Z UP Corp DealerNo Rope Nothing Assemble John Peck Leisure Products Ltd *IMAA 3287 AMA 8580131 Ravenwood Road Other Sizes Colors Versailles KY 40383 Accessories Avallsble Plu •Custom Logos LetteringWrite1606 873-5172 140 Model Aviation CHECK EM BOTH OUT
Edition: Model Aviation - 1991/02
Page Numbers: 10, 14, 18, 140
Edition: Model Aviation - 1991/02
Page Numbers: 10, 14, 18, 140
John Preston Fiafety25 Comes First Peppertree Lu Sliver Spring MD 20906 II Watch compressed air/CO2 motors Ever have control stick come out hand re-treeving model airplanes COMPRESSED air/CO2 motors An interesting letter John Worth arrived last month described personal accident fortunately Out injury occurred experiment ing compressed air/CO2 motors Johns own words heres what happened have experimenting CO2 carbon dioxide motors couple years also past couple months compressed air mo tors Along way have combined technol ogies some interesting results Typical compressed air motors use initial pres sures 100 150 psi pounds per square inch Typical CO2 motors use perhaps 800 1000 psi Compressed air motors now commonly using plastic soda soft drink bottles anywhere three liters volume can appar ently handle up 175 200 psi pressure before bursting CO2 bottles actually better referred tanks made metal should able withstand pressures 3000 4000 psi before bursting What have doing using both air bottle CO2 tank model run mo tor Heres Pressurize air bottle about 120 psi air pressurize tank about 800 psi CO2 Between two have what effect needle valve normally prevents CO2 going air bottleuntil ready flight both systems charged normal pres sures start motorone flick prop does itusing air system motor runs rpm typically 3000 4000 rpm pro portional pressure use needle valve bleed CO2 air system re plenish air hold rpm essentially con stant small volume high pressure CO2 expands tremendously bleeds air bot tle typically triples length motor run suitable rpm over possible air alone So far good motor acts pressure regulator sorts varying its rpm according pressure going have getting ex cellent bench runs several months Free Flight Nats October ready some demonstrating flying other modelers see bunch us gathered gether prepared show what have ing seemed order filled air bot tle ran motor air alone No problem refilled air bottle started fill CO2 tank What didnt know should have needle valve between air CO2 systems fully closed As CO2 passed charging tank 5-lb fire extinguisher several us noticed snow flakes entering air bottle before dawned us what happening plastic bot tle exploded like cannon going off like cherry bomb Pieces model air bottle blew everywhere holding air bottle model next chest time ex plosion Several people within two three feet amazing nobody hurt al though felt like hit chest sledgehammer So model destroyed numb noise shock surprise Other wise nothing else amiss could have disaster Somebody particularly myself could have badly hurt think because air bottle probably blew something less 200 psi pressure force dispersed quickly plastic bottle broken up small pieces went very far So lucked out obviously matter needs further attention prevent anything like happening again first steps Pro vide interlock valve must fully closed before CO2 can put sys tem Also put pressure relief valve air system originally reliableobviously better needed Until minimal steps taken care am adding CO2 system Meanwhile anyone else might inclined try what have doing cautioned alert about what can happen unless adequate safety proce dures followed still think combining systems good idea motor performance standpoint has done safely Ill working problem will advise Im satisfied danger has controlled Readers might interested knowing reason soft drink manufacturers switched glass plastic containers larger Continued page 14 10 Model Aviation column provided address Items conceni regarding safety aspects model aviation activities Content column however opinion author does necessarily represent offidal posidon Academy Model Aeronautics 1 01-1 GOOD THE LEADER IN COMPETITION PROPELLERS NEW A CYCLE ES 100 THP DESIGN TAILORED HELICAL PITCH DEVELOPED TO GIVE MAXIMUM THRUST AT 4 CYCLE ENGINE RPM ALL THE LATEST TECHNIQUES USED ON OUR PRO SERIES 3 SEE BELOW DIA PITCH THP 1266778 136778 146778 1567 16678 NEW PRO SERIES 3 NEW HIGH TECH AIRFOIL SECTION 10T020% INCREASE IN THRUST MPG OF SELECT HARD MAPLE WOOD WILL NOT FATIGUE LIKE SYNTHETICS FUEL PROOF HIGH LUSTER FINISH DIAPITCH 5/a34 634 72633456 833/a4566 845667 9456677/s 1045667 106W6W 106EW 114677778 115W 116EW 1167 124W 125W 1256 1356 1456 1556 164N 16678 sizes liter up serious injuries caused glass bottles exploding Apparently some incidents occurred bottles sitting shelves supermarket Canadian government has mandatory reg ulation prohibiting large-size glass containers carbonated soft drinks wasnt necessary US because soft drink manufacturers made switch plastic bottles voluntarily Lit tle did know would also benefit com pressed air modelers old glass containers werent light enough use model they would also have ac cident waiting happen comment Johns experience hybrid air/CO2 system believe pres sure relief valve must model crash shortly after takeoff crash pre vented prop turning wouldnt take long CO2 build up sufficient pressure air bottle instantly destroy model Transmitter control stick failure Sandy Schmidt Brunswick ME unique experi ence flying friends model Over Sandy Several weeks ago fellow club member continuing testing prototype cabin biplane gorgeous well-built model flies sedately 29 diesel Al total about 30 flights model three particular day pits mentioned thought time see well would accomplish simple aerobatics Al asked fly plane through sedate sequence loops rollsperhaps plane pilot liked try spin Both us re checked control sensitivity range CG general airworthiness Al started diesel again checked throttle elevator rudder con trols taxi its tricycle gear perfect takeoff arrow-straight initial turns pat tern altitude disclosed no out-of-trim conditions Larger rectangular patterns showed no glitches introduction felt very comfortable new plane planned first loop roll ascertain control authority overlean out-of-trim conditions loop beautiful hesitation commenced roll maneuver completed just fine model returned back straight level just started turn back down wind another pass transmitter control stick came out hand bipe reason ably steady quickly making time away field yelled Al rudder/elevator con trol stick fell out ground After Id screamed second time got message started looking stick About time throttled back left en gine control stick jammed right thumb down right gimbal found some slight control plane made se ries sweeping S-turns back wind headed back toward field tried put control stick back gimbal Al said plastic broken Al suggested rather attempt run way landing might endanger spectators fellow pilots should gently crash land model out boonies seemed like great idea pulled throttle way back tried keep wings level let biplane settle two-foot-tall grass shrubs clay amazement other broken con trol stick discernible damage bro ken prop Al took apart transmitter epox ied stick back place model has since Continued page 18 PLANE TRACKER PILOT GLASSES Blocks 100% harmful UV rays High impact polycarbonate extra protect ion Dual gradient lens [Mirror Grayj Fit over prescription glasses Hard coated scratch resistance 1 year limited warranty Case included AVAILABLE IN Clear $1795 Amber $1995 Gray $1995 Mirror Gray $2495 CA Mask Paint Mask Banded Ear Plugs $1695 $2295 $795 {kBJl PLU5 See hobby dealer first doesni have what need order direct SAFETY PLUS P 0 Box 1173 Dept iM Clinton MS 39060 1-800-842-7233 Cant US 601924-9040 Satislaclion guaranteed Shipping handling included Add~for COD VISA1MC Only certified checks money orders accepted Minimum order S 12X Itiree packages ot4 Pomerpoles t250 per package $150 shipping handling CT residents add 75% salet tan Prices ouhiact change wiThout notice DEALER INDUINUS INVITED further ntcrmalrsr dealer prices send SASS Business Card SERMO R/C SNAP CONNECTORS Inc Cedar Corners Station Box 16787 Stamford CT 06905 1203322-6294 14 Model Aviation Wraparound style eliminates glare angles / RC PYLON RACING SERIES 500 DIA PITCH 7SN 5/aN 86/a778 SERIES 400C 8 66t/a77Vu7/a 9777 W WIDE BLADE EW EXTRA WIDE N NARROW very successfully flown several days have flying RC since 1958 have share battery radio motor prop fuel failures case reversed controls transmitter switch short reversed aile rons Aeromaster never did foresee transmitter stick falling out hand Ironically Sandys letter arrived mail same day experienced control failure problem parking brake release handle 1988 Taurus came out hand due ca ble breakage happened leaving work dark rainy night fortunate released parking brake before cable snapped others might have same experi ence fairly easy daylight see piece parking brake mechanism cable taches can reach down under dash board trip hand installing re placement cable $675 proved another mat ter Cars designed easily repaired Planes trees December 1990 Safety col umn mentioned modeler fell death attempting retrieve model tree asked readers better methods re trieving treed models climbing tree received some diverse suggestions noveland perhaps dangerous method came Bill Lang Chester IL Bill reports 100 percent success five model retrie vals very little damage planes shot off limbs tree model stranded says must use highvelocity rifle ensure bullet shatters passes through tree limb Slow bullets wont tend go off uncontrolled direc tions Maybe works Bill cant recom mend area miss tree limb bullet could threaten human life safer method came well-known Free Flighter Jim Scarborough served AMA Dis trict X VP years Jim uses bow shoot arrow over tree limb arrow tied light line used pull heavier line over limb shakes limb until model falls free may work cases treed mo dels think its lot safer blowing off limb bullet fired high-power rifle still have May 1989 issue Model Aviation will find article Joe Wagner make grabber retrieving mod els trees under 30 feet high Easy Way Out Trees grabber made electrical conduit features fork similar pitchfork its end grabbing model Joe Wagners model trapped 70ft-tall hickory called professional tree sur geon strongly recommend method George Wilson AMA District frequency coor dinator Warren Boudrie Pittaford NY Warrens letter described recent incident TR-260 made beautiful landing top 50-ft tree looked yellow pages under Tree Service located professional tree man responded within two hours Using appropriate climbing gear professional scaled tree lowered model ground damage small tear covering material cost recovery $35well worth opinion George Wilson noted should never re trieve model chopping down tree could dangerous both tree chopper model Its also likely illegal area Continued page 140 18 Model Aviation BILL WINTERS RIC SPECIAL Bills latest design offers rock steady stability solid realistic flight performance Special design concept originated 1947 publicity Mechanics Illustrated 1948 over years has evolved optimized flyer new specially designed semi-symmetrical airfoil contributes smoothness response behavior aspects its air worthiness Special fully aerobatic yet offers broad spectrum performance speeds Optional flaps 4-5 channel radio 45-50 twocycle 46-60 four cycle 40-60 electric 61 span 642 sq area 5-6 lbs flying weight Diamond airfoil stabilizer FEATURES Tempered aluminum landing gear ABS molded cowl hardware package full size rolled plans photo illustrated step-by-step instructions windshield window material accurately machine die cut selected balsa spruce plywood flexible steel cable V ailleron control IPAVEY675 TOWER LANE YSTEMS WEST CHESTER PA 19380 4 oRPoRATIoN 215-430-8645 words went lean has used least understood phrases modeling today seems time model motor loses power accusation went lean several reasons motor could slow down possibly quit properly broken-in model motor running right fuel plug properly cooled does sag heat up fuel level dropped too far needle tweaked too fan What should happen motor just slows very slightly quits firing cases motor sags down cooks three probable causes crankshaft bearings getting enough cooling fuel heat up start dragging 2 cylinder piston dont have enough clearance start binding 3 usual cause motor starts pre-igniting motor leaned makes power also makes heat makes heat plug element gets hotter ignition starts occurring soonen motor has little extra heat added because being new creating friction because weather hot because thefuel has too much nitro because glow plug retains too much heat motor can come up critical point ignition starts too soon over-advanced ignition combustion pressure presses piston down part up stroke turn generates morefriction heat again further aggravates pre-ignition problem Most model motors set up will run very close pre-ignition point because way get power Once motor goes over power peak way get back throttle back cool off Remember start lean motor get maximum power motor warms up seems slow down suffering pre-ignition slight bit pre-ignition dead lean setting may too bad because way usually get power out motor However much sagging dead lean setting giving away too much rich lean tolerance motor something should done Switching cooler running plug helps Reducing nitro fuel can make lot difference Adding little oil fuel can help some put together reasonable quantities isnt enough reducing compression ratio orden Unfortunately see lot cases pre ignition days reasons nitro expensive afrw years back people thinking nitro means power will order expensive fuel bad idea carry around can FAI type fuel 4 parts straight alcohol part straight castor next time ofyourflying buddies experiences leaning out tendency try cutting yourfuel FAI mixture see doesnt help ofyou may have experienced thrill offlying Fox motor would like no risk make offer will loan either Fox 40 Standard Eagle 60 choice Fly own airplane After 30 days return motor us pay UPS charges back would want Visa MasterCard number would charge motor returned Cant beat deal like can Happy flying anufacturing Company 5305 Towson Avenue FOX Fort Smith AR 72901 Phone 501 6461656 Safety/Preston Continued page 18 CyA glue eye letter Mark Miller El Segundo CA related painful conse quences getting drop cyanoacrylate CyA glue eye Mark gluing split piece balsawood two sides split sud denly snapped together ejected droplet glue landed cornea immediately cured emergency room nice mans gave him local anesthetic muscle relaxant could open eye again Ive previously mentioned incidents similar Marks can painful experience Ive never heard lasting injury Mark added incident drew atten tion interesting flaw medical coverage thats another story Im assuming shell out some bucks hospital visit Accidents can injure financially too Thats something dont always think about till hap pens Clarification letter Clair Sieverling pointed out original author tongue-in-cheek segment December 1990 Safety column called History Balsa Wood Model Aviation Clair Phoenix AZ wrote am original author piece non sense wrote editor Arizona Model Pilots Society AMPS newslet ter Prop Nut printed September 1985 issue thereof Thank Clair set ting record straight Have another safe month Flying Fun/Mathews Continued page 20 some other recreational activity others like have plugging away hobby years Bill thought moment Ive never learned NEW STARHAWK BIPLANE NEW MISS STARHAWK POSTER See your Starhawk Dealer details write Thorpe Engineering Corporation 1715 E Fairfield Mesa AZ 85203 Poster $500 P&H Prepaid riginal EZ UP Sun Shelters a8x 8 * Sturdy Steel Frames Heavy Duty Fade Resistant Nylon 1OX1OCanopies RedWhlte Blue alOx 15Sets Up less 60 Seconds Authorized -Z UP Corp DealerNo Rope Nothing Assemble John Peck Leisure Products Ltd *IMAA 3287 AMA 8580131 Ravenwood Road Other Sizes Colors Versailles KY 40383 Accessories Avallsble Plu •Custom Logos LetteringWrite1606 873-5172 140 Model Aviation CHECK EM BOTH OUT
Edition: Model Aviation - 1991/02
Page Numbers: 10, 14, 18, 140
John Preston Fiafety25 Comes First Peppertree Lu Sliver Spring MD 20906 II Watch compressed air/CO2 motors Ever have control stick come out hand re-treeving model airplanes COMPRESSED air/CO2 motors An interesting letter John Worth arrived last month described personal accident fortunately Out injury occurred experiment ing compressed air/CO2 motors Johns own words heres what happened have experimenting CO2 carbon dioxide motors couple years also past couple months compressed air mo tors Along way have combined technol ogies some interesting results Typical compressed air motors use initial pres sures 100 150 psi pounds per square inch Typical CO2 motors use perhaps 800 1000 psi Compressed air motors now commonly using plastic soda soft drink bottles anywhere three liters volume can appar ently handle up 175 200 psi pressure before bursting CO2 bottles actually better referred tanks made metal should able withstand pressures 3000 4000 psi before bursting What have doing using both air bottle CO2 tank model run mo tor Heres Pressurize air bottle about 120 psi air pressurize tank about 800 psi CO2 Between two have what effect needle valve normally prevents CO2 going air bottleuntil ready flight both systems charged normal pres sures start motorone flick prop does itusing air system motor runs rpm typically 3000 4000 rpm pro portional pressure use needle valve bleed CO2 air system re plenish air hold rpm essentially con stant small volume high pressure CO2 expands tremendously bleeds air bot tle typically triples length motor run suitable rpm over possible air alone So far good motor acts pressure regulator sorts varying its rpm according pressure going have getting ex cellent bench runs several months Free Flight Nats October ready some demonstrating flying other modelers see bunch us gathered gether prepared show what have ing seemed order filled air bot tle ran motor air alone No problem refilled air bottle started fill CO2 tank What didnt know should have needle valve between air CO2 systems fully closed As CO2 passed charging tank 5-lb fire extinguisher several us noticed snow flakes entering air bottle before dawned us what happening plastic bot tle exploded like cannon going off like cherry bomb Pieces model air bottle blew everywhere holding air bottle model next chest time ex plosion Several people within two three feet amazing nobody hurt al though felt like hit chest sledgehammer So model destroyed numb noise shock surprise Other wise nothing else amiss could have disaster Somebody particularly myself could have badly hurt think because air bottle probably blew something less 200 psi pressure force dispersed quickly plastic bottle broken up small pieces went very far So lucked out obviously matter needs further attention prevent anything like happening again first steps Pro vide interlock valve must fully closed before CO2 can put sys tem Also put pressure relief valve air system originally reliableobviously better needed Until minimal steps taken care am adding CO2 system Meanwhile anyone else might inclined try what have doing cautioned alert about what can happen unless adequate safety proce dures followed still think combining systems good idea motor performance standpoint has done safely Ill working problem will advise Im satisfied danger has controlled Readers might interested knowing reason soft drink manufacturers switched glass plastic containers larger Continued page 14 10 Model Aviation column provided address Items conceni regarding safety aspects model aviation activities Content column however opinion author does necessarily represent offidal posidon Academy Model Aeronautics 1 01-1 GOOD THE LEADER IN COMPETITION PROPELLERS NEW A CYCLE ES 100 THP DESIGN TAILORED HELICAL PITCH DEVELOPED TO GIVE MAXIMUM THRUST AT 4 CYCLE ENGINE RPM ALL THE LATEST TECHNIQUES USED ON OUR PRO SERIES 3 SEE BELOW DIA PITCH THP 1266778 136778 146778 1567 16678 NEW PRO SERIES 3 NEW HIGH TECH AIRFOIL SECTION 10T020% INCREASE IN THRUST MPG OF SELECT HARD MAPLE WOOD WILL NOT FATIGUE LIKE SYNTHETICS FUEL PROOF HIGH LUSTER FINISH DIAPITCH 5/a34 634 72633456 833/a4566 845667 9456677/s 1045667 106W6W 106EW 114677778 115W 116EW 1167 124W 125W 1256 1356 1456 1556 164N 16678 sizes liter up serious injuries caused glass bottles exploding Apparently some incidents occurred bottles sitting shelves supermarket Canadian government has mandatory reg ulation prohibiting large-size glass containers carbonated soft drinks wasnt necessary US because soft drink manufacturers made switch plastic bottles voluntarily Lit tle did know would also benefit com pressed air modelers old glass containers werent light enough use model they would also have ac cident waiting happen comment Johns experience hybrid air/CO2 system believe pres sure relief valve must model crash shortly after takeoff crash pre vented prop turning wouldnt take long CO2 build up sufficient pressure air bottle instantly destroy model Transmitter control stick failure Sandy Schmidt Brunswick ME unique experi ence flying friends model Over Sandy Several weeks ago fellow club member continuing testing prototype cabin biplane gorgeous well-built model flies sedately 29 diesel Al total about 30 flights model three particular day pits mentioned thought time see well would accomplish simple aerobatics Al asked fly plane through sedate sequence loops rollsperhaps plane pilot liked try spin Both us re checked control sensitivity range CG general airworthiness Al started diesel again checked throttle elevator rudder con trols taxi its tricycle gear perfect takeoff arrow-straight initial turns pat tern altitude disclosed no out-of-trim conditions Larger rectangular patterns showed no glitches introduction felt very comfortable new plane planned first loop roll ascertain control authority overlean out-of-trim conditions loop beautiful hesitation commenced roll maneuver completed just fine model returned back straight level just started turn back down wind another pass transmitter control stick came out hand bipe reason ably steady quickly making time away field yelled Al rudder/elevator con trol stick fell out ground After Id screamed second time got message started looking stick About time throttled back left en gine control stick jammed right thumb down right gimbal found some slight control plane made se ries sweeping S-turns back wind headed back toward field tried put control stick back gimbal Al said plastic broken Al suggested rather attempt run way landing might endanger spectators fellow pilots should gently crash land model out boonies seemed like great idea pulled throttle way back tried keep wings level let biplane settle two-foot-tall grass shrubs clay amazement other broken con trol stick discernible damage bro ken prop Al took apart transmitter epox ied stick back place model has since Continued page 18 PLANE TRACKER PILOT GLASSES Blocks 100% harmful UV rays High impact polycarbonate extra protect ion Dual gradient lens [Mirror Grayj Fit over prescription glasses Hard coated scratch resistance 1 year limited warranty Case included AVAILABLE IN Clear $1795 Amber $1995 Gray $1995 Mirror Gray $2495 CA Mask Paint Mask Banded Ear Plugs $1695 $2295 $795 {kBJl PLU5 See hobby dealer first doesni have what need order direct SAFETY PLUS P 0 Box 1173 Dept iM Clinton MS 39060 1-800-842-7233 Cant US 601924-9040 Satislaclion guaranteed Shipping handling included Add~for COD VISA1MC Only certified checks money orders accepted Minimum order S 12X Itiree packages ot4 Pomerpoles t250 per package $150 shipping handling CT residents add 75% salet tan Prices ouhiact change wiThout notice DEALER INDUINUS INVITED further ntcrmalrsr dealer prices send SASS Business Card SERMO R/C SNAP CONNECTORS Inc Cedar Corners Station Box 16787 Stamford CT 06905 1203322-6294 14 Model Aviation Wraparound style eliminates glare angles / RC PYLON RACING SERIES 500 DIA PITCH 7SN 5/aN 86/a778 SERIES 400C 8 66t/a77Vu7/a 9777 W WIDE BLADE EW EXTRA WIDE N NARROW very successfully flown several days have flying RC since 1958 have share battery radio motor prop fuel failures case reversed controls transmitter switch short reversed aile rons Aeromaster never did foresee transmitter stick falling out hand Ironically Sandys letter arrived mail same day experienced control failure problem parking brake release handle 1988 Taurus came out hand due ca ble breakage happened leaving work dark rainy night fortunate released parking brake before cable snapped others might have same experi ence fairly easy daylight see piece parking brake mechanism cable taches can reach down under dash board trip hand installing re placement cable $675 proved another mat ter Cars designed easily repaired Planes trees December 1990 Safety col umn mentioned modeler fell death attempting retrieve model tree asked readers better methods re trieving treed models climbing tree received some diverse suggestions noveland perhaps dangerous method came Bill Lang Chester IL Bill reports 100 percent success five model retrie vals very little damage planes shot off limbs tree model stranded says must use highvelocity rifle ensure bullet shatters passes through tree limb Slow bullets wont tend go off uncontrolled direc tions Maybe works Bill cant recom mend area miss tree limb bullet could threaten human life safer method came well-known Free Flighter Jim Scarborough served AMA Dis trict X VP years Jim uses bow shoot arrow over tree limb arrow tied light line used pull heavier line over limb shakes limb until model falls free may work cases treed mo dels think its lot safer blowing off limb bullet fired high-power rifle still have May 1989 issue Model Aviation will find article Joe Wagner make grabber retrieving mod els trees under 30 feet high Easy Way Out Trees grabber made electrical conduit features fork similar pitchfork its end grabbing model Joe Wagners model trapped 70ft-tall hickory called professional tree sur geon strongly recommend method George Wilson AMA District frequency coor dinator Warren Boudrie Pittaford NY Warrens letter described recent incident TR-260 made beautiful landing top 50-ft tree looked yellow pages under Tree Service located professional tree man responded within two hours Using appropriate climbing gear professional scaled tree lowered model ground damage small tear covering material cost recovery $35well worth opinion George Wilson noted should never re trieve model chopping down tree could dangerous both tree chopper model Its also likely illegal area Continued page 140 18 Model Aviation BILL WINTERS RIC SPECIAL Bills latest design offers rock steady stability solid realistic flight performance Special design concept originated 1947 publicity Mechanics Illustrated 1948 over years has evolved optimized flyer new specially designed semi-symmetrical airfoil contributes smoothness response behavior aspects its air worthiness Special fully aerobatic yet offers broad spectrum performance speeds Optional flaps 4-5 channel radio 45-50 twocycle 46-60 four cycle 40-60 electric 61 span 642 sq area 5-6 lbs flying weight Diamond airfoil stabilizer FEATURES Tempered aluminum landing gear ABS molded cowl hardware package full size rolled plans photo illustrated step-by-step instructions windshield window material accurately machine die cut selected balsa spruce plywood flexible steel cable V ailleron control IPAVEY675 TOWER LANE YSTEMS WEST CHESTER PA 19380 4 oRPoRATIoN 215-430-8645 words went lean has used least understood phrases modeling today seems time model motor loses power accusation went lean several reasons motor could slow down possibly quit properly broken-in model motor running right fuel plug properly cooled does sag heat up fuel level dropped too far needle tweaked too fan What should happen motor just slows very slightly quits firing cases motor sags down cooks three probable causes crankshaft bearings getting enough cooling fuel heat up start dragging 2 cylinder piston dont have enough clearance start binding 3 usual cause motor starts pre-igniting motor leaned makes power also makes heat makes heat plug element gets hotter ignition starts occurring soonen motor has little extra heat added because being new creating friction because weather hot because thefuel has too much nitro because glow plug retains too much heat motor can come up critical point ignition starts too soon over-advanced ignition combustion pressure presses piston down part up stroke turn generates morefriction heat again further aggravates pre-ignition problem Most model motors set up will run very close pre-ignition point because way get power Once motor goes over power peak way get back throttle back cool off Remember start lean motor get maximum power motor warms up seems slow down suffering pre-ignition slight bit pre-ignition dead lean setting may too bad because way usually get power out motor However much sagging dead lean setting giving away too much rich lean tolerance motor something should done Switching cooler running plug helps Reducing nitro fuel can make lot difference Adding little oil fuel can help some put together reasonable quantities isnt enough reducing compression ratio orden Unfortunately see lot cases pre ignition days reasons nitro expensive afrw years back people thinking nitro means power will order expensive fuel bad idea carry around can FAI type fuel 4 parts straight alcohol part straight castor next time ofyourflying buddies experiences leaning out tendency try cutting yourfuel FAI mixture see doesnt help ofyou may have experienced thrill offlying Fox motor would like no risk make offer will loan either Fox 40 Standard Eagle 60 choice Fly own airplane After 30 days return motor us pay UPS charges back would want Visa MasterCard number would charge motor returned Cant beat deal like can Happy flying anufacturing Company 5305 Towson Avenue FOX Fort Smith AR 72901 Phone 501 6461656 Safety/Preston Continued page 18 CyA glue eye letter Mark Miller El Segundo CA related painful conse quences getting drop cyanoacrylate CyA glue eye Mark gluing split piece balsawood two sides split sud denly snapped together ejected droplet glue landed cornea immediately cured emergency room nice mans gave him local anesthetic muscle relaxant could open eye again Ive previously mentioned incidents similar Marks can painful experience Ive never heard lasting injury Mark added incident drew atten tion interesting flaw medical coverage thats another story Im assuming shell out some bucks hospital visit Accidents can injure financially too Thats something dont always think about till hap pens Clarification letter Clair Sieverling pointed out original author tongue-in-cheek segment December 1990 Safety column called History Balsa Wood Model Aviation Clair Phoenix AZ wrote am original author piece non sense wrote editor Arizona Model Pilots Society AMPS newslet ter Prop Nut printed September 1985 issue thereof Thank Clair set ting record straight Have another safe month Flying Fun/Mathews Continued page 20 some other recreational activity others like have plugging away hobby years Bill thought moment Ive never learned NEW STARHAWK BIPLANE NEW MISS STARHAWK POSTER See your Starhawk Dealer details write Thorpe Engineering Corporation 1715 E Fairfield Mesa AZ 85203 Poster $500 P&H Prepaid riginal EZ UP Sun Shelters a8x 8 * Sturdy Steel Frames Heavy Duty Fade Resistant Nylon 1OX1OCanopies RedWhlte Blue alOx 15Sets Up less 60 Seconds Authorized -Z UP Corp DealerNo Rope Nothing Assemble John Peck Leisure Products Ltd *IMAA 3287 AMA 8580131 Ravenwood Road Other Sizes Colors Versailles KY 40383 Accessories Avallsble Plu •Custom Logos LetteringWrite1606 873-5172 140 Model Aviation CHECK EM BOTH OUT
Edition: Model Aviation - 1991/02
Page Numbers: 10, 14, 18, 140
John Preston Fiafety25 Comes First Peppertree Lu Sliver Spring MD 20906 II Watch compressed air/CO2 motors Ever have control stick come out hand re-treeving model airplanes COMPRESSED air/CO2 motors An interesting letter John Worth arrived last month described personal accident fortunately Out injury occurred experiment ing compressed air/CO2 motors Johns own words heres what happened have experimenting CO2 carbon dioxide motors couple years also past couple months compressed air mo tors Along way have combined technol ogies some interesting results Typical compressed air motors use initial pres sures 100 150 psi pounds per square inch Typical CO2 motors use perhaps 800 1000 psi Compressed air motors now commonly using plastic soda soft drink bottles anywhere three liters volume can appar ently handle up 175 200 psi pressure before bursting CO2 bottles actually better referred tanks made metal should able withstand pressures 3000 4000 psi before bursting What have doing using both air bottle CO2 tank model run mo tor Heres Pressurize air bottle about 120 psi air pressurize tank about 800 psi CO2 Between two have what effect needle valve normally prevents CO2 going air bottleuntil ready flight both systems charged normal pres sures start motorone flick prop does itusing air system motor runs rpm typically 3000 4000 rpm pro portional pressure use needle valve bleed CO2 air system re plenish air hold rpm essentially con stant small volume high pressure CO2 expands tremendously bleeds air bot tle typically triples length motor run suitable rpm over possible air alone So far good motor acts pressure regulator sorts varying its rpm according pressure going have getting ex cellent bench runs several months Free Flight Nats October ready some demonstrating flying other modelers see bunch us gathered gether prepared show what have ing seemed order filled air bot tle ran motor air alone No problem refilled air bottle started fill CO2 tank What didnt know should have needle valve between air CO2 systems fully closed As CO2 passed charging tank 5-lb fire extinguisher several us noticed snow flakes entering air bottle before dawned us what happening plastic bot tle exploded like cannon going off like cherry bomb Pieces model air bottle blew everywhere holding air bottle model next chest time ex plosion Several people within two three feet amazing nobody hurt al though felt like hit chest sledgehammer So model destroyed numb noise shock surprise Other wise nothing else amiss could have disaster Somebody particularly myself could have badly hurt think because air bottle probably blew something less 200 psi pressure force dispersed quickly plastic bottle broken up small pieces went very far So lucked out obviously matter needs further attention prevent anything like happening again first steps Pro vide interlock valve must fully closed before CO2 can put sys tem Also put pressure relief valve air system originally reliableobviously better needed Until minimal steps taken care am adding CO2 system Meanwhile anyone else might inclined try what have doing cautioned alert about what can happen unless adequate safety proce dures followed still think combining systems good idea motor performance standpoint has done safely Ill working problem will advise Im satisfied danger has controlled Readers might interested knowing reason soft drink manufacturers switched glass plastic containers larger Continued page 14 10 Model Aviation column provided address Items conceni regarding safety aspects model aviation activities Content column however opinion author does necessarily represent offidal posidon Academy Model Aeronautics 1 01-1 GOOD THE LEADER IN COMPETITION PROPELLERS NEW A CYCLE ES 100 THP DESIGN TAILORED HELICAL PITCH DEVELOPED TO GIVE MAXIMUM THRUST AT 4 CYCLE ENGINE RPM ALL THE LATEST TECHNIQUES USED ON OUR PRO SERIES 3 SEE BELOW DIA PITCH THP 1266778 136778 146778 1567 16678 NEW PRO SERIES 3 NEW HIGH TECH AIRFOIL SECTION 10T020% INCREASE IN THRUST MPG OF SELECT HARD MAPLE WOOD WILL NOT FATIGUE LIKE SYNTHETICS FUEL PROOF HIGH LUSTER FINISH DIAPITCH 5/a34 634 72633456 833/a4566 845667 9456677/s 1045667 106W6W 106EW 114677778 115W 116EW 1167 124W 125W 1256 1356 1456 1556 164N 16678 sizes liter up serious injuries caused glass bottles exploding Apparently some incidents occurred bottles sitting shelves supermarket Canadian government has mandatory reg ulation prohibiting large-size glass containers carbonated soft drinks wasnt necessary US because soft drink manufacturers made switch plastic bottles voluntarily Lit tle did know would also benefit com pressed air modelers old glass containers werent light enough use model they would also have ac cident waiting happen comment Johns experience hybrid air/CO2 system believe pres sure relief valve must model crash shortly after takeoff crash pre vented prop turning wouldnt take long CO2 build up sufficient pressure air bottle instantly destroy model Transmitter control stick failure Sandy Schmidt Brunswick ME unique experi ence flying friends model Over Sandy Several weeks ago fellow club member continuing testing prototype cabin biplane gorgeous well-built model flies sedately 29 diesel Al total about 30 flights model three particular day pits mentioned thought time see well would accomplish simple aerobatics Al asked fly plane through sedate sequence loops rollsperhaps plane pilot liked try spin Both us re checked control sensitivity range CG general airworthiness Al started diesel again checked throttle elevator rudder con trols taxi its tricycle gear perfect takeoff arrow-straight initial turns pat tern altitude disclosed no out-of-trim conditions Larger rectangular patterns showed no glitches introduction felt very comfortable new plane planned first loop roll ascertain control authority overlean out-of-trim conditions loop beautiful hesitation commenced roll maneuver completed just fine model returned back straight level just started turn back down wind another pass transmitter control stick came out hand bipe reason ably steady quickly making time away field yelled Al rudder/elevator con trol stick fell out ground After Id screamed second time got message started looking stick About time throttled back left en gine control stick jammed right thumb down right gimbal found some slight control plane made se ries sweeping S-turns back wind headed back toward field tried put control stick back gimbal Al said plastic broken Al suggested rather attempt run way landing might endanger spectators fellow pilots should gently crash land model out boonies seemed like great idea pulled throttle way back tried keep wings level let biplane settle two-foot-tall grass shrubs clay amazement other broken con trol stick discernible damage bro ken prop Al took apart transmitter epox ied stick back place model has since Continued page 18 PLANE TRACKER PILOT GLASSES Blocks 100% harmful UV rays High impact polycarbonate extra protect ion Dual gradient lens [Mirror Grayj Fit over prescription glasses Hard coated scratch resistance 1 year limited warranty Case included AVAILABLE IN Clear $1795 Amber $1995 Gray $1995 Mirror Gray $2495 CA Mask Paint Mask Banded Ear Plugs $1695 $2295 $795 {kBJl PLU5 See hobby dealer first doesni have what need order direct SAFETY PLUS P 0 Box 1173 Dept iM Clinton MS 39060 1-800-842-7233 Cant US 601924-9040 Satislaclion guaranteed Shipping handling included Add~for COD VISA1MC Only certified checks money orders accepted Minimum order S 12X Itiree packages ot4 Pomerpoles t250 per package $150 shipping handling CT residents add 75% salet tan Prices ouhiact change wiThout notice DEALER INDUINUS INVITED further ntcrmalrsr dealer prices send SASS Business Card SERMO R/C SNAP CONNECTORS Inc Cedar Corners Station Box 16787 Stamford CT 06905 1203322-6294 14 Model Aviation Wraparound style eliminates glare angles / RC PYLON RACING SERIES 500 DIA PITCH 7SN 5/aN 86/a778 SERIES 400C 8 66t/a77Vu7/a 9777 W WIDE BLADE EW EXTRA WIDE N NARROW very successfully flown several days have flying RC since 1958 have share battery radio motor prop fuel failures case reversed controls transmitter switch short reversed aile rons Aeromaster never did foresee transmitter stick falling out hand Ironically Sandys letter arrived mail same day experienced control failure problem parking brake release handle 1988 Taurus came out hand due ca ble breakage happened leaving work dark rainy night fortunate released parking brake before cable snapped others might have same experi ence fairly easy daylight see piece parking brake mechanism cable taches can reach down under dash board trip hand installing re placement cable $675 proved another mat ter Cars designed easily repaired Planes trees December 1990 Safety col umn mentioned modeler fell death attempting retrieve model tree asked readers better methods re trieving treed models climbing tree received some diverse suggestions noveland perhaps dangerous method came Bill Lang Chester IL Bill reports 100 percent success five model retrie vals very little damage planes shot off limbs tree model stranded says must use highvelocity rifle ensure bullet shatters passes through tree limb Slow bullets wont tend go off uncontrolled direc tions Maybe works Bill cant recom mend area miss tree limb bullet could threaten human life safer method came well-known Free Flighter Jim Scarborough served AMA Dis trict X VP years Jim uses bow shoot arrow over tree limb arrow tied light line used pull heavier line over limb shakes limb until model falls free may work cases treed mo dels think its lot safer blowing off limb bullet fired high-power rifle still have May 1989 issue Model Aviation will find article Joe Wagner make grabber retrieving mod els trees under 30 feet high Easy Way Out Trees grabber made electrical conduit features fork similar pitchfork its end grabbing model Joe Wagners model trapped 70ft-tall hickory called professional tree sur geon strongly recommend method George Wilson AMA District frequency coor dinator Warren Boudrie Pittaford NY Warrens letter described recent incident TR-260 made beautiful landing top 50-ft tree looked yellow pages under Tree Service located professional tree man responded within two hours Using appropriate climbing gear professional scaled tree lowered model ground damage small tear covering material cost recovery $35well worth opinion George Wilson noted should never re trieve model chopping down tree could dangerous both tree chopper model Its also likely illegal area Continued page 140 18 Model Aviation BILL WINTERS RIC SPECIAL Bills latest design offers rock steady stability solid realistic flight performance Special design concept originated 1947 publicity Mechanics Illustrated 1948 over years has evolved optimized flyer new specially designed semi-symmetrical airfoil contributes smoothness response behavior aspects its air worthiness Special fully aerobatic yet offers broad spectrum performance speeds Optional flaps 4-5 channel radio 45-50 twocycle 46-60 four cycle 40-60 electric 61 span 642 sq area 5-6 lbs flying weight Diamond airfoil stabilizer FEATURES Tempered aluminum landing gear ABS molded cowl hardware package full size rolled plans photo illustrated step-by-step instructions windshield window material accurately machine die cut selected balsa spruce plywood flexible steel cable V ailleron control IPAVEY675 TOWER LANE YSTEMS WEST CHESTER PA 19380 4 oRPoRATIoN 215-430-8645 words went lean has used least understood phrases modeling today seems time model motor loses power accusation went lean several reasons motor could slow down possibly quit properly broken-in model motor running right fuel plug properly cooled does sag heat up fuel level dropped too far needle tweaked too fan What should happen motor just slows very slightly quits firing cases motor sags down cooks three probable causes crankshaft bearings getting enough cooling fuel heat up start dragging 2 cylinder piston dont have enough clearance start binding 3 usual cause motor starts pre-igniting motor leaned makes power also makes heat makes heat plug element gets hotter ignition starts occurring soonen motor has little extra heat added because being new creating friction because weather hot because thefuel has too much nitro because glow plug retains too much heat motor can come up critical point ignition starts too soon over-advanced ignition combustion pressure presses piston down part up stroke turn generates morefriction heat again further aggravates pre-ignition problem Most model motors set up will run very close pre-ignition point because way get power Once motor goes over power peak way get back throttle back cool off Remember start lean motor get maximum power motor warms up seems slow down suffering pre-ignition slight bit pre-ignition dead lean setting may too bad because way usually get power out motor However much sagging dead lean setting giving away too much rich lean tolerance motor something should done Switching cooler running plug helps Reducing nitro fuel can make lot difference Adding little oil fuel can help some put together reasonable quantities isnt enough reducing compression ratio orden Unfortunately see lot cases pre ignition days reasons nitro expensive afrw years back people thinking nitro means power will order expensive fuel bad idea carry around can FAI type fuel 4 parts straight alcohol part straight castor next time ofyourflying buddies experiences leaning out tendency try cutting yourfuel FAI mixture see doesnt help ofyou may have experienced thrill offlying Fox motor would like no risk make offer will loan either Fox 40 Standard Eagle 60 choice Fly own airplane After 30 days return motor us pay UPS charges back would want Visa MasterCard number would charge motor returned Cant beat deal like can Happy flying anufacturing Company 5305 Towson Avenue FOX Fort Smith AR 72901 Phone 501 6461656 Safety/Preston Continued page 18 CyA glue eye letter Mark Miller El Segundo CA related painful conse quences getting drop cyanoacrylate CyA glue eye Mark gluing split piece balsawood two sides split sud denly snapped together ejected droplet glue landed cornea immediately cured emergency room nice mans gave him local anesthetic muscle relaxant could open eye again Ive previously mentioned incidents similar Marks can painful experience Ive never heard lasting injury Mark added incident drew atten tion interesting flaw medical coverage thats another story Im assuming shell out some bucks hospital visit Accidents can injure financially too Thats something dont always think about till hap pens Clarification letter Clair Sieverling pointed out original author tongue-in-cheek segment December 1990 Safety column called History Balsa Wood Model Aviation Clair Phoenix AZ wrote am original author piece non sense wrote editor Arizona Model Pilots Society AMPS newslet ter Prop Nut printed September 1985 issue thereof Thank Clair set ting record straight Have another safe month Flying Fun/Mathews Continued page 20 some other recreational activity others like have plugging away hobby years Bill thought moment Ive never learned NEW STARHAWK BIPLANE NEW MISS STARHAWK POSTER See your Starhawk Dealer details write Thorpe Engineering Corporation 1715 E Fairfield Mesa AZ 85203 Poster $500 P&H Prepaid riginal EZ UP Sun Shelters a8x 8 * Sturdy Steel Frames Heavy Duty Fade Resistant Nylon 1OX1OCanopies RedWhlte Blue alOx 15Sets Up less 60 Seconds Authorized -Z UP Corp DealerNo Rope Nothing Assemble John Peck Leisure Products Ltd *IMAA 3287 AMA 8580131 Ravenwood Road Other Sizes Colors Versailles KY 40383 Accessories Avallsble Plu •Custom Logos LetteringWrite1606 873-5172 140 Model Aviation CHECK EM BOTH OUT
