Radio Control Electrics Bob Kopski BEFORE get some Electric techni cal goodies lets take look some photos Ive received inputs came recent weeks significant its own special way First Brian Bailie Robbinsville NJ original glider design big differenceits solar-powered Now weve heard solar-powered accom plishinents before prob ably ones high-tech big-dol lar backing Brian 16-year-old high school student plane got him first Greater Trenton Science Fair What Im wondering what plane gonna get him Up Last Down event 1984 Electric Fly Brian attended last years meet telling about plans project time model incorporates 17% computer-designed wing section weighs 59 oz loading 75 oz/sq ft Astro 05 Cobalt motor gets its power 36 solar cells wing According Brian solar cells de velop about 36 watts direct sunlight Using Rule Thumb MA April 1984 Power Cruise Watts ht lbs x Wing Loading oz/sq ft case Watts 75 ince 36 28 sure sounds like should fly Brian says does part 59 oz on-board battery pack interpret temporary backup such case flight will improve signif icantly believe Brian didnt say plane name Anyway congratula tions Brian looking forward seeing accomplishment operation Next Dr John Mountjoy Win ston-Salem NC have own pre scription lots rest relaxation impressive fleet kinds Elec trics built over past year-and-a-half make beautiful pic ture So take heart still working first Electricfor doctor reports fly beautifully plane foreground Wasp seven cells cobalt 05 7 x 4 prop Ive seen several Waspsvery im pressive acrobatic craft As understand it will soon kitted Leisure Hurry up Roland glider Electricus also using cobalt 05 7 x 4 seven 800 mAh cells Playboy gets its go six 12 Ah cells powering Leisure 251 gear system Leisure 361 turns Robbe prop Jomar SC-I Speed Control metering out juice seven cells keep Hying Quaker airborne Finally Train-Air 20 pulled cobalt 15 Jomar SC-l between motor 12 cells good Doctor didnt give weights but Playboy covered Micafilin very light material sounds like Doctor John knows important watch Electric weight sure would nice 54 MnrII Aviation 10 well Electrics batteries hold up Bob compared two packs 300 flights other brand-new Both 6-cell Sanyo 12 Ah packs charged con stant current 40 amps lab supply discharged constant 10 amps another pIece equipmsnL Battery voltage measured dIrectly pack terminals fleet Electrics belongs Dr John Mountloy WInston-Salem Ne wnat hying 5151 looks quiet Note thst three planes use Trexier airwheeishelps keep pisnes light Doe must quite pIlot go hot Pattern ship like twin-tailed Wasp lazy-days Old-Timer like Playboyor Saliplanel see Electric Fly thanks both gentlemen sharing photos us really showin us big Electric way Another battery story lot Elec tric flying always take least two planes field Having plane allows charge fly its possible have plane air time Because usually fly flight right after other use conservative safe charge technique previously described MA December 1983 Basically charge technique puts known charge current x time empty battery total amount charge safely below label capacity battery other words dont try fill tank theres much point since can fly nearly continuously anyway means virtually never digital charge approach does put much battery can hold takes longer accomplish dont like standing around waiting pack voltage peakId rather fly set desired current start 15-minute timer go fly something else time switch doing its thing lead-in brings main part story Over past two years Ive accumulated over 300 flights means charges discharges too original Spectra flying done same batteryand its still going strong have taken position battery should last hundreds flights MA December 1983 April 1984 given proper care Since charge technique Ive described never pushes since battery way never pressed limit made heat probably vent during charging consider example proper care just what has happened battery con dition throughout use can give partial answer decided test battery com parison another new neverContinued page 159 THE OLYMPIC V Ace RIC now offers American made alternative plastic imports Olympic V Time proven quality dependability sensible solid package tradition Silver Seven results unit perfect first time R/Cer sport flier So modeler can choose size type price range servo requires Olympic V furnished less servos Any modern positive pulse servos Ace other brand will work system connectors furnished So now alternative Ace Silver Seven performance import price Available approved 50 53 72 mHz channels RECEIVER Proven Silver Seven Design Wired five channels Gold plated Deans connectors 3/4 x 1-11/32 x 2-1/4 14 oz 500 ma Rechargeable Nicds Dual Charger furnished Servo connectors furnished 20G500Olympic V System Assembled $14995 TRANSMITTER Four channels standard fifth channel optional Proven Silver Seven hi output RF deck Open Gimbal Sticks Rugged vinyl clad aluminum case Expended scale voltmeter monitor battery Rechargeable Ni-cd equipped 96V @ 500 ma Offset antenna maximum radiation Send $200 complete catalog Ace items available dealer order direct add $100 handling fee [ACE I/C Em P0 Box 511E Higginsville Mo 64037 816 584-7121 ntmber1QA orIgInaI-aealgn solar-cell-powered Iectrlc Sailplane won 1954 Greater Trenton Science Fair 1 6-year-old Brian Billie Robbinavllie NJ cobalt 05 motor gate up 36 watts power direct sunlight 36 solar cells wing Bob eays isa possibility Brian will fly model years Electric Fly Model Magic Filler Quick setting Light weigbt Nnn Fillets Gap filling Ding repair U See dealer first write call $595 Retail 8 fI oz Model Magic Products Model Magic Products PO Box 7784 St Paul Minn 55119 715 425-1397 Adhesion Balsa Foam Fiberglass Strength Flexing Spreading Fuel Resistance Sanding Hardness Finishing Shelf Ufe Tint Acceptance Water Resistance Comparison Chart Model Magic Exceent Product X Very Poor Good As medium balsa As Hard Balsa Any finish/covering till used up Excellent Soft balsa Soft balsa Spoils 57 mo Very Poor Test methods arid data avalable request care enough fill very best sist Model Magic Filer Circus Magic Filler veloping composite structures Burt Rutan has certainly leaders Proud Youd darn well better believe should too Dee B Mathews 506 South Walnut Greensburg KS 67054 RC ElectricslKopski Continued page 55 used battery Both six-cell 12 Ah Sanyo packs chance just happened run testing time 300 flights previously recorded Un fortunately have break-in data used pack new cant certain flying has af fected battery So purposes experiment made assumption used battery new like new included test Such assumption allows determine much used pack has degraded usesort test consisted six charge/dis charge cycles pack pack carefully charged using regulated lab supply specific time periods shown table charge current used constant 40 amps charge time varied purposes test times varied rela tively short pushing-it long Following charges described pack carefully discharged using electronically-regulated current sink like reverse supply effect packs loaded electronic load such constant discharge current 100 amps flowed batteries under test no matter what terminal voltage discharges carefully timed beginning cutoff purposes test chose cutoff equivalent volt per cell six volts total six-cell packs battery pack voltage dropped value during discharge watch stopped No attempt made deter six cells accounted depressed terminal voltage As turns out much-used pack probably has some noticeable cell imbalance appears some cells did drop deeper rapidly others same pack preceding description clear can tell what percentage charge battery returns Also quite same can tell what Iie] ] d $100 Cash Check Stamps 32 Page Tabloid size illustrated DISCOUNT Catalog Sent 1st Class Mail COMET COX FLYLINE FOX GOLDBERG GUILLOWS JETCO K&3- PACTRA PECK POLYMER PERFECT SIG- STERLING SULLIVAN TOP FLITE & OTHERS PENN VALLEY HONEY CENTER 837 1 Main 3t Lanshli 1 19446 battery capacity battery known fully-charged total ampere-hours important another par ameter also importantthe battery-ter minal voltage battery has high ternal losses terminal voltage under load will depressed flight made way will good flight battery maintains high voltage out put motor Lets look table analyze re sults tests Looking new bat tery first see familiar phenomenon first flights good means its common experience first sometimes second flights day good followthe battery seems go through warm-up though dont think has anything temper ature Anyway first three fiveminute charges apparent charge return battery gradually improves reach level very close charge put other words get charge back performance continues creasingly longer charges up limits testeda sixth cycle input equal SeDtember 1984 159 1 AERONCAC3 GIANT SCALE 4CYcLE6O-90 SEND $200 FOR COMPLETE CATALOG OF FINE KITS IKON NW5T PO Box 566 Auburn WA 98071 206 941-8248 New Model Magic Products Model Magic Epoxy Plus 2 Part 8 Mm Use anywhere two part epoxy used Light weight Sandable Carveable Excellent Gap Filling Non Sagging Superior Strength Sands and carves like basswood! 6 fI oz $895 See dealer first write cal Madel Magic Products Inc ,.P0 Box 19784 St Paul MN 55119 715425-1397 Converting Gb En gines Ignition has advantages such Savings cost fuel Less oily mess no Plugs burn out Use boats Cars Planes helicopters Can adapted Larger engines place Flywheel Thus saving weight No machine work voiced needed screw driver drill Most available Gb en gines can converted features yours won new rn iI6IJ5IL MAKK LDlTwo four cycles pointless sstens no points worry aboutTwins etc unit comes predrilled disk sensor formed clamp mounting sensor engine Complete instructions convertion timing procedures in- Complete cluded Unit operates 48 v Low current drain Weight 2 ozs size 2 x 2 x 75 System inches needed complete system Ignition coil spark plug on/off switch available separately complete system fuel 69 95 ignition lines included No ba e es nc uded State engine size use ordering FABTRONICSCash M 0 Certified Check plus $300 postage handling 15860 Via Riverapersonal checks take time clear Calif residents add tax San Lorenzo CA 94580 Brochure $1 00 refundable purchase label capacity 72 ampere-minutes 12 Ah behavior ter minal voltage during charge think battery could actually hold charge voltage did rise usual values experienced during digital charge Now much-used battery Notice second test cycle brings right up about best can warmed up faster brand-new pack Con tinuing testing now see some funnies fourth cycle results say battery delivered put course cant believe l06o output result some cell imbalance ie some cells probably 4 x 10 ampere-minutes result previous cycle cutoffs being determined some weaker cellsthe better ones did get sufficiently discharged battery empty recharged Anyway numbers may some what error basic message good cared-for batteries can facili tate lot top-quality flying As now move up fifth cycle something different seems taking place apparent charge return per centage seems decreasing substanti ally Notice also end-of-charge terminal voltage rather highmaybe past peak though battery likely certain its cells fully charged sixth run tends confirm suspicion attempt put charge battery produces same discharge ampere-minutes fifth run corresponding lower output/input percen tage venting well Good griefone precious cells actually vented Oh well anything science No isnt first time Ive popped sorta knew gonna happen fact quite warm overcharged pack quickly cooled put back use out suffering much far can see preceding test data evi dent can expect recover nearly battery charge within limits both new well-used well-caredPIANUT SCALS MODELS Kits $595 ZEROMILES M-IB PIETENPOLDRUINE PIPER CUBCOUGAR ANDRESONGIPSY MOTH MUSTANGLACEY M-IOGANAGOBIE jjjjrjWstmd PRAIRIE BIRD 4 KIT $595 SPORT MODELS BABY ACE $649 ONE NITE 28 ONE NIlE Ic 9595 STRINGLESS $495 PECK ROG RADIO 3 LIMPS CONTROLLED Ii and 13 FOOT LONOKITS OR READY TO FLY NOW IN TNREE COLORS ORANGE YELLOW LOW PRICES CATAIX No 25 $150 Pck-Pelyauers PN~l9 4424638 469-8615 L BOX 2498 MA LA MESA CA 92041 batteries Also assuming used originally just like new apparent battery capacity decreases use case looks like about / original capacity remain ing bad considering 300 flights Surely battery does owe anything its still usable Taking look terminal voltage during discharge last cycles both batteries see terminal voltage heavily-used pack notice ably lower new pack little voltage can make big difference mo tor power Im sure plane would show pep longer period new battery However Ive decided leave pack place perhaps rerun tests after another hundred flights just see what happens point rest case properly cared-for batteries can last hundreds flights Please note Im saying same wouldnt true batteries have digitally charged hundreds timesthe fact simply dont have therefore cant tell question whether lessthan-maximum charging good Ill simply redirect attention April 1984 issue page 42 flight histograms plane very bat tery tested show hundreds data points averaging out about 13-minute flight times Period Happy Landings Bob Kopski 25 West End Dr Lans dale PA 19446 RC HelicopterslJolly Continued page 56 sensitive rotor blade Normal blade construction calls hardwood leading edge balsa trailing edge use hardwood important two reasons first gives necessary blade attach ment point second attempts balance rotor blade closer pivoting axis Rotor blades airfoil has its center gravity too far aft pivot point likely flutter commonly seen all-flying tailplanes used RC sailplanes rotor blades too werent Hiller flybar-and-paddle system transmitting necessary aerodynamic dampening rotor system machines would quite unflyable out going too far aerodynam ically speaking flybarless Bell-inputonly system used Horizon Kobe Kiko R-22 must have center-ofgravity-corrected rotor blades perform properly Without flybar aft center gravity first control input would send blade oscillation might never come back equilibrium oscillation would course negate control inputs rotor system Helicopters flybars fly 160 Model Aviation
Edition: Model Aviation - 1984/09
Page Numbers: 54, 55, 159, 160
Radio Control Electrics Bob Kopski BEFORE get some Electric techni cal goodies lets take look some photos Ive received inputs came recent weeks significant its own special way First Brian Bailie Robbinsville NJ original glider design big differenceits solar-powered Now weve heard solar-powered accom plishinents before prob ably ones high-tech big-dol lar backing Brian 16-year-old high school student plane got him first Greater Trenton Science Fair What Im wondering what plane gonna get him Up Last Down event 1984 Electric Fly Brian attended last years meet telling about plans project time model incorporates 17% computer-designed wing section weighs 59 oz loading 75 oz/sq ft Astro 05 Cobalt motor gets its power 36 solar cells wing According Brian solar cells de velop about 36 watts direct sunlight Using Rule Thumb MA April 1984 Power Cruise Watts ht lbs x Wing Loading oz/sq ft case Watts 75 ince 36 28 sure sounds like should fly Brian says does part 59 oz on-board battery pack interpret temporary backup such case flight will improve signif icantly believe Brian didnt say plane name Anyway congratula tions Brian looking forward seeing accomplishment operation Next Dr John Mountjoy Win ston-Salem NC have own pre scription lots rest relaxation impressive fleet kinds Elec trics built over past year-and-a-half make beautiful pic ture So take heart still working first Electricfor doctor reports fly beautifully plane foreground Wasp seven cells cobalt 05 7 x 4 prop Ive seen several Waspsvery im pressive acrobatic craft As understand it will soon kitted Leisure Hurry up Roland glider Electricus also using cobalt 05 7 x 4 seven 800 mAh cells Playboy gets its go six 12 Ah cells powering Leisure 251 gear system Leisure 361 turns Robbe prop Jomar SC-I Speed Control metering out juice seven cells keep Hying Quaker airborne Finally Train-Air 20 pulled cobalt 15 Jomar SC-l between motor 12 cells good Doctor didnt give weights but Playboy covered Micafilin very light material sounds like Doctor John knows important watch Electric weight sure would nice 54 MnrII Aviation 10 well Electrics batteries hold up Bob compared two packs 300 flights other brand-new Both 6-cell Sanyo 12 Ah packs charged con stant current 40 amps lab supply discharged constant 10 amps another pIece equipmsnL Battery voltage measured dIrectly pack terminals fleet Electrics belongs Dr John Mountloy WInston-Salem Ne wnat hying 5151 looks quiet Note thst three planes use Trexier airwheeishelps keep pisnes light Doe must quite pIlot go hot Pattern ship like twin-tailed Wasp lazy-days Old-Timer like Playboyor Saliplanel see Electric Fly thanks both gentlemen sharing photos us really showin us big Electric way Another battery story lot Elec tric flying always take least two planes field Having plane allows charge fly its possible have plane air time Because usually fly flight right after other use conservative safe charge technique previously described MA December 1983 Basically charge technique puts known charge current x time empty battery total amount charge safely below label capacity battery other words dont try fill tank theres much point since can fly nearly continuously anyway means virtually never digital charge approach does put much battery can hold takes longer accomplish dont like standing around waiting pack voltage peakId rather fly set desired current start 15-minute timer go fly something else time switch doing its thing lead-in brings main part story Over past two years Ive accumulated over 300 flights means charges discharges too original Spectra flying done same batteryand its still going strong have taken position battery should last hundreds flights MA December 1983 April 1984 given proper care Since charge technique Ive described never pushes since battery way never pressed limit made heat probably vent during charging consider example proper care just what has happened battery con dition throughout use can give partial answer decided test battery com parison another new neverContinued page 159 THE OLYMPIC V Ace RIC now offers American made alternative plastic imports Olympic V Time proven quality dependability sensible solid package tradition Silver Seven results unit perfect first time R/Cer sport flier So modeler can choose size type price range servo requires Olympic V furnished less servos Any modern positive pulse servos Ace other brand will work system connectors furnished So now alternative Ace Silver Seven performance import price Available approved 50 53 72 mHz channels RECEIVER Proven Silver Seven Design Wired five channels Gold plated Deans connectors 3/4 x 1-11/32 x 2-1/4 14 oz 500 ma Rechargeable Nicds Dual Charger furnished Servo connectors furnished 20G500Olympic V System Assembled $14995 TRANSMITTER Four channels standard fifth channel optional Proven Silver Seven hi output RF deck Open Gimbal Sticks Rugged vinyl clad aluminum case Expended scale voltmeter monitor battery Rechargeable Ni-cd equipped 96V @ 500 ma Offset antenna maximum radiation Send $200 complete catalog Ace items available dealer order direct add $100 handling fee [ACE I/C Em P0 Box 511E Higginsville Mo 64037 816 584-7121 ntmber1QA orIgInaI-aealgn solar-cell-powered Iectrlc Sailplane won 1954 Greater Trenton Science Fair 1 6-year-old Brian Billie Robbinavllie NJ cobalt 05 motor gate up 36 watts power direct sunlight 36 solar cells wing Bob eays isa possibility Brian will fly model years Electric Fly Model Magic Filler Quick setting Light weigbt Nnn Fillets Gap filling Ding repair U See dealer first write call $595 Retail 8 fI oz Model Magic Products Model Magic Products PO Box 7784 St Paul Minn 55119 715 425-1397 Adhesion Balsa Foam Fiberglass Strength Flexing Spreading Fuel Resistance Sanding Hardness Finishing Shelf Ufe Tint Acceptance Water Resistance Comparison Chart Model Magic Exceent Product X Very Poor Good As medium balsa As Hard Balsa Any finish/covering till used up Excellent Soft balsa Soft balsa Spoils 57 mo Very Poor Test methods arid data avalable request care enough fill very best sist Model Magic Filer Circus Magic Filler veloping composite structures Burt Rutan has certainly leaders Proud Youd darn well better believe should too Dee B Mathews 506 South Walnut Greensburg KS 67054 RC ElectricslKopski Continued page 55 used battery Both six-cell 12 Ah Sanyo packs chance just happened run testing time 300 flights previously recorded Un fortunately have break-in data used pack new cant certain flying has af fected battery So purposes experiment made assumption used battery new like new included test Such assumption allows determine much used pack has degraded usesort test consisted six charge/dis charge cycles pack pack carefully charged using regulated lab supply specific time periods shown table charge current used constant 40 amps charge time varied purposes test times varied rela tively short pushing-it long Following charges described pack carefully discharged using electronically-regulated current sink like reverse supply effect packs loaded electronic load such constant discharge current 100 amps flowed batteries under test no matter what terminal voltage discharges carefully timed beginning cutoff purposes test chose cutoff equivalent volt per cell six volts total six-cell packs battery pack voltage dropped value during discharge watch stopped No attempt made deter six cells accounted depressed terminal voltage As turns out much-used pack probably has some noticeable cell imbalance appears some cells did drop deeper rapidly others same pack preceding description clear can tell what percentage charge battery returns Also quite same can tell what Iie] ] d $100 Cash Check Stamps 32 Page Tabloid size illustrated DISCOUNT Catalog Sent 1st Class Mail COMET COX FLYLINE FOX GOLDBERG GUILLOWS JETCO K&3- PACTRA PECK POLYMER PERFECT SIG- STERLING SULLIVAN TOP FLITE & OTHERS PENN VALLEY HONEY CENTER 837 1 Main 3t Lanshli 1 19446 battery capacity battery known fully-charged total ampere-hours important another par ameter also importantthe battery-ter minal voltage battery has high ternal losses terminal voltage under load will depressed flight made way will good flight battery maintains high voltage out put motor Lets look table analyze re sults tests Looking new bat tery first see familiar phenomenon first flights good means its common experience first sometimes second flights day good followthe battery seems go through warm-up though dont think has anything temper ature Anyway first three fiveminute charges apparent charge return battery gradually improves reach level very close charge put other words get charge back performance continues creasingly longer charges up limits testeda sixth cycle input equal SeDtember 1984 159 1 AERONCAC3 GIANT SCALE 4CYcLE6O-90 SEND $200 FOR COMPLETE CATALOG OF FINE KITS IKON NW5T PO Box 566 Auburn WA 98071 206 941-8248 New Model Magic Products Model Magic Epoxy Plus 2 Part 8 Mm Use anywhere two part epoxy used Light weight Sandable Carveable Excellent Gap Filling Non Sagging Superior Strength Sands and carves like basswood! 6 fI oz $895 See dealer first write cal Madel Magic Products Inc ,.P0 Box 19784 St Paul MN 55119 715425-1397 Converting Gb En gines Ignition has advantages such Savings cost fuel Less oily mess no Plugs burn out Use boats Cars Planes helicopters Can adapted Larger engines place Flywheel Thus saving weight No machine work voiced needed screw driver drill Most available Gb en gines can converted features yours won new rn iI6IJ5IL MAKK LDlTwo four cycles pointless sstens no points worry aboutTwins etc unit comes predrilled disk sensor formed clamp mounting sensor engine Complete instructions convertion timing procedures in- Complete cluded Unit operates 48 v Low current drain Weight 2 ozs size 2 x 2 x 75 System inches needed complete system Ignition coil spark plug on/off switch available separately complete system fuel 69 95 ignition lines included No ba e es nc uded State engine size use ordering FABTRONICSCash M 0 Certified Check plus $300 postage handling 15860 Via Riverapersonal checks take time clear Calif residents add tax San Lorenzo CA 94580 Brochure $1 00 refundable purchase label capacity 72 ampere-minutes 12 Ah behavior ter minal voltage during charge think battery could actually hold charge voltage did rise usual values experienced during digital charge Now much-used battery Notice second test cycle brings right up about best can warmed up faster brand-new pack Con tinuing testing now see some funnies fourth cycle results say battery delivered put course cant believe l06o output result some cell imbalance ie some cells probably 4 x 10 ampere-minutes result previous cycle cutoffs being determined some weaker cellsthe better ones did get sufficiently discharged battery empty recharged Anyway numbers may some what error basic message good cared-for batteries can facili tate lot top-quality flying As now move up fifth cycle something different seems taking place apparent charge return per centage seems decreasing substanti ally Notice also end-of-charge terminal voltage rather highmaybe past peak though battery likely certain its cells fully charged sixth run tends confirm suspicion attempt put charge battery produces same discharge ampere-minutes fifth run corresponding lower output/input percen tage venting well Good griefone precious cells actually vented Oh well anything science No isnt first time Ive popped sorta knew gonna happen fact quite warm overcharged pack quickly cooled put back use out suffering much far can see preceding test data evi dent can expect recover nearly battery charge within limits both new well-used well-caredPIANUT SCALS MODELS Kits $595 ZEROMILES M-IB PIETENPOLDRUINE PIPER CUBCOUGAR ANDRESONGIPSY MOTH MUSTANGLACEY M-IOGANAGOBIE jjjjrjWstmd PRAIRIE BIRD 4 KIT $595 SPORT MODELS BABY ACE $649 ONE NITE 28 ONE NIlE Ic 9595 STRINGLESS $495 PECK ROG RADIO 3 LIMPS CONTROLLED Ii and 13 FOOT LONOKITS OR READY TO FLY NOW IN TNREE COLORS ORANGE YELLOW LOW PRICES CATAIX No 25 $150 Pck-Pelyauers PN~l9 4424638 469-8615 L BOX 2498 MA LA MESA CA 92041 batteries Also assuming used originally just like new apparent battery capacity decreases use case looks like about / original capacity remain ing bad considering 300 flights Surely battery does owe anything its still usable Taking look terminal voltage during discharge last cycles both batteries see terminal voltage heavily-used pack notice ably lower new pack little voltage can make big difference mo tor power Im sure plane would show pep longer period new battery However Ive decided leave pack place perhaps rerun tests after another hundred flights just see what happens point rest case properly cared-for batteries can last hundreds flights Please note Im saying same wouldnt true batteries have digitally charged hundreds timesthe fact simply dont have therefore cant tell question whether lessthan-maximum charging good Ill simply redirect attention April 1984 issue page 42 flight histograms plane very bat tery tested show hundreds data points averaging out about 13-minute flight times Period Happy Landings Bob Kopski 25 West End Dr Lans dale PA 19446 RC HelicopterslJolly Continued page 56 sensitive rotor blade Normal blade construction calls hardwood leading edge balsa trailing edge use hardwood important two reasons first gives necessary blade attach ment point second attempts balance rotor blade closer pivoting axis Rotor blades airfoil has its center gravity too far aft pivot point likely flutter commonly seen all-flying tailplanes used RC sailplanes rotor blades too werent Hiller flybar-and-paddle system transmitting necessary aerodynamic dampening rotor system machines would quite unflyable out going too far aerodynam ically speaking flybarless Bell-inputonly system used Horizon Kobe Kiko R-22 must have center-ofgravity-corrected rotor blades perform properly Without flybar aft center gravity first control input would send blade oscillation might never come back equilibrium oscillation would course negate control inputs rotor system Helicopters flybars fly 160 Model Aviation
Edition: Model Aviation - 1984/09
Page Numbers: 54, 55, 159, 160
Radio Control Electrics Bob Kopski BEFORE get some Electric techni cal goodies lets take look some photos Ive received inputs came recent weeks significant its own special way First Brian Bailie Robbinsville NJ original glider design big differenceits solar-powered Now weve heard solar-powered accom plishinents before prob ably ones high-tech big-dol lar backing Brian 16-year-old high school student plane got him first Greater Trenton Science Fair What Im wondering what plane gonna get him Up Last Down event 1984 Electric Fly Brian attended last years meet telling about plans project time model incorporates 17% computer-designed wing section weighs 59 oz loading 75 oz/sq ft Astro 05 Cobalt motor gets its power 36 solar cells wing According Brian solar cells de velop about 36 watts direct sunlight Using Rule Thumb MA April 1984 Power Cruise Watts ht lbs x Wing Loading oz/sq ft case Watts 75 ince 36 28 sure sounds like should fly Brian says does part 59 oz on-board battery pack interpret temporary backup such case flight will improve signif icantly believe Brian didnt say plane name Anyway congratula tions Brian looking forward seeing accomplishment operation Next Dr John Mountjoy Win ston-Salem NC have own pre scription lots rest relaxation impressive fleet kinds Elec trics built over past year-and-a-half make beautiful pic ture So take heart still working first Electricfor doctor reports fly beautifully plane foreground Wasp seven cells cobalt 05 7 x 4 prop Ive seen several Waspsvery im pressive acrobatic craft As understand it will soon kitted Leisure Hurry up Roland glider Electricus also using cobalt 05 7 x 4 seven 800 mAh cells Playboy gets its go six 12 Ah cells powering Leisure 251 gear system Leisure 361 turns Robbe prop Jomar SC-I Speed Control metering out juice seven cells keep Hying Quaker airborne Finally Train-Air 20 pulled cobalt 15 Jomar SC-l between motor 12 cells good Doctor didnt give weights but Playboy covered Micafilin very light material sounds like Doctor John knows important watch Electric weight sure would nice 54 MnrII Aviation 10 well Electrics batteries hold up Bob compared two packs 300 flights other brand-new Both 6-cell Sanyo 12 Ah packs charged con stant current 40 amps lab supply discharged constant 10 amps another pIece equipmsnL Battery voltage measured dIrectly pack terminals fleet Electrics belongs Dr John Mountloy WInston-Salem Ne wnat hying 5151 looks quiet Note thst three planes use Trexier airwheeishelps keep pisnes light Doe must quite pIlot go hot Pattern ship like twin-tailed Wasp lazy-days Old-Timer like Playboyor Saliplanel see Electric Fly thanks both gentlemen sharing photos us really showin us big Electric way Another battery story lot Elec tric flying always take least two planes field Having plane allows charge fly its possible have plane air time Because usually fly flight right after other use conservative safe charge technique previously described MA December 1983 Basically charge technique puts known charge current x time empty battery total amount charge safely below label capacity battery other words dont try fill tank theres much point since can fly nearly continuously anyway means virtually never digital charge approach does put much battery can hold takes longer accomplish dont like standing around waiting pack voltage peakId rather fly set desired current start 15-minute timer go fly something else time switch doing its thing lead-in brings main part story Over past two years Ive accumulated over 300 flights means charges discharges too original Spectra flying done same batteryand its still going strong have taken position battery should last hundreds flights MA December 1983 April 1984 given proper care Since charge technique Ive described never pushes since battery way never pressed limit made heat probably vent during charging consider example proper care just what has happened battery con dition throughout use can give partial answer decided test battery com parison another new neverContinued page 159 THE OLYMPIC V Ace RIC now offers American made alternative plastic imports Olympic V Time proven quality dependability sensible solid package tradition Silver Seven results unit perfect first time R/Cer sport flier So modeler can choose size type price range servo requires Olympic V furnished less servos Any modern positive pulse servos Ace other brand will work system connectors furnished So now alternative Ace Silver Seven performance import price Available approved 50 53 72 mHz channels RECEIVER Proven Silver Seven Design Wired five channels Gold plated Deans connectors 3/4 x 1-11/32 x 2-1/4 14 oz 500 ma Rechargeable Nicds Dual Charger furnished Servo connectors furnished 20G500Olympic V System Assembled $14995 TRANSMITTER Four channels standard fifth channel optional Proven Silver Seven hi output RF deck Open Gimbal Sticks Rugged vinyl clad aluminum case Expended scale voltmeter monitor battery Rechargeable Ni-cd equipped 96V @ 500 ma Offset antenna maximum radiation Send $200 complete catalog Ace items available dealer order direct add $100 handling fee [ACE I/C Em P0 Box 511E Higginsville Mo 64037 816 584-7121 ntmber1QA orIgInaI-aealgn solar-cell-powered Iectrlc Sailplane won 1954 Greater Trenton Science Fair 1 6-year-old Brian Billie Robbinavllie NJ cobalt 05 motor gate up 36 watts power direct sunlight 36 solar cells wing Bob eays isa possibility Brian will fly model years Electric Fly Model Magic Filler Quick setting Light weigbt Nnn Fillets Gap filling Ding repair U See dealer first write call $595 Retail 8 fI oz Model Magic Products Model Magic Products PO Box 7784 St Paul Minn 55119 715 425-1397 Adhesion Balsa Foam Fiberglass Strength Flexing Spreading Fuel Resistance Sanding Hardness Finishing Shelf Ufe Tint Acceptance Water Resistance Comparison Chart Model Magic Exceent Product X Very Poor Good As medium balsa As Hard Balsa Any finish/covering till used up Excellent Soft balsa Soft balsa Spoils 57 mo Very Poor Test methods arid data avalable request care enough fill very best sist Model Magic Filer Circus Magic Filler veloping composite structures Burt Rutan has certainly leaders Proud Youd darn well better believe should too Dee B Mathews 506 South Walnut Greensburg KS 67054 RC ElectricslKopski Continued page 55 used battery Both six-cell 12 Ah Sanyo packs chance just happened run testing time 300 flights previously recorded Un fortunately have break-in data used pack new cant certain flying has af fected battery So purposes experiment made assumption used battery new like new included test Such assumption allows determine much used pack has degraded usesort test consisted six charge/dis charge cycles pack pack carefully charged using regulated lab supply specific time periods shown table charge current used constant 40 amps charge time varied purposes test times varied rela tively short pushing-it long Following charges described pack carefully discharged using electronically-regulated current sink like reverse supply effect packs loaded electronic load such constant discharge current 100 amps flowed batteries under test no matter what terminal voltage discharges carefully timed beginning cutoff purposes test chose cutoff equivalent volt per cell six volts total six-cell packs battery pack voltage dropped value during discharge watch stopped No attempt made deter six cells accounted depressed terminal voltage As turns out much-used pack probably has some noticeable cell imbalance appears some cells did drop deeper rapidly others same pack preceding description clear can tell what percentage charge battery returns Also quite same can tell what Iie] ] d $100 Cash Check Stamps 32 Page Tabloid size illustrated DISCOUNT Catalog Sent 1st Class Mail COMET COX FLYLINE FOX GOLDBERG GUILLOWS JETCO K&3- PACTRA PECK POLYMER PERFECT SIG- STERLING SULLIVAN TOP FLITE & OTHERS PENN VALLEY HONEY CENTER 837 1 Main 3t Lanshli 1 19446 battery capacity battery known fully-charged total ampere-hours important another par ameter also importantthe battery-ter minal voltage battery has high ternal losses terminal voltage under load will depressed flight made way will good flight battery maintains high voltage out put motor Lets look table analyze re sults tests Looking new bat tery first see familiar phenomenon first flights good means its common experience first sometimes second flights day good followthe battery seems go through warm-up though dont think has anything temper ature Anyway first three fiveminute charges apparent charge return battery gradually improves reach level very close charge put other words get charge back performance continues creasingly longer charges up limits testeda sixth cycle input equal SeDtember 1984 159 1 AERONCAC3 GIANT SCALE 4CYcLE6O-90 SEND $200 FOR COMPLETE CATALOG OF FINE KITS IKON NW5T PO Box 566 Auburn WA 98071 206 941-8248 New Model Magic Products Model Magic Epoxy Plus 2 Part 8 Mm Use anywhere two part epoxy used Light weight Sandable Carveable Excellent Gap Filling Non Sagging Superior Strength Sands and carves like basswood! 6 fI oz $895 See dealer first write cal Madel Magic Products Inc ,.P0 Box 19784 St Paul MN 55119 715425-1397 Converting Gb En gines Ignition has advantages such Savings cost fuel Less oily mess no Plugs burn out Use boats Cars Planes helicopters Can adapted Larger engines place Flywheel Thus saving weight No machine work voiced needed screw driver drill Most available Gb en gines can converted features yours won new rn iI6IJ5IL MAKK LDlTwo four cycles pointless sstens no points worry aboutTwins etc unit comes predrilled disk sensor formed clamp mounting sensor engine Complete instructions convertion timing procedures in- Complete cluded Unit operates 48 v Low current drain Weight 2 ozs size 2 x 2 x 75 System inches needed complete system Ignition coil spark plug on/off switch available separately complete system fuel 69 95 ignition lines included No ba e es nc uded State engine size use ordering FABTRONICSCash M 0 Certified Check plus $300 postage handling 15860 Via Riverapersonal checks take time clear Calif residents add tax San Lorenzo CA 94580 Brochure $1 00 refundable purchase label capacity 72 ampere-minutes 12 Ah behavior ter minal voltage during charge think battery could actually hold charge voltage did rise usual values experienced during digital charge Now much-used battery Notice second test cycle brings right up about best can warmed up faster brand-new pack Con tinuing testing now see some funnies fourth cycle results say battery delivered put course cant believe l06o output result some cell imbalance ie some cells probably 4 x 10 ampere-minutes result previous cycle cutoffs being determined some weaker cellsthe better ones did get sufficiently discharged battery empty recharged Anyway numbers may some what error basic message good cared-for batteries can facili tate lot top-quality flying As now move up fifth cycle something different seems taking place apparent charge return per centage seems decreasing substanti ally Notice also end-of-charge terminal voltage rather highmaybe past peak though battery likely certain its cells fully charged sixth run tends confirm suspicion attempt put charge battery produces same discharge ampere-minutes fifth run corresponding lower output/input percen tage venting well Good griefone precious cells actually vented Oh well anything science No isnt first time Ive popped sorta knew gonna happen fact quite warm overcharged pack quickly cooled put back use out suffering much far can see preceding test data evi dent can expect recover nearly battery charge within limits both new well-used well-caredPIANUT SCALS MODELS Kits $595 ZEROMILES M-IB PIETENPOLDRUINE PIPER CUBCOUGAR ANDRESONGIPSY MOTH MUSTANGLACEY M-IOGANAGOBIE jjjjrjWstmd PRAIRIE BIRD 4 KIT $595 SPORT MODELS BABY ACE $649 ONE NITE 28 ONE NIlE Ic 9595 STRINGLESS $495 PECK ROG RADIO 3 LIMPS CONTROLLED Ii and 13 FOOT LONOKITS OR READY TO FLY NOW IN TNREE COLORS ORANGE YELLOW LOW PRICES CATAIX No 25 $150 Pck-Pelyauers PN~l9 4424638 469-8615 L BOX 2498 MA LA MESA CA 92041 batteries Also assuming used originally just like new apparent battery capacity decreases use case looks like about / original capacity remain ing bad considering 300 flights Surely battery does owe anything its still usable Taking look terminal voltage during discharge last cycles both batteries see terminal voltage heavily-used pack notice ably lower new pack little voltage can make big difference mo tor power Im sure plane would show pep longer period new battery However Ive decided leave pack place perhaps rerun tests after another hundred flights just see what happens point rest case properly cared-for batteries can last hundreds flights Please note Im saying same wouldnt true batteries have digitally charged hundreds timesthe fact simply dont have therefore cant tell question whether lessthan-maximum charging good Ill simply redirect attention April 1984 issue page 42 flight histograms plane very bat tery tested show hundreds data points averaging out about 13-minute flight times Period Happy Landings Bob Kopski 25 West End Dr Lans dale PA 19446 RC HelicopterslJolly Continued page 56 sensitive rotor blade Normal blade construction calls hardwood leading edge balsa trailing edge use hardwood important two reasons first gives necessary blade attach ment point second attempts balance rotor blade closer pivoting axis Rotor blades airfoil has its center gravity too far aft pivot point likely flutter commonly seen all-flying tailplanes used RC sailplanes rotor blades too werent Hiller flybar-and-paddle system transmitting necessary aerodynamic dampening rotor system machines would quite unflyable out going too far aerodynam ically speaking flybarless Bell-inputonly system used Horizon Kobe Kiko R-22 must have center-ofgravity-corrected rotor blades perform properly Without flybar aft center gravity first control input would send blade oscillation might never come back equilibrium oscillation would course negate control inputs rotor system Helicopters flybars fly 160 Model Aviation
Edition: Model Aviation - 1984/09
Page Numbers: 54, 55, 159, 160
Radio Control Electrics Bob Kopski BEFORE get some Electric techni cal goodies lets take look some photos Ive received inputs came recent weeks significant its own special way First Brian Bailie Robbinsville NJ original glider design big differenceits solar-powered Now weve heard solar-powered accom plishinents before prob ably ones high-tech big-dol lar backing Brian 16-year-old high school student plane got him first Greater Trenton Science Fair What Im wondering what plane gonna get him Up Last Down event 1984 Electric Fly Brian attended last years meet telling about plans project time model incorporates 17% computer-designed wing section weighs 59 oz loading 75 oz/sq ft Astro 05 Cobalt motor gets its power 36 solar cells wing According Brian solar cells de velop about 36 watts direct sunlight Using Rule Thumb MA April 1984 Power Cruise Watts ht lbs x Wing Loading oz/sq ft case Watts 75 ince 36 28 sure sounds like should fly Brian says does part 59 oz on-board battery pack interpret temporary backup such case flight will improve signif icantly believe Brian didnt say plane name Anyway congratula tions Brian looking forward seeing accomplishment operation Next Dr John Mountjoy Win ston-Salem NC have own pre scription lots rest relaxation impressive fleet kinds Elec trics built over past year-and-a-half make beautiful pic ture So take heart still working first Electricfor doctor reports fly beautifully plane foreground Wasp seven cells cobalt 05 7 x 4 prop Ive seen several Waspsvery im pressive acrobatic craft As understand it will soon kitted Leisure Hurry up Roland glider Electricus also using cobalt 05 7 x 4 seven 800 mAh cells Playboy gets its go six 12 Ah cells powering Leisure 251 gear system Leisure 361 turns Robbe prop Jomar SC-I Speed Control metering out juice seven cells keep Hying Quaker airborne Finally Train-Air 20 pulled cobalt 15 Jomar SC-l between motor 12 cells good Doctor didnt give weights but Playboy covered Micafilin very light material sounds like Doctor John knows important watch Electric weight sure would nice 54 MnrII Aviation 10 well Electrics batteries hold up Bob compared two packs 300 flights other brand-new Both 6-cell Sanyo 12 Ah packs charged con stant current 40 amps lab supply discharged constant 10 amps another pIece equipmsnL Battery voltage measured dIrectly pack terminals fleet Electrics belongs Dr John Mountloy WInston-Salem Ne wnat hying 5151 looks quiet Note thst three planes use Trexier airwheeishelps keep pisnes light Doe must quite pIlot go hot Pattern ship like twin-tailed Wasp lazy-days Old-Timer like Playboyor Saliplanel see Electric Fly thanks both gentlemen sharing photos us really showin us big Electric way Another battery story lot Elec tric flying always take least two planes field Having plane allows charge fly its possible have plane air time Because usually fly flight right after other use conservative safe charge technique previously described MA December 1983 Basically charge technique puts known charge current x time empty battery total amount charge safely below label capacity battery other words dont try fill tank theres much point since can fly nearly continuously anyway means virtually never digital charge approach does put much battery can hold takes longer accomplish dont like standing around waiting pack voltage peakId rather fly set desired current start 15-minute timer go fly something else time switch doing its thing lead-in brings main part story Over past two years Ive accumulated over 300 flights means charges discharges too original Spectra flying done same batteryand its still going strong have taken position battery should last hundreds flights MA December 1983 April 1984 given proper care Since charge technique Ive described never pushes since battery way never pressed limit made heat probably vent during charging consider example proper care just what has happened battery con dition throughout use can give partial answer decided test battery com parison another new neverContinued page 159 THE OLYMPIC V Ace RIC now offers American made alternative plastic imports Olympic V Time proven quality dependability sensible solid package tradition Silver Seven results unit perfect first time R/Cer sport flier So modeler can choose size type price range servo requires Olympic V furnished less servos Any modern positive pulse servos Ace other brand will work system connectors furnished So now alternative Ace Silver Seven performance import price Available approved 50 53 72 mHz channels RECEIVER Proven Silver Seven Design Wired five channels Gold plated Deans connectors 3/4 x 1-11/32 x 2-1/4 14 oz 500 ma Rechargeable Nicds Dual Charger furnished Servo connectors furnished 20G500Olympic V System Assembled $14995 TRANSMITTER Four channels standard fifth channel optional Proven Silver Seven hi output RF deck Open Gimbal Sticks Rugged vinyl clad aluminum case Expended scale voltmeter monitor battery Rechargeable Ni-cd equipped 96V @ 500 ma Offset antenna maximum radiation Send $200 complete catalog Ace items available dealer order direct add $100 handling fee [ACE I/C Em P0 Box 511E Higginsville Mo 64037 816 584-7121 ntmber1QA orIgInaI-aealgn solar-cell-powered Iectrlc Sailplane won 1954 Greater Trenton Science Fair 1 6-year-old Brian Billie Robbinavllie NJ cobalt 05 motor gate up 36 watts power direct sunlight 36 solar cells wing Bob eays isa possibility Brian will fly model years Electric Fly Model Magic Filler Quick setting Light weigbt Nnn Fillets Gap filling Ding repair U See dealer first write call $595 Retail 8 fI oz Model Magic Products Model Magic Products PO Box 7784 St Paul Minn 55119 715 425-1397 Adhesion Balsa Foam Fiberglass Strength Flexing Spreading Fuel Resistance Sanding Hardness Finishing Shelf Ufe Tint Acceptance Water Resistance Comparison Chart Model Magic Exceent Product X Very Poor Good As medium balsa As Hard Balsa Any finish/covering till used up Excellent Soft balsa Soft balsa Spoils 57 mo Very Poor Test methods arid data avalable request care enough fill very best sist Model Magic Filer Circus Magic Filler veloping composite structures Burt Rutan has certainly leaders Proud Youd darn well better believe should too Dee B Mathews 506 South Walnut Greensburg KS 67054 RC ElectricslKopski Continued page 55 used battery Both six-cell 12 Ah Sanyo packs chance just happened run testing time 300 flights previously recorded Un fortunately have break-in data used pack new cant certain flying has af fected battery So purposes experiment made assumption used battery new like new included test Such assumption allows determine much used pack has degraded usesort test consisted six charge/dis charge cycles pack pack carefully charged using regulated lab supply specific time periods shown table charge current used constant 40 amps charge time varied purposes test times varied rela tively short pushing-it long Following charges described pack carefully discharged using electronically-regulated current sink like reverse supply effect packs loaded electronic load such constant discharge current 100 amps flowed batteries under test no matter what terminal voltage discharges carefully timed beginning cutoff purposes test chose cutoff equivalent volt per cell six volts total six-cell packs battery pack voltage dropped value during discharge watch stopped No attempt made deter six cells accounted depressed terminal voltage As turns out much-used pack probably has some noticeable cell imbalance appears some cells did drop deeper rapidly others same pack preceding description clear can tell what percentage charge battery returns Also quite same can tell what Iie] ] d $100 Cash Check Stamps 32 Page Tabloid size illustrated DISCOUNT Catalog Sent 1st Class Mail COMET COX FLYLINE FOX GOLDBERG GUILLOWS JETCO K&3- PACTRA PECK POLYMER PERFECT SIG- STERLING SULLIVAN TOP FLITE & OTHERS PENN VALLEY HONEY CENTER 837 1 Main 3t Lanshli 1 19446 battery capacity battery known fully-charged total ampere-hours important another par ameter also importantthe battery-ter minal voltage battery has high ternal losses terminal voltage under load will depressed flight made way will good flight battery maintains high voltage out put motor Lets look table analyze re sults tests Looking new bat tery first see familiar phenomenon first flights good means its common experience first sometimes second flights day good followthe battery seems go through warm-up though dont think has anything temper ature Anyway first three fiveminute charges apparent charge return battery gradually improves reach level very close charge put other words get charge back performance continues creasingly longer charges up limits testeda sixth cycle input equal SeDtember 1984 159 1 AERONCAC3 GIANT SCALE 4CYcLE6O-90 SEND $200 FOR COMPLETE CATALOG OF FINE KITS IKON NW5T PO Box 566 Auburn WA 98071 206 941-8248 New Model Magic Products Model Magic Epoxy Plus 2 Part 8 Mm Use anywhere two part epoxy used Light weight Sandable Carveable Excellent Gap Filling Non Sagging Superior Strength Sands and carves like basswood! 6 fI oz $895 See dealer first write cal Madel Magic Products Inc ,.P0 Box 19784 St Paul MN 55119 715425-1397 Converting Gb En gines Ignition has advantages such Savings cost fuel Less oily mess no Plugs burn out Use boats Cars Planes helicopters Can adapted Larger engines place Flywheel Thus saving weight No machine work voiced needed screw driver drill Most available Gb en gines can converted features yours won new rn iI6IJ5IL MAKK LDlTwo four cycles pointless sstens no points worry aboutTwins etc unit comes predrilled disk sensor formed clamp mounting sensor engine Complete instructions convertion timing procedures in- Complete cluded Unit operates 48 v Low current drain Weight 2 ozs size 2 x 2 x 75 System inches needed complete system Ignition coil spark plug on/off switch available separately complete system fuel 69 95 ignition lines included No ba e es nc uded State engine size use ordering FABTRONICSCash M 0 Certified Check plus $300 postage handling 15860 Via Riverapersonal checks take time clear Calif residents add tax San Lorenzo CA 94580 Brochure $1 00 refundable purchase label capacity 72 ampere-minutes 12 Ah behavior ter minal voltage during charge think battery could actually hold charge voltage did rise usual values experienced during digital charge Now much-used battery Notice second test cycle brings right up about best can warmed up faster brand-new pack Con tinuing testing now see some funnies fourth cycle results say battery delivered put course cant believe l06o output result some cell imbalance ie some cells probably 4 x 10 ampere-minutes result previous cycle cutoffs being determined some weaker cellsthe better ones did get sufficiently discharged battery empty recharged Anyway numbers may some what error basic message good cared-for batteries can facili tate lot top-quality flying As now move up fifth cycle something different seems taking place apparent charge return per centage seems decreasing substanti ally Notice also end-of-charge terminal voltage rather highmaybe past peak though battery likely certain its cells fully charged sixth run tends confirm suspicion attempt put charge battery produces same discharge ampere-minutes fifth run corresponding lower output/input percen tage venting well Good griefone precious cells actually vented Oh well anything science No isnt first time Ive popped sorta knew gonna happen fact quite warm overcharged pack quickly cooled put back use out suffering much far can see preceding test data evi dent can expect recover nearly battery charge within limits both new well-used well-caredPIANUT SCALS MODELS Kits $595 ZEROMILES M-IB PIETENPOLDRUINE PIPER CUBCOUGAR ANDRESONGIPSY MOTH MUSTANGLACEY M-IOGANAGOBIE jjjjrjWstmd PRAIRIE BIRD 4 KIT $595 SPORT MODELS BABY ACE $649 ONE NITE 28 ONE NIlE Ic 9595 STRINGLESS $495 PECK ROG RADIO 3 LIMPS CONTROLLED Ii and 13 FOOT LONOKITS OR READY TO FLY NOW IN TNREE COLORS ORANGE YELLOW LOW PRICES CATAIX No 25 $150 Pck-Pelyauers PN~l9 4424638 469-8615 L BOX 2498 MA LA MESA CA 92041 batteries Also assuming used originally just like new apparent battery capacity decreases use case looks like about / original capacity remain ing bad considering 300 flights Surely battery does owe anything its still usable Taking look terminal voltage during discharge last cycles both batteries see terminal voltage heavily-used pack notice ably lower new pack little voltage can make big difference mo tor power Im sure plane would show pep longer period new battery However Ive decided leave pack place perhaps rerun tests after another hundred flights just see what happens point rest case properly cared-for batteries can last hundreds flights Please note Im saying same wouldnt true batteries have digitally charged hundreds timesthe fact simply dont have therefore cant tell question whether lessthan-maximum charging good Ill simply redirect attention April 1984 issue page 42 flight histograms plane very bat tery tested show hundreds data points averaging out about 13-minute flight times Period Happy Landings Bob Kopski 25 West End Dr Lans dale PA 19446 RC HelicopterslJolly Continued page 56 sensitive rotor blade Normal blade construction calls hardwood leading edge balsa trailing edge use hardwood important two reasons first gives necessary blade attach ment point second attempts balance rotor blade closer pivoting axis Rotor blades airfoil has its center gravity too far aft pivot point likely flutter commonly seen all-flying tailplanes used RC sailplanes rotor blades too werent Hiller flybar-and-paddle system transmitting necessary aerodynamic dampening rotor system machines would quite unflyable out going too far aerodynam ically speaking flybarless Bell-inputonly system used Horizon Kobe Kiko R-22 must have center-ofgravity-corrected rotor blades perform properly Without flybar aft center gravity first control input would send blade oscillation might never come back equilibrium oscillation would course negate control inputs rotor system Helicopters flybars fly 160 Model Aviation