WHILE flying control line model airplane a28year-old man electrocuted metal control wires contacted uninsulated power lines traversing field plane being flown above statement synopsis included accident report file Consumer Product Safety Commission eight similar reports involving contact power lines CL model occurred last six years seven incidents modeler died hard believe control-line fliers would deliberately fly models close power lines However observed such practice talting place just last year Nationals Lincoln Nebraska Several fellows fun flying ball field just outside dormitory accommodated Sur rounding field power lines lighting system Fortunately nobody misfortune contact lines years ago witnessed what could easily have tragic accident caused contact overhead power lines time living England member Vickers Armstrongs model club use several playing fields control line flying whenever use soccer cricket Traversing edge fields canal following canal power lines part National Grid believe carried voltage of67OOO volts day incident stiff breeze blowing its always windy England towards lines modeler took off rich engine setting trouble keeping control lines taught model upwind As might guess time lines started go slack took several paces downwind After dozen laps obvious rest us practice continued would danger contacting power lines began shouting him alert him peril sound engine drowned out voices end flight came models outboard wing cut off power lines Six inches closer would have lost friends theorize incidents electrocution have occurred did because modeler moved position during flight probably because wind causing lines go slack accident reports involving electrocu tion control line fliers power lines contacted carried several thousand volts voltages contact wires necessary receive shock Close proximity high voltage source grounded body can result arc jumping gap Generally speaking takes about 70000 volts arc bridge one-inch gap Fortunately overhead power transmission lines lower voltages figure bear mind current maximum permitted country 765000 volts Lest discussion ofelectrocution sources thousands volts should give false sense security dealing mere 120 volt outlets home lets take quick look mechanism electric shock Most us have probably contacted electrically live wire home have felt either tingling sensation distinct jolt depending much current passed through bodies Notice used word current rather voltage voltage electrical source large extent determines its hazard amount current flows through body its duration will determine end result example lets suppose standing carpeted floor touch finger electrical source 120 volts voltage household electrical appliances including such items soldering irons power drills saws battery chargers other electrical items ~k1ILI1 COMES FIRST Electrocution far greatest hazard modeler Contact power lines ac counted eight deaths six years danger ous shocks can occur carelessness shop equipment battery chargers Such accidents would never happen modeler read page spread word may save life John Preston use pursuit hobby have dry hands such situation will often feel merely tingling sensation point contact nerve endings finger being stimula ted sensations touch warmth some people sensation can produced current flow 05 milliamps current commonly known threshold perception Since workshops of modelers know located basement houses no dont live Florida likely going contact live wire household voltage 120 volts will standing concrete floor perhaps bare feet Now have what could serious situation body now grounded provides ready path flow electricity tingling sensation now changes distinct jolt muscles involuntary contract live electrical wire grasped paim hand current flow reaches about 10 milliamps possible involuntary contraction muscles will prevent us letting go wire decidedly unpleasant situation Electrocution deaths usually caused fibrillation heart Instead beating normal rythm heart muscles contract rapidly irregularly person condition will die very quickly Filbriliation heart can caused current flow through body low 50 milliamps much current use recharge average RC airborne flight pack might asking dont get lethal shock wires connect up NiCads battery charger Simple output voltage battery charger bodies have sufficient electrical resistance prevent current flow ofSO milliamps course grasping input wires 120 volts different story subject battery chargers chargers used RC equipment use trans former obtain correct output Some older models frequently used dropping resistor con nected series single diode obtain appropriate DC voltage happen have always connect batteries charger before plugging unit wall socket Conversely always disconnect plug wall receptable first dropping resistors work transformers isolate output high voltage input much safer point discussion give some idea small current flow required cause electrical shock actual current will flow through body contacts electrical source given voltage will vary according source contacted finger touch versus whole hand grasp etc well grounded Generally speaking AC voltages below 30 volts will insufficient cause lethal current flow Returning subject contact overhead power lines aimost uninsulated power lines likely located around flying sites going potentials several thousand volts Lest thought some relatively long small diameter model control lines will produce effective dropping resistor between electrical source flier let us correct know case person flying kite line contained metallized thread Such thread has amuch greater resistance smallest diameter steel wire used control line flying person electrocuted kite fell across power line has suggested some form insulator between control lines handle should used doubtful insulator would protect person source over 100000 volts some power lines exceedthis value couldbe devised wouldnt also interfere control model conventional two-line system An insulating device suggested article appeared 1976 journal International Association Electrical Inspectors writer article also suggested about Underwriters Labs taking up coming up Listing set standards airplanes about indeed want happen would rather avoid accident flying locations devoid power lines Although seldom fly CL models days know alternative prefer Although its life talking about may think have right what wish give some thought fact name Continued page 96 February 1980 25 two classics Flyline COMING SOON 11/2 Scale Farman Moustique READY NOW 47iiCO BO Products BOBCO parts factory parts replacement parts manufactured BOBCO Call Write Complete Information Entire Line DEALER PROGRAMS ENCOURAGED SEE YOUR LOCAL HOBBY DEALER send 25f catalog _____________34 span ower single channel or$1595 free flight OUAKER FLASH FLYLINE MODELS INC 2820 DOAR AVENUE B-Il FAIRFAX VIRGINIA 22031 703 573-2030 BLADES JET RANGER$1295 ALLOUETE$1295 COMMANDER$895 HELIBOY$895 HELIBABY$495 REVOLUTION 1$495 ROTOR SHAFTS HELIBABY$495 COMMANDER$995 REVOLUTION 1$495 FAN SHROUDS 40 60 size$795 Have AMERICAN KAVAN Helicoptors parts DISCOUNT PRICES 10% Discount 5 Sets CA residents add 6% sales tax2504 C-i S Santa Fe Avenue add $150 postage & handlingVista CA 92083 check moncy order toTel 714 727 41304 Openers/Winter continued page 72 forgiven being doubting Thomas Everything completely obvious scrutable Quarter- Scale movement biggies general apparently has encountered its first headache dire predictions having far fallen faces problem did show itself proved electronic Gremlin-like nature does affect such craft perhaps unlucky victim phenomena wont find very funny According memorandum AMA Frequency Committee RC Modelers RC Radio Manufacturers sent Quarter-Scale Association some planes just flat unflyable Noise ancient nemesis caused universal grief some years ago like insects develop immunity pesticides once again major challenge Present radios have dealt problem ordinary airplanes biggies ordinary airplanes know importance avoiding metal-to-metal contacts though modem radios have eliminated great deal such self-generated interference padded circuits noise resistant memo compared approach caging wild tiger some minor problem breaks lock hell can burst loose Large engines can vibrate like buzz saws metal fittings strength occasional ships require spiderweb rigging wires No mention made cable control wires running over place possible interaction between things servo cables antennas possibly wires cables may create other spooky problems though FO quali fied wonder Fortunately QSAA has world-wide experience conclusive evidence FM radios eliminate problem memo urges drive obtain FCC approval FM frequencies will report now matter being pursued AMA FCC receptive granting new FM frequencies RC will reading about AMA section magazine action unfolds editor fully convinced contact quarter-scaler friends problem can acute has unflyable 60-powered job flight disaster spite interchang ing Kraft Futaba systems have file expensive project also manufactured some later date both designer manufacturer ask us run warning note may unflyable manufacturer has post poned full line lovely biggies afraid flight test until answer found Mean takes good old AMA get frequencies AMA s current effort may solve problem Whatever outcome takes oh much timeit encouraging see alert QSAA effective on-the-ball organization getting word out warn others John Prestons column Safety month may important thing have ever read has unpleasant things say about fatal accidents flying CL models near powerlines editor helm ofMANmany years ago record kept fatalities appeared both US British newspapers ten-year period count stood 16 prior 1960 Preston mentions eight over past six years Manufacturers have driven out businessand constant threat radio too other reasonssince todays practice people sue everyone sight manufacturers props wheels parts AMA itself free concern speak ing CL models writer Matty Sullivan once investigated matter power companies New York Philadelphiaboth printed literature combat problem advised Preston says model does actually have touch such lines control lines may metal told electrical current jumps gap will follow direction must try educate everyone far wide please report type model accident Preston guidance column Safety Preston continued page 25 coroners report may step closer having some outside legislation affecting hobby rest us DO NOT FLY NEAR OVERHEAD POWER LINES John Preston 7012 Elsira Ct Falls Church VA 22042 96 Model Aviation Norman Walker demonstration model referred FO the right wont fly efficiently normal model horizontal tail small flat plate ward slanted fin provides drag stabilizes airplane pitch Left Another oddities straight-winged tail-less 1/4 camber airfoil inverted After half out side loop following launching will stabilize fly invertedknew youd curious
Edition: Model Aviation - 1980/02
Page Numbers: 25, 96
WHILE flying control line model airplane a28year-old man electrocuted metal control wires contacted uninsulated power lines traversing field plane being flown above statement synopsis included accident report file Consumer Product Safety Commission eight similar reports involving contact power lines CL model occurred last six years seven incidents modeler died hard believe control-line fliers would deliberately fly models close power lines However observed such practice talting place just last year Nationals Lincoln Nebraska Several fellows fun flying ball field just outside dormitory accommodated Sur rounding field power lines lighting system Fortunately nobody misfortune contact lines years ago witnessed what could easily have tragic accident caused contact overhead power lines time living England member Vickers Armstrongs model club use several playing fields control line flying whenever use soccer cricket Traversing edge fields canal following canal power lines part National Grid believe carried voltage of67OOO volts day incident stiff breeze blowing its always windy England towards lines modeler took off rich engine setting trouble keeping control lines taught model upwind As might guess time lines started go slack took several paces downwind After dozen laps obvious rest us practice continued would danger contacting power lines began shouting him alert him peril sound engine drowned out voices end flight came models outboard wing cut off power lines Six inches closer would have lost friends theorize incidents electrocution have occurred did because modeler moved position during flight probably because wind causing lines go slack accident reports involving electrocu tion control line fliers power lines contacted carried several thousand volts voltages contact wires necessary receive shock Close proximity high voltage source grounded body can result arc jumping gap Generally speaking takes about 70000 volts arc bridge one-inch gap Fortunately overhead power transmission lines lower voltages figure bear mind current maximum permitted country 765000 volts Lest discussion ofelectrocution sources thousands volts should give false sense security dealing mere 120 volt outlets home lets take quick look mechanism electric shock Most us have probably contacted electrically live wire home have felt either tingling sensation distinct jolt depending much current passed through bodies Notice used word current rather voltage voltage electrical source large extent determines its hazard amount current flows through body its duration will determine end result example lets suppose standing carpeted floor touch finger electrical source 120 volts voltage household electrical appliances including such items soldering irons power drills saws battery chargers other electrical items ~k1ILI1 COMES FIRST Electrocution far greatest hazard modeler Contact power lines ac counted eight deaths six years danger ous shocks can occur carelessness shop equipment battery chargers Such accidents would never happen modeler read page spread word may save life John Preston use pursuit hobby have dry hands such situation will often feel merely tingling sensation point contact nerve endings finger being stimula ted sensations touch warmth some people sensation can produced current flow 05 milliamps current commonly known threshold perception Since workshops of modelers know located basement houses no dont live Florida likely going contact live wire household voltage 120 volts will standing concrete floor perhaps bare feet Now have what could serious situation body now grounded provides ready path flow electricity tingling sensation now changes distinct jolt muscles involuntary contract live electrical wire grasped paim hand current flow reaches about 10 milliamps possible involuntary contraction muscles will prevent us letting go wire decidedly unpleasant situation Electrocution deaths usually caused fibrillation heart Instead beating normal rythm heart muscles contract rapidly irregularly person condition will die very quickly Filbriliation heart can caused current flow through body low 50 milliamps much current use recharge average RC airborne flight pack might asking dont get lethal shock wires connect up NiCads battery charger Simple output voltage battery charger bodies have sufficient electrical resistance prevent current flow ofSO milliamps course grasping input wires 120 volts different story subject battery chargers chargers used RC equipment use trans former obtain correct output Some older models frequently used dropping resistor con nected series single diode obtain appropriate DC voltage happen have always connect batteries charger before plugging unit wall socket Conversely always disconnect plug wall receptable first dropping resistors work transformers isolate output high voltage input much safer point discussion give some idea small current flow required cause electrical shock actual current will flow through body contacts electrical source given voltage will vary according source contacted finger touch versus whole hand grasp etc well grounded Generally speaking AC voltages below 30 volts will insufficient cause lethal current flow Returning subject contact overhead power lines aimost uninsulated power lines likely located around flying sites going potentials several thousand volts Lest thought some relatively long small diameter model control lines will produce effective dropping resistor between electrical source flier let us correct know case person flying kite line contained metallized thread Such thread has amuch greater resistance smallest diameter steel wire used control line flying person electrocuted kite fell across power line has suggested some form insulator between control lines handle should used doubtful insulator would protect person source over 100000 volts some power lines exceedthis value couldbe devised wouldnt also interfere control model conventional two-line system An insulating device suggested article appeared 1976 journal International Association Electrical Inspectors writer article also suggested about Underwriters Labs taking up coming up Listing set standards airplanes about indeed want happen would rather avoid accident flying locations devoid power lines Although seldom fly CL models days know alternative prefer Although its life talking about may think have right what wish give some thought fact name Continued page 96 February 1980 25 two classics Flyline COMING SOON 11/2 Scale Farman Moustique READY NOW 47iiCO BO Products BOBCO parts factory parts replacement parts manufactured BOBCO Call Write Complete Information Entire Line DEALER PROGRAMS ENCOURAGED SEE YOUR LOCAL HOBBY DEALER send 25f catalog _____________34 span ower single channel or$1595 free flight OUAKER FLASH FLYLINE MODELS INC 2820 DOAR AVENUE B-Il FAIRFAX VIRGINIA 22031 703 573-2030 BLADES JET RANGER$1295 ALLOUETE$1295 COMMANDER$895 HELIBOY$895 HELIBABY$495 REVOLUTION 1$495 ROTOR SHAFTS HELIBABY$495 COMMANDER$995 REVOLUTION 1$495 FAN SHROUDS 40 60 size$795 Have AMERICAN KAVAN Helicoptors parts DISCOUNT PRICES 10% Discount 5 Sets CA residents add 6% sales tax2504 C-i S Santa Fe Avenue add $150 postage & handlingVista CA 92083 check moncy order toTel 714 727 41304 Openers/Winter continued page 72 forgiven being doubting Thomas Everything completely obvious scrutable Quarter- Scale movement biggies general apparently has encountered its first headache dire predictions having far fallen faces problem did show itself proved electronic Gremlin-like nature does affect such craft perhaps unlucky victim phenomena wont find very funny According memorandum AMA Frequency Committee RC Modelers RC Radio Manufacturers sent Quarter-Scale Association some planes just flat unflyable Noise ancient nemesis caused universal grief some years ago like insects develop immunity pesticides once again major challenge Present radios have dealt problem ordinary airplanes biggies ordinary airplanes know importance avoiding metal-to-metal contacts though modem radios have eliminated great deal such self-generated interference padded circuits noise resistant memo compared approach caging wild tiger some minor problem breaks lock hell can burst loose Large engines can vibrate like buzz saws metal fittings strength occasional ships require spiderweb rigging wires No mention made cable control wires running over place possible interaction between things servo cables antennas possibly wires cables may create other spooky problems though FO quali fied wonder Fortunately QSAA has world-wide experience conclusive evidence FM radios eliminate problem memo urges drive obtain FCC approval FM frequencies will report now matter being pursued AMA FCC receptive granting new FM frequencies RC will reading about AMA section magazine action unfolds editor fully convinced contact quarter-scaler friends problem can acute has unflyable 60-powered job flight disaster spite interchang ing Kraft Futaba systems have file expensive project also manufactured some later date both designer manufacturer ask us run warning note may unflyable manufacturer has post poned full line lovely biggies afraid flight test until answer found Mean takes good old AMA get frequencies AMA s current effort may solve problem Whatever outcome takes oh much timeit encouraging see alert QSAA effective on-the-ball organization getting word out warn others John Prestons column Safety month may important thing have ever read has unpleasant things say about fatal accidents flying CL models near powerlines editor helm ofMANmany years ago record kept fatalities appeared both US British newspapers ten-year period count stood 16 prior 1960 Preston mentions eight over past six years Manufacturers have driven out businessand constant threat radio too other reasonssince todays practice people sue everyone sight manufacturers props wheels parts AMA itself free concern speak ing CL models writer Matty Sullivan once investigated matter power companies New York Philadelphiaboth printed literature combat problem advised Preston says model does actually have touch such lines control lines may metal told electrical current jumps gap will follow direction must try educate everyone far wide please report type model accident Preston guidance column Safety Preston continued page 25 coroners report may step closer having some outside legislation affecting hobby rest us DO NOT FLY NEAR OVERHEAD POWER LINES John Preston 7012 Elsira Ct Falls Church VA 22042 96 Model Aviation Norman Walker demonstration model referred FO the right wont fly efficiently normal model horizontal tail small flat plate ward slanted fin provides drag stabilizes airplane pitch Left Another oddities straight-winged tail-less 1/4 camber airfoil inverted After half out side loop following launching will stabilize fly invertedknew youd curious