IF YOU sailplane HLG enthusiast months column safety may value subject discussion hazard rotating component majority powered model aircraftthe propeller doubt readers regularly fly engine-powered models havent some time another come contact rotating prop Most often happens adjusting needle valve since majority models use tractor propeller set-up rather pusher behind prop Contact rear surface prop blade usually results minimal no damage human digit shape blade merely knocks ones fingers hand out way exceptions general case will see However injuries fingers hand require some form medical treatment often result contact propeller blades front leading edge such case prop blade shape tends drag contacting member further arc resulting motor stoppage blade breakage finger breakage Serious lacerations amputations have resulted know no positive solution contact propellers Electric starters now com mon-place lot modelers field boxes go long way reducing finger injuries during engine starting operation As needle valve tweekers can say Careful Since popular engine induction via front rotary valve carburetor its attendant mixture control needle valve very close propeller arc flexible shaft needle valve can angled rearward goes long way making adjustments mixer safer real hazard propellers some extent spinners fracture blade during operation engine last months column briefly mentioned incident fracture blade carbon fiber/resin pro peller cost French modeler life pierced aorta speculated over tightening prop retaining nut may have produced stresses combined stresses due blade flexing precipitated disaster Another account propeller blade failure very graphically reported July 1979 news letter Ames Sundusters think following account well worth repeating Propellersnow subject need RC CL oriented fly powered models least part-time use props least havent seen ducted fans yet Due several factors inherent operation propellers high speeds involved vulnerable position occupied prop combining possible carelessness inexperience propellers can become dangerous part model Consider moment speeds involved Tip speeds may come shock Lets run TD 049 15000 rpm 6-3 prop Sounds pretty tame right tips prop whirling along sedate 270 mph about sport 40 10-inch prop Lets say 11000 rpm another tame engine tips considerably better TD almost 360 mph means dealing poten tially lethal initial velocities blade separates someone could hurt very badly So keep spec tators out arc prop know often like hang over shoulder adjust engine politely move back keep yourself out line fire too includes front plane Just keep living things behind running engine Ill give dum-dum experience now Know prop instructions say boil QAUUi rv 7AIId AK COMES FIRST Props prime cause accidentssome quite serious arent aware beware tips months article may suggest mend waysright now U John Preston nylon props 29 adjusting carburetor running old nylon prop got box ofjunk knew old because brand no longer looks way prop looked Anyway tweaking needle valve got very tip finger prop blade let go instant hit squarely between eyes hurt partly because wearing sungiasses partly because engine full throttle Now prop looked brand new dried out Three dumb tricks will almost always add up accident Keep face away prop dont stick fingers boil it nylon fact manufacturers put out very good little instruction sheetsRead Heed SAFETY FIRST So have modelers experi ence propeller might easily have resulted very serious injury ever another side coin browsing through file AMA HQ recently search material column came across copy letter modeler sent manufacturer spinners manufacturer includes products some instruc tions precautions us readily recognize hazards associated whirling props perhaps less aware fact spinners have known fly apart too following 10 items printed sheet accompanies spinner manufacturer ships well worth reading heeding 1 Always make round curved cut-out propeller opening leave sharp corner 2 Most spinners come off because propel ler loose use 4-way glow plug wrench tighten propelleruse least 6-in wrench Make sure propeller tight time start engine use soft wood propellers wood crushes comes loose 3 Do lean over reach over propel ler-spinner combination Get behind air plane adjust engine running 4 Wear safety giasses near running engine 5 Do run plastic spinner over 12000 rpm 6 Do run metal spinner over 18000 rpm 7 When tightening spinner onto backplate center screw sure spinner centered properly backplate groove over-tighten turn center screw after becomes snug Any plastic part can broken big screwdriver 8 Do run plastic spinner temperatures below 360F below 1 0C 9 Always check spinner cracks before using use spinner size crack 10 little care common sense will cure lot problems Always balance propeller spinner Almost radio failures caused vibration little care equipment will last lot longer exception #2 instructions followed should go long way preventing modelers being struck fragment thrown rotating spinner prop regard size wrench should used tighten prop much depends modelers own strength Some hairy-armed people know could easily damage prop retalning nut given 6-in wrench Now letter written spinner manufacturer irate modeler Id bet probably doesnt wear seat belt driving car What want know wrote new instruction sheet laminated plastic spinnersan engineer attorney Ill bet attorney same guy advised name prop mfr put some overly cautious advice propellers example both prop mfr now saying pilot should get behind plane adjust engine Did try likely stumble over field box have number other difficulties move around holding onto plane just following present practice adjusting engine front reason am sensitive sooner later some insurance company going resist claim offer smaller amount because individual did follow manufacturers instruc tions individual will fighting both insurance company manufacturer safety glass idea None corrected sufficiently flying saying put start engine take off before taking off handling bound become fuel damaged stepped guy wears glasses sup posed put safety goggles over regular glasses invest safety glasses just flying Have enough accident reports support Continued page 126 70 Model Aviation THE THIRD ANNUAL 3 JANUARY 12& 13 1980 SEE THE LATEST PRODUCTS AND VISIT WITH MAJOR MANUFACTURERS AND DISTRIBUTORS OF MODEL AIRCRAFT* MODEL ENGINES MODEL BOATS RADIO CONTROL SYSTEMS eMODELCARSI*MODELINGACCESSORIES INDOOR DEMONSTRATIONS STATIC DISPLAY COMPETITION IN MANY CATEGORIES OVERSEAS EXHIBITORS CORDIALL Y INVIJftI INTERNATIONAL MODELER SHOW BOX 127 COSTA MESA CA 92627 714 548-4700 banked turns stayed right put aileron response great full power no flutter visible engine leaned out little stayed rich Response hands pilot After few fly-bys time landing remembered Dean instructions recommended three-point flair out Thats way was real joy see No pattern flying yet need training checkout time see no reason expect best airplane Besides week late story deadline See ya around next adventure We-Fly Lab Safety Preston continued page 70 kind requirement since plastic spinners 2apable going over 12000 rpm Perryported Supertigre 60 does 12900 add pipe will go 14000 must go metal spinner Weve no problem plastic rpm metal limit 18000 Are nylon ducted fan units hitting 22500 Youridea using 4-way wrench also over-cautious darn aluminum nuts will strip threads use too much force loosening problem 4-way turned down snugly change humidity say tighten time fire up Nobody does am modeler does like way protecting legal hide expense modeler Offer realistic instructions Ive no doubt will readers will feel letter-writer has point too will probably ignore safety precautions included modeling products Its yourhide trying protect Unfortu nately have accident chances will seeking help others Lets spoil pleasure because carelessness As write second column safety still some two months away publica tion first column Nevertheless Im already getting lot feedback accidents happening fellow modelers through club newsletters mailed AMA Head quarters far common reported incidents involving lacerations pro pellers example engine started rpm much higher expected able hold alrplane prop struck him left arm above elbow prop cut brachial artery median nerve muscle nicked bone before breaking newsletter article goes say arm now cast control movement until heals thumb first two fingers numb tingle have limited mobility present think would agree small change past operating procedures might well worthwhile avoid type injury particular case engine apparently inadvertently started high throttle un expected burst power could handled victim Editor always start engines half-throttleor less will start way finish months sermon have tip comes Jerry Gotts writing DCRC newsletter Jerry clubs safety director happens safety-conscious modelers know Which just goes show us immune accidents Jerry recently have stitches close lacerations three fingers caused contact black glassfilled resin prop props almost totally invisible running engine Jerry suggests prop tips painted white visibility also offers 10 other safety tips regarding pro pellers reproduce benefit 1 Tighten prop nut least beginning flying day 2 Position radio side front prop wont have reach behind prop operate radio sure radio throttle control operating 3 Start engine low throttlenot wide open 4 Keep face away rotating plane prop 5 Use chicken stick electric starter 6 Take extreme caution glow plug wire also removing same engine 7 Examine props often cracks chips balance 8 Give meat grinder wide berth respect commands 9 Always keep uppermost conscious mind spacial relationship hands body spinning prop aware what prop blast may doing others Think about engine thrust might move pivot plane should slip get away 10 Move slowly deliberately think think think. think would add other item Jerrys list needle valve tweaking throttle twiddling behind prop Have safe month John Preston 7012 Elvira Ct Falls Church VA 22042 126 Model Aviation
Edition: Model Aviation - 1980/01
Page Numbers: 70, 126
IF YOU sailplane HLG enthusiast months column safety may value subject discussion hazard rotating component majority powered model aircraftthe propeller doubt readers regularly fly engine-powered models havent some time another come contact rotating prop Most often happens adjusting needle valve since majority models use tractor propeller set-up rather pusher behind prop Contact rear surface prop blade usually results minimal no damage human digit shape blade merely knocks ones fingers hand out way exceptions general case will see However injuries fingers hand require some form medical treatment often result contact propeller blades front leading edge such case prop blade shape tends drag contacting member further arc resulting motor stoppage blade breakage finger breakage Serious lacerations amputations have resulted know no positive solution contact propellers Electric starters now com mon-place lot modelers field boxes go long way reducing finger injuries during engine starting operation As needle valve tweekers can say Careful Since popular engine induction via front rotary valve carburetor its attendant mixture control needle valve very close propeller arc flexible shaft needle valve can angled rearward goes long way making adjustments mixer safer real hazard propellers some extent spinners fracture blade during operation engine last months column briefly mentioned incident fracture blade carbon fiber/resin pro peller cost French modeler life pierced aorta speculated over tightening prop retaining nut may have produced stresses combined stresses due blade flexing precipitated disaster Another account propeller blade failure very graphically reported July 1979 news letter Ames Sundusters think following account well worth repeating Propellersnow subject need RC CL oriented fly powered models least part-time use props least havent seen ducted fans yet Due several factors inherent operation propellers high speeds involved vulnerable position occupied prop combining possible carelessness inexperience propellers can become dangerous part model Consider moment speeds involved Tip speeds may come shock Lets run TD 049 15000 rpm 6-3 prop Sounds pretty tame right tips prop whirling along sedate 270 mph about sport 40 10-inch prop Lets say 11000 rpm another tame engine tips considerably better TD almost 360 mph means dealing poten tially lethal initial velocities blade separates someone could hurt very badly So keep spec tators out arc prop know often like hang over shoulder adjust engine politely move back keep yourself out line fire too includes front plane Just keep living things behind running engine Ill give dum-dum experience now Know prop instructions say boil QAUUi rv 7AIId AK COMES FIRST Props prime cause accidentssome quite serious arent aware beware tips months article may suggest mend waysright now U John Preston nylon props 29 adjusting carburetor running old nylon prop got box ofjunk knew old because brand no longer looks way prop looked Anyway tweaking needle valve got very tip finger prop blade let go instant hit squarely between eyes hurt partly because wearing sungiasses partly because engine full throttle Now prop looked brand new dried out Three dumb tricks will almost always add up accident Keep face away prop dont stick fingers boil it nylon fact manufacturers put out very good little instruction sheetsRead Heed SAFETY FIRST So have modelers experi ence propeller might easily have resulted very serious injury ever another side coin browsing through file AMA HQ recently search material column came across copy letter modeler sent manufacturer spinners manufacturer includes products some instruc tions precautions us readily recognize hazards associated whirling props perhaps less aware fact spinners have known fly apart too following 10 items printed sheet accompanies spinner manufacturer ships well worth reading heeding 1 Always make round curved cut-out propeller opening leave sharp corner 2 Most spinners come off because propel ler loose use 4-way glow plug wrench tighten propelleruse least 6-in wrench Make sure propeller tight time start engine use soft wood propellers wood crushes comes loose 3 Do lean over reach over propel ler-spinner combination Get behind air plane adjust engine running 4 Wear safety giasses near running engine 5 Do run plastic spinner over 12000 rpm 6 Do run metal spinner over 18000 rpm 7 When tightening spinner onto backplate center screw sure spinner centered properly backplate groove over-tighten turn center screw after becomes snug Any plastic part can broken big screwdriver 8 Do run plastic spinner temperatures below 360F below 1 0C 9 Always check spinner cracks before using use spinner size crack 10 little care common sense will cure lot problems Always balance propeller spinner Almost radio failures caused vibration little care equipment will last lot longer exception #2 instructions followed should go long way preventing modelers being struck fragment thrown rotating spinner prop regard size wrench should used tighten prop much depends modelers own strength Some hairy-armed people know could easily damage prop retalning nut given 6-in wrench Now letter written spinner manufacturer irate modeler Id bet probably doesnt wear seat belt driving car What want know wrote new instruction sheet laminated plastic spinnersan engineer attorney Ill bet attorney same guy advised name prop mfr put some overly cautious advice propellers example both prop mfr now saying pilot should get behind plane adjust engine Did try likely stumble over field box have number other difficulties move around holding onto plane just following present practice adjusting engine front reason am sensitive sooner later some insurance company going resist claim offer smaller amount because individual did follow manufacturers instruc tions individual will fighting both insurance company manufacturer safety glass idea None corrected sufficiently flying saying put start engine take off before taking off handling bound become fuel damaged stepped guy wears glasses sup posed put safety goggles over regular glasses invest safety glasses just flying Have enough accident reports support Continued page 126 70 Model Aviation THE THIRD ANNUAL 3 JANUARY 12& 13 1980 SEE THE LATEST PRODUCTS AND VISIT WITH MAJOR MANUFACTURERS AND DISTRIBUTORS OF MODEL AIRCRAFT* MODEL ENGINES MODEL BOATS RADIO CONTROL SYSTEMS eMODELCARSI*MODELINGACCESSORIES INDOOR DEMONSTRATIONS STATIC DISPLAY COMPETITION IN MANY CATEGORIES OVERSEAS EXHIBITORS CORDIALL Y INVIJftI INTERNATIONAL MODELER SHOW BOX 127 COSTA MESA CA 92627 714 548-4700 banked turns stayed right put aileron response great full power no flutter visible engine leaned out little stayed rich Response hands pilot After few fly-bys time landing remembered Dean instructions recommended three-point flair out Thats way was real joy see No pattern flying yet need training checkout time see no reason expect best airplane Besides week late story deadline See ya around next adventure We-Fly Lab Safety Preston continued page 70 kind requirement since plastic spinners 2apable going over 12000 rpm Perryported Supertigre 60 does 12900 add pipe will go 14000 must go metal spinner Weve no problem plastic rpm metal limit 18000 Are nylon ducted fan units hitting 22500 Youridea using 4-way wrench also over-cautious darn aluminum nuts will strip threads use too much force loosening problem 4-way turned down snugly change humidity say tighten time fire up Nobody does am modeler does like way protecting legal hide expense modeler Offer realistic instructions Ive no doubt will readers will feel letter-writer has point too will probably ignore safety precautions included modeling products Its yourhide trying protect Unfortu nately have accident chances will seeking help others Lets spoil pleasure because carelessness As write second column safety still some two months away publica tion first column Nevertheless Im already getting lot feedback accidents happening fellow modelers through club newsletters mailed AMA Head quarters far common reported incidents involving lacerations pro pellers example engine started rpm much higher expected able hold alrplane prop struck him left arm above elbow prop cut brachial artery median nerve muscle nicked bone before breaking newsletter article goes say arm now cast control movement until heals thumb first two fingers numb tingle have limited mobility present think would agree small change past operating procedures might well worthwhile avoid type injury particular case engine apparently inadvertently started high throttle un expected burst power could handled victim Editor always start engines half-throttleor less will start way finish months sermon have tip comes Jerry Gotts writing DCRC newsletter Jerry clubs safety director happens safety-conscious modelers know Which just goes show us immune accidents Jerry recently have stitches close lacerations three fingers caused contact black glassfilled resin prop props almost totally invisible running engine Jerry suggests prop tips painted white visibility also offers 10 other safety tips regarding pro pellers reproduce benefit 1 Tighten prop nut least beginning flying day 2 Position radio side front prop wont have reach behind prop operate radio sure radio throttle control operating 3 Start engine low throttlenot wide open 4 Keep face away rotating plane prop 5 Use chicken stick electric starter 6 Take extreme caution glow plug wire also removing same engine 7 Examine props often cracks chips balance 8 Give meat grinder wide berth respect commands 9 Always keep uppermost conscious mind spacial relationship hands body spinning prop aware what prop blast may doing others Think about engine thrust might move pivot plane should slip get away 10 Move slowly deliberately think think think. think would add other item Jerrys list needle valve tweaking throttle twiddling behind prop Have safe month John Preston 7012 Elvira Ct Falls Church VA 22042 126 Model Aviation