CONTROL LINE SPEED uri r1iu ux mu m1TIJ-l u Ii 1 JETS Just word exciting impresses sense speed daring wonder spectators come Nats simply watch noisiest event Jet Speed seem enjoy magnificent roar produced firesticksas response primeval urge latent remembrance fire-breathing dragons write about pulse jetsminiature models engine powered infamous German Vi flying bomb used destructively World War II Unlike turbo jets rapidly spinning rotors pumps other complicated machinery pulse jets have moving part reed valve opens closes time engine fires different pulse jet designs have built some no valves ones used Jet Speed however reed-valve type pulse jet has multiport head reed valve valve retainer combustion chamber extended tailpipe fuel metering jet spark plug initial ignition Refer Dynajet Figure head machined solid aluminum threads combustion chamber two /s-16 threads narrow threaded locking ring clamps two together intake 15A6 diameter Dynajet forms venturi blends ten 11A2-diameter ports angle outward 200 venturi creates enough vacuum air rushing through draw fuel through metering jet eliminating need pressurized fuel system average positive pressure combustion chamber jet running pressure can used positive fuel feed usually necessary new head utilizes larger intake different-shaped intake does draw fuel reed valve made spring steel high-strength heattreated stainless steel-usually 006 007 thick clamped rear face head curved aluminum valve retainer valve retainer prevents reed petals opening too far importantly keeps movements synchronous hop-up procedure Dynajet modify valve retainer allow reed open farther taking much 080 off retainer maintaining proper curve combustion chamber tailpipe made stretch-forming two halves out 010-inch type 321 stainless steel butt-welding together Heli-arc welding used now original Dynajets flame-welded oxyacetylene torch filler wire few tailpipes made out inconel increase heat resistance material cost too high threaded ring screws pipe head brass pulse jet reed valve opens closes letting fuel air combustion chamberabout 220-240 times second 30 ax CORNER DETAIL r-illJ-1 Iii 250 DIA PIN 0 252 REAM K ~1 II LOCKNUT 5/16x18 STOP STUD FIGURE 2 Valve cupper bends reed valve petals presses valve against head creating seal can metal silver-soldered combustion chamber Early Dynajets large automotive spark plug mounted near throat just ahead combustion chamber-tailpipe junction soon moved September 1994 113 REED VALVE JET PORTS1O FIGURE 1 Mike Couts record-setting jet custom-built head stock Dynajet Jerry Thomas jet has augmentor tube increased thrust pipe Daughter Jennifer holds monoline trainer testing necessary definitive results * gqA4W 1994 United States Control Line Team preparing World Championships held Shanghai China October can part effort financial support following Official Team Apparel Souvenir items offered fund raisers TEAM JACKET Red 100% Satin Nylon Lined Raglan Sleeves USA block letters back American Flag shoulder Team Patch left chest Small Medium Large X-Large XX-Large$8000 TEAM GOLF SHIRT White Heavy weight 50/50 Cotton/Polyester small Team Logo Silk Screened left chest SMLX-L $2000 -L $2200 TEAM T-SHIRT White Heavyweight 100% Cotton large Team Logo chest MLX-LXX-L $1000 TEAM BASEBALL CAP Blue Adjust able Team Patch 000 TEAM PATCH 100 Embroidered Red White Blue 400 TEAM PIN Hard Cloisonne Logo Red Blue Chrome 00 Please add $500 Shipping Packing orders over $8000 Send Check Money Order WALT PERKINS 4416 SE 4 PLACE OCALA FL 34471 Funds Benefit 1994 United States Control Line Team Members THE UNITED STATES CONTROL LINE TEAM WELCOMES INDUSTRY SUPPORT AS WELL INTERESTED CONCERNS PLEASE WRITE TO WALT PERKINS AT THE ABOVE ADDRESS members 1994 United States Control Line Team would like take opportunity thank Orange Blossom Hobbies Sig Manufacturing Precision Model Products Tru-Turn generous involvement years program CAMPBELL TOOLS CO 210GM SeIma Road Spiingfleld OH 45505 513 3228562 800 number orders Catalog $100 forward replaced smaller modelairplane-type spark plug Operation simple turn continuous spark inject charge fuel air combustion chamber explodes explosion forces flapper valve shut ejects exhaust gases out tailpipe gases have appreciable mass forced out high velocity resulting net forward thrust After explosion pressure pulse collapses fresh air rushes back combustion chamber both endsfrom intake tailpipe Since tailpipe long incoming charge fresh air intake has opened reed valves rushed combustion chamber along fuel picked up venturi fresh charge fuel air meets remaining hot exhaust gases another explosion occurs repeating sequence sequence happens 220 240 times second explosions produce about 4/2 pounds static thrust stock Dynajet burning white gas volumes theoretical calculations have written about pulse jets must built work Im sure anyone positively knows what happens system must synchronous work must have correct chamber diameter chamber length tailpipe diameter tailpipe length proper operation dimensions change size engine Vi engine short fat small OS Tiger Jet long skinny Dynajet hose fitting fuel flowjector attach tire pump starting Pumping too much work modelers now use pressurized air tank scuba tank regulators staffing air Just squirt shot prime fuel intake turn spark give short blasts air intake until starts spark supplied Model T Ford spark coilstill available special auto supply housesor other vibrator-type spark supply Several modelers have written questioning toxicity alcoholpropylene oxide fuel Controlled tests indicated massive doses propylene oxide seemed carcinogenic cancer producing animals results really conclusive effect humans has really determined dangerous methanol other hydrocarbonseven gasoline Propylene oxide seems able penetrate skin enter bloodstream take precaution prevent contact filling fuel tank mixing fuel attitude used such things drying fruit sterilizing packaged food cant too bad Im still careful however keep cool ice-filled picnic cooler contests highly flammable explosive careful keep away possible source fire sparks used have trouble getting jet started think trouble reed did not seal tightly against head Earl Bailey gave dimensions valve cupper see Figure 2 device bends petal reed presses against head after valve retainer tightened Adjust stop screw until least 030 cupping valve face head must smooth flat course lap head glass plate using various grits fine sandpaper oil usually start 280 grit end up 400 600 always lapping figure-eight motion sure reed aligned cover ports correctly Seal head threads teflon plumbing tape Ill continue jets discussion next column 4COMET LING ELAND 1CToR STANZEL EST ER LORAFT z OU SPEAK MODEL AIRPLANE Dave Thornburgs concise history US aeromodeling heroes models 4 famous contestsfrom first twin pusher ________the ugliest Stik youve hobby 1 25 years lIfe 316 pages $1995 dealer postpaid cash check V/MC Pony X Press 5 Monticello DrIve Albuquerque NM 87123 505 299-8749 8 Also available Thornburgs OLD BUZZARDS SOARING BOOK $1695 pp BAY RIDGE NTIFIC LESS L ICAN JUNIOR CYCLONE GRAM T PLANES 114 Model Aviation hi Large Sheets Please call 509-548-5201 send SASE 12306 Bergstrasse Leavenworth WA 98826
Edition: Model Aviation - 1994/09
Page Numbers: 113, 114
CONTROL LINE SPEED uri r1iu ux mu m1TIJ-l u Ii 1 JETS Just word exciting impresses sense speed daring wonder spectators come Nats simply watch noisiest event Jet Speed seem enjoy magnificent roar produced firesticksas response primeval urge latent remembrance fire-breathing dragons write about pulse jetsminiature models engine powered infamous German Vi flying bomb used destructively World War II Unlike turbo jets rapidly spinning rotors pumps other complicated machinery pulse jets have moving part reed valve opens closes time engine fires different pulse jet designs have built some no valves ones used Jet Speed however reed-valve type pulse jet has multiport head reed valve valve retainer combustion chamber extended tailpipe fuel metering jet spark plug initial ignition Refer Dynajet Figure head machined solid aluminum threads combustion chamber two /s-16 threads narrow threaded locking ring clamps two together intake 15A6 diameter Dynajet forms venturi blends ten 11A2-diameter ports angle outward 200 venturi creates enough vacuum air rushing through draw fuel through metering jet eliminating need pressurized fuel system average positive pressure combustion chamber jet running pressure can used positive fuel feed usually necessary new head utilizes larger intake different-shaped intake does draw fuel reed valve made spring steel high-strength heattreated stainless steel-usually 006 007 thick clamped rear face head curved aluminum valve retainer valve retainer prevents reed petals opening too far importantly keeps movements synchronous hop-up procedure Dynajet modify valve retainer allow reed open farther taking much 080 off retainer maintaining proper curve combustion chamber tailpipe made stretch-forming two halves out 010-inch type 321 stainless steel butt-welding together Heli-arc welding used now original Dynajets flame-welded oxyacetylene torch filler wire few tailpipes made out inconel increase heat resistance material cost too high threaded ring screws pipe head brass pulse jet reed valve opens closes letting fuel air combustion chamberabout 220-240 times second 30 ax CORNER DETAIL r-illJ-1 Iii 250 DIA PIN 0 252 REAM K ~1 II LOCKNUT 5/16x18 STOP STUD FIGURE 2 Valve cupper bends reed valve petals presses valve against head creating seal can metal silver-soldered combustion chamber Early Dynajets large automotive spark plug mounted near throat just ahead combustion chamber-tailpipe junction soon moved September 1994 113 REED VALVE JET PORTS1O FIGURE 1 Mike Couts record-setting jet custom-built head stock Dynajet Jerry Thomas jet has augmentor tube increased thrust pipe Daughter Jennifer holds monoline trainer testing necessary definitive results * gqA4W 1994 United States Control Line Team preparing World Championships held Shanghai China October can part effort financial support following Official Team Apparel Souvenir items offered fund raisers TEAM JACKET Red 100% Satin Nylon Lined Raglan Sleeves USA block letters back American Flag shoulder Team Patch left chest Small Medium Large X-Large XX-Large$8000 TEAM GOLF SHIRT White Heavy weight 50/50 Cotton/Polyester small Team Logo Silk Screened left chest SMLX-L $2000 -L $2200 TEAM T-SHIRT White Heavyweight 100% Cotton large Team Logo chest MLX-LXX-L $1000 TEAM BASEBALL CAP Blue Adjust able Team Patch 000 TEAM PATCH 100 Embroidered Red White Blue 400 TEAM PIN Hard Cloisonne Logo Red Blue Chrome 00 Please add $500 Shipping Packing orders over $8000 Send Check Money Order WALT PERKINS 4416 SE 4 PLACE OCALA FL 34471 Funds Benefit 1994 United States Control Line Team Members THE UNITED STATES CONTROL LINE TEAM WELCOMES INDUSTRY SUPPORT AS WELL INTERESTED CONCERNS PLEASE WRITE TO WALT PERKINS AT THE ABOVE ADDRESS members 1994 United States Control Line Team would like take opportunity thank Orange Blossom Hobbies Sig Manufacturing Precision Model Products Tru-Turn generous involvement years program CAMPBELL TOOLS CO 210GM SeIma Road Spiingfleld OH 45505 513 3228562 800 number orders Catalog $100 forward replaced smaller modelairplane-type spark plug Operation simple turn continuous spark inject charge fuel air combustion chamber explodes explosion forces flapper valve shut ejects exhaust gases out tailpipe gases have appreciable mass forced out high velocity resulting net forward thrust After explosion pressure pulse collapses fresh air rushes back combustion chamber both endsfrom intake tailpipe Since tailpipe long incoming charge fresh air intake has opened reed valves rushed combustion chamber along fuel picked up venturi fresh charge fuel air meets remaining hot exhaust gases another explosion occurs repeating sequence sequence happens 220 240 times second explosions produce about 4/2 pounds static thrust stock Dynajet burning white gas volumes theoretical calculations have written about pulse jets must built work Im sure anyone positively knows what happens system must synchronous work must have correct chamber diameter chamber length tailpipe diameter tailpipe length proper operation dimensions change size engine Vi engine short fat small OS Tiger Jet long skinny Dynajet hose fitting fuel flowjector attach tire pump starting Pumping too much work modelers now use pressurized air tank scuba tank regulators staffing air Just squirt shot prime fuel intake turn spark give short blasts air intake until starts spark supplied Model T Ford spark coilstill available special auto supply housesor other vibrator-type spark supply Several modelers have written questioning toxicity alcoholpropylene oxide fuel Controlled tests indicated massive doses propylene oxide seemed carcinogenic cancer producing animals results really conclusive effect humans has really determined dangerous methanol other hydrocarbonseven gasoline Propylene oxide seems able penetrate skin enter bloodstream take precaution prevent contact filling fuel tank mixing fuel attitude used such things drying fruit sterilizing packaged food cant too bad Im still careful however keep cool ice-filled picnic cooler contests highly flammable explosive careful keep away possible source fire sparks used have trouble getting jet started think trouble reed did not seal tightly against head Earl Bailey gave dimensions valve cupper see Figure 2 device bends petal reed presses against head after valve retainer tightened Adjust stop screw until least 030 cupping valve face head must smooth flat course lap head glass plate using various grits fine sandpaper oil usually start 280 grit end up 400 600 always lapping figure-eight motion sure reed aligned cover ports correctly Seal head threads teflon plumbing tape Ill continue jets discussion next column 4COMET LING ELAND 1CToR STANZEL EST ER LORAFT z OU SPEAK MODEL AIRPLANE Dave Thornburgs concise history US aeromodeling heroes models 4 famous contestsfrom first twin pusher ________the ugliest Stik youve hobby 1 25 years lIfe 316 pages $1995 dealer postpaid cash check V/MC Pony X Press 5 Monticello DrIve Albuquerque NM 87123 505 299-8749 8 Also available Thornburgs OLD BUZZARDS SOARING BOOK $1695 pp BAY RIDGE NTIFIC LESS L ICAN JUNIOR CYCLONE GRAM T PLANES 114 Model Aviation hi Large Sheets Please call 509-548-5201 send SASE 12306 Bergstrasse Leavenworth WA 98826