Nomograph for Propeller Design his chart is more complicated T than the graphs published pre-
By Raoul J. Hoffman...reprintedfrom March. 1936 Popular Aviation, rw/r/esv Flying Mnfyizine. BROKE HORSEPOWER
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will get the developed blade of the propeller. This is not only of value to lightplane builders, but it also will be of assistance to that new group of flight enthusiasts who are now building gas-power models. Only slight modifications are necessary for the gas models. This chart is third in a series of charts. A
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viously. This will design your propeller by carefully following the example worked out on the lower end of the nomograph. It will help you find the diameter required, the maximum efficiency available, the pitch-diameter ratio from which you may figure the geometrical pitch necessary to lay out your propeller. Multiplying the constants given in the sketch by the diameter you
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It is with regret that we were notified of the untimely death of
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EXflHPLE 50 BHP.IBOD RPM .80 MILE5 P HOUR 3PEEP PROPELLER COMMECT 6D DM SCflLE n« ' UITH 1800 00 3CflLEM*2 IMTER SECTIMD REFERENCE LIME N'3. THEH PDim DM REFLinE WITH 80 Oh 5CflLE n*'*.THEM TOUUJLLFinD THE LinEPfl55inG THRU 7 Ft OH 5CflLE M'S. WHICH 15 THE PlflMETER THEfl COMMECT lOOO DM 3CHLE M»Z UITH 80 0(1 SCflLE f1"t THOU 3 9 01 SCflLE H'B THEM 39 Oh 5CflLE M«B WITH 7 On 5CRLE tl'5 IMTERSCCTinQ SCflLE H'- 7 flT BS 7FT TIME5
63 EQUflLS 53 IMCHES GEOMETRICHL P I T C H , . 7 1 EFFICIEnCIf
16
one of our most enthusiastic members. Marshall R. Sherrill, Jr., 21, of Maitland, Fla., EAA member 721, lost his life October 10 as a result of a parachute failure during a college jumping event. The main chute failed to open and the emergency chute opened only a few feet above the ground. Many of you who have attended our annual FlyIns undoubtedly have met Marshall, as he attended all five events. The December, 1956 issue of the EXPERIMENTER carried a photo of Marshall and his partially completed Playboy. His father advises us that he would like to dispose of the Playboy which contains the fuselage and tail group - zinc chromated, landing gear, wheels, wing ribs, spars, plans, plus many fittings and other parts. Marshall R. Sherrill, Sr. is interested in seeing some appreciative person obtain it and can be reached at Rt. 2, Box 29, Maitland, Fla. A JANUARY
1958