ORIGINAL: spidr_01
I have a tower trainner 40, and I put a O.S. 46 AX in it. The manual recommends a 10.5X6, 11X6-8, 12X6-7 size prop. I have a 11X6 on it now and my club trainner would like to slow it down. any recomendations on how to do it without buying a new engine? he recomended a 11X5 prop and thought a longer prop may not be very good for the engine. Oh, the O.S. manual has the props listed as sport and dosent list any other recomendations.
all recomendations are appriceated and will be tryed, thank you.
An 11-4 will help. However, an 11-4 is light for a .40 and a .46 AX is overkill. You are going to be turning MORE RPM, Tell your instructor that the throttle does NOT have to be full forward regardless of the fact that he can push it there.
With a Tower trainer 40, a good .29 will fly it well. A .46 AX is real overkill. Simply throttle back to a comfortable cruise speed and work from there.