On 05/02/98 11:49:35 you wrote: > >Glenn Anderson wrote: >> >> You are probably right about the prop, I do have the E.ercoupe prop left >> over, it is a much nicer looking prop, maybe if I don't sell it soon I will >> put it on and try it >> Glenn > >Fred Weick was an especially good prop designer. He wrote "the" >textbook on propeller design. > >When Fred chose the propeller for the C-75 for the Coupe, he got >excellent performance. I haven't seen that much performance change when >upgrading to the C-85, largly I think, because of the less well >optomized propeller. > >Ideally, we would have variable pitch propellers so we could get flat >climb props for takeoff and coarse pitched cruise prop for straight and >level. > >I think the prop Fred picked for the C-75 is a pretty flat climb prop. >Then he let it spin fast in cruise. Not too much load then because the >prop isn't loading it too much. That doesn't optoimize your top speed >but it gets safer take-offs from a small engine. > >Top cruise speed is also limited by the shape of the boat. In boat >design, for each hull, there's a maximum speed which the hull can reach >with reasonable increase in power. But past that elbow, the liquid flow >over the hull piles up and doesn't flow well. Then the hull takes a LOT >of power to speed up a moderate amount extra. > >Airplanes are like that, too. I think the classic Coupe's max easy >speed is around 100-108 mph. Yeah, going to an O-200, 100 h.p. engine >will let you go faster, but not much faster. > >Ed Burkhead wrote: >How many people here are coming to Jacksonville, Ill., for the National >Fly-in? >
>From Springfield, Mo we have 2-4 coming that I know of. Myself and Cliff Lilly (not on the list--no computer) are planning to come; and I expect two other area coupers to go, although I haven't spoken with them. Don't know about the coupe in Bolivar Mo or the other coupe in Springfield. Ken Doyle Springfield, Mo Alon N5477E
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