Third number in prop size??
03-09-2006 | 01:29 PM
#1
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From: Kennewick,
WA
Third number in prop size??
Trying to find an 18x10 prop at the LHS, they had an 18x8x4.
I've seen this on some other props, what does the third number mean?
I've seen this on some other props, what does the third number mean?
03-09-2006 | 01:55 PM
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From: Bakersfield,
CA
RE: Third number in prop size??
If it's a 18x8-4, it means 18" diameter and the pitch (angle of blades) progresses (regresses?) from 8 at the hub to 4 at the tips.
03-09-2006 | 02:29 PM
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From: Halifax,
NS, CANADA
RE: Third number in prop size??
I don't think they make such a thing as a 18 - 8 - 4 I think you'll find it is a 18 - 8 - 14. Some engines respond very well to these multi pitch props, the old Quadra's were one of those engines.
03-09-2006 | 04:27 PM
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RE: Third number in prop size??
Different bits of the prop work well at different RPM's & different airspeeds. There is always some portion of the prop that is doing it's thing fairly well at any one time. They are the ultimate compromise -- they don't do anything particularly well, but they don't do anything particularly badly either. The all-season tires of propdom.
