> I understand what you are saying about the wider prop wash, but I can't
> understand why it would be wider.


I do not know either. All I have been able to get in the line of an
official
answer from the prop mfgr was that the lower pitch props had a wider
propwash than the higher ones and that it was normal. He just couldn't
explain it to me plainly enough for me to understand why.... (sigh)

>Also, I can't understand why the 48" pitch
> prop would put out faster moving air than the 50" pitch prop.

It doesn't, What I am trying to say is that since propwash (regardless of
prop pitch) is higher speed air than the ambient air you are moving
through,
the 7148 spreads it out wider and exposes more of the plane to it. It
exposes enough of the plane to encompass the mains and nose gear and the
7150 doesn't. Put your hand out the window in a glide, hold it there and
go
full throttle. Even before the plane can accellerate your hand will feel a
significant drag increase since it is in the propwash. So does any other
part of the plane that is within the propwash. Look at the surface area of
your hand and then imagine the surface area of the gear. If I fly with my
7148 my gear is included in that additional drag because of the wider
"wake"
of the prop. If however I use my 7150 the gear flies through clean air
because it's "wake" is narrower. What made it notable enough for me to
share
it with the group was that even though the 48 was supposed to have better
climb than the 50 it didn't because it created enough additional drag on
my
gear, MLG lights, and inboard wing area to kill it's own advantage over
the
50.

Claude

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