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I suspect they would be different. To hazard a guess, a free spinning
prop is doing less work than a prop turning a motor, so it should
provide less drag. But a fixed pitch prop in either condition would want
to turn somewhere in the range of speed you would be gliding at. A prop
at flat pitch would need to speed up to a very high rpm to match the
forward speed of the plane. If the prop can't keep up with the forward
speed of the plane, it will effectively be pushing backward creating
extra drag. At least that's my armchair analysis. Bob White
On Sun, 19 Dec 2004 18:10:25 -0800 (PST)
Tom <tomtugan@yahoo.com> wrote:
I wonder if a free-spinning prop on a broken tranny would not have the
same drag as a spinning prop which is turning the motor? I'd be
inclined to say they would differ. Tom
--- Bob White <bob@bob-white.com> wrote:
> Somenone else recently reported a spinning prop having negligable
> effect on engine out glide. (Dave Leonard maybe?). I'm thinking
> that the biggest effect occurs with a C/S prop that goes to flat
> pitch when it looses oil pressure. I think twins often use
> feathering props for that reason.
> > Bob White
> > On Sun, 19 Dec 2004 15:41:53 -0500
> "Tracy Crook" <lors01@msn.com> wrote:
> > He glided about 20 miles from an altitude of only 5000 ft with the
> prop
> freewheeling! I've heard several times that a freewheeling prop
> (no engine drag on it) would generate lots of drag. Another sacred
> cow shot down : )
> > > > Tracy > > -- > http://www.bob-white.com
> N93BD - Rotary Powered BD-4 (soon)
> > >> Homepage: http://www.flyrotary.com/
> >> Archive: http://lancaironline.net/lists/flyrotary/List.html
>
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N93BD - Rotary Powered BD-4 (soon)
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