On Mon, 28 Jul 2003 17:03:39 -0400, John Cairns wrote:

No, disagree. I purchased a Gori folding prop this season after some
experimenting last season with the prop in neutral vs. reverse. The manual
that came with the boat recommends locking in reverse to prevent
transmission wear, shifting from reverse to neutral while under sail
resulted in a 1/2 increase in boat speed. Did this on several occasions,
just to verify. I figured a folding prop should be worth at least 1/2 knot
also.

Hmmm...
If the AOA is optimised for auto-rotation at a particular boat speed,
then a turning prop would indeed create less drag than a locked prop
up to that speed. At other boat speeds though, drag increases as
auto-rotation increases.
A locked and feathered prop creates the minimum amount of drag.

--
GW De Lacey