Speed difference between propellers

[therobesons]

I know that a good folding prop will give you the least drag there for the most speed and a 3 or 4 blade the most drag with less speed (while sailing)

My question is:

Under normal sailing conditions, wind 10-15, how much of a difference is there?

Are we talking 2 knots, 1 knot or is it hardly noticeable.

I did one nice sail to Catalina Island and back, my boat has a 3 blade fixed prop and we were over 6 knots most the time and saw 7 a few times in 12-15 knot winds.

I know that drag goes up expotincially so I would think we would hit hull speed limits before we saw much difference in drag at around 6-7 knots.

Any thoughts?

Thanks

Bob

[cillman]

I know that a good folding prop will give you the least drag there for the most speed and a 3 or 4 blade the most drag with less speed (while sailing)

My question is:

Under normal sailing conditions, wind 10-15, how much of a difference is there?

Are we talking 2 knots, 1 knot or is it hardly noticeable.

I did one nice sail to Catalina Island and back, my boat has a 3 blade fixed prop and we were over 6 knots most the time and saw 7 a few times in 12-15 knot winds.

I know that drag goes up expotincially so I would think we would hit hull speed limits before we saw much difference in drag at around 6-7 knots.

Any thoughts?

Thanks

Bob

Bob - based on eleven months with a Kiwi feathering prop, I see about a half knot extra boat speed in five knots of wind and the improvement diminishes as you approach hull speed.

Craig

[therobesons]

I had a folding prop on my last c36 (1986) and we have a 3 blade on this one.

Since we can sail at 6plus even into the 7's as is, I think we will stay with our 3 blade prop as I do like the smooth motoring perforance we have.

Bob