"Martin Baxter" wrote in message
...
Bob Crantz wrote:



The Flettner "trim tab" improves stall characteristics of the rudder.

That may be true, but if you have to push the rudder to one side to
"balance" the boat, (doesn't drag increase with angle of attack?), then
you're going to increase drag.

It's the L/D ratio. If L increases faster than D the rudder is more
effective.



Better to trim the boat properly with
the sails and not have to shove bucket loads of water around.

This is only true if the boat sails in a straight line down its centerline.



Cheers
Marty
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