Many, many ways and times.

There is a book about sailing physics by C.A. Marchaj. (I hope I got the
author's name right.) It will have enough information about sailing
physics to satisfy even a graduate level physics person.
good luck and have fun sailing.

Mike wrote:
In books about sailing, I have read that the keel, going through water,
produces lift in a similar way to a sail. Given that water is a
non-compressible medium, I wonder how this can be so. Has it ever been
documented?


--
Michael Hobbs
Minneapolis, Minnesota