On Dec 3, 11:56*am, "Charles Momsen" wrote:
Why doesn't a keel achieve maximum efficiency with a leeway angle of 0
degrees?


Who says it doesn't?

I would say that a keel which makes ZERO leeway is highly efficient...
super-efficient.... preternaturally efficient!


What is a typical angle for maximum efficiency?


Depends on the typical aspect ratio and typical foil section.

Many boats make 3~5 degrees leeway when hard on the wind.


Does a catamaran have maximum efficiency at 0 degrees?


No of course not.

Why?

Because it's a catamaran, not an iceboat.

Fresh Breezes- Doug King