[PCW] Fwd: Power-Catamaran post from preischmann at msn.com requires approval

[Georgs Kolesnikovs]

From: "Pat Reischmann" <preischmann at msn.com>
To: <power-catamaran at lists.samurai.com>
Subject: Re: Power-Catamaran Digest, Vol 47, Issue 7
Date: Sun, 8 Mar 2009 11:31:28 -0400


Bob, ground effect and air cushion refer to two different things. Ground
effect is lift, air cushion is just that, air trapped in the tunnel
consequently improving ride in a seaway.  The Kutta effect refers to a first
slowing down of air in the venturi if you will and then a rapid speeding up at
the exit, this intern causes for an increase in velocity over the top to match
the velocity at the exit under, thus creating circulation and enhancing lift.
I have often thought this may be the case with high speed cats even though it
is used to explain sail efficiency. In racing hydro's and cats I am sure the
deck design  can create a foil wing that provides lift like an aircraft.a