[PCW] Air cushion between catamaran hulls

[Robert Deering]

Georgs, I agree with you.  I sure miss Malcolm's analytical explanations of
catamaran dynamics.  This is an issue that needs more factual analysis and
less subjective claims by boat marketers.

Henry, I'm not saying there is zero cushioning effect from the air in the
tunnel, but I do believe that it is negligible with the boats, and at the
speeds we're talking about.  I suspect that your experience with the ride
improving has more to do with the boat transitioning to a semi-planing
condition and the hull rising higher above the waves.  I experienced that
effect often in my planing catamaran - often the best ride was above 30 kts.

Sealubber, for the cruising/recreational catamarans we're talking about here
I doubt that air injection would help much.  Most  planing cats have limited
planing surface area as compared to a monohull, so injecting air would tend
to worsen that situation, making it harder to stay on step.  The
displacement cats aren't running so fast that air injection would seem to
offer much performance advantage.  A racing hull is a different story, and I
would expect that air injection is used where it provides an advantage.