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Capt. Rob Capt. Rob is offline
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First recorded activity by BoatBanter: Jul 2006
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Default The Irony of the Doug -The Return!



In other words, they don't make the boat faster by lifting
the boat up? Is that your final answer?


In spite of Thom's assertions, drag wins the day. You can't get lift
without the cost of drag and a 35s5 is unable to gain enough velocity
to use such a wing to lift the hull. The 35s5 semi-planes based on the
hull form factor, not the wing. So the final answer is essentially NO.
Any effort to raise the boat my inducing lift on a dead run would be
made useless by lack of velocity combined with drag.

Are you sure? "to reduce the plate effect" is generally not
a design goal of any foil... otherwise why put an end plate,
in the form a wing, on it in the first place?


The wing on the 35s5 is a compromise and it costs performance in most
situations. The plate effect is one of those costs and efforts to
minimize the plate turbulence is certainly a design goal...one of many
for a wing keel.

You're saying that your keel is different on different tacks?


It behaves very differently on different tacks because forces are
distributed differently all the time. Say that 4 times fast!


Gee Bubbles, I'm surprised with all your advanced knowledge,
you haven't been tapped to serve as a design consultant on
one of those mega-buck racing yacht designs.


I only recently (last few months) started learning about keel design.
I'm slowly getting it.


RB
35s5
NY