Since the P-15's flotation is in the bottom of the boat, If you admit water
THROUGH the bottom the boat will reach an equilibrium state with the bare
minimum of water aboard.
If the boat is capsized on it's side and is taking on water, the flotation
becomes effective gradually since it has to be immersed to be useful. Picture a
Potter laying on it's side, half full of water. Only half of the boat's
flotation is in use and therefore more water is free to enter. When the boat is
turned back upright it is like a bowl full of water All of the floation can be
effective now and I'm going to guess that it will lift the boat until the top of
the centerboard trunk is at water level (water is free to move from inside the
boat to the outside through the centerboard trunk). The remaining water is
trapped and the boat will float at this level. In a P-15, this would put the
water level about even with the cockpit seats and bridgedeck which, I think, is
about what the folks who have had this misfortune have described. It's
thoroughly swamped.
With a turtled boat, the situation is even worse. When the boat is upside down,
the floatation is at the very top of the inverted boat. Water rushes in through
the companionway (almost instantly if it's open) and the vent in the anchor
locker. The amount of water that can end up inside the boat in this
configuration is formidable, right? Once the boat is righted, I'd expect that
not much boat is showing. Since the water pressure difference across the the
centerboard slot is small, flow will be very slow but I will speculate that over
a period of several hours (days?) the boat would eventually rise to the same
point as decribed in the previous paragraph, with the top of the cb trunk at the
waterline.
All of this is open to critique, since I've no facts or calculation to back it
up. I'd be interested in hearing the thoughts of others as well as how these
hypothetical situtations might transpose to the larger world of the P-19.
Dave Kautz
P-15 #1632 Tilly Lucy
Palo Alto, CA
______________________________ Reply Separator _________________________________
Subject: Re: picture in the brochure
Author: Non-HP-uffda (uffda@sonic.net) at hp-boise,mimegw7
Date: 5/12/99 7:56 PM
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West Wight Potter Website at URL
http://www.lesbois.com/wwpotter/
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>Maybe someone can explain this one: why do the pictures in the Potter
>brochure show the P-15 and P-19 floating so high and dry even though they
>have large holes drilled in the hull? It looks like the water wouldn't even
>be touching the flotation in the P-15. Is it possible to levitate the boat
>out of the water by drilling even bigger holes in the hull?
>
>Jim Nolan
>
Jim
I've also wondered about that. According to the reports on turtled boats
that I have read, the absolute floatation in a P-15 is just enough to keep
about three foot of the bottom of the bow above water. Maybe tests are in
order... anyone want to volunteer their boat?
Larry