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> West Wight Potter Website at URL
> http://www.lesbois.com/wwpotter/
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> Anyone out there with experience on speed (or lack of) of P15's.
> In particular Mark ll's hull speed under sail with working jib? with genny?
> or power?
>
> Just curious.
> Jeff
> P15-"Blue Bayou"
>
According to Royce, the formula for hull speed for a displacement craft
(non-planing) is 1.34 times the square root of the waterline length (12 ft.
on the P-15). This gives a theoretical max speed of just over 4.6 kts./hr.
Lightweight boats can push this coefficient up to 1.5 or 1.6 which yields a
top speed between 5 and 5.5 knots/hr.. I think that this is in line with what
folks have measured via knotmeters and GPS. While it's not impossible to get
a P-15 to plane given favorable conditions, my experience is that it is only
momentary and the boat quickly returns to it's "trough". Perhaps a sailer
more skilled than I could get it to remain on plane longer.
Dave Kautz
P-15 #1632 Tilly Lucy
Palo Alto, CA