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Tom Webb
 
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Default Heavy displacement vs Medium Displacement for Ocean Passages

"Paul L" wrote in message ...
What is the 'speed to length ratio"? Are you referring to square root of the
waterline?

Paul



Yes, the speed to length ratio is the speed of the boat divided by the
square root of it's sailing length. The units are feet and knots.
The ratio gives a feel for how fast a boat is when corrected for
length. A speed to length ratio of 1.34 is the speed of the wave that
has a length equal to the sailing length of the boat and is called the
"hull speed". Hull speed is a topic that has been discussed to death
on this board in the past, but you could google it if you really want
to know. Anyway, the speed/length ratio comes out in weird units
(feet per radical knots) so it has been replaced by the Froude number
in most new work...

Cheers,

-- Tom