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Old 03-30-2014, 01:43 PM   #5
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Join Date: Oct 2007
Posts: 21,353
>Hull speed is a theoretical and practical concept. Theoretically it is 1.34 * sqrt(LWL)<

This is ONLY for fat boats 3x or 4x as long as they are wide.

Once you get into long and skinny , cat or try hulls that speed formula does not work.

Years ago the AYRS came up with a simple method of figuring "hull" speed for a variety of boats.
The old formula was created by looking at fat boats of the 1800 rea , and doesn't work well for skinny fast boats.

S = L/3b X SQRT (L) When run for some theoretical hulls it may be a bit fast , but seems to work.

Practically a 6-1 LB ratio gets the job done on a heavy boat , 8-1 to 16-1 do better as the weight decreases.

Your boat is a go fast ,created to plane underway.

Its ride comfort and much stability come from being ON the top of the water.

Sure it eats fuel, but what is currency for?
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