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Old 10-16-2011
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jackdale jackdale is offline
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Theoretical hull speed of a displacement hull= 1.34 X sqrt LWL

Other factors -

1) planing will take you above theoretical hull speed, usually downwind with a chute of some sort.

2) fouled bottom will slow you down.

You need a knotmeter, not a GPS when dealing with hull speed as it is through the water not over the ground. In addition you want a momentary speed not an average.
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