Marine & Nautical

Intermediate

Hull Speed

Theoretical top displacement speed in knots from waterline length in feet.

Formula

v = 1.34\sqrt{L}

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Variables

vHull speed (knots)

LWaterline length (ft)

Example

L=36 ft: v = 1.34×6 ≈ 8.0 knots

Did You Know?

A displacement hull struggles to exceed its hull speed because it would have to climb its own bow wave.

marine hull speed boat

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