Marine Prop Slip

Theoretical speed, slip percent, and planing vs displacement category from RPM, gear, pitch, and GPS speed.

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Formula and source

Theoretical knots = (RPM / gear_ratio) × pitch_in / 1056. Slip % = (theoretical − actual) / theoretical × 100. Planing 10–15% / displacement 25–30% category bands.

Classical marine-propeller theory; ABYC P-17 (Boat Propeller Selection) by name.

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This tile is built for mechanics and the adjacent professions in the Mechanic - Auto, Marine, Aviation group. The interactive calculator runs entirely in your browser. No account, no fee, no advertising, no tracking.

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