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Leeway Angle

Approximate leeway angle from the beam-wind component and ship speed, using the rule of thumb: leeway (°) = wind speed / ship speed × f.

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Formula, assumptions, and limits

LeewayfVwindsinθVship\text{Leeway}^\circ \approx f \cdot \frac{V_\text{wind} \cdot |\sin\theta|}{V_\text{ship}}
SymbolMeaningUnit
VwindV_\text{wind}True wind speedkn
θθWind angle off bow°
VshipV_\text{ship}Speed through waterkn
ffEmpirical hull factor

Source: Bowditch - American Practical Navigator

In short

Approximate leeway angle from the beam-wind component and ship speed, using the rule of thumb: leeway (\u00b0) = wind speed / ship speed \u00d7 f.

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