Set & Drift - Current Triangle

Resolve set and drift of a current into along-track and across-track components for leeway compensation - the classical vector triangle.

CurrentSetDrift

Current set (°T toward)degDrift speedknShip COGdeg

Along-track component: 1.15kn

Across-track component: -0.96kn

Changing the inputs requires JavaScript. The calculator above shows its default inputs and result. The formula, symbols, and regulatory sources are shown in the Formula section below.

Formula, assumptions, and limits

v_{along} = D \cos(S - C), \quad v_{cross} = D \sin(S - C)

Symbol	Meaning	Unit
$S$	Current set (toward)	°T
$D$	Drift speed	kn
$C$	Course over ground	°T

Source: Bowditch Pub.9 Ch.7

In short

Resolve set and drift of a current into along-track and across-track components for leeway compensation - the classical vector triangle.

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