Navigation General · Set & Drift
Over a 4-hour run, a vessel was set 8 nm in the direction 045°T from its DR position. What is the drift of the current?
- A1.0 knot
- B2.0 knots✓ Correct
- C4.0 knots
- D32.0 knots
Explanation
Drift = total displacement / time = 8 nm / 4 hr = 2.0 knots. Drift is the speed of the current, expressed in knots.
Authority: Bowditch (Pub. 9), Ch. 7
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