Chart Navigation & Plotting · Set & Drift — Drift
Your fix lies 4.0 NM from your DR for the same time, and the last fix was 2 hours earlier. What is the drift?
- A0.5 knots
- B1.0 knot
- C4.0 knots
- D2.0 knots✓ Correct
Explanation
Drift = displacement ÷ elapsed time = 4.0 NM ÷ 2 h = 2.0 knots. Set would be the direction from the DR toward the fix.
Authority: Bowditch (Pub. No. 9), Current Sailing
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