Chart Navigation & Plotting · Set & Drift — Computing Current
A 1300 fix lies 3.0 nm at 090° from the 1300 DR position. The set and drift of the current experienced since the last fix at 1100 are:
- ASet 270°, drift 1.5 kn
- BSet 180°, drift 1.5 kn
- CSet 090°, drift 3.0 kn
- DSet 090°, drift 1.5 kn✓ Correct
Explanation
The vessel was set from DR to fix in the direction 090° (the set). Over 2 hours the displacement was 3.0 nm, so drift = 3.0 ÷ 2 = 1.5 knots. Set is the direction toward which the vessel was carried.
Authority: Bowditch (Pub. No. 9), determining current
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