Chart Navigation & Plotting · Set and Drift
Your 0900 DR is 2.0 NM due north of your 0900 fix. Over the hour since the last fix, the current has:
- ASet you 2.0 NM north at a drift of 2.0 knots
- BSet you 2.0 NM south at a drift of 2.0 knots✓ Correct
- CHad no effect
- DSet you east at 2.0 knots
Explanation
Set is the direction from the DR to the fix; drift is the distance between them divided by the elapsed time. The fix lies 2.0 NM south of the DR, so the current set the vessel south (set 180°) at a drift of 2.0 knots over one hour.
Authority: Bowditch, American Practical Navigator (Pub. 9), current sailing
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