Navigation General · Currents
In the current triangle, which vector represents the vessel's motion relative to the seabed?
- AThe water track vector (ship's heading and speed through water)
- BThe current vector (set and drift)
- CThe reciprocal bearing of the set
- DThe ground track vector (CMG and SMG)✓ Correct
Explanation
The ground track vector represents the resultant of the vessel's motion through the water plus the current's effect, giving Course Made Good (CMG) and Speed Made Good (SMG) — the actual motion over the seabed.
Authority: Bowditch (Pub. 9), Ch. 7
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