Chart Navigation & Plotting · Dead Reckoning — Rules
In U.S. practice, a DR position should be plotted at each of the following EXCEPT:
- AEvery course change
- BEvery speed change
- CEvery fix or running fix
- DEvery time the wind shifts✓ Correct
Explanation
DR is advanced at every course change, every speed change, at every fix/running fix, and at least every hour on the hour. Wind shifts are not a DR rule (their effect is leeway, applied when estimating position).
Authority: Bowditch (Pub. No. 9), DR plotting rules
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