Chart Navigation & Plotting · Fixes — Distance by Two Bearings and Run
When advancing an LOP for a running fix, the line is moved:
- AToward the observed object by the change in bearing
- BPerpendicular to itself by the distance run
- CParallel to itself, in the direction of the course made good, by the distance run✓ Correct
- DIt is rotated about the landmark by the course change
Explanation
To advance an LOP, translate it parallel to itself in the direction of the course made good through a distance equal to the run between observations. If a current is known, advance for the course and distance over the ground (set and drift applied).
Authority: Bowditch (Pub. No. 9), Advancing a Line of Position
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