Navigation General · Running Fix
A running fix is generally considered less reliable than a fix from simultaneous bearings because:
- AOnly one lighthouse can be used for a running fix
- BThe accuracy depends on the precision of the course and distance run between observations✓ Correct
- CRunning fixes cannot be plotted on Mercator charts
- DA running fix always results in a larger cocked hat
Explanation
A running fix requires advancing an earlier LOP, which depends on knowing the exact course made good and distance run between bearings. Any errors in CMG (from current, leeway, or compass error) or distance run will introduce error into the advanced LOP and the resulting fix.
Authority: Bowditch (Pub. 9), Ch. 8
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