Navigation General · Running Fix
A vessel takes a bearing of 045°T on a lighthouse at 1000, then takes a second bearing of 000°T on the same lighthouse at 1030. The vessel made good 090°T at 12 knots between observations. The navigator uses this to obtain a:
- AFix
- BRunning fix✓ Correct
- CEstimated position
- DDR position
Explanation
A running fix is obtained by advancing an earlier LOP to the time of a later LOP. Since the two bearings were NOT simultaneous, the first LOP must be advanced along the vessel's course-and-distance-made-good before the LOPs can be crossed for a position.
Authority: Bowditch (Pub. 9), Ch. 8
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