USCG Exam PracticeVisual piloting — three-bearing fixes, danger bearings
You take a bearing of 270°T on a charted buoy and note the time. Fifteen minutes later you take a second bearing of 225°T on the same buoy. You advance the first LOP along your DR track to the time of the second bearing. The result is BEST described as:
- A. A fix, because two LOPs from the same object were used
- B. A danger bearing, because the bearing has changed more than 45 degrees
- ✓ A running fix, less accurate than a fix from simultaneous LOPsCorrect
- D. A dead reckoning position, because only one object was observed
Why C is correct
Bowditch Ch. 7 §702 defines a running fix as one obtained when LOPs cannot be taken simultaneously, with the first LOP advanced along the DR track. It is explicitly noted as less accurate than a simultaneous fix. Using a single object with two time-separated bearings is the classic running fix scenario.
Cited:Bowditch Ch. 7 §702