USCG Exam PracticeThree-bearing fix and cocked-hat triangle
A fix obtained from two or more LOPs taken simultaneously is considered more accurate than a running fix primarily because:
- A. Simultaneous LOPs require no knowledge of the vessel's speed
- ✓ A running fix introduces error from advancing the first LOP along an estimated DR trackCorrect
- C. Simultaneous LOPs are always taken from fixed aids such as daybeacons
- D. A running fix can only be obtained using radar range and bearing
Why B is correct
A running fix advances the first LOP along the DR track to the time of the second observation. Any error in the estimated course or speed over that interval degrades the result, making it less accurate than a fix from simultaneous LOPs. Bowditch Ch. 7 §702.
Cited:Bowditch Ch. 7 §702