Navigation General · Piloting & Bearings
Which geometric arrangement of three simultaneous LOPs gives the most reliable three-bearing fix?
- AAll three bearings within 30° of each other
- BBearings approximately 60° apart
- CTwo parallel bearings and one crossing them at 90°
- DBearings approximately 120° apart✓ Correct
Explanation
Three LOPs approximately 120° apart (cutting at 60° angles to each other) produce the best geometry, minimizing the cocked hat triangle error. LOPs that are nearly parallel greatly amplify position errors.
Authority: Bowditch (Pub. 9), Ch. 8
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