Celestial Navigation · Fix — Symmetry of Three LOPs
If three star LOPs form a small triangle, the navigator should:
- ATake the position near the center, and check for a constant error if the triangle is large✓ Correct
- BDiscard all three sights
- CUse only the longest LOP
- DAssume the position is at one vertex
Explanation
A small triangle ('cocked hat') from three star LOPs indicates a good fix near its center. A large triangle suggests a systematic error (e.g., bad time, index error, or a wrong assumed position) common to the sights, which should be found and corrected.
Authority: Bowditch (Pub. No. 9), Fix Quality
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