Chart Navigation & Plotting · Fixes — Quality / Two LOPs
Two lines of position give the strongest fix when they intersect at an angle near:
- A90°✓ Correct
- B15°
- C170°
- D5°
Explanation
A 90° cut minimizes the error ellipse, so two LOPs crossing near right angles give the best-defined fix. LOPs that are nearly parallel (small or near-180° cut) make position uncertain along the lines.
Authority: Bowditch (Pub. No. 9), Quality of a Fix
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