Navigation General · Piloting
Two ranges (each formed by two charted objects in line) observed simultaneously give a fix that is:
- AUnreliable because ranges drift
- BOnly valid at night
- CUseful only for depth
- DVery accurate, since each range is a precise LOP with no instrument bearing error✓ Correct
Explanation
When two charted objects are in line they define an exact LOP requiring no compass bearing, so two such ranges crossing at a good angle give one of the most accurate fixes available in piloting waters.
Authority: Bowditch (Pub. 9); piloting
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