Chart Navigation & Plotting · Fixes — LOP Definition
A single line of position from a visual bearing tells the navigator that the vessel is:
- AAt a known point
- BMaking a specific speed
- CAt the object observed
- DSomewhere along that line✓ Correct
Explanation
One LOP only establishes that the vessel lies somewhere on that line. A fix requires two or more LOPs crossing (ideally near 90°), or one LOP combined with a distance arc.
Authority: Bowditch (Pub. No. 9), lines of position
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