Chart Navigation & Plotting · Aids to Navigation — Light Range
When the charted nominal range of a light exceeds the computed geographic range for your height of eye, the light will first be sighted at:
- AThe nominal range
- BThe geographic range (limited by the curvature of the earth)✓ Correct
- CTwice the nominal range
- DThe luminous range only
Explanation
If the light is bright enough to be seen beyond the horizon, the limiting factor is the geographic range (a function of the light's height and your height of eye). You see it when it rises above your visible horizon (its loom may appear first).
Authority: Bowditch (Pub. No. 9); Light List
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