Using a single charted object of known height to clear a hazard at a fixed minimum distance, you set a vertical danger angle. You stay in safe water as long as the measured vertical angle is:

Question

Accepted Answer

Less than the danger angle — a larger angle means you are closer than the safe distance. A larger vertical sextant angle means a shorter distance off. The danger angle corresponds to the minimum safe distance; keeping the measured angle smaller than the danger angle keeps you farther off than the safe distance. (Authority: Bowditch (Pub. No. 9), vertical danger angle.)

Using a single charted object of known height to clear a hazard at a fixed minimum distance, you set a vertical danger angle. You stay in safe water as long as the measured vertical angle is:

Explanation

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