On 23 October in DR position LAT 21°13.0'N, LONG 152°18.0'E, you observe an amplitude of the Sun. The Sun's center is on the visible horizon and bears 259°psc. The chronometer reads 07h 21m 46s and is 01m 32s slow. Variation in the area is 5°E. What is the deviation of the magnetic compass?
Official USCG Answer & Rule Citation
Correct Answer: Option D — 5.9°W
Sunrise or sunset amplitude equations establish the body's true bearing at the horizon. Comparing true bearing to the standard compass bearing and factoring local easterly or westerly variation isolates the compass deviation.
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