On 11 January your vessel's 0655 zone time DR position is LAT 24°30'N, LONG 122°02'W, when an amplitude of the Sun is observed. The Sun's center is on the celestial horizon and bears 101.0° per standard compass. Variation in the area is 11.6°E. The chronometer reads 02h 52m 48s and is 02m 12s slow. What is the deviation of the standard compass?

Question

On 11 January your vessel's 0655 zone time DR position is LAT 24&deg;30'N, LONG 122&deg;02'W, when an amplitude of the Sun is observed. The Sun's center is on the celestial horizon and bears 101.0&deg; per standard compass. Variation in the area is 11.6&deg;E. The chronometer reads 02h 52m 48s and is 02m 12s slow. What is the deviation of the standard compass?

Accepted Answer

Option A: 1.4&deg;E. Calculate the true amplitude using the Sun's declination and observer's latitude. Compare the true amplitude to the compass amplitude (101.0 degrees) to find the compass error. Applying the 11.6 degrees East variation to the total compass error results in a deviation of 1.4 degrees East.