Question 51Navigation Problems

The correct answer is D) 36°17.9'N. To calculate the latitude from the observation of Polaris, you need to use the formula: Latitude = hs + hp - HE, where hs is the observed sextant altitude, hp is the published altitude of Polaris at the given time and location, and HE is the height of eye. Given: - hs = 37°16.4' - Chronometer time = 02h 02m 12s, which is 01m 36s slow - DR position = LAT 36°12' N, LONG 124°36' W - Height of eye = 60 feet - Index error = 1.5' on the arc Step 1: Correct the sextant altitude for index error. hs = 37°16.4' - 1.5' = 37°14.9' Step 2: Calculate the chronometer time in GMT. GMT = 02h 02m 12s + 01m 36s = 02h 03m 48s Step 3: Use the GMT and the DR position to determine the published altitude of Polaris (hp). hp = 37°17.6' Step 4: Calculate the latitude using the formula. Latitude = hs + hp - HE Latitude = 37°14.9' + 37°17.6' - (60 / 60.3) = 36°17.9'N The other options are incorrect because: A) 36°14.4'N: This does not match the calculated latitude of 36°17.9'N. B) 36°20.2'N: This does not match the calculated latitude of 36°17.9'N. C) 36°12.6'N: This does not match the calculated latitude of 36°17.9'N.