Question 9Navigation Problems
70% to passOn 22 July at 0448 ZT, morning stars were observed, and the vessel's position was determined to be LAT 21°43.0'N, LONG 158°39.0'E. Your vessel is steaming at 21.0 knots on a course of 028°T. A sextant observation of the Sun's lower limb is made at 0956 ZT. The chronometer reads 10h 54m 27s, and the sextant altitude is 54°28.2'. The index error is 1.5' off the arc, and the chronometer error is 01m 38s slow. Your height of eye on the bridge is 56 feet. What is the azimuth (Zn) of this sight using the assumed position?
The correct answer is A) 086.9°T. The explanation is as follows: 1. The answer A) 086.9°T is correct, as it represents the calculated azimuth (Zn) of the Sun's lower limb observation based on the given information. 2. The reasoning to arrive at this answer involves applying the standard nautical navigation formulas and procedures for calculating the azimuth from a celestial observation, taking into account the vessel's position, course, speed, the Sun's altitude, the chronometer error, and the index error. 3. The other answer choices are incorrect because they do not represent the proper azimuth calculation for the given scenario. 4. The step-by-step workings to arrive at the correct azimuth of 086.9°T are not provided here, but they would involve the application of spherical trigonometry and nautical astronomy principles taught in the US Coast Guard Captain's License Examinations.
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