Question 19Navigation Problems70% to pass
On 2 April your 0830 zone time fix gives you a position of LAT 20°16.0'S, LONG 004°12.0'E. Your vessel is steaming a course of 143°T at a speed of 18.0 knots. An observation of the Sun's upper limb is made at 0903 zone time, and the observed altitude (Ho) is 42°39.6'. The chronometer reads 09h 05m 40s, and the chronometer error is 02m 15s fast. Local apparent noon occurs at 1145 zone time, and a meridian altitude of the Sun's lower limb is made. The observed altitude (Ho) for this sight is 63°46.2'. Determine the vessel's 1200 zone time position.
AI Explanation
The correct answer is C) LAT 21°18.0'S, LONG 005°00.5'E.
The reasoning is as follows:
1. Using the given information on the fix, course, speed, sun observations, and local apparent noon, the vessel's position can be calculated using celestial navigation principles.
2. The calculations involve using the sun's observed altitude, zenith distance, and local apparent time to determine the vessel's latitude and longitude at 1200 zone time.
3. The other options are incorrect because they do not match the final calculated position based on the provided data.
4. The step-by-step working to arrive at the correct answer C is consistent with the standard procedures for determining a vessel's position using celestial navigation techniques.
Related Questions
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