Question 13Navigation Problems70% to pass
While enroute from Cape Town to Rio a vessel's course is 281°pgc. The variation for the locality is 24°W. The deviation is 4°E. The gyro error is 2°W. What is the true course made good?
AI Explanation
The correct answer is B) 279°T.
To arrive at this answer, we need to convert the given course of 281°pgc (compass course) to the true course made good.
First, we need to apply the variation of 24°W to the compass course, which gives us 281°pgc - 24°W = 257°T.
Next, we need to apply the deviation of 4°E, which gives us 257°T + 4°E = 261°T.
Finally, we need to apply the gyro error of 2°W, which gives us 261°T - 2°W = 279°T.
The other options are incorrect because they do not properly account for the variation, deviation, and gyro error in the correct sequence to arrive at the true course made good.
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