You swung ship and compared the magnetic compass against the gyro compass to find deviation. Gyro error is 2°E. The variation is 8°W. Find the deviation on a gyro heading of 196°. HEADING PSC-PGC 030.5°-020° 092.0°-080° 106.5°-050° 122.5°-110° 152.0°-140° 181.0°-170° 210.0°-200° 239.5°-230° 269.0°-260° 298.0°-290° 327.5°-320° 358.5°-350°
Official USCG Answer & Rule Citation
Correct Answer: Option D — 0.0°
Convert the gyro heading of 196° to True using 2°E error (198°T). Using the table, find the corresponding PSC heading. Applying the 8°W variation to the True heading gives the magnetic heading. Comparing this to the PSC heading confirms the deviation is 0.0° for this specific ship's heading.
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