Chart Navigation & Plotting · Compass Error
Your true course is 045°, variation is 5°E and deviation is 3°W. The compass course to steer is:
- A047°
- B043°✓ Correct
- C053°
- D037°
Explanation
Going from true to compass you 'uncorrect' — subtract easterly, add westerly. True 045° − 5°E variation = 040° magnetic; 040° + 3°W deviation = 043° compass. The compass course to steer is 043°.
Authority: Bowditch, American Practical Navigator (Pub. 9), TVMDC
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