Chart Navigation & Plotting · Compass — Correcting to True
Your compass course is 220°. Deviation is 3°E and variation is 5°W. What is the true course?
- A228°T
- B222°T
- C218°T✓ Correct
- D212°T
Explanation
Correcting (compass to true): add easterly, subtract westerly. Magnetic = 220° + 3°E (dev) = 223°. True = 223° − 5°W (var) = 218°T.
Authority: Bowditch (Pub. No. 9), Compass Error
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