Chart Navigation & Plotting · Compass Error
Variation 8°W, deviation 2°E. The compass error is:
- A10°E
- B6°W✓ Correct
- C10°W
- D6°E
Explanation
Compass error is the algebraic sum of variation and deviation, combining like signs and differencing unlike. 8°W and 2°E: 8 − 2 = 6, and the larger (variation) is West, so the error is 6°W.
Authority: Bowditch, American Practical Navigator (Pub. 9), compass error
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