Chart Navigation & Plotting · Compass — Compass Error
Variation is 9°E and deviation is 4°E. What is the compass error?
- A13°E✓ Correct
- B5°E
- C13°W
- D5°W
Explanation
Both errors are easterly, so they add: 9°E + 4°E = 13°E. (Errors of opposite name would be subtracted, keeping the name of the larger.)
Authority: Bowditch (Pub. No. 9), Compass Error
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