Celestial Navigation · Amplitudes — Compass Error
The sun's computed true amplitude gives a rising bearing of 070°T; you observe it rise on a compass bearing of 074°. The compass error is:
- A8°W
- B4°E
- C4°W✓ Correct
- D0°
Explanation
Compass error = true − compass = 070° − 074° = −4°. The compass reads higher than true, so the error is westerly: 4°W.
Authority: Bowditch (Pub. No. 9), Compass Error by Amplitude
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