Chart Navigation & Plotting · Compass — TVMDC Uncorrecting
Your true course is 045°T. Variation is 10°E and deviation for that heading is 2°W. What is the compass course to steer?
- A053°
- B037°✓ Correct
- C057°
- D033°
Explanation
Going from true to compass (uncorrecting), subtract easterly errors and add westerly. Magnetic = 045° − 10°E (variation) = 035°. Compass = 035° + 2°W (deviation) = 037°. Remember: 'Correcting add east; uncorrecting subtract east.'
Authority: Bowditch (Pub. No. 9), Compass Error
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