Navigation General · TVMDC Conversion
Using the mnemonic 'True Virgins Make Dull Compass,' the order of correction from true to compass is:
- ATrue → Variation → Magnetic → Deviation → Compass✓ Correct
- BTrue → Deviation → Magnetic → Variation → Compass
- CCompass → Deviation → Magnetic → Variation → True
- DTrue → Magnetic → Variation → Deviation → Compass
Explanation
TVMDC: True → apply Variation → Magnetic → apply Deviation → Compass. Reading left to right, each step converts toward the compass reading. Reading right to left converts compass toward true.
Authority: Bowditch (Pub. 9)
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