Navigation General · TVMDC Conversion
When CORRECTING (converting compass to true), you apply easterly errors by:
- ASubtracting them
- BAdding them✓ Correct
- CIgnoring them — east errors only apply when uncorrecting
- DReversing their sign first, then adding
Explanation
When correcting (converting compass to true), add easterly errors and subtract westerly errors. When uncorrecting (true to compass), the reverse applies: add westerly errors and subtract easterly errors. The memory aid is 'Correcting Add East' (CAE).
Authority: Bowditch (Pub. 9)
Practice the full Navigation General bank
Free spaced-repetition quizzing across 2190 USCG exam questions — it schedules your reviews so the ones you miss come back until they stick.
Related Navigation General questions
- TVMDC Conversion
Using the mnemonic 'True Virgins Make Dull Compass,' the order of correction from true to compass is:
- TVMDC Conversion
Variation: 10° E, Deviation: 5° W. A true course of 090° converts to what compass course?
- TVMDC Conversion
Variation: 10° E, Deviation: 5° W. A compass course of 085° converts to what true course?
- TVMDC Conversion
Variation: 7° W, Deviation: 3° E. A true course of 180° converts to what compass course?
- TVMDC Conversion
Variation: 7° W, Deviation: 3° E. A compass course of 184° converts to what true course?
- TVMDC Conversion
Variation: 15° E, Deviation: 0°. A true course of 270° converts to what compass course?