Convert compass course to true course using variation (chart) and deviation (deviation card) - the classical “True Virgins Make Dull Company” chain.
Formula
$$ T = C + D + V $$
Symbol legend
| Symbol | Meaning | Unit | Source |
|---|---|---|---|
| $C$ | Compass course | °C | compass card |
| $D$ | Deviation | °E or W | deviation card |
| $V$ | Variation | °E or W | chart compass rose |
Sources
- Bowditch Pub.9 Ch.6.