Explain the difference between magnetic variation and compass deviation, and give the correct sequence for converting a true direction to a compass direction.

### Why this is right The definitions differ by the north references being compared. Variation links true and magnetic north, while deviation links magnetic north and compass north. Those links determine the conversion order. ### The concept A true direction is referenced to true north. Apply variation to express it relative to magnetic north. Then apply deviation to obtain the compass reference. The aircraft's magnetic influences can affect the compass, which is why deviation is distinct from the geographically defined variation. The mnemonic “True, Variation, Magnetic, Deviation, Compass” preserves the sequence. ### What a good answer covers - Variation is between true north and magnetic north. - Deviation is between magnetic north and compass north. - Variation is applied before deviation. - State the east-west sign convention when performing a numerical conversion. ### Terms - **Compass north**: The north reference shown by the aircraft compass. - **Magnetic influence**: An aircraft-related effect that can affect compass indication. ### Remember The shared word “magnetic” is the intermediate reference between the two corrections.