Deviation

Navigation

DEV

Deviation is the error of a magnetic compass caused by magnetic fields in the aircraft. It is the angular difference between magnetic north or magnetic heading and what the compass indicates at that moment. It changes with aircraft heading and electrical or metal influences, so it is usually shown on a deviation card after compass swinging. When you use a magnetic compass for navigation, apply deviation with the correct sign to convert between compass and magnetic values.

Also known as

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