Magnetic Variation to find Magnetic Direction
To find the magnetic bearing subtract the magnetic variation if the True Track is east of zero magnetic variation or add the True Track if it is west zero magnetic variation.
Example: If the True track taken from a WAC map is 090T through Brisbane Airport then subtract the printed magnetic variation 11E from the WAC map for that area (090 - 11 = 079). The Magnetic track will be 079M
Note: Magnetic Deviation is the difference between the magnetic north and the actual direction the compass points, due to magnetic influences surrounding the compass (i.e. metal aircraft components like fuselage, wings and other avionic instrumental influences). The calibration of deviation is the same system as used with variation. To find a magnetic bearing subtract the magnetic deviation if the compass points east of magnetic north or add magnetic deviation if the compass points west of magnetic north.