Luckily for us the Earth has a magnetic field which is roughly aligned with the north and south poles. A magnet allowed to rotate freely will align itself with these magnetic poles.

Based on these poles we have determined the directions North, East, South and West and assigned numerical values ranging from 000 to 360.

North- 360 or 000

East- 090

South- 180

West- 270



As a result it allows us to set our course with a relatively high degree of accuracy.



For example if we want to fly precisely

-North East we'll set a course of 045
-South East would be a course of 135
-South West would be a course of 225
-North West would be a course of 315



Compass as seen in most of the helos


The compass and others instruments like it have given us the ability to consistently steer our aircraft on a desired magnetic heading with a reasonably high degree of accuracy which is an integral part of navigation.