Compasses Mass Brief N S S N Pivot Line Weight Side View Considerations N S N S Pivot Line Weight N S • Acceleration errors – Due to CoG displacement, acceleration errors occur. As aircraft accelerates, pivot point moves with the aircraft, but the magnet is left behind causing errors, until it is realigned. Side View Top View Considerations • In the southern hemisphere SAND • South Accelerate, North Decelerate West Apparent turn to the South Apparent turn to the North South None None East Apparent turn to the South Apparent turn to the North North None None HDG Acceleration Error Deceleration Error 000 180 270 090 N S Considerations • Turning Errors – The centripetal force of the turn pulls the pivot point of the compass into the turn, but the magnet is left behind again • In the southern hemisphere ONUS • Overshoot through North, Undershoot through South HDG 330 HDG 030 000 180 270 090 N S 030 HDG 330 HDG 030 000 180 270 090 N S 330 Considerations • Turning through south HDG 150 HDG 210 000 180 270 090 N S 150 HDG 150 HDG 210 000 180 270 090 N S 210