On which headings do acceleration and deceleration errors not occur?

Acceleration and deceleration errors in an aircraft's magnetic compass occur due to the dynamic forces acting on the compass fluid when the aircraft experiences changes in speed. Specifically, when an aircraft accelerates, the compass tends to indicate a turn towards the North, and when it decelerates, it tends to show a turn towards the South.

However, when flying on headings aligned with true North and South, these errors are minimized. This is because the magnetic compass relies on the Earth's magnetic field to provide directional guidance, and at these headings, the magnetic influence is oriented such that the impact of acceleration and deceleration is less pronounced.

In contrast, when heading East or West, these errors can become significant. The compass may lag or lead in its indications due to the forces acting on it during acceleration or deceleration, leading to potential navigation discrepancies. This understanding of how the compass behaves under different flight conditions is crucial for effective navigation and safety during flight operations. Hence, the correct answer is that acceleration and deceleration errors do not occur on the North and South headings.