Commercial Pilot License (CPL) 2026 – 400 Free Practice Questions to Pass the Exam

The effects of oscillation on a magnetic compass primarily cause the compass card to move erratically. This erratic movement occurs because oscillation disrupts the steady position that the compass seeks to achieve based on the Earth's magnetic field. When the aircraft is in motion, particularly during turbulence or rapid maneuvers, the oscillation can cause the compass to fluctuate, making it difficult to read and leading to an unstable indication of direction.

Understanding oscillation is crucial for pilots, as it can impact navigation and situational awareness. It is also important to note that while other factors may influence compass readings, such as magnetic deviation and external interference, oscillation specifically contributes to a lack of consistency in the displayed direction, which is why the impact is characterized as erratic movement.