Which type of variation is associated with magnetic influence from an aircraft's internal components?

Deviation refers to the difference between the magnetic heading indicated by an aircraft's magnetic compass and the true magnetic heading, caused by local magnetic fields generated by the aircraft's internal components and electronic equipment. These variations occur because the compass may be affected by magnetic interference from the aircraft's structure or systems, leading to discrepancies in heading readings.

In aviation, it’s essential for pilots and air traffic controllers to account for this deviation to ensure accurate navigation. The term 'magnetic variation,' on the other hand, pertains to the difference between true north and magnetic north that exists in different geographic locations, while 'true variation' and 'agonic variation' refer to variations related to Earth's magnetic field but not to internal influences on the compass. Understanding the impact of deviation is critical for maintaining precise navigation and ensuring safety in air traffic operations.