In aviation, what is magnetic variation?

Magnetic variation, also known as magnetic declination, refers to the difference in angular measurement between magnetic north (the direction a magnetic compass points) and true north (the direction along Earth's surface towards the geographic North Pole). Understanding magnetic variation is crucial for navigation, as it allows pilots and navigators to adjust their compass readings to ensure accurate course plotting.

This concept is essential in aviation since navigational charts often include this information to help pilots align their flight paths with true bearings. Accurate navigation is vital for safety and efficiency in flight operations, making a clear understanding of magnetic variation important for all aviation professionals.

The other options do not correctly define magnetic variation. Electrical interference pertains to issues affecting electronic instruments but does not relate directly to magnetic declination. The oscillation of the compass could refer to various compass inaccuracies but isn't synonymous with magnetic variation. Northern turning errors relate to mistakes made while turning the aircraft toward the north but are separate from the fundamental concept of measuring variation between different types of north.