What is a variation chart used for in aviation?

A variation chart, also known as a magnetic variation chart, serves a specific purpose in aviation by displaying the magnetic variation across different regions. Magnetic variation, or magnetic declination, indicates the angle between magnetic north and true north at any given location. This information is crucial for pilots and navigators as it allows them to correct their magnetic compass readings to ensure accurate navigation.

By consulting a variation chart, aviators can determine the appropriate correction to apply to their magnetic heading in order to achieve a true heading, which is essential for accurate flight planning and navigation. Knowing the magnetic variation helps in setting courses correctly on navigation instruments and maintaining situational awareness.

Weather patterns, fuel requirements, and aircraft performance metrics support different aspects of aviation operations, but they do not directly relate to the specialized function of a variation chart concerning magnetic navigation.