What is the angular difference between the initial true track and the final true track on a Lambert's conformal conic chart referred to?

The angular difference between the initial true track and the final true track on a Lambert's conformal conic chart is referred to as chart convergence. This term specifically addresses the angular distortion that occurs due to the projection method used in the chart. A Lambert conformal conic projection is designed for aeronautical navigation as it preserves angles, making it essential for pilots and navigators to understand how this angular difference affects their flight path planning.

In practical terms, chart convergence is critical when determining the true track for a flight. Since the earth is spherical and the chart is a flat representation, the alignment of paths between the beginning and end of a journey can differ due to the chart's design. Navigators must account for this difference to ensure that their route corresponds accurately to the true path over the earth's surface.

Understanding chart convergence enables a more precise calculation of heading adjustments necessary for enroute navigation, particularly over long distances. This awareness of how true tracks translate from a spherical surface to a planar one is key for effective navigation using Lambert's conformal conic charts.