Plain English Meaning

A mode that lets the autopilot fly the side-to-side path you have programmed into the navigation computer, automatically turning at each waypoint to stay on the planned route.

Full Definition

LNAV mode is a flight guidance mode in which the autopilot or flight director steers the aircraft laterally (left and right) along a programmed RNAV course defined in the flight management system or GPS navigator. It controls heading and track to follow the magenta line of the active flight plan, including straight legs, course changes at , and curved path segments where coded.