An autopilot is an electronic and mechanical control system that ensures an aircraft follows a pre-programmed flight plan. The autopilot (automated pilot) monitors the course and speed of the aircraft and corrects any deviations from the flight plan. Autopilots do not replace a human operator, but assist them in controlling the vehicle, allowing the human pilot to focus on broader aspects of operation, such as monitoring the trajectory, weather, and systems.

Autopilot systems range from simple wing-levellers to computer-operated units consisting of a gyroscope; an electric servomechanism; and an accelerometer, which measures the acceleration of the aircraft.