Which description corresponds to Autopilot?

• A. A manual control input required for all phases of flight.
• B. A system that automatically taxis the aircraft.
• C. A satellite navigation system.
• D. An automatic flight control system which keeps an aircraft in level flight or on a set course.

Answer: (D)

Autopilot is an automatic flight control system that handles the aircraft’s flight controls to maintain a desired condition, such as level flight or a predefined course. When engaged, it uses sensor data and navigation inputs to move the elevator, ailerons, and rudder, keeping the aircraft on the selected path and altitude with less manual effort from the pilot. This reduces workload and helps maintain precise flight paths. It’s not describing manual input for all phases, nor simply automatic taxiing on the ground, nor merely a navigation system—autopilot specifically refers to the automatic control system that keeps the aircraft on a set course or in level flight.