During which phase of flight is the autopilot most commonly used?

The autopilot is most commonly used during the cruise phase of flight because this phase involves maintaining a steady altitude and speed over extended periods, allowing the pilots to focus on monitoring the flight path rather than manipulating the controls constantly. In cruise, the aircraft is typically at a stable altitude where the autopilot can efficiently manage the flight’s performance while minimizing pilot workload.

During takeoff, the pilot needs to actively manage the aircraft's thrust and attitude as it transitions from ground to airborne, making it impractical to rely on autopilot. In the climb phase, while the autopilot may be engaged to assist, it requires frequent adjustments based on changing speed and configuration, especially as the aircraft transitions through various airspeeds and altitudes. Finally, in the descent phase, even though autopilot can be utilized, it usually requires more pilot input to monitor and adjust for atmospheric conditions and to prepare for the landing approach, further limiting the extensive use of autopilot compared to the cruise phase.