In what situation would you expect both autopilot systems to be active?

Both autopilot systems are designed to work together to enhance the safety and performance of the aircraft. They can be used concurrently, particularly during critical phases of flight where precise control is essential. The approach phase is one such scenario where dual autopilot operation is not only expected but also often required to manage the increased complexity of landing an aircraft.

During the approach phase, the aircraft is transitioning from cruise altitude to the runway, which involves precise altitude and speed control. Utilizing both autopilot systems allows for increased redundancy; if one system were to fail, the other can take over without significant disruption. The flight management system can execute the approach with high precision, maintaining the necessary glide slope and lateral path to the runway.

In contrasting situations like takeoff, descent, or leveling off, autopilot functionality may be limited or even prohibited based on safety protocols and operational standards. For example, some systems might not engage during takeoff due to the need for pilot control in a dynamic environment, and during descent or leveling off, the focus may shift towards adjusting flight parameters rather than maintaining coordinated operation of both autopilot systems.