How do the autopilot and flight director interact on a typical narrowbody, and when are they engaged or disengaged?

• A. Autopilot controls flight surfaces to follow guidance; flight director provides command cues; autopilot is engaged after takeoff per SOP and disengaged during approach or as required in abnormal situations.
• B. Autopilot and flight director are the same system; there is no disengagement.
• C. Autopilot only works on final approach; flight director only during takeoff.
• D. Flight director can fly the airplane without autopilot in all phases.

Answer: (A)

Autopilot and flight director serve different but complementary roles in flight guidance. The autopilot is the system that actually flies the aircraft by moving the control surfaces to follow a selected path. The flight director, on the other hand, is a guidance display that presents command cues (pitch and roll targets) to the pilot; it shows the intended flight path but does not move the controls by itself.

When both are in use, the autopilot will follow the flight director’s commands, translating those cues into automatic aircraft control. After takeoff, crews typically engage the autopilot per standard operating procedures to manage the climb and acceleration. As you approach, the autopilot is geared for potential disengagement depending on the situation—often it is disengaged for a manual landing or as required in abnormal situations—while the flight director can still provide guidance to the pilot if manual control is being used.

The other options aren’t correct because they either state the two systems are the same, limit autopilot or flight director to specific phases, or imply the flight director can fly the airplane without autopilot in all phases.