A flight director can be used with or without automation of the flight control surfaces.[2] The FD is commonly used in direct connection with the Autopilot (AP), where the FD commands the AP to put the aircraft in the attitude necessary to follow a trajectory. The FD/AP combination is typically used in autopilot coupled low instrument approaches (below 200 feet above ground level [AGL]), or CAT II and CAT III ILS instrument approaches.