Description
Autopilots in modern complex aircraft are three-axis and generally divide a flight into taxi, takeoff, climb, cruise (level flight), descent, approach, and landing phases. Autopilots that automate all of these flight phases except taxi and takeoff exist. An autopilot-controlled approach to landing on a runway and controlling the aircraft on rollout (i.e. keeping it on the centre of the runway) is known as an Autoland, where the autopilot utilizes an Instrument Landing System (ILS) Cat IIIc approach, which is used when the visibility is zero. These approaches are available at many major airports' runways today, especially at airports subject to adverse weather phenomena such as fog. The aircraft can typically stop on their own, but will require the disengagement of the autopilot in order to exit the runway and taxi to the gate. An autopilot is often an integral component of a Flight Management System.Modern autopilots use computer software to control the aircraft. The software reads the aircraft's current position, and then controls a flight control system to guide the aircraft. In such a system, besides classic flight controls, many autopilots incorporate thrust control capabilities that can control throttles to optimize the airspeed.
