Autopilots are electronic systems designed to navigate a vehicle without human input. They are common in aircraft, boats, space vehicles, missiles, and UAVs. These reduce a vehicle operator's workload when travelling long distances that do not require intensive oversight, which could be fatiguing to the operator. Though limitedly available in marine and automobile applications, they are most common in the aerospace industry. Many aerospace regulation agencies require certain types of aircraft to be outfitted with autopilots for safety. Smaller aircraft rely on electronic gyroscopes to determine pitch, roll, and sometimes yaw, while in flight, but rely on hand control for landing, takeoff, and other essential functions. Commerical or military autopilots for larger aircraft have taxi, takeoff, cruise, descent, approach, and landing phases that are governed by computer software integrated into a flight management system. These systems calculate thrust, balance fuel reservoirs, economize fuel consumption, and accommodate for gyroscopic error.
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