The vehicle essentially flies itself, while an air vehicle operator directs the flight path using a mouse on a digital map display. Automated takeoff and landing are essential elements in achieving this goal. Training pilots and maintaining their proficiency is costly to the military because it requires UAV flight time and risks UAV assets. The ground operator directs the UAV flight path with a waypoint table. Simple waypoints specify locations in three-dimensional space for the UAV to fly through.
Location is specified by latitude, longitude, and altitude.
More complex waypoints define line and arc paths to be followed through three-dimensional space. There are special emergency waypoints that tell the UAV where to go when radio uplink from the ground operator fails. As with any manned aircraft, the most demanding control requirement for a tactical UAV is position accuracy at touchdown during landing. In a manned aircraft, this complicated maneuver requires much skill, training, and practice. In the UAV automated landing function, a vertical velocity controller was used with GPS and inertial sensors to achieve vertical errors less than 4 feet with atmospheric turbulence.