FOUR-DIMENSIONAL NAVIGATION OF AN AIRCRAFT

The present invention relates to methods of controlling the flight path of an aircraft to follow as closely as possible a predetermined four-dimensional flight path, such as when flying continuous descent approaches. A method of controlling an aircraft to follow a predetermined four-dimensional flight path is provided that comprises monitoring the actual along-track position and the actual vertical position of the aircraft relative to the corresponding desired positions on the predetermined flight path. The aircraft's elevators are used to correct deviations of the along-track position and the aircraft's throttle is used to correct deviations of the vertical position.