Aircraft navigational systems and methods for creating navigational

Abstract

Aircraft navigational system and methods are disclosed for creating aircraft navigational guidepoints during in-flight operations. A digital computer and computer control displays provide dynamic and static display of the aircraft relative to the flight path and earth referenced data. In one embodiment, a new guidepoint is located and displayed at the intersection of a pilot selected radial and a track line, such as the aircraft projected flight path, defined by a series of guidepoints which are stored in the computer. The selected radial emanates from a selected geographical location defined by a known latitude/longitude, such as for example, preprogrammed NAVAIDS, geographical reference points and pilot entered geographical locations. The latitude/longitude and place-bearing-distance of the new guidepoint is calculated by first determining the great circle distance and true bearing from the NAVAID to each of the guidepoints using spherical geometry, and then comparing the true bearing of the selected radial to each set of adjacent guidepoints to determine between which set of adjacent guidepoints the selected radial lies. Then using geometric relationships and spherical geometry, the place-bearing-distance of the new guidepoint is determined.