Patent ID: 9725157
Date: 2017-08-08
CPC Classifications: G08G

Claim:
1. A method for automatic comparison of a first flight trajectory and a second flight trajectory for an aircraft, wherein the first flight trajectory includes a first vertical trajectory and a first lateral trajectory, and the second flight trajectory includes a second vertical trajectory and a second lateral trajectory, wherein the first lateral trajectory and the second lateral trajectory each include a succession of lateral segments, with each lateral segment being defined by corresponding geometric parameters which describe a shape of the lateral segment and identify respective lateral departure and arrival points for the lateral segment, and the first vertical trajectory and the second vertical trajectory each include a succession of vertical segments, with each vertical segment being defined by corresponding geometric parameters which describe a shape of the vertical segment and identify respective vertical departure and arrival points for the vertical segment, the method comprising: a) receiving the first flight trajectory and the second flight trajectory; b) automatically carrying out at least one of the following comparison steps b1 and b2: b1) comparing the first lateral trajectory and the second lateral trajectory of the first and second flight trajectories, wherein the comparison is performed by comparing the corresponding geometric parameters describing the shapes and the respective departure and arrival points of successive lateral segments of the first and second lateral flight trajectories, rather than comparing individual points along the first and second lateral trajectories, and wherein the comparison is continued for as long as the respective successive lateral segments of the first and second lateral flight trajectories are identical over a predetermined distance in a horizontal plane; and b2) comparing the first vertical trajectory and the second vertical trajectory of the first and second flight trajectories, wherein the comparison is performed by comparing the corresponding geometric parameters describing the shapes and respective departure and arrival points of successive vertical segments of the first and second vertical flight trajectories, rather than comparing individual points along the first and second vertical trajectories, and wherein the comparison is continued for as long as the respective successive vertical segments of the first and second vertical flight trajectories are identical over the predetermined distance in the horizontal plane; and c) transmitting automatically the result of the comparison carried out in step b1) or b2) to a guidance device comprising an automatic pilot and/or flight director of the aircraft, a display that presents graphical information to a crew in the aircraft cockpit and a trajectory change unit that changes the first flight trajectory of the aircraft to the second flight directory where the comparison carried out in step b1) or b2) indicates that the first and second flight trajectories are the same for the predetermined distance.