Patent ID: 8682510
Filing Date: 2014-03-25
Classification: G01S,G08G

Abstract:
1. A method for determining a distance of an aircraft from an offset runway during a landing by offset approach utilizing a Multimode Reception Device (MMR) and a radioaltimeter, the offset runway being situated at a distance D from a main runway equipped with at least one elevation beacon, comprising: determining a height h at which the aircraft is situated, the height being determined with respect to a point T determining an angle of elevation φ based on a MLS mode of the MMR by using information provided by the at least one elevation beacon with which said main runway is equipped, determining a value of a distance ρ of the aircraft from an azimuth beacon by using the following formula: where θ and φ are angles decoded by the MMR corresponding respectively to an angle between the aircraft and the azimuth beacon and an angle between the aircraft and the elevation beacon, and D 2 is defined as a distance between the azimuth beacon and the elevation beacon along the x axis, with x, y and z coordinates of the aircraft being in a reference frame of the elevation beacon, using said distance ρ to obtain a point of location of the aircraft in an offset runway reference frame.