Method for enabling landing on an offset runway
A method for determining the distance of an aircraft from an offset runway during a landing by offset approach, the offset runway being situated at a distance D from a main runway equipped with at least one elevation beacon, comprises at least the following steps: determining the height h at which the aircraft is situated, height determined with respect to a point T 1 of the offset runway, height measured by a radioaltimeter with which the aircraft is equipped, determining the angle of elevation φ of the MLS mode by using the information of the elevation beacon provided by an elevation beacon with which said main runway is equipped, determining the value of the distance ρ of the aircraft from the azimuth beacon ( 10 ) by using the following formula ρ = ( h Tan ( φ ) - D 2 Cos ( θ ) ) 2 + h 2 , and, using said distance ρ to obtain a point of location of the aircraft in an offset runway reference frame.
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 1 of the offset runway, the height being measured by the radioaltimeter with which the aircraft is equipped and thus corresponds to a perpendicular height between the aircraft and ground,
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:
ρ
=
(
h
Tan
(
φ
)
-
D
2
Cos
(
θ
)
)
2
+
h
2
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.
2. The method as claimed in claim 1 , wherein the distance ρ is used in a reconstruction algorithm utilized by the MMR described in at least one of the standard DO198 and the standard DO226.