Method and device for vertically guiding an aircraft during an approach of a runway along a lateral approach trajectory
First Claim
1. A method of vertical guidance of an aircraft during an approach to a landing runway along a lateral approach trajectory, the method comprising successive steps of automatically and repeatedly:
- a) determining a current distance corresponding to a distance in a lateral plane along the lateral approach trajectory, between a current position of the aircraft and a threshold of the landing runway;
b) extracting from a linear terrain profile stored in a database and defined along the lateral approach trajectory, a terrain height for the current distance, the terrain height being defined with respect to a level of the threshold of the landing runway;
c) determining a current height of the aircraft with respect to the terrain height, using at least one measurement taken by at least one on-board radar altimeter at the current position;
d) computing a first current altitude of the aircraft, with respect to the level of the threshold of the landing runway, using the current height of the aircraft and the terrain height;
e) computing an approach profile corresponding to a half-line having a predetermined angle with respect to a horizontal and comprising an endpoint that is situated on the landing runway at a predetermined distance defined by a difference in distance between the endpoint and the threshold of the landing runway, wherein the half-line comprises a slope corresponding to a change in height above the runway divided by a change in distance along the horizontal at a declination rate determined by the predetermined angle;
f) computing a second current altitude of the aircraft, with respect to the level of the threshold of the landing runway, corresponding to an altitude on the approach profile for the current distance;
g) computing a difference between the first current altitude and the second current altitude; and
h) using the difference to vertically guide the aircraft.
1 Assignment
0 Petitions
Accused Products
Abstract
A method and device including a unit to extract a linear terrain profile stored in memory, a terrain height for a current distance of the aircraft, a unit for determining a current height of the aircraft with respect to the terrain, using at least one measurement taken by a radar altimeter, a unit for computing a first current altitude of the aircraft, using the terrain height and the current height, a unit for computing a second current altitude of the aircraft, corresponding to an altitude on an approach profile of the current position of the aircraft and a unit for computing the difference between the first and second current altitudes, the difference being transmitted to a guidance unit to vertically guide the aircraft.
-
Citations
15 Claims
-
1. A method of vertical guidance of an aircraft during an approach to a landing runway along a lateral approach trajectory, the method comprising successive steps of automatically and repeatedly:
-
a) determining a current distance corresponding to a distance in a lateral plane along the lateral approach trajectory, between a current position of the aircraft and a threshold of the landing runway; b) extracting from a linear terrain profile stored in a database and defined along the lateral approach trajectory, a terrain height for the current distance, the terrain height being defined with respect to a level of the threshold of the landing runway; c) determining a current height of the aircraft with respect to the terrain height, using at least one measurement taken by at least one on-board radar altimeter at the current position; d) computing a first current altitude of the aircraft, with respect to the level of the threshold of the landing runway, using the current height of the aircraft and the terrain height; e) computing an approach profile corresponding to a half-line having a predetermined angle with respect to a horizontal and comprising an endpoint that is situated on the landing runway at a predetermined distance defined by a difference in distance between the endpoint and the threshold of the landing runway, wherein the half-line comprises a slope corresponding to a change in height above the runway divided by a change in distance along the horizontal at a declination rate determined by the predetermined angle; f) computing a second current altitude of the aircraft, with respect to the level of the threshold of the landing runway, corresponding to an altitude on the approach profile for the current distance; g) computing a difference between the first current altitude and the second current altitude; and h) using the difference to vertically guide the aircraft. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A device for vertical guidance of an aircraft during an approach to a landing runway along a lateral approach trajectory, the vertical guidance device comprising at least the following on-board units:
- a tracking unit comprising at least one receiver for determining a current position of the aircraft;
at least one radar altimeter and at least one guidance unit; andthe device further comprising on-board units comprising; a database storing a linear terrain profile defined along the lateral approach trajectory; a first computing unit configured to determine a current distance corresponding to a distance in a lateral plane along the lateral approach trajectory, between the current position of the aircraft and a threshold of the landing runway; a second computing unit configured to extract from the linear terrain profile stored in the database, a terrain height for the current distance, determined by the first computing unit, the terrain height defined with respect to a level of the threshold of the landing runway; a third computing unit configured to determine a current height of the aircraft with respect to the terrain height, using at least one measurement taken by the radar altimeter at the current position; a fourth computing unit configured to compute a first current altitude of the aircraft, with respect to the level of the threshold of the landing runway, using the terrain height and the current height of the aircraft, received from the second and third computing units respectively; a fifth computing unit configured to compute an approach profile corresponding to a half-line having a predetermined angle with respect to a horizontal and comprising an endpoint that is situated on the landing runway at a predetermined distance defined by a difference in distance between the endpoint and the threshold of the landing runway and a second current altitude of the aircraft, with respect to the level of the threshold of the landing runway, corresponding to an altitude on the approach profile of the current position; and a sixth computing unit configured to compute a difference between the first current altitude and the second current altitude, received from the fourth and fifth computing units, respectively, the difference being transmitted to the guidance unit that uses the difference to vertically guide the aircraft; wherein each of the first computing unit, the second computing unit, the third computing unit, the fourth computing unit, the fifth computing unit, and the sixth computing unit comprises a hardware processor; and wherein the half-line comprises a slope corresponding to a change in height above the runway divided by a change in distance along the horizontal at a declination rate determined by the predetermined angle. - View Dependent Claims (14)
- a tracking unit comprising at least one receiver for determining a current position of the aircraft;
-
15. An aircraft comprising:
-
a vertical guidance device configured for vertical guidance of the aircraft during an approach to a landing runway along a lateral approach trajectory, the vertical guidance device comprising at least the following on-board units;
a tracking unit comprising at least one receiver for determining a current position of the aircraft;
at least one radar altimeter and at least one guidance unit; andthe device further comprising on-board units comprising; a database storing a linear terrain profile defined along the lateral approach trajectory; a first computing unit configured to determine a current distance corresponding to a distance in a lateral plane along the lateral approach trajectory, between the current position of the aircraft and a threshold of the landing runway; a second computing unit configured to extract from the linear terrain profile stored in the database, a terrain height for the current distance, determined by the first computing unit, the terrain height defined with respect to a level of the threshold of the landing runway; a third computing unit configured to determine a current height of the aircraft with respect to the terrain height, using at least one measurement taken by the radar altimeter at the current position; a fourth computing unit configured to compute a first current altitude of the aircraft, with respect to the level of the threshold of the landing runway, using the terrain height and the current height of the aircraft, received from the second and third computing units respectively; a fifth computing unit configured to compute an approach profile corresponding to a half-line having a predetermined angle with respect to a horizontal and comprising an endpoint that is situated on the landing runway at a predetermined distance defined by a difference in distance between the endpoint and the threshold of the landing runway and a second current altitude of the aircraft, with respect to the level of the threshold of the landing runway, corresponding to an altitude on the approach profile of the current position; and a sixth computing unit configured to compute a difference between the first current altitude and the second current altitude, received from the fourth and fifth computing units, respectively, the difference being transmitted to the guidance unit that uses the difference to vertically guide the aircraft; wherein each of the first computing unit, the second computing unit, the third computing unit, the fourth computing unit, the fifth computing unit, and the sixth computing unit comprises a hardware processor; and wherein the half-line comprises a slope corresponding to a change in height above the runway divided by a change in distance along the horizontal at a declination rate determined by the predetermined angle.
-
Specification