Method and device for ensuring the safety of a low-altitude flight of an aircraft

• US 20050261811A1
• Filed: 05/13/2005
• Published: 11/24/2005
• Est. Priority Date: 05/18/2004
• Status: Active Grant

• Current Assignee: Airbus Operations SAS (Airbus SE)
• Original Assignee: Airbus Operations SAS (Airbus SE)
• Inventors: Artini, Franck, Demortier, Jean-Pierre, Bouchet, Christophe, Strongman, Edward, Espinasse, Jacques
• Granted Patent: US 7,761,193 B2
• Time in Patent Office: Days
• US Class Current: 701/3
• CPC Class Codes: G01C 5/005 altimeters for aircraft G01C5/02, G01C5/06 take precedence
• CPC Class Codes: G05D 1/0646 to follow the profile of undulating ground

Abstract

Method and device for ensuring the safety of a low-altitude flight of an aircraft.

A device (1) for ensuring the safety of a low-altitude flight comprises information sources (5) able to determine current flight conditions, a monitoring unit (6) for realizing, with the aid of said current flight conditions, a function for global and autonomous monitoring of said low-altitude flight of the aircraft, making it possible to preserve the integrity of said aircraft during said flight, and means (13) for presenting the results of the monitoring function realized by said monitoring unit (6) to an operator.

Claims

1. A method of ensuring the safety of a low-altitude flight of an aircraft (A) which is guided along a flight trajectory (TO), comprising a lateral trajectory (TL) and a vertical trajectory (TV), wherein:

current flight conditions are determined;

a function for global and autonomous monitoring of said low-altitude flight of the aircraft (A) is realized, with the aid of said current flight conditions, making it possible to preserve the integrity of said aircraft (A) during said flight; and

the results of the monitoring function thus realized are presented to an operator.

2. The method as claimed in claim 1,

wherein, to realize said monitoring function, a first monitoring is realized so as to verify the compatibility of the flight trajectory (TO) with the terrain to be overflown.

3. The method as claimed in claim 2,

wherein said first monitoring consists in verifying that the vertical trajectory (TV) of the flight trajectory (TO), translated vertically downward by a predetermined guard height, does not intercept the terrain (4).

4. The method as claimed in claim 3,

wherein, to realize said first monitoring, the following operations are performed for each curvilinear abscissa of the lateral trajectory (TO) of the flight trajectory (TO):

the highest altitude under an uncertainty surface related to said curvilinear abscissa is determined;

this altitude is increased by said guard height so as to form a safety altitude; and

a check is carried out to verify that the altitude of said curvilinear abscissa is greater than said safety altitude.

5. The method as claimed in claim 1,

wherein, to realize said monitoring function, a second monitoring is realized so as to verify that said flight trajectory (TO) is continuous and maneuverable by the aircraft (A).

6. The method as claimed in claim 5,

wherein, to realize said second monitoring, the following operations are performed for each curvilinear abscissa of the lateral trajectory (TL) of the flight trajectory (TO):

the lateral and vertical radii of curvature corresponding respectively to the lateral trajectory (TL) and to the vertical trajectory (TV) are determined at said curvilinear abscissa;

on the basis of these lateral and vertical radii of curvature are determined;

a first load factor corresponding to a static load factor due to a turn at constant slope; and

a second load factor corresponding to a vertical load factor due to a vertical transition at constant course; and

a check is carried out to verify that said first and second load factors remain less than predetermined maximum values.

7. The method as claimed in claim 1,

wherein, to realize said monitoring function, a third monitoring is realized so as to verify that the thrust of the aircraft (A) required to maintain the slope and the preset speed such as they are defined for the flight trajectory (TO), remains less than the maximum thrust available in the case of a fault with an engine of the aircraft (A).

8. The method as claimed in claim 1,

wherein, to realize said monitoring function, a fourth monitoring is realized so as to verify the compatibility of the vertical trajectory (TV) with updated theoretical performance of the aircraft (A).

9. The method as claimed in claim 8,

wherein, to realize said fourth monitoring, a protection profile (27) is projected onto the vertical trajectory (TV) from the current position (P1, P2, P3) of the aircraft (A), downstream, along said vertical trajectory (TV), and a check is carried out to verify that said protection profile (27) thus projected does not intercept said vertical trajectory (TV).

10. The method as claimed in claim 8,

wherein, to realize said fourth monitoring, a protection profile (27) is associated with each peak of the vertical trajectory (TV), and a check is carried out to verify the compatibility of the position of the aircraft (A) with respect to said protection profile (27).

11. The method as claimed in claim 9,

wherein said protection profile (27) depends on the capacity of the aircraft (A) to perform a resource at constant speed and constant load factor and a climb at constant speed and at maximum slope.

12. The method as claimed in claim 9,

wherein said protection profile (27) comprises a circular arc (31) of constant radius and a rectilinear segment (32) of maximum slope.

13. The method as claimed in claim 8,

wherein, when said fourth monitoring detects an incompatibility, the vertical trajectory (TV) is automatically corrected ahead of the aircraft (A) in such a way as to eliminate this incompatibility.

14. The method as claimed in claim 1,

wherein, to realize said monitoring function, a fifth monitoring is realized so as to verify the compatibility of the vertical trajectory (TV) with actual performance of the aircraft (A).

15. The method as claimed in claim 14,

wherein, to realize said fifth monitoring:

a first maximum slope is determined which represents the maximum slope at which the aircraft (A) can fly under the current flight conditions with a faulty engine;

a second maximum slope is determined which represents the maximum slope at which the aircraft (A) can fly under the current flight conditions with all its engines operational;

a preset slope is determined allowing the aircraft (A) to fly along said flight trajectory (TO); and

a check is carried out to verify that said preset slope is compatible with said first and second maximum slopes.

16. The method as claimed in claim 15,

wherein said first and second maximum slopes are determined from the current total slope of the aircraft (A).

17. The method as claimed in claim 1,

wherein, to realize said monitoring function, a sixth monitoring is realized so as to detect any excessive deviation of the position of the aircraft (A) with respect to said flight trajectory (TO).

18. The method as claimed in claim 1,

wherein said current flight conditions comprise the current meteorological conditions and current characteristics of the aircraft (A).

19. The method as claimed in claim 1,

wherein a function for ensuring the safety of the flight trajectory (TO) during its construction is implemented.

20. A device for ensuring the safety of a low-altitude flight of an aircraft (A) which is guided along a flight trajectory (TO),

which device comprises,

information sources (5) able to determine current flight conditions;

a monitoring unit (6) for realizing, with the aid of said current flight conditions, a function for global and autonomous monitoring of said low-altitude flight of the aircraft (A), making it possible to preserve the integrity of said aircraft (A) during said flight; and

means (13) for presenting the results of the monitoring function realized by said monitoring unit (6) to an operator.

21. The device as claimed in claim 20,

wherein said monitoring unit (6) comprises:

a first monitoring means (16) for verifying the compatibility of the flight trajectory (TO) with the terrain to be overflown;

a second monitoring means (17) for verifying that said flight trajectory (TO) is continuous and maneuverable by the aircraft (A);

a third monitoring means (25) for verifying that the thrust of the aircraft (A) required to maintain the slope and the preset speed such as they are defined for the flight trajectory (TO) remains less than the maximum thrust available in the case of a fault with an engine of the aircraft (A);

a fourth monitoring means (26) for verifying the compatibility of the vertical trajectory (TV) with updated theoretical performance of the aircraft (A);

a fifth monitoring means (42) for verifying the compatibility of the vertical trajectory (TV) with actual performance of the aircraft (A); and

a sixth monitoring means (43) for detecting any excessive deviation of the position of the aircraft (A) with respect to said flight trajectory (TO).

22. The device as claimed in claim 20,

wherein it furthermore comprises means (38) for automatically updating said flight trajectory (TO).

23. The device as claimed in claim 20,

wherein it furthermore comprises a means for implementing a function for ensuring the safety of the flight trajectory (TO) during its construction.

24. An aircraft,

which comprises a device (1) such as that specified under claim 20.