METHOD AND DEVICE FOR AUTOMATICALLY CONTROLLING AN EMERGENCY DESCENT OF AN AIRCRAFT

• US 20090228161A1
• Filed: 03/10/2009
• Published: 09/10/2009
• Est. Priority Date: 03/10/2008
• Status: Active Grant

• Current Assignee: Airbus Operations SAS (Airbus SE)
• Original Assignee: Airbus France
• Inventors: Joignet, Jean-Philippe, BOTARGUES, Paule
• Granted Patent: US 8,078,345 B2
• Time in Patent Office: Days
• US Class Current: 701/11
• CPC Class Codes: G05D 1/0055 with safety arrangements
• CPC Class Codes: G05D 1/0688 Emergency descent

Abstract

Method and device for the automatic control of an emergency descent of an aircraft

The device (1) comprises means (2) for automatically engaging an emergency descent function of an aircraft, as a function of a variation in the pressure measured in the cabin of the aircraft.

Claims

1. A method of automatic control of an emergency descent of an aircraft, according to which method, when an automatic emergency descent function is engaged, the following successive operations are carried out:

a) a set of vertical directives is determined automatically, said directives comprising;

a target altitude which represents an altitude to be attained by the aircraft at the end of the emergency descent; and

a target speed which represents a speed that the aircraft must comply with during the emergency descent;

b) a set of lateral directives, which represents a lateral maneuver to be carried out during the emergency descent, is determined automatically; and

c) the aircraft is guided automatically so that it complies simultaneously with said set of vertical directives and said set of lateral directives until it attains said target altitude which it thereafter maintains, said automatic guidance possibly being interrupted by an action of a pilot of the aircraft,

according to which method, to automatically engage said emergency descent function, the following operations are carried out in an automatic manner;

α

1) a variation in altitude of the cabin of the aircraft, which depends on a variation in the pressure measured inside the cabin, is determined;

β

1) an engagement criterion which depends on said variation in altitude of the cabin is determined;

γ

1) this engagement criterion is compared with a predetermined threshold value; and

δ

1) said emergency descent function is engaged when said engagement criterion is above said threshold value,

wherein in step δ

1), said emergency descent function is engaged when said engagement criterion is above said threshold value for a predetermined duration, and in step a), the following operations are moreover carried out in an automatic manner;

in a step α

2);

a variation (Vpc) in the pressure of the air in the cabin is monitored; and

the size (T) of a hole in the structure of the aircraft, corresponding to structural damage, is estimated as a function of said variation (Vpc) in the pressure of the air in the cabin; and

in a step β

2), said target speed (Vc) is adapted to said estimated size (T) of the hole in the structure of the aircraft.

2. The method as claimed in claim 1, wherein said engagement criterion corresponds to said variation in altitude of the cabin.

3. The method as claimed in claim 1, wherein:

in step α

1), an altitude of the cabin of the aircraft, which depends on a pressure measured inside the cabin is moreover determined; and

in step β

1), an engagement criterion is determined as a function at one and the same time of said variation in altitude of the cabin and of said altitude of the cabin.

4. The method as claimed in claim 3, wherein in step β

1), one of the following engagement criteria x1, x2 and x3 is calculated;

5. The method as claimed in claim 1, wherein means (20) are provided allowing a pilot to manually engage said emergency descent function.

6. A device for the automatic control of an emergency descent of an aircraft, said device (1) comprising:

engagement means (2) able to engage an automatic emergency descent function;

means (7) for determining, automatically, a set of vertical directives comprising;

a target altitude which represents an altitude to be attained by the aircraft at the end of the emergency descent; and

a target speed which represents a speed that the aircraft must comply with during the emergency descent;

means (8) for determining, automatically, a set of lateral directives, which represents a lateral maneuver to be carried out during the emergency descent;

means (9) for automatically guiding the aircraft, upon engagement of an automatic emergency descent function, so that it complies simultaneously with said set of vertical directives and said set of lateral directives until it attains said target altitude which it thereafter maintains; and

means (5) allowing a pilot of the aircraft to manually interrupt said automatic guidance,

said engagement means (2) comprising, for automatically engaging said emergency descent function;

means (11) for automatically determining a variation in altitude of the cabin of the aircraft, which depends on a variation in the pressure measured inside the cabin;

means (12A, 12B) for automatically determining an engagement criterion which depends on said variation in altitude of the cabin;

means (14A, 14B) for automatically comparing this engagement criterion with a predetermined threshold value; and

means (17) for automatically ordering the engagement of said emergency descent function, when said engagement criterion is above said threshold value,

wherein said device comprises, moreover;

means (32) for automatically monitoring a variation (Vpc) in the pressure of the air in the cabin;

means (33) for automatically estimating the size (T) of a hole in the structure of the aircraft, corresponding to structural damage, as a function of said variation (Vpc) in the pressure of the air in the cabin; and

means (35) for automatically adapting the target speed (Vc) to said estimated size (T) of the hole in the structure of the aircraft.

7. An aircraft, which comprises a device (1) such as that specified under claim 6.