Method and system for the automatic piloting of an aircraft on the approach to an airdrop position

• US 20050143904A1
• Filed: 12/03/2004
• Published: 06/30/2005
• Est. Priority Date: 12/04/2003
• Status: Active Grant

• Current Assignee: Airbus Operations SAS (Airbus SE)
• Original Assignee: Airbus France
• Inventors: Haas, Philippe
• Granted Patent: US 7,502,684 B2
• Time in Patent Office: Days
• US Class Current: 701/120
• CPC Class Codes: G05D 1/105 specially adapted for unpowered flight, e.g. glider, parachuting, forced landing parachutes per se B64D17/00

Abstract

Method and system for the automatic piloting of an aircraft on the approach to an airdrop position.

The system (1) comprises a means (2) for providing a speed profile that has to allow the aircraft to reach an airdrop position at a predetermined theoretical arrival time, with a predetermined speed, an automatic piloting device (3) for determining orders for piloting the aircraft so that it follows the speed profile, means of actuation (4) of controlled members (5) of the aircraft, to which the piloting orders are applied, a means (6) for determining an actual arrival time at which the aircraft will actually reach the airdrop position, and a means (8) for correcting the speed profile, as a function of the actual arrival time and of the theoretical arrival time, the speed profile thus corrected being provided to the automatic piloting device (3).

Claims

1. A method of automatic piloting of an aircraft during a phase of approach to a predetermined airdrop position ( 9), at which an airdrop is to be made from said aircraft, method according to which:

in the course of said approach phase, a speed profile (PV) with decreasing speed comprising a plurality of constant-speed levels (P1 to Pn), separated by deceleration phases (E1 to En), is applied automatically to the aircraft; and

the aircraft must reach said airdrop position (9) at a predetermined theoretical arrival time, with a predetermined speed,

wherein, in the course of said approach phase, automatically;

an actual arrival time at which the aircraft will actually reach said airdrop position (9) is determined;

the difference between said theoretical and actual arrival times is calculated; and

if this difference differs from zero;

said speed profile (PV) is corrected by modifying the length of at least two constant-speed levels in such a way as to cancel said difference; and

said speed profile (PVa, PVb, PVc) thus corrected is applied to said aircraft.

2. The method as claimed in claim 1,

wherein, when said actual arrival time is later than said theoretical arrival time, the length (L3) of at least one first level (P3) exhibiting a first constant speed (V3) is increased, and the length (L2) of at least one second level (P2) exhibiting a second constant speed (V2) is decreased, said first speed (V3) being greater than said second speed (V2).

3. The method as claimed in claim 2,

wherein said first level (P3) is increased and said second level (P2) is decreased by one and the same length xa which satisfies the following relation:

$\mathrm{xa}=<br><br>\frac{\mathrm{\Delta <br><br>}<br><br>\text{\hspace{1em}<br><br>}<br><br>t·<br><br>\mathrm{Vi}·<br><br>\mathrm{Vj}}{\left(\mathrm{Vj}-\mathrm{Vi}\right)}<br><br>$

in which;

Δ

t represents said time difference;

Vi represents said first constant speed; and

Vj represents said second constant speed.

4. The method as claimed in claim 1,

wherein, when said actual arrival time is earlier than said theoretical arrival time, the length (L3) of at least one first level (P3) exhibiting a first constant speed (V3) is decreased, and the length (L2) of at least one second level (P2) exhibiting a second constant speed (V2) is increased, said first speed (V3) being greater than said second speed (V2).

5. The method as claimed in claim 4,

wherein said first level (P 3) is decreased and said second level (P 2) is increased by one and the same length xb which satisfies the following relation:

$\mathrm{xb}=<br><br>\frac{\mathrm{\Delta <br><br>}<br><br>\text{\hspace{1em}<br><br>}<br><br>t·<br><br>\mathrm{Vi}·<br><br>\mathrm{Vj}}{\left(\mathrm{Vi}-\mathrm{Vj}\right)}<br><br>$

in which;

Δ

t represents said time difference;

Vi represents said first constant speed; and

Vj represents said second constant speed.

6. The method as claimed in claim 1,

wherein the length of more than two constant-speed levels is modified.

7. The method as claimed in claim 1,

wherein the length (Ln-1) of at least one constant-speed (Vn-1) level (Pn-1) is decreased completely in such a way as to eliminate this level (Pn-1).

12. An aircraft,

which comprises a system (1) able to implement the method specified under claim 1.

8. A system for the automatic piloting of an aircraft so as to pilot said aircraft at least during a phase of approach to a predetermined airdrop position (9), at which an airdrop is to be made from said aircraft, said system (1) comprising:

a first means ( 2) for providing a speed profile (PV) that has to allow the aircraft to reach said airdrop position ( 9) at a predetermined theoretical arrival time, with a predetermined speed;

an automatic piloting device (3) for determining orders for piloting the aircraft so that it follows said speed profile (PV); and

means of actuation (4) of controlled members (5) of the aircraft, to which said piloting orders are applied,

which system moreover comprises;

a second means (6) for determining an actual arrival time at which the aircraft will actually reach said airdrop position (9); and

a third means (8) for correcting said speed profile (PV), as a function of said actual arrival time and of said theoretical arrival time, the speed profile (PVa, PVb, PVc) thus corrected being provided to said automatic piloting device (3) to determine corresponding piloting orders which are applied to said means of actuation (4).

9. The system as claimed in claim 8,

wherein said first means (2) comprises a diskette (17), on which is recorded said speed profile (PV), and which can be read, with the aid of a means of reading (18), by said automatic piloting device (3).

10. The system as claimed in claim 8,

wherein said third means (8) is integrated into said automatic piloting device (3).

11. An aircraft,

which comprises a system (1) such as that specified under claim 8.