Method and a device for controlling the ground clearance of an aircraft

1. A method of controlling and adjusting the ground clearance ( h ) of an aircraft ( 1 ) provided with at least one undercarriage ( 30 ), said undercarriage ( 30 ) being provided with a damper-actuator ( 2 ) for performing a damping function and a function of retracting said undercarriage ( 30 ), wherein when the aircraft is on the ground, control means ( 10 ) automatically activate adjustment means ( 11 , 12 ) for continuously adjusting the length of said damper-actuator ( 2 ) in order to maintain said ground clearance ( h ) at a predetermined value, said control means also setting limits on said predetermined value for the ground clearance ( h ), said predetermined value being specified to the control means ( 10 ) via an interface ( 13 , 13 ′).

2. A method according to claim 1 , wherein for said control means ( 10 ) including a minimum safety value for ground clearance, if said predetermined value is less than said minimum safety value, then the control means ( 10 ) considers that said predetermined value is equal to said minimum safety value.

3. A method according to claim 1 , wherein for said control means ( 10 ) including a maximum safety value for ground clearance, if said predetermined value is greater than said maximum safety value, then the control means ( 10 ) considers that said predetermined value is equal to said maximum safety value.

4. A method according to claim 1 , wherein for a sensor ( 14 ) delivering a signal to the control means ( 10 ) representative of the current value of the ground clearance ( h ) of the aircraft ( 1 ), said control means ( 10 ) activate said adjustment means ( 11 , 12 ) in order to adjust the length of said damper-actuator ( 2 ) so that said current value of the ground clearance ( h ) reaches said predetermined value.

5. A method according to claim 4 , wherein said interface ( 13 ′) is independent of said control means ( 10 ).

6. A method according to claim 1 , wherein for a plurality of sensors ( 14 ) each sending a signal to the control means ( 10 ) representative of a local current value for the ground clearance ( h ) corresponding to a zone of the aircraft ( 1 ), said control means ( 10 ) perform processing on said signal to determine an overall current value for ground clearance and then activate said adjustment means ( 11 , 12 ) to adjust the length of said damper-actuator ( 2 ) so that said overall current value of the ground clearance ( h ) reaches said predetermined value.

7. A device for controlling and adjusting the ground clearance ( h ) of an aircraft ( 1 ) provided with at least one undercarriage ( 30 ), said undercarriage ( 30 ) being provided with a damper-actuator ( 2 ) for performing a damping function and a function of retracting said undercarriage, the device being provided with adjustment means ( 11 , 12 ) for adjusting the length of said damper-actuator ( 2 ) and with control means ( 10 ), said control means ( 10 ) continuously and automatically adjusting said length of said damper-actuator ( 2 ) via said adjustment means ( 11 , 12 ) so as to maintain said ground clearance ( h ) at a predetermined value, said control means further applying limits to said predetermined value.

8. A device according to claim 7 , including at least one sensor ( 14 ) for measuring said ground clearance ( h ).

9. A device according to claim 7 , wherein said adjustment means ( 11 , 12 ) comprises at least one solenoid valve for varying the quantity of a hydraulic liquid present in an outlet chamber ( 2 ′) of said damper-actuator ( 2 ).

10. A device according to claim 7 , wherein said control means ( 10 ) includes an interface ( 13 ) enabling an operator to specify said predetermined value.

11. A device according to claim 10 , wherein said interface ( 13 ) is integrated in said control means ( 10 ).

12. A device according to claim 10 , wherein for said interface ( 13 ) being remote, said interface ( 13 ) is connected to said control means ( 10 ) via a wired connection.

13. A device according to claim 10 , wherein for said interface ( 13 ) being remote, said interface ( 13 ) is connected to said control means ( 10 ) via a wireless connection.