FR3057849A1 - METHOD FOR MAINTAINING AN IMMOBILE AIRCRAFT DURING GROUND DISPLACEMENT PHASES - Google Patents

Abstract

A method of immobilizing an aircraft equipped with undercarriages carrying wheels associated with actuators for rotating the wheels to move the aircraft to the ground, the method comprising the steps of: - causing the aircraft to stop in a given position; immobilizing the aircraft in this position by controlling the drive actuators so that they exert on the associated wheels a holding torque sufficient to keep the aircraft at a standstill.

Description

® FRENCH REPUBLIC

NATIONAL INSTITUTE OF INDUSTRIAL PROPERTY © Publication number:

(to be used only for reproduction orders)

©) National registration number

057 849

60305

COURBEVOIE © Int Cl ⁸ : B 64 C 25/44 (2017.01)

PATENT INVENTION APPLICATION

A1

©) Date of filing: 24.10.16. ©) Priority: © Applicant (s): SAFRAN LANDING SYSTEMS— FR. (© Inventor (s): ANAS FARID. ©) Date of public availability of the request: 04.27.18 Bulletin 18/17. ©) List of documents cited in the preliminary search report: See the end of this booklet (© References to other related national documents: ® Holder (s): SAFRAN LANDING SYSTEMS. ©) Extension request (s): © Agent (s): CABINET BOETTCHER.

£> 4 / METHOD FOR MAINTAINING A NON-MOVING AIRCRAFT DURING GROUND TRAVEL PHASES

FR 3,057,849 - A1 yV / Method for immobilizing an aircraft equipped with undercarriages carrying wheels associated with wheel rotation actuators for moving the aircraft on the ground, the method comprising the steps of:

- cause the aircraft to stop in a given position;

- immobilize the aircraft in this position by controlling the drive actuators so that they exert on the associated wheels a sufficient holding torque to keep the aircraft stationary.

i

The invention relates to a method for an aircraft during movement phases for immobilizing on the ground.

BACKGROUND OF THE INVENTION

Aircraft move on airport platforms between a door or a parking area and an airstrip. During these movements, the control tower often asks the pilot to immobilize the aircraft while waiting to be authorized to resume its movement. The pilot then maintains pressure on the brake pedals to ensure the immobility of the aircraft. If the immobilization lasts, the pilot can apply the parking brake, in order to release the effort on the pedals. This type of immobilization, however, requires brake disengages, thus guiding the brake actuators, whether they are hydraulic or electromechanical.

Aircraft equipped with wheel rotation actuators are also known to move the aircraft on the airport platform without using its propulsion units.

OBJECT OF THE INVENTION

The invention aims to propose a method of immobilizing an aircraft that does not apply the brakes for such an aircraft.

SUMMARY OF THE INVENTION

With a view to achieving this goal, a method of immobilizing an aircraft equipped with undercarriages carrying wheels associated with wheel rotation actuators for moving the aircraft on the ground is proposed according to the invention, the process comprising the steps of:

- cause the aircraft to stop in a given position;

- immobilize the aircraft in this position by controlling the drive actuators so that they exert on the associated wheels a holding torque sufficient to keep the aircraft stationary.

The stop may be caused by the use of the aircraft brakes. Then the aircraft is kept stationary thanks to the holding torque, and without the pilot having to maintain a pressure on the brake pedals or actuate the parking brake. Of course, it will be appropriate that the holding torque generated is sufficient to keep the aircraft stationary even if it is on a slope, or if it is subjected to wind.

A priori, the propulsion units are not used so that the holding torque does not have to be dimensioned to counter the effect of the residual thrust of the propulsion units. However, if it is provided that the method of the invention can be used while the propulsion units are in operation, it will be necessary to size the holding torque to counter the effect of the residual thrust of the propulsion units.

According to a first mode of implementation, the holding torque is generated by supplying the motors of the drives with sufficient to generate holding. Of course, this embodiment assumes that the current supply circuit of the drive actuators is active and capable of delivering such a current.

According to a second embodiment, the holding torque is generated by short-circuiting the phases of the motors of the drive actuators, after the aircraft has been stopped. It suffices to electrically connect the phases of a motor to obtain this short circuit, which can be done via the power electronics which control said electric motor.

effective current actuators the torque of

The advantages of the process of the invention are numerous:

- The brake discs are less stressed, which increases their service life, as well as that of the seals of the pistons of the brake actuators;

- The immobilization according to the invention requires only slightly the motors of the drive actuators, allowing them to contribute to the continuation of the movement after the immobilization phase;

- The immobilizer according to the invention can be completely automated, without even the pilot having to order it. It suffices to identify that the aircraft is stationary for a determined time (typically a few seconds), and to trigger the application of the holding torque according to the invention automatically, without intervention by the pilot.

Claims (3)

1. Method for immobilizing an aircraft equipped with undercarriages carrying wheels associated with actuators for driving the wheels in rotation to move the aircraft on the ground, the method comprising the steps of: - cause the aircraft to stop in a given position; - immobilize the aircraft in this position by controlling the drive actuators so that they exert on the associated wheels a holding torque sufficient to keep the aircraft stopped. 2. Method according to claim 1, in which the holding torque is generated by supplying the motors of the drive actuators with an effective current of sufficient intensity to generate the holding torque. 3. Method according to claim 1, in which the holding torque is generated by short-circuiting the phases of the motors of the drive actuators, after the aircraft has been stopped.