The present invention relates to a maintenance apparatus for a shock absorber of a landing gear, comprising a liquid reservoir which can be connected to an interior space of the shock absorber via a liquid line, a gas reservoir which can be connected to the interior space via a gas line, a coupling member for sealingly coupling the liquid reservoir and the gas reservoir, wherein the maintenance apparatus is configured to allow an exchange to occur of liquid and gas between the liquid reservoir and gas reservoir, respectively, and the interior space, the maintenance apparatus comprising control means for determining that a partial volume of the interior space occupied by the gas reaches a reference level as a result of the exchange and for bringing the partial volume of the interior space of the shock absorber respectively occupied by the gas and the liquid to a target level. The invention also relates to a maintenance method.

A hydraulic system 300 for an aircraft including a backup hydraulic pressure source 216 to provide hydraulic pressure to a brake 222 in the event of a failure condition of a primary hydraulic brake pressure source. The hydraulic system 300 also includes a landing gear backup system to provide hydraulic pressure to enable extension and/or retraction of landing gear 100. The backup hydraulic pressure source 216 is arranged to provide hydraulic pressure to the landing gear backup system in the event of a failure condition of a primary landing gear hydraulic pressure source.

A hydraulic system 300 for an aircraft including a backup hydraulic pressure source 216 to provide hydraulic pressure to a brake 222 in the event of a failure condition of a primary hydraulic brake pressure source. The hydraulic system 300 also includes a landing gear backup system to provide hydraulic pressure to enable extension and/or retraction of landing gear 100. The backup hydraulic pressure source 216 is arranged to provide hydraulic pressure to the landing gear backup system in the event of a failure condition of a primary landing gear hydraulic pressure source.

A method and apparatus for servicing a shock absorber on a landing gear assembly of an aircraft in a weight-on-wheels state is disclosed. The shock absorber includes at least one chamber containing both hydraulic fluid and a gas in fluid communication with each other. The apparatus includes a source of gas and a source of hydraulic fluid. The amount of hydraulic fluid in the chamber is corrected, preferably such that the chamber is then filled with a known amount of degassed hydraulic fluid. The process may be at least semi-automatically performed, for example under the control of a control unit. By delivering a pre-set mass of gas into the chamber, there is no need to rely on a measure of gas pressure or H-dimension (h) when servicing the shock absorber, and more accurate servicing of a shock absorber may thus be provided.

A method and apparatus for servicing a shock absorber on a landing gear assembly of an aircraft in a weight-on-wheels state is disclosed. The shock absorber includes at least one chamber containing both hydraulic fluid and a gas in fluid communication with each other. The apparatus includes a source of gas and a source of hydraulic fluid. The amount of hydraulic fluid in the chamber is corrected, preferably such that the chamber is then filled with a known amount of degassed hydraulic fluid. The process may be at least semi-automatically performed, for example under the control of a control unit. By delivering a pre-set mass of gas into the chamber, there is no need to rely on a measure of gas pressure or H-dimension (h) when servicing the shock absorber, and more accurate servicing of a shock absorber may thus be provided.

A method and portable apparatus for servicing a shock absorber on a landing gear assembly of an aircraft in a weight-on-wheels state is disclosed. The shock absorber includes at least one chamber containing both hydraulic fluid and a gas in fluid communication with each other. The apparatus includes a source of gas and a source of hydraulic fluid. The amount of hydraulic fluid in the chamber is corrected, preferably such that the chamber is then filled with a known amount of degassed hydraulic fluid. A pre-set mass of gas is then delivered into the chamber under the control of a gas delivery system of the portable apparatus. More accurate servicing of a shock absorber may thus be provided since account is additionally taken of gas dissolved in hydraulic fluid. By delivering a pre-set mass of gas into the chamber, there is no need to rely on a measure of gas pressure or H-dimension (h) when servicing the shock absorber.

A method and portable apparatus for servicing a shock absorber on a landing gear assembly of an aircraft in a weight-on-wheels state is disclosed. The shock absorber includes at least one chamber containing both hydraulic fluid and a gas in fluid communication with each other. The apparatus includes a source of gas and a source of hydraulic fluid. The amount of hydraulic fluid in the chamber is corrected, preferably such that the chamber is then filled with a known amount of degassed hydraulic fluid. A pre-set mass of gas is then delivered into the chamber under the control of a gas delivery system of the portable apparatus. More accurate servicing of a shock absorber may thus be provided since account is additionally taken of gas dissolved in hydraulic fluid. By delivering a pre-set mass of gas into the chamber, there is no need to rely on a measure of gas pressure or H-dimension (h) when servicing the shock absorber.

A device for connecting the elastic elements and dissipaters of variable type of a mechanical suspension interposed between two vibrating or tilting mechanical systems, the source body and the receiving body, respectively, in order to reduce the forces acting on the receiving body, and/or the displacement thereof, and/or the speed thereof, or combinations of the previous physical magnitudes and/or of any other ones, which are produced on the receiving body due to the motion or forces to which the source is subjected. The device consists of elastic elements, such as metal components or compressed gases, energy dissipating elements, either by means of friction between fluid and solid, and between solid and solid, or by means of suitable electromagnetic couplings the damping ability of which can be automatically varied by a suitable control system according to the operating conditions of the suspension; elements forming the kinematic connection structure between the elastic elements, damping elements, source and receiving bodies, such connections being solid or fluid or electromagnetic connections.

A device for connecting the elastic elements and dissipaters of variable type of a mechanical suspension interposed between two vibrating or tilting mechanical systems, the source body and the receiving body, respectively, in order to reduce the forces acting on the receiving body, and/or the displacement thereof, and/or the speed thereof, or combinations of the previous physical magnitudes and/or of any other ones, which are produced on the receiving body due to the motion or forces to which the source is subjected. The device consists of elastic elements, such as metal components or compressed gases, energy dissipating elements, either by means of friction between fluid and solid, and between solid and solid, or by means of suitable electromagnetic couplings the damping ability of which can be automatically varied by a suitable control system according to the operating conditions of the suspension; elements forming the kinematic connection structure between the elastic elements, damping elements, source and receiving bodies, such connections being solid or fluid or electromagnetic connections.

A main orifice plate assembly may be configured to transition a multi-actor damping system from a first damping actor configuration to a second damping actor configuration. The multi-actor damping system may be used in a shock strut assembly to alter a damping curve of the shuck strut assembly. The main orifice plate assembly may be a part of a main orifice assembly including an orbital cam. The main orifice plate may include a flow restrictor. The flow restrictor may be configured to retract or deploy in response to main orifice plate rotating about the orbital cam. The first damping actor configuration may correspond to a first damping curve. The second damping actor configuration may correspond to a second damping curve. The first damping curve being different than the second damping curve.