Abstract: A landing gear for a vehicle includes a strut configured for reciprocating movement between a stowed position and a deployed position. A shock absorber has a first element slidingly disposed within the strut and a second element slidingly coupled to the first element. A trailing arm is rotatably coupled to the second element. A first linkage is coupled to the first element, wherein the first linkage drives the first element between a raised position when the strut is in the stowed position and a lowered position when the strut is in the deployed position. The landing gear further includes a second linkage coupled to the trailing arm. The second linkage rotates the trailing arm between a first trailing arm position when the strut is in the stowed position and a second trailing arm position when the strut is in the deployed position.

Abstract: Wheel acceleration systems are disclosed that provide a motive force to at least one wheel of an aircraft, in order to accelerate the aircraft to takeoff speed with the assistance of main engine thrust. The wheel acceleration system includes a pyrotechnic unit configured to generate expanding gases by combusting a propellant, and a rotary propulsion unit pneumatically coupled to the pyrotechnic unit. The rotary propulsion unit includes an impeller configured to be driven by the expanding gases and to deliver torque to the wheel.

Abstract: A shock absorber includes a housing and an end wall slidably disposed within the housing. The end wall and the housing cooperate to define at least a portion of a cavity within the housing. The cavity is filled with a fluid, and a piston is slidably disposed within the cavity. Movement of the piston within the cavity compresses the fluid to provide a spring force. The shock absorber further includes a compensator coupled to the end wall. The compensator positions the end wall within the housing to change a volume of the cavity in response to a change in a temperature of a first element of the compensator.

Abstract: A landing gear system includes a drive shaft extending through an axle. A wheel with a drive surface is rotatably coupled to the axle. A drive assembly, which has disengaged and engaged states, includes a drive element and an idler element. The drive element, which has an engagement feature, is coupled to the drive shaft for rotation about an axis. The engagement feature has first and second diameters when the drive assembly is in the disengaged and engaged states, respectively. The idler element is frictionally engaged with the engagement feature of the drive element to transfer rotation of the drive element to the wheel when the drive assembly is in the engaged state. The idler element is disengaged from at least one of the engagement feature of drive element and the wheel when the drive assembly is in the disengaged state.

Abstract: A landing gear system includes wheel rotatably coupled to an axle. A driveshaft extends through a cavity formed in the axle and is rotatable about an axis. A planetary gear includes a sun gear operably coupled to the drive shaft and a planet gear operably engaging the sun gear. The planetary gear further includes a ring gear that surrounds and is operably coupled to the planet gear so that rotation of the drive shaft rotates the ring gear. A clutch assembly is selectively moveable between an engaged state and a disengaged state. The clutch assembly transfers rotation of the ring gear to the wheel when the clutch assembly is in the engaged state, and the clutch assembly does not transfer rotation of the wheel to the ring gear when the clutch assembly is in the disengaged state.

Abstract: A shock absorber includes a housing and an end wall slidably disposed within the housing. The end wall and the housing cooperate to define at least a portion of a cavity within the housing. The cavity is filled with a fluid, and a piston is slidably disposed within the cavity. Movement of the piston within the cavity compresses the fluid to provide a spring force. The shock absorber further includes a compensator coupled to the end wall. The compensator positions the end wall within the housing to change a volume of the cavity in response to a change in a temperature of a first element of the compensator.

Abstract: Techniques and methodologies for servicing a shock strut are provided that account for the variability in gas solubility of the shock strut while in-service. These examples incorporates knowledge of the shock strut's stoke history in order to estimate/predict the amount of gas in solution, its percentage saturation, etc. This may permit a more refined knowledge of the true servicing state of the shock strut.

Abstract: A remote towing interface is used to couple a towbar to an aircraft having a fuselage and a steerable landing gear. The remote towing interface includes a towbar coupler mounted to the aircraft and configured to releasably couple a towbar to the aircraft. The remote towing interface further includes a sensor and a controller. The sensor is configured to sense a position of the towbar relative to the aircraft when the towbar is coupled to the towbar coupler, and the controller controls the steerable landing gear according to the sensed position of the towbar relative to the aircraft.

Abstract: A landing gear for a vehicle includes a strut configured for reciprocating movement between a stowed position and a deployed position. A shock absorber has a first element slidingly disposed within the strut and a second element slidingly coupled to the first element. A trailing arm is rotatably coupled to the second element. A first linkage is coupled to the first element, wherein the first linkage drives the first element between a raised position when the strut is in the stowed position and a lowered position when the strut is in the deployed position. The landing gear further includes a second linkage coupled to the trailing arm. The second linkage rotates the trailing arm between a first trailing arm position when the strut is in the stowed position and a second trailing arm position when the strut is in the deployed position.

Abstract: A landing gear system includes a wheel rotatably coupled to an axle about an axis. A torque tube is rotatably mounted to the axle about the axis such that the axle extends through a central portion of the torque tube. A rotor is fixed in rotation about the axis relative to the wheel, and a stator is fixed in rotation about the axis relative to the torque tube. The landing gear assembly further includes a clutch assembly selectively reciprocal between an engaged state and a disengaged state. The stator is fixed in rotation about the axis relative to the torque tube when the clutch assembly is in an engaged state. When the clutch assembly is in a disengaged state, the stator is rotatably about the axis relative to the torque tube.

Abstract: A thermal actuator includes a piston slidingly within a cylinder. The piston cooperates with the cylinder to define a cavity. The piston also includes a rod extending away from the cavity. A magnetic field generator selectively imparts an alternating magnetic field to the cylinder, and inductively heats a heating element mounted within the cavity. The cavity also includes a volume of a phase-change material, which is melted by the heating element. The melting phase-change material expands to drive the rod from a retracted position to an extended position.

Abstract: A landing gear system includes a wheel rotatably coupled to the axle about an axis. A motor is fixedly positioned relative to the axle with a clutch assembly operably coupled to an output shaft of the motor. The landing gear includes an actuator and a drive assembly. The actuator applies a braking force to the wheel. The drive assembly includes a pinion gear and a drive gear rotatably associated with the pinion gear. The drive gear is configured to transfer a rotational force to the wheel in order to provide autonomous taxiing capability. Both the brake assembly and the drive assembly are operably coupled to the clutch assembly so that the output shaft of the motor drives both the brake assembly and the drive assembly.

Abstract: A taxi drive system is disclosed that provides motive force to wheels of an aircraft. The motive force is transferred by a motor powered continuous track (e.g., belt, chain, or other flexible transmission element) directly to the wheel(s) of an aircraft. The system is carried by the landing gear of the aircraft, and is placed in engagement with an aircraft wheel with sufficient force to allow for the track to drive the aircraft wheel. The taxi drive system includes a separate motor from the main aircraft engines so that the aircraft may be taxied while the main engines are shutdown or at idle.

Abstract: A thermal actuator includes a piston slidingly within a cylinder. The piston cooperates with the cylinder to define a cavity. The piston also includes a rod extending away from the cavity. A magnetic field generator selectively imparts an alternating magnetic field to the cylinder, and inductively heats a heating element mounted within the cavity. The cavity also includes a volume of a phase-change material, which is melted by the heating element. The melting phase-change material expands to drive the rod from a retracted position to an extended position.

Abstract: A landing gear system includes an axle having an internal cavity and a wheel rotatably coupled to the axle. A drive shaft is mounted within the cavity to be rotatable about an axis. The landing gear system further includes a rod slidably mounted within the drive shaft and a clutch. The clutch has a first portion that is coupled to the rod and rotates with the drive shaft. A second portion of the clutch is fixedly coupled to the wheel. The rod selectively reciprocates along the axis between a first position and a second position to engage and disengage the clutch.

Abstract: A bushing is configured for installation in the hole of a lug, which has a protrusion extending radially inward from a surface of the hole. The bushing includes a first cylindrical body that is sized to be received within the hole of the lug. A flange extends radially outward from one end of the first cylindrical body, and a first recess is formed in the first cylindrical body to a radial face. The recess is sized and configured to receive the protrusion of the lug when the bushing is installed in the hole. Engagement of the protrusion with the recess preventing movement of the bushing relative to the lug.

Abstract: An aircraft landing gear assembly having a main strut pivotally coupled to an aircraft, a bogie beam pivotally connected to the main strut, a first axle mounted at the first end of the bogie beam and arranged to carry one or more first wheel assemblies and brake assemblies, each first brake assembly being attached to the bogie beam by a brake rod, and a second axle mounted at a second end of the bogie beam and arranged to carry one or more second wheel assemblies and brake assemblies. A double acting actuator is coupled between the strut and the bogie beam to apply a compressive or tensile force to the bogie beam. The ends of the bogie beam are arranged to position the bogie pivot axis below a plane intersecting the axes of rotation of the first and second wheel assemblies when the strut is in the deployed condition.

Abstract: An aircraft landing gear bogie beam including first and second ends and a mounting bearing for connection to an aircraft landing gear main strut between the ends. Each end has a respective axle, and each axle defines a wheel mounting portion on each side of the bogie beam. The bogie beam is arranged to enable the first and second axles to each pivot relative to the bearing about a respective longitudinal axis of the bogie beam by an amount that is sufficient to place a wheel rim of a wheel assembly in contact with the ground in the event of a tyre of the wheel assembly deflating.

Abstract: An aircraft landing gear bogie beam including first and second ends and a mounting bearing for connection to an aircraft landing gear main strut between the ends. Each end has a respective axle, and each axle defines a wheel mounting portion on each side of the bogie beam. The bogie beam is arranged to enable the first and second axles to each pivot relative to the bearing about a respective longitudinal axis of the bogie beam by an amount that is sufficient to place a wheel rim of a wheel assembly in contact with the ground in the event of a tyre of the wheel assembly deflating.

Abstract: An aircraft assembly having landing gear with a known deployment value, apparatus for permitting landing gear deployment, down-lock sensing apparatus, a navigation system, a landing gear control system, a flight control system, and a deployment controller. The deployment controller is configured to: calculate a touch down value using the aircraft position and speed information provided by the aircraft navigation system; command the landing gear control system to provide the deploy signal when the touch down value reaches a deployment threshold value which is greater than the landing gear deployment value; and command the flight control system to execute a landing abort sequence if the controller does not receive the down-lock signal from the landing gear sensing apparatus within a deployment value window which is greater than or equal to the known deployment value for the landing gear but less than the touch down value.