Hydraulic systems for shrinking landing gear shrink are described. An example apparatus includes a landing gear strut, a transfer cylinder, aircraft hydraulics, a pressure vessel, and a pressure-operated check valve. The landing gear strut has an outer cylinder and an inner cylinder movable relative to the outer cylinder between a first position and a second position. The landing gear strut has a first length when the inner cylinder is in the first position and a second length less than the first length when the inner cylinder is in the second position. The transfer cylinder exchanges hydraulic fluid with the landing gear strut. The aircraft hydraulics exchange hydraulic fluid with the transfer cylinder. The pressure vessel exchanges gas with the landing gear strut. The pressure-operated check valve controls an exchange of gas between the pressure vessel and the landing gear strut based on hydraulic fluid received from the aircraft hydraulics.

A shock strut for a vehicle includes a housing with a through channel and a motor mount, and a motor fixed to the housing. The cylinder of a shock strut is configured to define a lead screw on its outer surface. The cylinder extends through the housing. The piston of the shock strut is attached to a ground engaging assembly. A gear nut rotatably mounted in the housing threadably engages the threaded cylinder, and is configured to be driven by the motor. The housing is attached to the vehicle, and the gear nut is controllably rotated to extend and retract the shock strut. A sensor provided on the assembly monitors the position of the shock strut. A torsion link assembly reacts rotational forces on the cylinder.

A leg mechanism includes an articulated leg system, a passive device and a cable. The articulated leg system has a leg portion. The passive device is coupled to the articulated leg system and is configured to apply a first force to a portion thereof. The cable is coupled to the articulated leg system and is configured to apply a second force, in opposition to the first force, to a portion thereof. When the cable is drawn away from the articulated leg system, the second force moves the leg portion in a first direction. When tension is released from the cable, the passive device exerts the first force so as to move the leg portion a second direction that is opposite the first direction.

A landing gear (10) includes: a wheel support member (16) including a first portion for rollably supporting a wheel (14), and a second portion extending from the first portion toward a fuselage (12) in a direction of an axis of the first portion and supporting the first portion such that the first portion is rotatable about the axis; a swing support member for supporting the second portion of the wheel support member (16) such that the second portion is swingable relative to the fuselage (12); a retraction actuator (42) for swinging the wheel support member (16) to retract the wheel (14) into the fuselage (12) and deploy the wheel (14) from the fuselage (12); a brace (22) attached to the fuselage (12) and supporting the wheel support member (16); and a joint (20) connecting the brace (22) to the first portion of the wheel support member (16). The joint (20) is disposed closer to the wheel (14) than to the swing support member.

A landing gear assembly for use with an aircraft includes a housing including a trunnion brace, a drag brace, and an aft brace that together define an opening through the housing. The landing gear assembly also includes a shrink link assembly coupled to the housing such that the shrink link assembly is accessible through the opening.

A landing gear apparatus for an aircraft including at least a nose gear disposed forward of a neutral point of an aircraft by a first distance and at least a main gear disposed aft of the neutral point of the aircraft by a second distance. The at least a main gear are stored in at least a gear well that are at least located within the payload cabin.

An aerodynamic cover panel for a landing gear wheel well in an undercarriage of an aircraft includes at least one embodiment having a peripheral lip that defines a plane. Movements of the cover panel to open and close the wheel well are confined to pivotal rotation within the plane, and occur within an aerodynamic boundary layer of the undercarriage about a pivot axis in one rotational direction to open the wheel well, and in an opposite rotational direction to close the wheel well. The cover panel includes a flange, to which a rotary shaft is secured at one end for rotation about the pivot axis. The other end of the rotary shaft is secured to an actuator fixed within the undercarriage. In one embodiment, the cover panel rotates about an arc of least 75 between fully opened and fully closed positions of the wheel well.

A landing gear for an aircraft comprising a truck support strut, a landing gear retract mechanism coupling the truck support strut to a frame of the aircraft, so that the truck support strut is suspended from the frame by the landing gear retract mechanism, at least one wheel support arm rotatably coupled to the truck support strut, a carrier member coupled to the landing gear retract mechanism and to the truck support strut so that the landing gear retract mechanism drives the carrier member along the truck support strut, and at least one shock absorber, each of the at least one shock absorber being coupled to both a respective one of the at least one wheel support arm and the carrier member so that movement of the carrier member effects rotation of the at least one wheel support arm relative to the truck support strut.

A retractable landing gear includes a main strut having an upper end that is configured to connect to aircraft primary structure and a lower end configured to connect to an axle or bogie truck. An articulated stay has a distal end configured to connect to the aircraft structure and a proximal end pivotally connected to a cardan pin member. The cardan pin member has a cylindrical portion with a first recessed annular channel. The cardan pin member is retained in the socket by a ring assembly formed by two semi-annular ring members that slidably engages the first recessed channel. The ring assembly defines a second recessed annular channel. A collar is configured to be positioned over the second recessed channel, and to contract upon a change in temperature to lockingly engage the second recessed channel, to secure the split ring assembly in the first recessed channel.

A landing gear including a shock strut assembly including an outer cylinder coupled to an airframe, a wheel movably coupled to the outer cylinder so as to reciprocate substantially along a longitudinal axis of the outer cylinder, and a shrink mechanism including a pivot arm pivotally coupled to the shock strut assembly, a drive member coupling the pivot arm to a landing gear retract mechanism, a driven member coupled to the pivot arm, a first shrink link member coupled to the pivot arm by the driven member, and a second shrink link member coupled to the first shrink link member and to the shock strut assembly. Rotation of the pivot arm by the drive member, effects a folding movement between the first shrink link member and the second shrink link member, and the folding movement effects at least a retraction of the wheel relative to the outer cylinder.