Retraction actuator assembly, landing gear assembly and method of kneeling landing gear assembly of aircraft

Abstract

The invention relates to a retraction actuator assembly, a landing gear assembly, and a method of kneeling an aircraft landing gear assembly. A retraction actuator assembly for a landing gear assembly of an aircraft includes a retraction actuator and a kneeling stop assembly. The retraction actuator includes an actuator housing and a piston. The actuator housing includes a cylinder barrel along a longitudinal axis. The piston is disposed within the cylinder barrel and is configured to move within the cylinder barrel. The cylinder barrel defines a piston stroke having an extended piston position and a retracted piston position. The kneeling stop assembly is secured to the actuator housing. The kneeling stop assembly is configured to selectively establish a kneeling stop position within the cylinder barrel to reduce the piston stroke by inhibiting movement of the piston to the retracted piston position. The landing gear assembly includes the retraction actuator, the kneeling stop assembly, a trailing arm, and a shock absorber. A method of kneeling a landing gear assembly of an aircraft is also provided.

Description

Technical Field

[0001] The present disclosure relates generally to techniques for kneeling a landing gear assembly of an aircraft, and more particularly to the use of a retract actuator assembly that provides the landing gear assembly with a third position between an extended position and a retracted position that can be used to lower the aircraft to a kneeling condition for certain ground operations. Background Art

[0002] Some aircraft feature landing gear that has the ability to lower (i.e., kneel) the aircraft when the aircraft is on the ground. It is desirable to kneel the aircraft to facilitate crew and / or passenger entry / exit, to facilitate cargo loading / unloading, and to lower the height of the aircraft during transportation and storage. Existing designs typically use some form of external kneeling mechanism to move the landing gear to the kneeling position. These concepts typically require additional hydraulic actuators and additional mechanical linkages, which can increase cost, complexity, and weight.

[0003] Accordingly, those skilled in the art continue to conduct research and development efforts to improve the techniques for kneeling landing gear assemblies of aircraft. Summary of the invention

[0004] Examples of retracting actuator assemblies, landing gear assemblies, and methods of kneeling landing gear assemblies of an aircraft are disclosed.The following is a non-exhaustive list of examples according to the subject matter of the present disclosure, which may or may not be claimed.

[0005] In one example, a retraction actuator assembly for a landing gear assembly of an aircraft is disclosed, comprising a retraction actuator and a knee stop assembly. The retraction actuator comprises an actuator housing and a piston. The actuator housing defines a longitudinal axis extending through a distal end and a proximal end. The actuator housing comprises a cylinder barrel along the longitudinal axis. The piston is disposed in the cylinder barrel and is configured to move along the longitudinal axis in the cylinder barrel. The cylinder barrel defines a piston stroke in the actuator housing, and the piston stroke limits the movement of the piston. The piston stroke comprises an extended piston position associated with the distal end of the actuator housing and a retracted piston position associated with the proximal end of the actuator housing. The knee stop assembly is fixed to the outer surface of the actuator housing relative to the extended piston position in the cylinder barrel and the retracted piston position in the cylinder barrel. The knee stop assembly is configured to selectively establish a knee stop position in the cylinder barrel to reduce the piston stroke by inhibiting the movement of the piston to the retracted piston position.

[0006] In one example, a landing gear assembly for an aircraft is disclosed that includes a retracting actuator, a kneeling stop assembly, a trailing arm, and a shock absorber. The retracting actuator includes an actuator housing and a piston. The actuator housing defines a longitudinal axis extending through a distal end and a proximal end. The actuator housing includes a cylinder barrel along the longitudinal axis. The piston is disposed in the cylinder barrel and is configured to move along the longitudinal axis in the cylinder barrel. The cylinder barrel defines a piston stroke in the actuator housing, and the piston stroke limits the movement of the piston. The piston stroke includes an extended piston position associated with the distal end of the actuator housing and a retracted piston position associated with the proximal end of the actuator housing. The kneeling stop assembly is fixed to an outer surface of the actuator housing relative to the extended piston position in the cylinder barrel and the retracted piston position in the cylinder barrel. The kneeling stop assembly is configured to selectively establish a kneeling stop position in the cylinder barrel to reduce the piston stroke by inhibiting the movement of the piston to the retracted piston position. The trailing arm includes an arm proximal end and an arm distal end. The distal end of the arm is configured to be pivotally attached to a fixed point on the aircraft. The proximal end of the arm is configured to be attached to the surface contact assembly. The shock absorber is mechanically connected to the retraction actuator and is configured to be pivotally attached to the trailing arm.

[0007] A method for kneeling a landing gear assembly of an aircraft is disclosed. In one example, the disclosed method includes: (1) performing an aircraft ground operation in which the landing gear assembly is in a fully extended state and a retraction actuator of the landing gear assembly is in an extended piston position; (2) activating a kneeling feature of the landing gear assembly to establish a kneeling stop position in the retraction actuator, the kneeling stop position reducing a piston stroke of the retraction actuator by inhibiting movement of a piston in the retraction actuator beyond the kneeling stop position toward a retraction piston position; and (3) moving the landing gear assembly from the fully extended state to the kneeling stop state by moving the retraction actuator from the extended piston position to the kneeling stop position.

[0008] Clause 1. A retraction actuator assembly (100) for a landing gear assembly (102) of an aircraft (2400), the retraction actuator assembly (100) comprising:

[0009] A retracting actuator (104) comprising:

[0010] an actuator housing (202) defining a longitudinal axis (204) extending through a distal end (206) and a proximal end (208), the actuator housing (202) including a cylinder barrel (210) along the longitudinal axis (204); and

[0011] A piston (212) is disposed in the cylinder barrel (210) and is configured to

[0012] The cylinder barrel (210) is movable along the longitudinal axis (204) within the actuator housing (202), the cylinder barrel (210) defining a piston stroke (214) within the actuator housing (202), the piston stroke (214) limiting the movement of the piston (212), the piston stroke (214) including an extended piston position (216) associated with the distal end (206) of the actuator housing (202) and a retracted piston position (218) associated with the proximal end (208) of the actuator housing (202); and

[0013] A kneeling stop assembly (106) is fixed to an outer surface (220) of the actuator housing (202) relative to the extended piston position (216) within the cylinder barrel (210) and the retracted piston position (218) within the cylinder barrel (210), the kneeling stop assembly (106) being configured to selectively establish a kneeling stop position (302) within the cylinder barrel (210) to reduce the piston stroke (214) by inhibiting movement of the piston (212) toward the retracted piston position (218).

[0014] Clause 2. The retract actuator assembly of clause 1, further comprising:

[0015] A shock absorber (108) is fixed to the proximal end (208) of the actuator housing (202) such that the shock absorber (108) and the retract actuator (104) are aligned along the longitudinal axis (204) of the actuator housing (202) to form an in-line shock absorber actuator (110), the shock absorber (108) being configured to be pivotally attached to a trailing arm (112) of the landing gear assembly (102).

[0016] Clause 3. The retract actuator assembly of clause 1, wherein the piston (212) defines a rod chamber (222) in the cylinder barrel (210) associated with the distal end (206) of the actuator housing (202) and defines a piston chamber (224) in the cylinder barrel (210) associated with the proximal end (208) of the actuator housing (202), the retract actuator (104) further comprising:

[0017] A piston rod (226) is disposed within the rod chamber (222) and includes a first end (228) attached to the piston (212) and a second end (230) extending through a sealed bore (232) at the distal end (206) of the actuator housing (202).

[0018] Clause 4. The retraction actuator assembly of clause 3, wherein the second end (230) of the piston rod (226) is configured to be pivotally attached to a fixed point on the aircraft (2400), the retraction actuator assembly (100) further comprising:

[0019] A shock absorber (108) is secured to the proximal end (208) of the actuator housing (202) such that the shock absorber (108) and the retract actuator (104) are aligned along the longitudinal axis (204) of the actuator housing (202) to form an in-line shock absorber actuator (110), the shock absorber (108) being configured to be pivotally attached to a trailing arm (112) of the landing gear assembly (102).

[0020] Clause 5. The retraction actuator assembly of clause 4, wherein the mechanical linkage of the landing gear assembly (102) comprises a trailing arm (112) of the landing gear assembly (102) and the inline shock absorber actuator (110).

[0021] Clause 6. The retract actuator assembly of clause 3, wherein the proximal end (208) of the actuator housing (202) is configured to be pivotally attached to a fixed point on the aircraft (2400), the retract actuator assembly (100) further comprising:

[0022] A shock absorber (108) is mechanically linked to the second end (230) of the piston rod (226), the shock absorber (108) being configured to be pivotally attached to a trailing arm (112) of the landing gear assembly (102).

[0023] Clause 7. A retraction actuator assembly according to Clause 6, wherein the mechanical linkage device of the landing gear assembly (102) includes a trailing arm (112) of the landing gear assembly (102), the shock absorber (108), the retraction actuator (104), and a connecting member (1202) located between the retraction actuator (104) and the shock absorber (108).

[0024] Clause 8. The retract actuator assembly of clause 3, wherein the retract actuator (104) further comprises:

[0025] a rod hydraulic port (234) disposed near the distal end (206) of the actuator housing (202) to provide fluid access to the rod chamber (222); and

[0026] A piston hydraulic port (236) is disposed near the proximal end (208) of the actuator housing (202) to provide fluid access to the piston chamber (224).

[0027] Clause 9. A retract actuator assembly according to clause 1, wherein the piston stroke (214) and the extended piston position (216) within the cylinder barrel (210) are related to the fully extended state (1002) of the landing gear assembly (102) and the landing sequence of the aircraft (2400).

[0028] Clause 10. The retraction actuator assembly of clause 1, wherein the retraction piston position (218) within the cylinder barrel (210) of the piston stroke (214) is related to a fully retracted state (802) of the landing gear assembly (102) and a takeoff sequence of the aircraft (2400).

[0029] Clause 11. The retraction actuator assembly of clause 1, wherein the kneeling stop position (302) of the piston stroke (214) within the cylinder barrel (210) is associated with a kneeling state (602) of the landing gear assembly (102) during ground operation of the aircraft (2400).

[0030] Clause 12. A retract actuator assembly according to clause 1, wherein the kneeling stop assembly (106) is configured to allow the piston (212) to move within the cylinder barrel (210) from the kneeling stop position (302) of the piston stroke (214) to the extended piston position (216).

[0031] Clause 13. A retraction actuator assembly according to clause 1, wherein the kneeling stop assembly (106) is configured to selectively remove the kneeling stop position (302) of the piston stroke (214) within the cylinder barrel (210) to allow the piston (212) to move to the retracted piston position (218) of the piston stroke (214).

[0032] Clause 14. The retract actuator assembly of clause 1, wherein the kneeling stop assembly (106) comprises:

[0033] a kneeling stop housing (1102) fixed to the outer surface (220) of the actuator housing (202) of the retract actuator (104) relative to the extend piston position (216) within the cylinder barrel (210) and the retract piston position (218) within the cylinder barrel (210) of the retract actuator (104), the kneeling stop housing (1102) including a kneeling stop distal end (1104) closer to the distal end (206) of the actuator housing (202) and a kneeling stop proximal end (1106) closer to the proximal end (208) of the actuator housing (202), the kneeling stop housing (1102) defining a cavity (304) between an inner surface (306) of the kneeling stop housing (1102) and the outer surface (220) of the actuator housing (202);

[0034] a kneeling stop insertion port (308) disposed on the kneeling stop housing (1102) to provide fluid access to a kneeling stop insertion chamber (310) formed within the cavity (304); and

[0035] A kneeling stop retraction port (312) is disposed on the kneeling stop housing (1102) to provide fluid access to a kneeling stop retraction chamber (314) formed within the cavity (304).

[0036] Clause 15. A retraction actuator assembly according to clause 14, wherein the kneeling stop insertion port (308) is configured to receive pressurized fluid from a pressurized fluid source, and the kneeling stop assembly (106) is configured to establish the kneeling stop position (302) in response to receipt of the pressurized fluid at the kneeling stop insertion port (308).

[0037] Clause 16. The retract actuator assembly of Clause 15, wherein the pressurized fluid comprises at least one of pressurized hydraulic fluid, pressurized oil, compressed gas, and compressed air.

[0038] Clause 17. A retraction actuator assembly according to clause 15, wherein the kneeling stop insertion port (308) is configured to allow the pressurized fluid to leave the kneeling stop assembly (106) after the pressurized fluid source is no longer applying the pressurized fluid, and the kneeling stop assembly (106) is configured such that the exit of the pressurized fluid through the kneeling stop insertion port (308) does not affect the current state of the kneeling stop position (302).

[0039] Clause 18. A retraction actuator assembly according to clause 14, wherein the kneeling stop retraction port (312) is configured to receive pressurized fluid from a pressurized fluid source, and the kneeling stop assembly (106) is configured to remove the kneeling stop position (302) in response to receipt of the pressurized fluid at the kneeling stop retraction port (312).

[0040] Clause 19. A retraction actuator assembly according to clause 18, wherein the kneeling stop retraction port (312) is configured to allow the pressurized fluid to leave the kneeling stop assembly (106), and the kneeling stop assembly (106) is configured so that the exit of the pressurized fluid through the kneeling retraction port (312) does not affect the current state of the kneeling stop position (302).

[0041] Clause 20. The retract actuator assembly of clause 14, wherein the kneeling stop assembly (106) further comprises:

[0042] At least one kneeling stop segment (1108) is arranged in the cavity (304) of the kneeling stop housing (1102) at a predetermined point (1109) along the longitudinal axis (204) of the actuator housing (202), and the predetermined point (1109) is associated with the kneeling stop position (302), the actuator housing (202) includes at least one kneeling stop hole (1110) extending through the actuator housing (202) to the cylinder barrel (210), and the at least one kneeling stop hole (1110) is configured to receive at least a portion of the at least one kneeling stop segment (1108), and the at least one kneeling stop segment (1108) is configured to be selectively inserted into the at least one kneeling stop hole (1110) and is configured to be selectively removed from the at least one kneeling stop hole (1110).

[0043] Clause 21. A retraction actuator assembly according to clause 20, wherein the at least one kneeling stop segment (1108) includes at least two kneeling stop segments (1108) radially distributed around the actuator housing (202) at the predetermined point (1109), and wherein the at least one kneeling stop hole (1110) includes at least two kneeling stop holes (1110) radially distributed around the actuator housing (202) relative to the at least two kneeling stop segments (1108).

[0044] Clause 22. According to the retraction actuator assembly described in Clause 20, the at least one kneeling stop segment (1108) of the kneeling stop assembly (106) includes at least one of two kneeling stop segments, three kneeling stop segments, four kneeling stop segments, five kneeling stop segments and six kneeling stop segments, and accordingly, the at least one kneeling stop hole (1110) of the retraction actuator (104) includes at least one of two kneeling stop holes, three kneeling stop holes, four kneeling stop holes, five kneeling stop holes and six kneeling stop holes.

[0045] Clause 23. A retraction actuator assembly according to clause 20, wherein the kneeling stop insertion port (308) is configured to receive a pressurized fluid from a pressurized fluid source, and the kneeling stop assembly (106) is configured to insert the at least one kneeling stop segment (1108) into the at least one kneeling stop hole (1110) of the actuator housing (202) in response to the receipt of the pressurized fluid at the kneeling stop insertion port (308) to establish the kneeling stop position (302).

[0046] Clause 24. A retraction actuator assembly according to clause 20, wherein the kneeling stop retraction port (312) is configured to receive a pressurized fluid from a pressurized fluid source, and the kneeling stop assembly (106) is configured to retract the at least one kneeling stop segment (1108) from the at least one kneeling stop hole (1110) of the actuator housing (202) in response to receipt of the pressurized fluid at the kneeling stop retraction port (312) to remove the kneeling stop position (302).

[0047] Clause 25. The retract actuator assembly of clause 20, wherein the kneeling stop assembly (106) further comprises:

[0048] an upper biasing member (1112) disposed within the cavity (304) between the kneeling stop housing (1102) and the actuator housing (202) and proximate the kneeling stop distal end (1104) of the kneeling stop housing (1102);

[0049] an upper sliding member (1114) disposed within the cavity (304) between the kneeling stop housing (1102) and the actuator housing (202) and between the upper biasing member (1112) and the at least one kneeling stop segment (1108), the upper sliding member (1114) comprising a first portion of an upper sliding member outer surface (1116) facing the inner surface (306) of the kneeling stop housing (1102), the first portion of the upper sliding member outer surface (1116) and a corresponding portion of the inner surface (306) of the kneeling stop housing (1102) being configured to form the kneeling stop insertion chamber (310), the upper biasing member (1112) being configured to bias the upper sliding member (1114) toward the at least one kneeling stop segment (1108);

[0050] a lower biasing member (1118) disposed within the cavity (304) between the kneeling stop housing (1102) and the actuator housing (202) and proximate the kneeling stop proximal end (1106) of the kneeling stop housing (1102); and

[0051] A lower sliding member (1120) is arranged in the cavity (304) between the kneeling stop shell (1102) and the actuator shell (202) and between the at least one kneeling stop segment (1108) and the lower biasing member (1118), the lower sliding member (1120) including a first portion of the outer surface (1122) of the lower sliding member facing the inner surface (306) of the kneeling stop shell (1102), the first portion of the outer surface (1122) of the lower sliding member and a relative portion of the inner surface (306) of the kneeling stop shell (1102) being configured to form the kneeling stop retraction chamber (314), and the lower biasing member (1118) being configured to bias the lower sliding member (1120) toward the at least one kneeling stop segment (1108).

[0052] Clause 26. The retraction actuator assembly of clause 25, wherein the upper slide member (1114) further comprises:

[0053] a second portion of the upper slide outer surface (1116) in relative geometric relationship with the upper surface of the at least one kneeling stop segment (1108); and

[0054] a third portion of the upper slider outer surface (1116) adjacent to a corresponding portion of the outer surface (220) of the actuator housing (202),

[0055] wherein the second portion of the upper slide outer surface (1116) rises from the third portion of the upper slide outer surface (1116) to the first portion of the upper slide outer surface (1116) at a predetermined angle to facilitate retracting the at least one kneeling stop segment (1108) from the at least one kneeling stop hole (1110) of the actuator housing (202),

[0056] Wherein the first portion of the upper slide outer surface (1116) and the third portion of the upper slide outer surface (1116) are configured to slide between the at least one kneeling stop segment (1108) and the outer surface (220) of the actuator housing (202) in response to the application of pressure at the kneeling stop retraction port (312) to prevent the at least one kneeling stop segment (1108) from being inserted into the at least one kneeling stop hole (1110).

[0057] Clause 27. The retraction actuator assembly of clause 25, wherein the lower slide member (1120) further comprises:

[0058] a second portion of the lower slide outer surface (1122) in relative geometric relationship with the lower surface of the at least one kneeling stop segment (1108); and

[0059] a third portion of the lower slide outer surface (1122) adjacent to a corresponding portion of the inner surface (306) of the kneeling stop housing (1102),

[0060] wherein the second portion of the lower slide outer surface (1122) descends from the first portion of the lower slide outer surface (1122) to the third portion of the lower slide outer surface (1122) at a predetermined angle to facilitate insertion of the at least one kneeling stop segment (1108) into the at least one kneeling stop hole (1110) of the actuator housing (202),

[0061] Wherein the first portion of the lower sliding member outer surface (1122) and the third portion of the lower sliding member outer surface (1122) are configured to slide between the at least one kneeling stop segment (1108) and the inner surface (306) of the kneeling stop shell (1102) in response to the application of pressure at the kneeling stop insertion port (308) to prevent the at least one kneeling stop segment (1108) from retracting from the at least one kneeling stop hole (1110).

[0062] Clause 28. A retraction actuator assembly according to clause 25, wherein the kneeling stop plug-in port (308) is configured to receive pressurized fluid from a pressurized fluid source and provide the pressurized fluid to the kneeling stop insertion chamber (310), wherein the kneeling stop assembly (106) is configured to move the upper sliding member (1114) toward the upper biasing member (1112) and away from the at least one kneeling stop segment (1108) in response to the kneeling stop insertion chamber (310) receiving the pressurized fluid, wherein the kneeling stop assembly (106) is configured to move the upper sliding member (1114) toward the upper biasing member (1112) and away from the at least one kneeling stop segment (1108) in response to the upper sliding member (1114) moving away from the at least one kneeling stop segment (1108) and the lower biasing member (1118) toward the At least one kneeling stop segment (1108) biases the lower sliding member (1120) to move the lower sliding member (1120) toward the at least one kneeling stop segment (1108), wherein the kneeling stop assembly (106) is configured to insert the at least one kneeling stop segment (1108) into the at least one kneeling stop hole (1110) of the actuator housing (202) in response to the lower sliding member (1120) moving toward the at least one kneeling stop segment (1108) and pushing the at least one kneeling stop segment (1108) into the at least one kneeling stop hole (1110) to establish the kneeling stop position (302) within the cylinder barrel (210) of the retracting actuator (104).

[0063] Clause 29. A retraction actuator assembly according to clause 28, wherein after the at least one kneeling stop segment (1108) of the kneeling stop assembly (106) is inserted into the at least one kneeling stop hole (1110) of the actuator housing (202), the lower biasing member (1118), the lower sliding member (1120) and the at least one kneeling stop segment (1108) are configured so that the lower sliding member (1120) is moved to a locked position, wherein the locked position maintains the at least one kneeling stop segment (1108) inserted into the at least one kneeling stop hole (1110) with or without pressure applied to the kneeling stop insertion port (308) until pressure is applied to the kneeling stop retraction port (312).

[0064] Clause 30. A retraction actuator assembly according to clause 25, wherein the kneeling stop retraction port (312) is configured to receive pressurized fluid from a pressurized fluid source and provide the pressurized fluid to the kneeling stop retraction chamber (314), wherein the kneeling stop assembly (106) is configured to move the lower sliding member (1120) toward the lower biasing member (1118) and away from the at least one kneeling stop segment (1108) in response to the kneeling stop retraction chamber (314) receiving the pressurized fluid, wherein the kneeling stop assembly (106) is configured to move the lower sliding member (1120) toward the lower biasing member (1118) and away from the at least one kneeling stop segment (1108) in response to the lower sliding member (1120) moving away from the at least one kneeling stop segment (1108) and the upper biasing member (1112) The sliding member (1114) is biased toward the at least one kneeling stop segment (1108) to move the upper sliding member (1114) toward the at least one kneeling stop segment (1108), wherein the kneeling stop assembly (106) is configured to retract the at least one kneeling stop segment (1108) from the at least one kneeling stop hole (1110) of the actuator housing (202) in response to the upper sliding member (1114) moving toward the at least one kneeling stop segment (1108) and pushing the at least one kneeling stop segment (1108) away from the at least one kneeling stop hole (1110) to remove the kneeling stop position (302) from the cylinder barrel (210) of the retracting actuator (104).

[0065] Clause 31. A retraction actuator assembly according to clause 30, wherein after the at least one kneeling stop segment (1108) of the kneeling stop assembly (106) is retracted from the at least one kneeling stop hole (1110) of the actuator housing (202), the upper biasing member (1112), the upper sliding member (1114) and the at least one kneeling stop segment (1108) are configured so that the upper sliding member (1114) is moved to a locked position, wherein the locked position maintains the at least one kneeling stop segment (1108) retracted from the at least one kneeling stop hole (1110) with or without pressure applied to the kneeling stop retraction port (312) until pressure is applied to the kneeling stop insertion port (308).

[0066] Clause 32. A landing gear assembly (102) for an aircraft (2400), the landing gear assembly (102) comprising:

[0067] A retracting actuator (104) comprising:

[0068] an actuator housing (202) defining a longitudinal axis (204) extending through a distal end (206) and a proximal end (208), the actuator housing (202) including a cylinder barrel (210) along the longitudinal axis (204);

[0069] and

[0070] A piston (212) is disposed in the cylinder barrel (210) and is configured to

[0071] The cylinder barrel (210) is movable along the longitudinal axis (204) within the actuator housing (202), the cylinder barrel (210) defining a piston stroke (214) within the actuator housing (202), the piston stroke (214) defining a range of motion of the piston (212), the piston stroke (214) including an extended piston position (216) associated with the distal end (206) of the actuator housing (202) and a retracted piston position (218) associated with the proximal end (208) of the actuator housing (202);

[0072] a kneeling stop assembly (106) fixed to an outer surface (220) of the actuator housing (202) relative to the extended piston position (216) within the cylinder barrel (210) and the retracted piston position (218) within the cylinder barrel (210), the kneeling stop assembly (106) being configured to selectively establish a kneeling stop position (302) within the cylinder barrel (210) to reduce the piston stroke (214) by inhibiting movement of the piston (212) toward the retracted piston position (218);

[0073] a trailing arm (112) comprising an arm proximal end (114) and an arm distal end (116), the arm distal end (116) being configured to be pivotally attached to a fixed point on the aircraft (2400), the arm proximal end (114) being configured to be attached to a surface contact assembly (118); and

[0074] A shock absorber (108) is mechanically linked to the retraction actuator (104) and is configured to be pivotally attached to the trailing arm (112).

[0075] Clause 33. A landing gear assembly according to clause 32, wherein the shock absorber (108) is fixed to the proximal end (208) of the actuator housing (202) so that the shock absorber (108) and the retraction actuator (104) are aligned along the longitudinal axis (204) of the actuator housing (202) to form an in-line shock absorber actuator (110).

[0076] Clause 34. The landing gear assembly of clause 32, wherein the piston (212) defines a rod chamber (222) in the cylinder barrel (210) associated with the distal end (206) of the actuator housing (202) and defines a piston chamber (224) in the cylinder barrel (210) associated with the proximal end (208) of the actuator housing (202), the retraction actuator (104) further comprising:

[0077] A piston rod (226) is disposed within the rod chamber (222) and includes a first end (228) attached to the piston (212) and a second end (230) extending through a sealed bore (232) at the distal end (206) of the actuator housing (202).

[0078] Clause 35. A landing gear assembly according to clause 34, wherein the second end (230) of the piston rod (226) is configured to be pivotally attached to a second fixed point on the aircraft (2400), and the shock absorber (108) is fixed to the proximal end (208) of the actuator housing (202) so that the shock absorber (108) and the retraction actuator (104) are aligned along the longitudinal axis (204) of the actuator housing (202) to form an in-line shock absorber actuator (110).

[0079] Clause 36. The landing gear assembly of clause 35, wherein the mechanical linkage of the landing gear assembly (102) includes the trailing arm (112) and the inline shock absorber actuator (110).

[0080] Clause 37. A landing gear assembly according to clause 34, wherein the second end (230) of the piston rod (226) in the retraction actuator (104) is mechanically linked to the shock absorber (108), and the proximal end (208) of the actuator housing (202) is configured to be pivotally attached to a second fixed point on the aircraft (2400).

[0081] Clause 38. A landing gear assembly according to clause 37, wherein the mechanical linkage device of the landing gear assembly (102) includes the trailing arm (112), the shock absorber (108), the retraction actuator (104), and a connecting member (1202) located between the retraction actuator (104) and the shock absorber (108).

[0082] Clause 39. The landing gear assembly of clause 34, wherein the retraction actuator (104) further comprises:

[0083] a rod hydraulic port (234) disposed near the distal end (206) of the actuator housing (202) to provide fluid access to the rod chamber (222); and

[0084] A piston hydraulic port (236) is disposed near the proximal end (208) of the actuator housing (202) to provide fluid access to the piston chamber (224).

[0085] Clause 40. The landing gear assembly of Clause 32, wherein the surface contacting assembly (118) comprises at least one of a wheel and a skid.

[0086] Clause 41. A landing gear assembly according to clause 32, wherein the extended piston position (216) of the piston stroke (214) within the cylinder barrel (210) is related to the fully extended state (1002) of the landing gear assembly (102) and the landing sequence of the aircraft (2400).

[0087] Clause 42. A landing gear assembly according to clause 32, wherein the retracted piston position (218) of the piston stroke (214) within the cylinder barrel (210) is related to a fully retracted state (802) of the landing gear assembly (102) and a takeoff sequence of the aircraft (2400).

[0088] Clause 43. A landing gear assembly according to clause 32, wherein the kneeling stop position (302) of the piston stroke (214) within the cylinder barrel (210) is associated with a kneeling state (602) of the landing gear assembly (102) during ground operation of the aircraft (2400).

[0089] Clause 44. A landing gear assembly according to clause 32, wherein the kneeling stop assembly (106) is configured to allow the piston (212) to move within the cylinder barrel (210) from the kneeling stop position (302) of the piston stroke (214) to the extended piston position (216).

[0090] Clause 45. A landing gear assembly according to clause 32, wherein the kneeling stop assembly (106) is configured to selectively remove the kneeling stop position (302) of the piston stroke (214) within the cylinder barrel (210) to allow the piston (212) to move to the retracted piston position (218) of the piston stroke (214).

[0091] Clause 46. The landing gear assembly of clause 32, wherein the kneeling stop assembly (106) comprises:

[0092] a kneeling stop housing (1102) fixed to the outer surface (220) of the actuator housing (202) of the retract actuator (104) relative to the extend piston position (216) within the cylinder barrel (210) and the retract piston position (218) within the cylinder barrel (210) of the retract actuator (104), the kneeling stop housing (1102) including a kneeling stop distal end (1104) closer to the distal end (206) of the actuator housing (202) and a kneeling stop proximal end (1106) closer to the proximal end (208) of the actuator housing (202), the kneeling stop housing (1102) defining a cavity (304) between an inner surface (306) of the kneeling stop housing (1102) and the outer surface (220) of the actuator housing (202);

[0093] a kneeling stop insertion port (308) disposed on the kneeling stop housing (1102) to provide fluid access to a kneeling stop insertion chamber (310) formed within the cavity (304); and

[0094] A kneeling stop retraction port (312) is disposed on the kneeling stop housing (1102) to provide fluid access to a kneeling stop retraction chamber (314) formed within the cavity (304).

[0095] Clause 47. The landing gear assembly of clause 46, wherein the kneeling stop assembly (106) further comprises:

[0096] At least one kneeling stop segment (1108) is arranged in the cavity (304) of the kneeling stop housing (1102) at a predetermined point (1109) along the longitudinal axis (204) of the actuator housing (202), and the predetermined point (1109) is associated with the kneeling stop position (302), the actuator housing (202) includes at least one kneeling stop hole (1110) extending through the actuator housing (202) to the cylinder barrel (210), and the at least one kneeling stop hole (1110) is configured to receive at least a portion of the at least one kneeling stop segment (1108), and the at least one kneeling stop segment (1108) is configured to be selectively inserted into the at least one kneeling stop hole (1110) and is configured to be selectively removed from the at least one kneeling stop hole (1110).

[0097] Clause 48. A landing gear assembly according to Clause 47, wherein the at least one kneeling stop segment (1108) includes at least two kneeling stop segments (1108) radially distributed around the actuator housing (202) at the predetermined point (1109), and wherein the at least one kneeling stop hole (1110) includes at least two kneeling stop holes (1110) radially distributed around the actuator housing (202) relative to the at least two kneeling stop segments (1108).

[0098] Clause 49. The landing gear assembly of clause 47, wherein the kneeling stop assembly (106) further comprises:

[0099] an upper biasing member (1112) disposed within the cavity (304) between the kneeling stop housing (1102) and the actuator housing (202) and proximate the kneeling stop distal end (1104) of the kneeling stop housing (1102);

[0100] an upper sliding member (1114) disposed within the cavity (304) between the kneeling stop housing (1102) and the actuator housing (202) and between the upper biasing member (1112) and the at least one kneeling stop segment (1108), the upper sliding member (1114) comprising a first portion of an upper sliding member outer surface (1116) facing the inner surface (306) of the kneeling stop housing (1102), the first portion of the upper sliding member outer surface (1116) and a corresponding portion of the inner surface (306) of the kneeling stop housing (1102) being configured to form the kneeling stop insertion chamber (310), the upper biasing member (1112) being configured to bias the upper sliding member (1114) toward the at least one kneeling stop segment (1108);

[0101] a lower biasing member (1118) disposed within the cavity (304) between the kneeling stop housing (1102) and the actuator housing (202) and proximate the kneeling stop proximal end (1106) of the kneeling stop housing (1102); and

[0102] A lower sliding member (1120) is arranged in the cavity (304) between the kneeling stop shell (1102) and the actuator shell (202) and between the at least one kneeling stop segment (1108) and the lower biasing member (1118), the lower sliding member (1120) including a first portion of the outer surface (1122) of the lower sliding member facing the inner surface (306) of the kneeling stop shell (1102), the first portion of the outer surface (1122) of the lower sliding member and a relative portion of the inner surface (306) of the kneeling stop shell (1102) being configured to form the kneeling stop retraction chamber (314), and the lower biasing member (1118) being configured to bias the lower sliding member (1120) toward the at least one kneeling stop segment (1108).

[0103] Clause 50. A method (1300) of kneeling a landing gear assembly (102) of an aircraft (2400), the method (1300) comprising:

[0104] performing (1302) a ground operation on an aircraft (2400) wherein the landing gear assembly (102) is in a fully extended state (1002) and a retract actuator (104) of the landing gear assembly (102) is in an extended piston position (216);

[0105] activating (1304) a kneeling feature of the landing gear assembly (102) to establish a kneeling stop position (302) in the retract actuator (104), the kneeling stop position (302) reducing a piston stroke (214) of the retract actuator (104) by inhibiting movement of a piston (212) in the retract actuator (104) beyond the kneeling stop position (302) toward a retract piston position (218); and

[0106] The landing gear assembly (102) is moved (1306) from the fully extended state (1002) to a kneeled state (602) by moving the retraction actuator (104) from the extended piston position (216) to the kneeled stop position (302).

[0107] Clause 51. A method according to clause 50, wherein the piston stroke (214) and the extension piston position (216) within the cylinder barrel (210) of the retraction actuator (104) are related to the fully extended state (1002) of the landing gear assembly (102) and the landing sequence of the aircraft (2400).

[0108] Clause 52. A method according to clause 50, wherein the piston stroke (214) and the retract piston position (218) within the cylinder barrel (210) of the retract actuator (104) are related to the fully retracted state (802) of the landing gear assembly (102) and the takeoff sequence of the aircraft (2400).

[0109] Clause 53. A method according to clause 50, wherein the kneeling stop position (302) of the piston stroke (214) within the cylinder barrel (210) of the retraction actuator (104) is associated with the kneeling state (602) of the landing gear assembly (102) during ground operation of the aircraft (2400).

[0110] Clause 54. The method according to clause 50, further comprising:

[0111] The landing gear assembly (102) is moved (1308) from the kneeling state (602) to the fully extended state (1002) by moving the retract actuator (104) from the kneeling stop position (302) to the extend piston position (216) while the kneeling feature of the landing gear assembly (102) is still enabled.

[0112] Clause 55. The method (1400) of clause 50, further comprising:

[0113] The kneeling stop position (302) is established (1402) in the retract actuator (104) in response to receiving pressurized fluid from a pressurized fluid source at a kneeling stop insertion port (308) of a kneeling stop assembly (106) secured to an outer surface (220) of the retract actuator (104).

[0114] Clause 56. The method according to clause 55, further comprising:

[0115] After the pressurized fluid source is no longer applying the pressurized fluid, the pressurized fluid is allowed (1404) to exit the kneeling stop assembly (106) via the kneeling stop insertion port (308) without affecting the current state of the kneeling stop position (302).

[0116] Clause 57. The method (1500) of clause 50, further comprising:

[0117] In response to receiving pressurized fluid from a pressurized fluid source at a kneeling stop insertion port (308) of the kneeling stop assembly (106), the kneeling stop position (302) is established (1502) in the retract actuator (104) by inserting at least one kneeling stop segment (1108) of the kneeling stop assembly (106) fixed to an outer surface (220) of the retract actuator (104) into at least one kneeling stop hole (1110) extending through the outer surface (220) to a cylinder barrel (210) of the retract actuator (104).

[0118] Clause 58. The method (1600) of clause 50, further comprising:

[0119] The kneeling stop position (302) is established (1602) in the retract actuator (104) by:

[0120] In response to receiving pressurized fluid from a pressurized fluid source at a kneeling stop insertion chamber (310) of the kneeling stop assembly (106) via a kneeling stop insertion port (308) of the kneeling stop assembly (106), an upper sliding member (1114) of the kneeling stop assembly (106) fixed to an outer surface (220) of the retract actuator (104) is moved toward and away from an upper biasing member (1112) of the kneeling stop assembly (106). at least one kneeling stop segment (1108) of the kneeling stop assembly (106) moves (1604), wherein after the upper slide member (1114) moves toward the upper biasing member (1112), the at least one kneeling stop segment (1108) is no longer locked and is free to move laterally between the inner surface (306) of the kneeling stop housing (1102) and the outer surface (220) of the retract actuator (104);

[0121] in response to the upper sliding member (1114) moving away from the at least one kneeling stop segment (1108), causing the lower sliding member (1120) of the kneeling stop assembly (106) to move toward the at least one kneeling stop segment (1108), the at least one kneeling stop segment (1108) being free to move laterally and the lower biasing member (1118) biasing the lower sliding member (1120) toward the at least one kneeling stop segment (1108); and

[0122] In response to the lower sliding member (1120) moving toward the at least one kneeling stop segment (1108) and the relative conical surface of the lower sliding member (1120) pushing the at least one kneeling stop segment (1108) into the at least one kneeling stop hole (1110), the at least one kneeling stop segment (1108) is inserted into the at least one kneeling stop hole (1110) extending through the outer surface (220) to the cylinder barrel (210) of the retraction actuator (104) to establish the kneeling stop position (302) within the cylinder barrel (210) of the retraction actuator (104).

[0123] Clause 59. The method (1700) of clause 58, further comprising:

[0124] locking (1702) the kneeling stop position (302) in the retract actuator (104) after the at least one kneeling stop segment (1108) of the kneeling stop assembly (106) is inserted into the at least one kneeling stop hole (1110) of the actuator housing (202); and

[0125] The at least one kneeling stop segment (1108) is maintained (1704) inserted into the at least one kneeling stop hole (1110) with or without pressure applied to the kneeling stop insertion port (308) until pressure is applied to the kneeling stop retraction port (312) of the kneeling stop assembly (106).

[0126] Clause 60. The method (1800) of clause 50, further comprising:

[0127] deactivating (1802) the kneeling feature of the landing gear assembly (102) to remove the kneeling stop position (302) from the retract actuator (104) to allow the piston (212) to move to the retract piston position (218) of the piston stroke (214);

[0128] initiating (1804) a takeoff sequence of the aircraft (2400) wherein the landing gear assembly (102) is in the fully extended state (1002) and the retract actuator (104) of the landing gear assembly (102) is in the extend piston position (216); and

[0129] The takeoff sequence is completed (1806) and a flight operation of the aircraft (2400) is performed with the landing gear assembly (102) in a fully retracted state (802) and the retract actuator (104) in the retract piston position (218).

[0130] Clause 61. The method (1900) of clause 60, further comprising:

[0131] The kneeling stop position (302) is removed (1902) from the retract actuator (104) in response to receiving pressurized fluid from a pressurized fluid source at a kneeling stop retraction port (312) of a kneeling stop assembly (106) secured to an outer surface (220) of the retract actuator (104).

[0132] Clause 62. The method according to clause 61, further comprising:

[0133] After the pressurized fluid source is no longer applying the pressurized fluid, the pressurized fluid is allowed (1904) to exit the kneeling stop assembly (106) via the kneeling stop retract port (312) without affecting the current state of the kneeling stop position (302).

[0134] Clause 63. The method (2000) of clause 60, further comprising:

[0135] In response to receiving pressurized fluid from a pressurized fluid source at a kneeling stop retraction port (312) of the kneeling stop assembly (106), the kneeling stop position (302) is removed (2002) from the retract actuator (104) by retracting at least one kneeling stop segment (1108) of the kneeling stop assembly (106) secured to an outer surface (220) of the retract actuator (104) from at least one kneeling stop hole (1110) extending through the outer surface (220) to a cylinder barrel (210) of the retract actuator (104).

[0136] Clause 64. The method (2100) of clause 60, further comprising:

[0137] The kneeling stop position (302) is removed (2102) from the retract actuator (104) by:

[0138] In response to receiving pressurized fluid from a pressurized fluid source at a kneeling stop retract chamber (314) of the kneeling stop assembly (106) via a kneeling stop retract port (312) of the kneeling stop assembly (106), a lower sliding member (1120) of the kneeling stop assembly (106) fixed to an outer surface (220) of the retract actuator (104) is moved toward and away from a lower biasing member (1118) of the kneeling stop assembly (106). at least one kneeling stop segment (1108) of the kneeling stop assembly (106) moves (2104), wherein after the lower slide member (1120) moves toward the lower biasing member (1118), the at least one kneeling stop segment (1108) is no longer locked and is free to move laterally between the inner surface (306) of the kneeling stop housing (1102) and the outer surface (220) of the retract actuator (104);

[0139] in response to the lower sliding member (1120) moving away from the at least one kneeling stop segment (1108), causing the upper sliding member (1114) of the kneeling stop assembly (106) to move toward the at least one kneeling stop segment (1108), the at least one kneeling stop segment (1108) being free to move laterally and the upper biasing member (1112) biasing the upper sliding member (1114) toward the at least one kneeling stop segment (1108); and

[0140] In response to the upper sliding member (1114) moving toward the at least one kneeling stop segment (1108) and the relative conical surface of the upper sliding member (1114) pushing the at least one kneeling stop segment (1108) away from the at least one kneeling stop hole (1110), the at least one kneeling stop segment (1108) is retracted (2108) from the at least one kneeling stop hole (1110) extending through the outer surface (220) to the cylinder barrel (210) of the retract actuator (104) to be retracted from the cylinder barrel (210) of the retract actuator (104)

[0141] The kneeling stop position (302) is removed.

[0142] Clause 65. The method (2200) of clause 64, further comprising:

[0143] locking out (2202) activation of the kneeling stop position (302) in the retracting actuator (104) after the at least one kneeling stop segment (1108) of the kneeling stop assembly (106) is retracted from the at least one kneeling stop hole (1110) of the actuator housing (202); and

[0144] The at least one kneeling stop segment (1108) is maintained (2204) retracted from the at least one kneeling stop hole (1110) with or without pressure applied to the kneeling stop retraction port (312) until pressure is applied to the kneeling stop insertion port (308) of the kneeling stop assembly (106).

[0145] Other examples of the disclosed retraction actuator assembly, landing gear assembly, and method of kneeling an aircraft landing gear assembly will become apparent from the following detailed description, drawings, and appended claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0146] Figure 1 is a functional diagram illustrating an example of a retraction actuator assembly for an example aircraft landing gear assembly;

[0147] Figure 2 is used for Figure 1 a cross-sectional view of an example of a retract actuator of a retract actuator assembly;

[0148] Figure 3 is used for Figure 1 a cross-sectional view of an example of a kneeling stop assembly of a retract actuator assembly with the kneeling stop segment inserted into the retract actuator and the retract actuator in an extended position;

[0149] Figure 4 It is shown Figure 1 a functional diagram of the landing gear assembly with the landing gear in the extended position and the weight of the aircraft on the wheels;

[0150] Figure 5 is used for Figure 1 a cross-sectional view of an example of a kneeling stop assembly of a retract actuator assembly with the kneeling stop segment inserted into the retract actuator and the retract actuator in the kneeling stop position;

[0151] Figure 6 It is shown Figure 1 Functional diagram of the landing gear assembly with the landing gear in kneeling position and the weight of the aircraft on the wheels;

[0152] Figure 7 is used for Figure 1 a cross-sectional view of an example of a kneeling stop assembly of a retract actuator assembly with the kneeling stop segment retracted from the retract actuator and the retract actuator in a retracted position;

[0153] Figure 8 It is shown Figure 1 a functional diagram of the landing gear assembly with the landing gear in a retracted position and the aircraft in flight;

[0154] Fig. 9 is used for Figure 1 a cross-sectional view of an example of a kneeling stop assembly of a retract actuator assembly with the kneeling stop segment retracted from the retract actuator and the retract actuator in an extended position;

[0155] Fig.10 It is shown Figure 1 a functional diagram of the landing gear assembly with the landing gear in an extended position and the aircraft in flight;

[0156] Fig.11 It is about Figure 1 Example of a retract actuator of a retract actuator assembly Figure 3 an exploded view of an example of a kneeling stop assembly;

[0157] Fig. 12A is a functional diagram showing another example of a landing gear assembly, wherein the landing gear is in an extended state and the weight of the aircraft is on the wheels;

[0158] Fig. 12B It is shown Fig. 12A Functional diagram of the landing gear assembly with the landing gear in kneeling position and the weight of the aircraft on the wheels;

[0159] Fig. 12C It is shown Fig. 12A a functional diagram of the landing gear assembly with the landing gear in a retracted position and the aircraft in flight;

[0160] Fig.13 A flow chart of an example of a method of kneeling a landing gear assembly of an aircraft is provided;

[0161] Fig.14 Combination Fig.13 is a flow chart of another example of a method of kneeling a landing gear assembly of an aircraft;

[0162] Fig.15 Combination Fig.13 is a flow chart of yet another example of a method of kneeling a landing gear assembly of an aircraft;

[0163] Fig.16 Combination Fig.13 is a flow chart of yet another example of a method of kneeling a landing gear assembly of an aircraft;

[0164] Fig.17 Combination Fig.13 and Fig.16 is a flow chart of yet another example of a method of kneeling a landing gear assembly of an aircraft;

[0165] Fig.18 Combination Fig.13 is a flow chart of another example of a method of kneeling a landing gear assembly of an aircraft;

[0166] Fig.19 Combination Fig.13 and Fig.18 is a flow chart of yet another example of a method of kneeling a landing gear assembly of an aircraft;

[0167] Fig. 20 Combination Fig.13 and Fig.18 is a flow chart of yet another example of a method of kneeling a landing gear assembly of an aircraft;

[0168] Fig.21 Combination Fig.13 and Fig.18 is a flow chart of yet another example of a method of kneeling a landing gear assembly of an aircraft;

[0169] Fig. 22 Combination Fig.13 , Fig.18 and Fig.21 is a flow chart of yet another example of a method of kneeling a landing gear assembly of an aircraft;

[0170] Fig.23 is a block diagram of an aircraft production and service method that implements one or more examples of the method disclosed herein for kneeling a landing gear assembly of an aircraft; and

[0171] Fig.24 is a schematic diagram of an aircraft incorporating one or more examples of the retraction actuator assembly and landing gear assembly disclosed herein. DETAILED DESCRIPTION

[0172] Various examples of retracting actuator assemblies, landing gear assemblies, and methods of kneeling a landing gear assembly of an aircraft provide techniques that allow the retracting actuator assembly to have a third position between an extended position and a retracted position that can be used to lower an aircraft to a kneeling state when the aircraft is on the ground. This kneeling actuator position is provided using a retractable stop that limits the stroke of the actuator piston when engaged. These stops are inserted and retracted using a mechanism in a housing mounted on the outer diameter of the actuator. The mechanism includes a series of slip rings and springs. This mechanism requires external activation (e.g., hydraulic pressure) to change state (i.e., from retracted to inserted or from inserted to retracted), but once in the retracted or inserted position, the mechanism is self-locking.

[0173] The internal self-locking kneeling mechanism provides several advantages over previous kneeling methods. For example, the landing gear assembly does not require an auxiliary kneeling actuator. In the case of an in-line shock absorber / actuator, the mechanism does not reduce the length of the in-line shock absorber / actuator and results in lower loads on the in-line shock absorber / actuator. The mechanism has limited hydraulic shock because the fluid volume required for kneeling is low. The mechanism is implemented using a compact design that requires fewer structural interfaces. In addition, the dedicated kneeling mechanism is not within the landing load path, thereby improving reliability and reducing part weight.

[0174] Overall reference Figure 1-Figure 11 , Figure 12A-12C as well as Fig.24 For example, the present disclosure relates to a retraction actuator assembly 100 for a landing gear assembly 102 of an aircraft 2400 . Figure 1 An example of a retract actuator assembly 100 is disclosed. Figure 2 Shown for Figure 1 A cross-sectional view of an example of a retract actuator 104 of the retract actuator assembly 100 . Figure 3 Shown for Figure 1 A cross-sectional view of an example of a kneeling stop assembly 106 of a retract actuator assembly 100 with a kneeling stop segment 1108 inserted into the retract actuator 104 and the retract actuator 104 in an extended position. Figure 4 Show Figure 1 2400 is a functional diagram of landing gear assembly 102 with landing gear assembly 102 in an extended state and the weight of aircraft 2400 is on the wheels. Figure 5 Shown for Figure 1 1 is a cross-sectional view of an example of a kneeling stop assembly 106 of a retract actuator assembly 100 with a kneeling stop segment 1108 inserted into the retract actuator 104 and the retract actuator 104 in a kneeling position.

[0175] Figure 6 Shows Figure 1 2400 is a functional diagram of the landing gear assembly 102, wherein the landing gear assembly 102 is in a kneeling position and the weight of the aircraft 2400 is on the wheels. Figure 7 Shown for Figure 1 1 is a cross-sectional view of an example of a kneeling stop assembly 106 of a retract actuator assembly 100 with the kneeling stop segment 1108 retracted from the retract actuator 104 and the retract actuator 104 in a retracted position. Figure 8 Shows Figure 1 2400 is a functional diagram of landing gear assembly 102 with landing gear assembly 102 in a retracted state and aircraft 2400 in flight. Fig. 9 Shown for Figure 11 is a cross-sectional view of an example of a kneeling stop assembly 106 of a retract actuator assembly 100 with the kneeling stop segment 1108 retracted from the retract actuator 104 and the retract actuator 104 in an extended position. Fig.10 Shows Figure 1 2400 is a functional diagram of landing gear assembly 102 with landing gear assembly 102 in an extended state and aircraft 2400 in flight. Fig.11 Provide information about Figure 1 Example of a retract actuator 104 of the retract actuator assembly 100 Figure 3 An exploded view of an example of a kneeling stop assembly 106 .

[0176] Fig. 12A Another example of landing gear assembly 102 is disclosed, wherein landing gear assembly 102 is in an extended state and the weight of aircraft 2400 is on the wheels. Fig. 12B Shows Fig. 12A 2400 is a functional diagram of the landing gear assembly 102, wherein the landing gear assembly 102 is in a kneeling position and the weight of the aircraft 2400 is on the wheels. Fig. 12C Shows Fig. 12A 2400 is a functional diagram of landing gear assembly 102 with landing gear assembly 102 in a retracted state and aircraft 2400 in flight. Fig.24 An aircraft 2400 is shown incorporating one or more examples of the retract actuator assembly 100 disclosed herein.

[0177] Reference again Figure 1-Figure 11 , Figure 12A-12C as well as Fig.24In one or more examples, a retraction actuator assembly 100 for a landing gear assembly 102 of an aircraft 2400 includes a retraction actuator 104 and a kneeling stop assembly 106. The retraction actuator 104 includes an actuator housing 202 and a piston 212. The actuator housing 202 defines a longitudinal axis 204 extending through a distal end 206 and a proximal end 208. The actuator housing 202 includes a cylinder barrel 210 along the longitudinal axis 204. The piston 212 is disposed within the cylinder barrel 210 and is configured to move within the cylinder barrel 210 along the longitudinal axis 204. The cylinder barrel 210 defines a piston stroke 214 within the actuator housing 202, and the piston stroke 214 limits the movement of the piston 212. The piston stroke 214 includes an extended piston position 216 associated with the distal end 206 of the actuator housing 202 and a retracted piston position 218 associated with the proximal end 208 of the actuator housing 202. The kneeling stop assembly 106 is fixed to the outer surface 220 of the actuator housing 202 relative to the extended piston position 216 within the cylinder barrel 210 and the retracted piston position 218 within the cylinder barrel 210. The kneeling stop assembly 106 is configured to selectively establish a kneeling stop position 302 within the cylinder barrel 210 to reduce the piston stroke 214 by inhibiting movement of the piston 212 toward the retracted piston position 218.

[0178] In another example, the retraction actuator assembly 100 further includes a shock absorber 108 fixed to a proximal end 208 of the actuator housing 202 such that the shock absorber 108 and the retraction actuator 104 are aligned along a longitudinal axis 204 of the actuator housing 202 to form an inline shock absorber actuator 110. The shock absorber 108 is configured to be pivotally attached to a trailing arm 112 of the landing gear assembly 102.

[0179] In yet another example of the retract actuator assembly 100, the piston 212 defines a rod chamber 222 in the cylinder barrel 210 associated with the distal end 206 of the actuator housing 202 and a piston chamber 224 in the cylinder barrel 210 associated with the proximal end 208 of the actuator housing 202. In this example, the retract actuator 104 also includes a piston rod 226 disposed within the rod chamber 222. The piston rod 226 includes a first end 228 attached to the piston 212 and a second end 230 extending through a sealed bore 232 at the distal end 206 of the actuator housing 202.

[0180] In a further example, the second end 230 of the piston rod 226 is configured to be pivotally attached to a fixed point on the aircraft 2400. In this example, the retraction actuator assembly 100 also includes a shock absorber 108 fixed to the proximal end 208 of the actuator housing 202 such that the shock absorber 108 and the retraction actuator 104 are aligned along the longitudinal axis 204 of the actuator housing 202 to form an inline shock absorber actuator 110. The shock absorber 108 is configured to be pivotally attached to the trailing arm 112 of the landing gear assembly 102. In a further example, the mechanical linkage of the landing gear assembly 102 includes the trailing arm 112 of the landing gear assembly 102 and the inline shock absorber actuator 110.

[0181] In yet a further example, the proximal end 208 of the actuator housing 202 is configured to be pivotally attached to a fixed point on the aircraft 2400. In this example, the retract actuator assembly 100 also includes a shock absorber 108 mechanically linked to the second end 230 of the piston rod 226. The shock absorber 108 is configured to be pivotally attached to the trailing arm 112 of the landing gear assembly 102. In yet a further example, the mechanical linkage of the landing gear assembly 102 includes the trailing arm 112 of the landing gear assembly 102, the shock absorber 108, the retract actuator 104, and a connecting member 1202 between the retract actuator 104 and the shock absorber 108.

[0182] In yet a further example of the retract actuator assembly 100, the retract actuator 104 further includes a rod hydraulic port 234 and a piston hydraulic port 236. The rod hydraulic port 234 is disposed near the distal end 206 of the actuator housing 202 to provide a fluid path to the rod chamber 222. The piston hydraulic port 236 is disposed near the proximal end 208 of the actuator housing 202 to provide a fluid path to the piston chamber 224.

[0183] In yet another example of the retract actuator assembly 100, the extended piston position 216 of the piston stroke 214 within the cylinder barrel 210 is associated with the fully extended state 1002 of the landing gear assembly 102 and a landing sequence of the aircraft 2400. In yet another example of the retract actuator assembly 100, the retracted piston position 218 of the piston stroke 214 within the cylinder barrel 210 is associated with the fully retracted state 802 of the landing gear assembly 102 and a takeoff sequence of the aircraft 2400. In another example of the retract actuator assembly 100, the kneeling stop position 302 of the piston stroke 214 within the cylinder barrel 210 is associated with the kneeling state 602 of the landing gear assembly 102 during ground operations of the aircraft 2400. In yet another example of the retract actuator assembly 100, the kneeling stop assembly 106 is configured to allow the piston 212 to move from the kneeling stop position 302 within the cylinder barrel 210 to the extended piston position 216 of the piston stroke 214. In yet another example of the retract actuator assembly 100, the kneeling stop assembly 106 is configured to selectively remove the kneeling stop position 302 within the cylinder barrel 210 of the piston stroke 214 to allow the piston 212 to move to the retracted piston position 218 of the piston stroke 214.

[0184] In yet another example of a retract actuator assembly 100, the kneeling stop assembly 106 includes a kneeling stop housing 1102, a kneeling stop insertion port 308, and a kneeling stop retraction port 312. The kneeling stop housing 1102 is fixed to the outer surface 220 of the actuator housing 202 of the retract actuator 104 relative to the extended piston position 216 within the cylinder barrel 210 of the retract actuator 104 and the retracted piston position 218 within the cylinder barrel 210. The kneeling stop housing 1102 includes a kneeling stop distal end 1104 closer to the distal end 206 of the actuator housing 202 and a kneeling stop proximal end 1106 closer to the proximal end 208 of the actuator housing 202. The kneeling stop housing 1102 defines a cavity 304 between the inner surface 306 of the kneeling stop housing 1102 and the outer surface 220 of the actuator housing 202. A kneeling stop insertion port 308 is provided on the kneeling stop housing 1102 to provide fluid access to a kneeling stop insertion chamber 310 formed within the cavity 304. A kneeling stop retraction port 312 is provided on the kneeling stop housing 1102 to provide fluid access to a kneeling stop retraction chamber 314 formed within the cavity 304.

[0185] In a further example, the kneeling stop insertion port 308 is configured to receive a pressurized fluid from a pressurized fluid source, and the kneeling stop assembly 106 is configured to establish the kneeling stop position 302 in response to the receipt of the pressurized fluid at the kneeling stop insertion port 308. In a further example, the pressurized fluid includes pressurized hydraulic fluid, pressurized oil, compressed gas, compressed air, or any other suitable pressurized fluid in any suitable combination. In a further example, the kneeling stop insertion port 308 is configured to allow the pressurized fluid to exit the kneeling stop assembly 106 after the pressurized fluid source no longer applies the pressurized fluid. In this example, the kneeling stop assembly 106 is configured such that the exit of the pressurized fluid via the kneeling stop insertion port 308 does not affect the current state of the kneeling stop position 302.

[0186] In another further example, the kneeling stop retract port 312 is configured to receive a pressurized fluid from a pressurized fluid source. In this example, the kneeling stop assembly 106 is configured to remove the kneeling stop position 302 in response to the receipt of the pressurized fluid at the kneeling stop retract port 312. In an even further example, the kneeling stop retract port 312 is configured to allow the pressurized fluid to exit the kneeling stop assembly 106. In this example, the kneeling stop assembly 106 is configured such that the exit of the pressurized fluid via the kneeling retract port 312 does not affect the current state of the kneeling stop position 302.

[0187] In yet a further example of the retract actuator assembly 100, the kneeling stop assembly 106 further includes at least one kneeling stop segment 1108 disposed within the cavity 304 of the kneeling stop housing 1102 at a predetermined point 1109 along the longitudinal axis 204 of the actuator housing 202. The predetermined point 1109 is associated with the kneeling stop position 302. In this example, the actuator housing 202 includes at least one kneeling stop hole 1110 extending through the actuator housing 202 to the cylinder barrel 210. The at least one kneeling stop hole 1110 is configured to receive at least a portion of the at least one kneeling stop segment 1108. The at least one kneeling stop segment 1108 is configured to be selectively inserted into the at least one kneeling stop hole 1110 and is configured to be selectively removed from the at least one kneeling stop hole 1110. In yet a further example, the at least one kneeling stop segment 1108 includes at least two kneeling stop segments 1108 radially distributed around the actuator housing 202 at the predetermined point 1109. In this example, the at least one kneeling stop hole 1110 includes at least two kneeling stop holes 1110 radially distributed around the actuator housing 202 relative to the at least two kneeling stop segments 1108.

[0188] In another further example, the at least one kneeling stop segment 1108 of the kneeling stop assembly 106 includes two kneeling stop segments, three kneeling stop segments, four kneeling stop segments, five kneeling stop segments, six kneeling stop segments, or any other suitable number of kneeling stop segments. Accordingly, the at least one kneeling stop hole 1110 of the retract actuator 104 includes two kneeling stop holes, three kneeling stop holes, four kneeling stop holes, five kneeling stop holes, six kneeling stop holes, or any other suitable number of kneeling stop holes. In yet a further example, the kneeling stop insertion port 308 is configured to receive pressurized fluid from a pressurized fluid source, and the kneeling stop assembly 106 is configured to insert the at least one kneeling stop segment 1108 into the at least one kneeling stop hole 1110 of the actuator housing 202 in response to receiving the pressurized fluid at the kneeling stop insertion port 308 to establish the kneeling stop position 302. In yet a further example, the kneeling stop retraction port 312 is configured to receive pressurized fluid from a pressurized fluid source, and the kneeling stop assembly 106 is configured to retract at least one kneeling stop segment 1108 from at least one kneeling stop hole 1110 of the actuator housing 202 in response to receipt of the pressurized fluid at the kneeling stop retraction port 312 to remove the kneeling stop position 302.

[0189] Continue to refer Figure 1-Figure 3 as well as Fig.11In one or more other examples of the retract actuator assembly 100, the kneeling stop assembly 106 further includes an upper biasing member 1112, an upper slide member 1114, a lower biasing member 1118, and a lower slide member 1120. The upper biasing member 1112 is disposed within the cavity 304 between the kneeling stop housing 1102 and the actuator housing 202 and proximate to the kneeling stop distal end 1104 of the kneeling stop housing 1102. The upper slide member 1114 is disposed within the cavity 304 between the kneeling stop housing 1102 and the actuator housing 202 and between the upper biasing member 1112 and the at least one kneeling stop segment 1108. The upper slide member 1114 includes a first portion of an upper slide outer surface 1116 that faces the inner surface 306 of the kneeling stop housing 1102. A first portion of the upper slide outer surface 1116 and a corresponding portion of the inner surface 306 of the kneeling stop housing 1102 are configured to form a kneeling stop insertion chamber 310. The upper biasing member 1112 is configured to bias the upper slide member 1114 toward the at least one kneeling stop segment 1108. The lower biasing member 1118 is disposed within the cavity 304 between the kneeling stop housing 1102 and the actuator housing 202 and proximate the kneeling stop proximal end 1106 of the kneeling stop housing 1102. The lower slide member 1120 is disposed within the cavity 304 between the kneeling stop housing 1102 and the actuator housing 202 and between the at least one kneeling stop segment 1108 and the lower biasing member 1118. The lower slide member 1120 includes a first portion of the lower slide outer surface 1122 that faces the inner surface 306 of the kneeling stop housing 1102. A first portion of the lower slide outer surface 1122 and an opposing portion of the inner surface 306 of the kneeling stop housing 1102 are configured to form a kneeling stop retraction chamber 314. The lower biasing member 1118 is configured to bias the lower slide member 1120 toward the at least one kneeling stop segment 1108.

[0190] In another example of retracting the actuator assembly 100, the upper slide member 1114 of the kneeling stop assembly 106 further includes a second portion of an upper slide outer surface 1116 in relative geometric relationship with the upper surface of the at least one kneeling stop segment 1108, and a third portion of the upper slide outer surface 1116 adjacent a corresponding portion of the outer surface 220 of the actuator housing 202. The second portion of the upper slide outer surface 1116 rises from the third portion of the upper slide outer surface 1116 to the first portion of the upper slide outer surface 1116 at a predetermined angle to facilitate retracting the at least one kneeling stop segment 1108 from the at least one kneeling stop hole 1110 of the actuator housing 202. A first portion of the upper slide outer surface 1116 and a third portion of the upper slide outer surface 1116 are configured to slide between at least one kneeling stop segment 1108 and an outer surface 220 of the actuator housing 202 in response to application of pressure at the kneeling stop retraction port 312 to prevent at least one kneeling stop segment 1108 from being inserted into at least one kneeling stop hole 1110.

[0191] In yet another example of the retracting actuator assembly 100, the lower slide member 1120 of the kneeling stop assembly 106 further includes a second portion of a lower slide outer surface 1122 in relative geometric relationship with a lower surface of the at least one kneeling stop segment 1108, and a third portion of the lower slide outer surface 1122 adjacent to a corresponding portion of the inner surface 306 of the kneeling stop housing 1102. The second portion of the lower slide outer surface 1122 descends from the first portion of the lower slide outer surface 1122 to the third portion of the lower slide outer surface 1122 at a predetermined angle to facilitate inserting the at least one kneeling stop segment 1108 into the at least one kneeling stop hole 1110 of the actuator housing 202. The first portion of the lower slide outer surface 1122 and the third portion of the lower slide outer surface 1122 are configured to slide between at least one kneeling stop segment 1108 and the inner surface 306 of the kneeling stop housing 1102 in response to the application of pressure at the kneeling stop insertion port 308 to prevent at least one kneeling stop segment 1108 from retracting from at least one kneeling stop hole 1110.

[0192] In yet another example of the retract actuator assembly 100, the kneeling stop insertion port 308 is configured to receive pressurized fluid from a pressurized fluid source and to provide the pressurized fluid to the kneeling stop insertion chamber 310. The kneeling stop assembly 106 is configured to move the upper slide member 1114 toward the upper biasing member 1112 and away from the at least one kneeling stop segment 1108 in response to the kneeling stop insertion chamber 310 receiving the pressurized fluid. The kneeling stop assembly 106 is configured to move the lower slide member 1120 toward the at least one kneeling stop segment 1108 in response to the upper slide member 1114 moving away from the at least one kneeling stop segment 1108 and the lower biasing member 1118 biasing the lower slide member 1120 toward the at least one kneeling stop segment 1108. The kneeling stop assembly 106 is configured to insert at least one kneeling stop segment 1108 into at least one kneeling stop hole 1110 of the actuator housing 202 in response to the lower sliding member 1120 moving toward at least one kneeling stop segment 1108 and pushing at least one kneeling stop segment 1108 into at least one kneeling stop hole 1110 to establish a kneeling stop position 302 within the cylinder barrel 210 of the retracting actuator 104. In a further example of the retracting actuator assembly 100, after at least one kneeling stop segment 1108 of the kneeling stop assembly 106 is inserted into at least one kneeling stop hole 1110 of the actuator housing 202, the lower biasing member 1118, the lower sliding member 1120 and the at least one kneeling stop segment 1108 are configured so that the lower sliding member 1120 moves to a locked position, which keeps the at least one kneeling stop segment 1108 inserted into the at least one kneeling stop hole 1110 with or without pressure applied to the kneeling stop insertion port 308 until pressure is applied to the kneeling stop retraction port 312.

[0193] In yet another example of the retract actuator assembly 100, the kneeling stop retract port 312 is configured to receive pressurized fluid from a pressurized fluid source and provide the pressurized fluid to the kneeling stop retract chamber 314. The kneeling stop assembly 106 is configured to move the lower slide member 1120 toward the lower biasing member 1118 and away from the at least one kneeling stop segment 1108 in response to the kneeling stop retract chamber 314 receiving the pressurized fluid. The kneeling stop assembly 106 is configured to move the upper slide member 1114 toward the at least one kneeling stop segment 1108 in response to the lower slide member 1120 moving away from the at least one kneeling stop segment 1108 and the upper biasing member 1112 biasing the upper slide member 1114 toward the at least one kneeling stop segment 1108. The kneeling stop assembly 106 is configured to retract at least one kneeling stop segment 1108 from at least one kneeling stop hole 1110 of the actuator housing 202 in response to the upper sliding member 1114 moving toward at least one kneeling stop segment 1108 and pushing at least one kneeling stop segment 1108 away from at least one kneeling stop hole 1110 to remove the kneeling stop position 302 from the cylinder barrel 210 of the retracting actuator 104. In a further example of the retracting actuator assembly 100, after at least one kneeling stop segment 1108 of the kneeling stop assembly 106 is retracted from at least one kneeling stop hole 1110 of the actuator housing 202, the upper biasing member 1112, the upper sliding member 1114 and the at least one kneeling stop segment 1108 are configured so that the upper sliding member 1114 moves to a locked position, which holds the at least one kneeling stop segment 1108 retracted from the at least one kneeling stop hole 1110 with or without pressure applied to the kneeling stop retraction port 312 until pressure is applied to the kneeling stop insertion port 308.

[0194] Overall reference Figure 1-Figure 11 , Figure 12A-12C as well as Fig.24 For example, the present disclosure relates to a landing gear assembly 102 for a landing gear assembly 102 of an aircraft 2400 . Figure 1 An example of a landing gear assembly 102 having a retract actuator assembly 100 is disclosed. Figure 2 Shown for Figure 1 FIG. 1 is a cross-sectional view of an example of a retract actuator 104 of the retract actuator assembly 100 . Figure 3 Shown for Figure 1 1 is a cross-sectional view of an example of a kneeling stop assembly 106 of a landing gear assembly 102 with a kneeling stop segment 1108 inserted into the retract actuator 104 and the retract actuator 104 in an extended position. Figure 4 Shows Figure 1 2400 is a functional diagram of landing gear assembly 102 with landing gear assembly 102 in an extended state and the weight of aircraft 2400 is on the wheels. Figure 5Shown for Figure 1 A cross-sectional view of an example of a kneeling stop assembly 106 of a landing gear assembly 102 with a kneeling stop segment 1108 inserted into the retract actuator 104 and the retract actuator 104 in a kneeling position.

[0195] Figure 6 Shows Figure 1 2400 is a functional diagram of the landing gear assembly 102, wherein the landing gear assembly 102 is in a kneeling position and the weight of the aircraft 2400 is on the wheels. Figure 7 Shown for Figure 1 1 is a cross-sectional view of an example of a kneeling stop assembly 106 of a landing gear assembly 102 with the kneeling stop segment 1108 retracted from the retract actuator 104 and the retract actuator 104 in a retracted position. Figure 8 Shows Figure 1 2400 is a functional diagram of landing gear assembly 102 with landing gear assembly 102 in a retracted state and aircraft 2400 in flight. Fig. 9 Shown for Figure 1 1 is a cross-sectional view of an example of a kneeling stop assembly 106 of a landing gear assembly 102 with the kneeling stop segment 1108 retracted from the retract actuator 104 and the retract actuator 104 in an extended position. Fig.10 Shows Figure 1 2400 is a functional diagram of landing gear assembly 102 with landing gear assembly 102 in an extended state and aircraft 2400 in flight. Fig.11 Provides and Figure 1 Examples of the retract actuator 104 of the retract actuator assembly 100 are related to Figure 3 An exploded view of an example of a kneeling stop assembly 106 .

[0196] Fig. 12A Another example of landing gear assembly 102 is disclosed, wherein landing gear assembly 102 is in an extended state and the weight of aircraft 2400 is on the wheels. Fig. 12B Shows Fig. 12A 2400 is a functional diagram of the landing gear assembly 102, wherein the landing gear assembly 102 is in a kneeling position and the weight of the aircraft 2400 is on the wheels. Fig. 12C Shows Fig. 12A 2400 is a functional diagram of landing gear assembly 102 with landing gear assembly 102 in a retracted state and aircraft 2400 in flight. Fig.24 Aircraft 2400 is shown incorporating one or more examples of landing gear assembly 102 disclosed herein.

[0197] Reference again Figure 1-Figure 11 , Figure 12A-12C as well as Fig.24In one or more examples, a landing gear assembly 102 for an aircraft 2400 includes a retract actuator 104, a kneeling stop assembly 106, a trailing arm 112, and a shock absorber 108. The retract actuator 104 includes an actuator housing 202 and a piston 212. The actuator housing 202 defines a longitudinal axis 204 extending through a distal end 206 and a proximal end 208. The actuator housing 202 includes a cylinder barrel 210 along the longitudinal axis 204. The piston 212 is disposed within the cylinder barrel 210. The piston is configured to move within the cylinder barrel 210 along the longitudinal axis 204. The cylinder barrel 210 defines a piston stroke 214 within the actuator housing 202, and the piston stroke 214 defines a limit of movement of the piston 212. The piston stroke 214 includes an extended piston position 216 associated with the distal end 206 of the actuator housing 202 and a retracted piston position 218 associated with the proximal end 208 of the actuator housing 202. The kneeling stop assembly 106 is fixed to the outer surface 220 of the actuator housing 202 relative to the extended piston position 216 within the cylinder barrel 210 and the retracted piston position 218 within the cylinder barrel 210. The kneeling stop assembly 106 is configured to selectively establish a kneeling stop position 302 within the cylinder barrel 210 to reduce the piston stroke 214 by inhibiting movement of the piston 212 toward the retracted piston position 218. The trailing arm 112 includes an arm proximal end 114 and an arm distal end 116, and the arm distal end 116 is configured to be pivotally attached to a fixed point on the aircraft 2400. The arm proximal end 114 is configured to be attached to the surface contact assembly 118. Shock absorber 108 is mechanically linked to retract actuator 104 and is configured to be pivotally attached to trailing arm 112 .

[0198] In another example of the landing gear assembly 102 , the shock absorber 108 is secured to the proximal end 208 of the actuator housing 202 such that the shock absorber 108 and the retraction actuator 104 are aligned along the longitudinal axis 204 of the actuator housing 202 to form an inline shock absorber actuator 110 .

[0199] In yet another example of the landing gear assembly 102, the piston 212 defines a rod chamber 222 in the cylinder barrel 210 associated with the distal end 206 of the actuator housing 202, and defines a piston chamber 224 in the cylinder barrel 210 associated with the proximal end 208 of the actuator housing 202. In this example, the retraction actuator 104 also includes a piston rod 226 disposed within the rod chamber 222. The piston rod 226 includes a first end 228 attached to the piston 212 and a second end 230 extending through a sealed bore 232 at the distal end 206 of the actuator housing 202.

[0200] In a further example, the second end 230 of the piston rod 226 is configured to be pivotally attached to a second fixed point on the aircraft 2400. In this example, the shock absorber 108 is fixed to the proximal end 208 of the actuator housing 202 such that the shock absorber 108 and the retraction actuator 104 are aligned along the longitudinal axis 204 of the actuator housing 202 to form an inline shock absorber actuator 110. In a further example, the mechanical linkage of the landing gear assembly 102 includes the trailing arm 112 and the inline shock absorber actuator 110.

[0201] In another further example, the second end 230 of the piston rod 226 in the retract actuator 104 is mechanically linked to the shock absorber 108, and the proximal end 208 of the actuator housing 202 is configured to be pivotally attached to a second fixed point on the aircraft 2400. In yet a further example, the mechanical linkage of the landing gear assembly 102 includes the trailing arm 112, the shock absorber 108, the retract actuator 104, and a connecting member 1202 located between the retract actuator 104 and the shock absorber 108.

[0202] In yet another example of the landing gear assembly 102, the retraction actuator 104 further includes a rod hydraulic port 234 and a piston hydraulic port 236. The rod hydraulic port 234 is disposed near the distal end 206 of the actuator housing 202 to provide a fluid passage to the rod chamber 222. The piston hydraulic port 236 is disposed near the proximal end 208 of the actuator housing 202 to provide a fluid passage to the piston chamber 224.

[0203] In yet another example of the landing gear assembly 102, the surface contacting assembly 118 includes a wheel, a skid, or any other suitable surface contacting assembly. In yet another example of the landing gear assembly 102, the extended piston position 216 of the piston stroke 214 within the cylinder barrel 210 is associated with the fully extended state 1002 of the landing gear assembly 102 and a landing sequence of the aircraft 2400. In another example of the landing gear assembly 102, the retracted piston position 218 of the piston stroke 214 within the cylinder barrel 210 is associated with the fully retracted state 802 of the landing gear assembly 102 and a takeoff sequence of the aircraft 2400. In yet another example of the landing gear assembly 102, the kneeling stop position 302 of the piston stroke 214 within the cylinder barrel 210 is associated with the kneeling stop state 602 of the landing gear assembly 102 during ground operation of the aircraft 2400. In yet another example of the landing gear assembly 102, the kneeling stop assembly 106 is configured to allow the piston 212 to move from the kneeling stop position 302 within the cylinder barrel 210 to the extended piston position 216 of the piston stroke 214. In yet another example of the landing gear assembly 102, the kneeling stop assembly 106 is configured to selectively remove the kneeling stop position 302 of the piston stroke 214 within the cylinder barrel 210 to allow the piston 212 to move to the retracted piston position 218 of the piston stroke 214.

[0204] In another example of a landing gear assembly 102, a kneeling stop assembly 106 includes a kneeling stop housing 1102, a kneeling stop insertion port 308, and a kneeling stop retraction port 312. The kneeling stop housing 1102 is fixed to an outer surface 220 of an actuator housing 202 of the retract actuator 104 relative to an extend piston position 216 within a cylinder barrel 210 of the retract actuator 104 and a retract piston position 218 within the cylinder barrel 210. The kneeling stop housing 1102 includes a kneeling stop distal end 1104 closer to a distal end 206 of the actuator housing 202 and a kneeling stop proximal end 1106 closer to a proximal end 208 of the actuator housing 202. The kneeling stop housing 1102 defines a cavity 304 between an inner surface 306 of the kneeling stop housing 1102 and an outer surface 220 of the actuator housing 202. A kneeling stop insertion port 308 is provided on the kneeling stop housing 1102 to provide fluid access to a kneeling stop insertion chamber 310 formed within the cavity 304. A kneeling stop retraction port 312 is provided on the kneeling stop housing 1102 to provide fluid access to a kneeling stop retraction chamber 314 formed within the cavity 304.

[0205] In a further example of the landing gear assembly 102, the kneeling stop assembly 106 also includes at least one kneeling stop segment 1108 disposed within the cavity 304 of the kneeling stop housing 1102 at a predetermined point 1109 along the longitudinal axis 204 of the actuator housing 202. The predetermined point 1109 is associated with the kneeling stop position 302. The actuator housing 202 includes at least one kneeling stop hole 1110 extending through the actuator housing 202 to the cylinder barrel 210. The at least one kneeling stop hole 1110 is configured to receive at least a portion of the at least one kneeling stop segment 1108. The at least one kneeling stop segment 1108 is configured to be selectively inserted into the at least one kneeling stop hole 1110 and is configured to be selectively removed from the at least one kneeling stop hole 1110. In yet a further example, the at least one kneeling stop segment 1108 includes at least two kneeling stop segments 1108 radially distributed around the actuator housing 202 at the predetermined point 1109. In this example, the at least one kneeling stop hole 1110 includes at least two kneeling stop holes 1110 radially distributed around the actuator housing 202 relative to the at least two kneeling stop segments 1108.

[0206] In another further example of the landing gear assembly 102, the kneeling stop assembly 106 further includes an upper biasing member 1112, an upper slide member 1114, a lower biasing member 1118, and a lower slide member 1120. The upper biasing member 1112 is disposed within the cavity 304 between the kneeling stop housing 1102 and the actuator housing 202 and proximate the kneeling stop distal end 1104 of the kneeling stop housing 1102. The upper slide member 1114 is disposed within the cavity 304 between the kneeling stop housing 1102 and the actuator housing 202 and between the upper biasing member 1112 and the at least one kneeling stop segment 1108. The upper slide member 1114 includes a first portion of an upper slide outer surface 1116 facing the inner surface 306 of the kneeling stop housing 1102. A first portion of the upper slide outer surface 1116 and a corresponding portion of the inner surface 306 of the kneeling stop housing 1102 are configured to form a kneeling stop insertion chamber 310. The upper biasing member 1112 is configured to bias the upper slide member 1114 toward the at least one kneeling stop segment 1108. The lower biasing member 1118 is disposed within the cavity 304 between the kneeling stop housing 1102 and the actuator housing 202 and proximate the kneeling stop proximal end 1106 of the kneeling stop housing 1102. The lower slide member 1120 is disposed within the cavity 304 between the kneeling stop housing 1102 and the actuator housing 202 and between the at least one kneeling stop segment 1108 and the lower biasing member 1118. The lower slide member 1120 includes a first portion of the lower slide outer surface 1122 that faces the inner surface 306 of the kneeling stop housing 1102. A first portion of the lower slide outer surface 1122 and an opposing portion of the inner surface 306 of the kneeling stop housing 1102 are configured to form a kneeling stop retraction chamber 314. The lower biasing member 1118 is configured to bias the lower slide member 1120 toward the at least one kneeling stop segment 1108.

[0207] Overall reference Figure 1-Figure 11 , Figure 13-Figure 22 as well as Fig.24 For example, the present disclosure relates to methods 1300 , 1400 , 1500 , 1600 , 1700 , 1800 , 1900 , 2000 , 2100 , 2200 of kneeling a landing gear assembly 102 of an aircraft 2400 . Figure 1 An example of an example retraction actuator assembly 100 for use with a landing gear assembly 102 is disclosed. Figure 2 Shown for Figure 1 FIG. 1 is a cross-sectional view of an example of a retract actuator 104 of the retract actuator assembly 100 . Figure 3 Shown for Figure 1 1 is a cross-sectional view of an example of a kneeling stop assembly 106 of a retract actuator assembly 100 with a kneeling stop segment 1108 inserted into the retract actuator 104 and the retract actuator 104 in an extended position. Figure 4 Shows Figure 1 2400 is a functional diagram of landing gear assembly 102 with landing gear assembly 102 in an extended state and the weight of aircraft 2400 is on the wheels. Figure 5 Shown for Figure 1 1 is a cross-sectional view of an example of a kneeling stop assembly 106 of a retract actuator assembly 100 with a kneeling stop segment 1108 inserted into the retract actuator 104 and the retract actuator 104 in a kneeling position.

[0208] Figure 6 Shows Figure 1 2400 is a functional diagram of the landing gear assembly 102, wherein the landing gear assembly 102 is in a kneeling position and the weight of the aircraft 2400 is on the wheels. Figure 7 Shown for Figure 1 1 is a cross-sectional view of an example of a kneeling stop assembly 106 of a retract actuator assembly 100 with the kneeling stop segment 1108 retracted from the retract actuator 104 and the retract actuator 104 in a retracted position. Figure 8 Shows Figure 1 2400 is a functional diagram of landing gear assembly 102 with landing gear assembly 102 in a retracted state and aircraft 2400 in flight. Fig. 9 Shown for Figure 1 1 is a cross-sectional view of an example of a kneeling stop assembly 106 of a retract actuator assembly 100 with the kneeling stop segment 1108 retracted from the retract actuator 104 and the retract actuator 104 in an extended position. Fig.10 Shows Figure 1 2400 is a functional diagram of landing gear assembly 102 with landing gear assembly 102 in an extended state and aircraft 2400 in flight. Fig.11 Provides and Figure 1 Examples of the retract actuator 104 of the retract actuator assembly 100 are related to Figure 3 An exploded view of an example of a kneeling stop assembly 106 .

[0209] Fig.13 An example of a method 1300 of kneeling a landing gear assembly 102 of an aircraft 2400 is disclosed. Fig.14 Combination Fig.13 An example of a method 1400 of kneeling a landing gear assembly 102 of an aircraft 2400 is disclosed. Fig.15 Combination Fig.13 An example of a method 1500 of kneeling a landing gear assembly 102 of an aircraft 2400 is disclosed. Fig.16 Combination Fig.13 An example of a method 1600 of kneeling a landing gear assembly 102 of an aircraft 2400 is disclosed. Fig.17 Combination Fig.13 and Fig.16 An example of a method 1700 of kneeling a landing gear assembly 102 of an aircraft 2400 is disclosed. Fig.18 Combination Fig.13 An example of a method 1800 of kneeling a landing gear assembly 102 of an aircraft 2400 is disclosed. Fig.19 Combination Fig.13 and Fig.18 An example of a method 1900 of kneeling a landing gear assembly 102 of an aircraft 2400 is disclosed. Fig. 20 Combination Fig.13 and Fig.18 An example of a method 2000 of kneeling a landing gear assembly 102 of an aircraft 2400 is disclosed. Fig.21 Combination Fig.13 and Fig.18 An example of a method 2100 of kneeling a landing gear assembly 102 of an aircraft 2400 is disclosed. Fig. 22 Combination Fig.13 , Fig.18 and Fig.21 An example of a method 2200 of kneeling a landing gear assembly 102 of an aircraft 2400 is disclosed. Fig.24 An aircraft 2400 is shown incorporating one or more examples of the retraction actuator assembly 100 and landing gear assembly 102 disclosed herein.

[0210] Reference again Figure 1-Figure 3 , Figure 6 , Fig.10 , Fig.13 and Fig.24 In one or more examples, the method 1300 of kneeling the landing gear assembly 102 of the aircraft 2400 (see Fig.13 ) includes performing 1302 ground operations of the aircraft 2400 with the landing gear assembly 102 in the fully extended state 1002 and the retraction actuator 104 of the landing gear assembly 102 in the extended piston position 216. At 1304, the kneeling feature of the landing gear assembly 102 is enabled to establish a kneeling stop position 302 in the retraction actuator 104, which reduces the piston stroke 214 of the retraction actuator 104 by inhibiting movement of the piston 212 in the retraction actuator 104 beyond the kneeling stop position 302 toward the retraction piston position 218. At 1306, the landing gear assembly 102 is moved from the fully extended state 1002 to the kneeling state 602 by moving the retraction actuator 104 from the extended piston position 216 to the kneeling stop position 302.

[0211] In another example of the method 1300, the extended piston position 216 of the piston stroke 214 within the cylinder barrel 210 of the retract actuator 104 is associated with the fully extended state 1002 of the landing gear assembly 102 and a landing sequence of the aircraft 2400. In yet another example of the method 1300, the retracted piston position 218 of the piston stroke 214 within the cylinder barrel 210 of the retract actuator 104 is associated with the fully retracted state 802 of the landing gear assembly 102 and a takeoff sequence of the aircraft 2400. In yet another example of the method 1300, the kneeling stop position 302 of the piston stroke 214 within the cylinder barrel 210 of the retract actuator 104 is associated with the kneeling state 602 of the landing gear assembly 102 during ground operations of the aircraft 2400. In yet another example, the method 1300 further includes moving 1308 the landing gear assembly 102 from the kneeled state 602 to the fully extended state 1002 by moving the retract actuator 104 from the kneeled stop position 302 to the extend piston position 216 while the kneeling feature of the landing gear assembly 102 is still enabled.

[0212] Reference again Figure 1-Figure 3 , Fig.13 , Fig.14 and Fig.24 In one or more examples, a method 1400 for kneeling a landing gear assembly 102 of an aircraft 2400 (see Fig.14 )include Fig.13 The method 1300 continues from 1304 to 1402, wherein the kneeling stop position 302 is established in the retract actuator 104 in response to receiving a pressurized fluid from a pressurized fluid source at a kneeling stop insertion port 308 of a kneeling stop assembly 106 fixed to an outer surface 220 of the retract actuator 104. The method 1400 continues from 1402 to 1306 (see Fig.13 In another example, the method further includes allowing 1404 the pressurized fluid to exit the kneeling stop assembly 106 via the kneeling stop insertion port 308 without affecting the current state of the kneeling stop position 302 after the pressurized fluid source no longer applies the pressurized fluid.

[0213] Reference again Figure 1-Figure 3 , Fig.11 , Fig.13 , Fig.15 and Fig.24 In one or more examples, a method 1500 for kneeling a landing gear assembly 102 of an aircraft 2400 (see Fig.15 )include Fig.13The method 1500 continues from 1304 to 1502, wherein in response to receiving a pressurized fluid from a pressurized fluid source at a kneeling stop insertion port 308 of the kneeling stop assembly 106, a kneeling stop position 302 is established in the retract actuator 104 by inserting at least one kneeling stop segment 1108 of the kneeling stop assembly 106 fixed to the outer surface 220 of the retract actuator 104 into at least one kneeling stop hole 1110 extending through the outer surface 220 to the cylinder barrel 210 of the retract actuator 104. The method 1500 continues from 1502 to 1306 (see Fig.13 ).

[0214] Reference again Figure 1-Figure 3 , Fig.11 , Fig.13 , Fig.16 and Fig.24 In one or more examples, a method 1600 for kneeling a landing gear assembly 102 of an aircraft 2400 (see Fig.16 )include Fig.13The method 1600 continues from 1304 to 1602, wherein a kneeling stop position 302 is established in the retract actuator 104. At 1604, establishing 1602 includes moving an upper slide member 1114 of the kneeling stop assembly 106 secured to an outer surface 220 of the retract actuator 104 toward an upper biasing member 1112 of the kneeling stop assembly 106 and away from at least one kneeling stop segment 1108 of the kneeling stop assembly 106 in response to receiving a pressurized fluid from a pressurized fluid source at a kneeling stop insertion chamber 310 of the kneeling stop assembly 106 via a kneeling stop insertion port 308 of the kneeling stop assembly 106. After 1604, after the upper slide member 1114 moves toward the upper biasing member 1112, the at least one kneeling stop segment 1108 is no longer locked and is free to move laterally between the inner surface 306 of the kneeling stop housing 1102 and the outer surface 220 of the actuator housing 202. At 1606, establishing 1602 also includes moving the lower slide member 1120 of the kneeling stop assembly 106 toward the at least one kneeling stop segment 1108 in response to the upper slide member 1114 moving away from the at least one kneeling stop segment 1108, the at least one kneeling stop segment 1108 being free to move laterally and the lower biasing member 1118 biasing the lower slide member 1120 toward the at least one kneeling stop segment 1108. At 1608, establishing 1602 further includes inserting the at least one kneeling stop segment 1108 into the at least one kneeling stop hole 1110 extending through the outer surface 220 to the cylinder barrel 210 of the retract actuator 104 in response to the lower slide member 1120 moving toward the at least one kneeling stop segment 1108 and the relative tapered surface of the lower slide member 1120 pushing the at least one kneeling stop segment 1108 into the at least one kneeling stop hole 1110 to establish the kneeling stop position 302 within the cylinder barrel 210 of the retract actuator 104. The method 1600 continues from 1602 to 1306 (see Fig.13 ).

[0215] Reference again Figure 1-Figure 3 , Fig.11 , Fig.13 , Fig.16 , Fig.17 and Fig.24 In one or more examples, the method 1700 of kneeling the landing gear assembly 102 of the aircraft 2400 (see Fig.17 )include Fig.13 and Fig.16Method 1700 continues from 1608 to 1702, wherein the kneeling stop position 302 in the retracting actuator 104 is locked after the at least one kneeling stop segment 1108 of the kneeling stop assembly 106 is inserted into the at least one kneeling stop hole 1110 of the actuator housing 202. At 1704, the at least one kneeling stop segment 1108 is maintained inserted into the at least one kneeling stop hole 1110 with or without pressure applied to the kneeling stop insertion port 308 until pressure is applied to the kneeling stop retraction port 312 of the kneeling stop assembly 106.

[0216] Reference again Figure 1-Figure 3 , Fig.10 , Fig.13 , Fig.18 and Fig.24 In one or more examples, the method 1800 of kneeling the landing gear assembly 102 of the aircraft 2400 (see Fig.18 )include Fig.13 The method 1800 continues from 1306 to 1802, where the kneeling feature of the landing gear assembly 102 is deactivated to remove the kneeling stop position 302 from the retract actuator 104, thereby allowing the piston 212 to move to the retract piston position 218 of the piston stroke 214. At 1804, a takeoff sequence of the aircraft 2400 begins, where the landing gear assembly 102 is in the fully extended state 1002 and the retract actuator 104 of the landing gear assembly 102 is in the extended piston position 216. At 1806, the takeoff sequence is completed and a flight operation of the aircraft 2400 is performed, where the landing gear assembly 102 is in the fully retracted state 802 and the retract actuator 104 is in the retract piston position 218.

[0217] Reference again Figure 1-Figure 3 , Fig.13 , Fig.18 , Fig.19 and Fig.24 In one or more examples, the method 1900 of kneeling the landing gear assembly 102 of the aircraft 2400 (see Fig.19 )include Fig.13 and Fig.18 Method 1300, 1800. Method 1900 continues from 1802 to 1902, wherein in response to receiving a pressurized fluid from a pressurized fluid source at a kneeling stop retraction port 312 of a kneeling stop assembly 106 fixed to an outer surface 220 of the retract actuator 104, the kneeling stop position 302 is removed from the retract actuator 104. Method 1900 continues from 1902 to 1804 (see Fig.18In another example, the method 1900 further includes allowing 1904 the pressurized fluid to exit the kneeling stop assembly 106 via the kneeling stop retract port 312 without affecting the current state of the kneeling stop position 302 after the pressurized fluid source is no longer applying the pressurized fluid.

[0218] Reference again Figure 1-Figure 3 , Fig.11 , Fig.13 , Fig.18 , Fig. 20 and Fig.24 In one or more examples, the method 2000 of kneeling the landing gear assembly 102 of the aircraft 2400 (see Fig. 20 )include Fig.13 and Fig.18 Method 2000 continues from 1802 to 2002, wherein in response to receiving a pressurized fluid from a pressurized fluid source at a kneeling stop retraction port 312 of the kneeling stop assembly 106, the kneeling stop position 302 is removed from the retract actuator 104 by retracting at least one kneeling stop segment 1108 of the kneeling stop assembly 106 fixed to the outer surface 220 of the retract actuator 104 from at least one kneeling stop hole 1110 extending through the outer surface 220 to the cylinder barrel 210 of the retract actuator 104. Method 2000 continues from 2002 to 1804 (see Fig.18 ).

[0219] Reference again Figure 1-Figure 3 , Fig.11 , Fig.13 , Fig.18 , Fig.21 and Fig.24 In one or more examples, the method 2100 of kneeling the landing gear assembly 102 of the aircraft 2400 (see Fig.21 )include Fig.13 and Fig.18The method 2100 continues from 1802 to 2102, wherein the kneeling stop position 302 is removed from the retract actuator 104. At 2104, the removal 2102 includes moving a lower slide member 1120 of the kneeling stop assembly 106 secured to an outer surface 220 of the retract actuator 104 toward a lower biasing member 1118 of the kneeling stop assembly 106 and away from at least one kneeling stop segment 1108 of the kneeling stop assembly 106 in response to receiving a pressurized fluid from a pressurized fluid source at a kneeling stop retract chamber 314 of the kneeling stop assembly 106 via a kneeling stop retract port 312 of the kneeling stop assembly 106. After the lower slide member 1120 moves toward the lower biasing member 1118, the at least one kneeling stop segment 1108 is no longer locked and is free to move laterally between the inner surface 306 of the kneeling stop housing 1102 and the outer surface 220 of the actuator housing 202. At 2106, the removal 2102 also includes moving the upper slide member 1114 of the kneeling stop assembly 106 toward the at least one kneeling stop segment 1108 in response to the lower slide member 1120 moving away from the at least one kneeling stop segment 1108, the at least one kneeling stop segment 1108 being free to move laterally and the upper biasing member 1112 biasing the upper slide member 1114 toward the at least one kneeling stop segment 1108. At 2108, removal 2102 also includes retracting at least one kneeling stop segment 1108 from at least one kneeling stop hole 1110 extending through the outer surface 220 to the cylinder barrel 210 of the retract actuator 104 in response to the upper sliding member 1114 moving toward the at least one kneeling stop segment 1108 and the relative conical surface of the upper sliding member 1114 pushing the at least one kneeling stop segment 1108 away from the at least one kneeling stop hole 1110 to remove the kneeling stop position 302 from the cylinder barrel 210 of the retract actuator 104.

[0220] Reference again Figure 1-Figure 3 , Fig.11 , Fig.13 , Fig.18 , Fig.21 , Fig. 22 and Fig.24 In one or more examples, the method 2200 of kneeling the landing gear assembly 102 of the aircraft 2400 (see Fig. 22 )include Fig.13 , Fig.18 and Fig.21The method 2200 continues from 2108 to 2202, wherein the kneeling stop position 302 in the retracting actuator 104 is locked out after the at least one kneeling stop segment 1108 of the kneeling stop assembly 106 is retracted from the at least one kneeling stop hole 1110 of the actuator housing 202. At 2204, the at least one kneeling stop segment 1108 is maintained retracted from the at least one kneeling stop hole 1110 with or without pressure applied to the kneeling stop retraction port 312 until pressure is applied to the kneeling stop insertion port 308 of the kneeling stop assembly 106.

[0221] The examples of the retracting actuator assembly 100, the landing gear assembly 102, and the methods 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2100, 2200 of kneeling the landing gear assembly 102 of the aircraft 2400 may be related to or used in the context of aircraft manufacturing. Although an aircraft example is described, the examples and principles disclosed herein may be applicable to other products in the aerospace industry as well as other industries such as the automotive industry, the aerospace industry, the construction industry, and other design and manufacturing industries. Therefore, in addition to aircraft, the examples and principles disclosed herein may also be applicable to the use of kneeling in the manufacture and / or operation of various types of vehicles and in the construction of various types of buildings.

[0222] The above specific embodiments refer to the accompanying drawings, which illustrate the specific examples described in the present disclosure. Other examples with different structures and operations do not depart from the scope of the present disclosure. In different drawings, the same reference numerals may refer to the same features, elements or parts. Throughout the present disclosure, any one of a plurality of projects may be referred to as a project individually, and a plurality of projects may be collectively referred to as a project and may be referred to by the same reference numerals. In addition, as used herein, features, elements, parts or steps beginning with the word "one" or "a kind of" should also be understood to not exclude a plurality of features, elements, parts or steps, unless such exclusion is explicitly described.

[0223] The above provides illustrative, non-exhaustive examples according to the subject matter of the present disclosure, which examples may be, but not necessarily, claimed. Reference to "example" herein means that one or more features, structures, elements, parts, characteristics and / or operating steps described in conjunction with the example are included in at least one aspect, embodiment and / or implementation of the subject matter of the present disclosure. Therefore, the phrases "an example", "another example", "one or more examples" and similar terms throughout the present disclosure may, but do not necessarily refer to the same example. In addition, the subject matter representing any one example may, but does not necessarily include the subject matter representing any other example. In addition, the subject matter representing any one example may, but does not necessarily combine with the subject matter representing any other example.

[0224] As used herein, a system, device, apparatus, structure, article, element, component or hardware that is "configured to" perform a specified function is indeed capable of performing the specified function without any changes, rather than having only the potential to perform the specified function after further modification. In other words, a system, device, apparatus, structure, article, element, component or hardware that is "configured to" perform a specified function is specifically selected, created, implemented, utilized, programmed and / or designed for the purpose of performing the specified function. As used herein, "configured to" represents an existing characteristic of a system, device, structure, article, element, component or hardware that enables the system, device, structure, article, element, component or hardware to perform the specified function without further modification. For the purposes of this disclosure, a system, device, apparatus, structure, article, element, component or hardware that is described as "configured to" perform a specific function may be additionally or alternatively described as "suitable for" and / or "operable to" perform the function.

[0225] Unless otherwise indicated, the terms "first", "second", "third", etc. are used herein merely as labels and are not intended to impose order, positioning, or hierarchy requirements on the items to which these terms refer. In addition, reference to, for example, a "second" item does not require or exclude the presence of, for example, a "first" or lower numbered item and / or, for example, a "third" or higher numbered item.

[0226] As used herein, when used with a list of items, the phrase "at least one of..." means that different combinations of one or more of the listed items may be used, and only one of each item in the list may be required. For example, "at least one of item A, item B, and item C" may include, but is not limited to, item A or item A and item B. This example may also include item A, item B, and item C or item B and item C. In other examples, "at least one of..." may be, for example, but not limited to, two of item A, one of item B, and ten of item C; four of item B and seven of item C; and other suitable combinations. As used herein, the term "and / or" and the " / " symbol include any and all combinations of one or more of the associated listed items.

[0227] As used herein, the terms "coupled," "coupling," and similar terms refer to two or more elements that are linked, linked, fastened, attached, connected, communicated, or otherwise associated (e.g., mechanically, electrically, fluidically, optically, electromagnetically) with one another. In various examples, these elements may be associated directly or indirectly. As an example, element A may be directly associated with element B. As another example, element A may be indirectly associated with element B, such as via another element C. It will be understood that not all associations between the various disclosed elements are necessarily represented. Therefore, couplings may also exist in addition to those shown in the figures.

[0228] As used herein, the term "approximately" refers to or indicates conditions that are close to, but not exactly, the stated conditions, which still perform the desired function or achieve the desired result. As an example, the term "approximately" refers to conditions that are within an acceptable predetermined tolerance or accuracy, such as conditions within 10% of the stated conditions. However, the term "approximately" does not exclude conditions that are exactly the stated conditions. As used herein, the term "substantially" refers to conditions that are essentially the stated conditions that perform the desired function or achieve the desired result.

[0229] In the above mentioned Figure 1-Figure 11 , Figure 12A-12C as well as Fig.24 , may represent functional elements, features or components thereof, and does not necessarily imply any specific structure. Therefore, modifications, additions and / or omissions may be made to the structures shown. In addition, those skilled in the art will appreciate that the above-mentioned Figure 1-Figure 11 , Figure 12A-12C as well as Fig.24 Not all elements, features, and / or components described and illustrated herein need to be included in every example, and not all elements, features, and / or components described herein need to be depicted in every illustrative example. Figure 1-Figure 11 , Figure 12A-12C as well as Fig.24 Some of the elements, features and / or components described and shown in the drawings may be combined in various ways without necessarily including Figure 1-Figure 11 , Figure 12A-12C as well as Fig.24 , other figures and / or the accompanying disclosure, even if such a combination is not explicitly stated herein. Similarly, additional features not limited to the examples presented may be combined with some or all of the features shown and described herein. Figure 1-Figure 11 , Figure 12A-12C as well as Fig.24The schematic illustration of the examples shown in is not intended to imply structural limitations to the illustrative examples. Specifically, although an illustrative structure is indicated, it should be understood that the structure may be modified when appropriate. Therefore, modifications, additions and / or omissions may be made to the illustrated structure. In addition, Figure 1-Figure 11 , Figure 12A-12C as well as Fig.24 In each of the , elements, features and / or components that achieve similar or at least substantially similar purposes are labeled with like numerals, and such elements, features and / or components may not be referred to herein. Figure 1-Figure 11 , Figure 12A-12C as well as Fig.24 Each of these is discussed in detail. Similarly, Figure 1-Figure 11 , Figure 12A-12C as well as Fig.24 Not all elements, features, and / or components may be labeled in each of the embodiments, but the reference numerals associated therewith may be used herein for consistency.

[0230] In Figure 12 mentioned above, Fig.23 In the present disclosure, boxes may represent operations, steps and / or parts thereof, and the lines connecting the boxes do not imply any particular order or dependency between the operations or parts thereof. It will be understood that not all dependencies between the various disclosed operations must be represented. Fig.23 And the accompanying disclosure describing the operation of the disclosed method set forth herein should not be interpreted as necessarily determining the order in which the operations are to be performed. Specifically, although an illustrative order is indicated, it should be understood that the order of operations can be modified when appropriate. Therefore, the operations shown can be modified, added and / or omitted, and some operations can be performed in different orders or performed simultaneously. In addition, those skilled in the art will understand that not all described operations need to be performed.

[0231] In addition, references throughout this specification to similar features, advantages, or terms used herein do not imply that all features and advantages that can be realized with the examples disclosed herein should be or are present in any single example. Rather, terms referring to features and advantages are understood to mean that a specific feature, advantage, or characteristic described in conjunction with an example is included in at least one example. Therefore, discussions of features, advantages, and similar terms used throughout this disclosure may, but do not necessarily, refer to the same example.

[0232] Examples of the subject matter disclosed herein can be found at Fig.15 Aircraft manufacturing and service method 2300 is shown and Fig.162300 is described in the context of the aircraft 2400 shown. In one or more examples, the disclosed methods and systems for associating test data of a tested part with a final project coordinate system can be used in aircraft manufacturing. During pre-production, the service method 2300 may include specification and design of the aircraft 2400 (box 2302) and material procurement (box 2304). During production, component and subassembly manufacturing (box 2306) and system integration (box 2308) of the aircraft 2400 may be performed. Thereafter, the aircraft 2400 may be certified and delivered (box 2310) to be placed in service (box 2312). While in service, the aircraft 2400 may be scheduled for routine maintenance and servicing (box 2314). Routine maintenance and servicing may include modification, reconfiguration, refurbishment, etc. of one or more systems of the aircraft 2400.

[0233] Each process pair of service method 2300 can be performed or implemented by a system integrator, a third party, and / or an operator (e.g., a customer). For the purposes of this specification, a system integrator may include, but is not limited to, any number of aircraft manufacturers and main system subcontractors; a third party may include, but is not limited to, any number of dealers, subcontractors, and suppliers; and an operator may be an airline, a leasing company, a military entity, a service organization, and the like.

[0234] like Fig.16 As shown, an aircraft 2400 produced by service method 2300 may include a fuselage 2402 having a plurality of high-level systems 2404 and an interior 2406. Examples of high-level systems 2404 include one or more propulsion systems 2408, electrical systems 2410, hydraulic systems 2412, and environmental systems 2414. Any number of other systems may be included. Although an example of aerospace is shown, the principles disclosed herein may be applicable to other industries, such as the automotive industry. Therefore, in addition to aircraft 2400, the principles disclosed herein may be applicable to other vehicles, such as land vehicles, marine vehicles, space vehicles, etc.

[0235] The disclosed methods and systems for associating test data of a tested part with a final project coordinate system may be employed during any one or more stages of the manufacturing and service method 2300. For example, components or subassemblies corresponding to component and subassembly manufacturing (block 2306) may be fabricated or manufactured in a manner similar to components or subassemblies produced when the aircraft 2400 is in service (block 2312). In addition, one or more examples of the system(s), method(s), or a combination thereof may also be utilized during the production stage (blocks 2306 and 2308), for example, resulting in significantly faster assembly or reduced cost of the aircraft 2400. Similarly, for example, but not limited to, one or more examples of system or method implementations, or a combination thereof, may be utilized when the aircraft 2400 is in service (block 2312) and / or during maintenance and service (block 2314).

[0236] The features, advantages and characteristics of one example described may be combined in one or more other examples in any suitable manner. Those skilled in the relevant art will recognize that the examples described herein may be practiced in the absence of one or more specific features or advantages of a particular example. In other cases, additional features and advantages that may not be present in all examples may be recognized in certain examples. In addition, although various examples of retracting the actuator assembly 100, the landing gear assembly 102, and the method 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2100, 2200 of kneeling the landing gear assembly 102 of the aircraft 2400 have been shown and described, modifications may be conceived by those skilled in the art after reading the specification. The present application includes these modifications and is limited only by the scope of the claims.

Claims

1. A retraction actuator assembly (100) for a landing gear assembly (102) of an aircraft (2400), the retraction actuator assembly (100) comprising: A retracting actuator (104) comprising: an actuator housing (202) defining a longitudinal axis (204) extending through a distal end (206) and a proximal end (208), The actuator housing (202) includes a cylinder barrel (210) along the longitudinal axis (204); and A piston (212) disposed within the cylinder barrel (210) and configured to move along the longitudinal axis (204) within the cylinder barrel (210), the cylinder barrel (210) defining a cylinder in the actuator housing (202) a piston stroke (214) that limits movement of the piston (212), the piston stroke (214) including an extended piston position (216) associated with the distal end (206) of the actuator housing (202) and a retracted piston position (218) associated with the proximal end (208) of the actuator housing (202); and A kneeling stop assembly (106) is fixed to an outer surface (220) of the actuator housing (202) relative to the extended piston position (216) within the cylinder barrel (210) and the retracted piston position (218) within the cylinder barrel (210), the kneeling stop assembly (106) being configured to selectively establish a kneeling stop position (302) within the cylinder barrel (210) to reduce the piston stroke (214) by inhibiting movement of the piston (212) toward the retracted piston position (218).

2. The retract actuator assembly of claim 1 , further comprising: A shock absorber (108) is fixed to the proximal end (208) of the actuator housing (202) such that the shock absorber (108) and the retract actuator (104) are aligned along the longitudinal axis (204) of the actuator housing (202) to form an in-line shock absorber actuator (110), the shock absorber (108) being configured to be pivotally attached to a trailing arm (112) of the landing gear assembly (102).

3. The retract actuator assembly of claim 1, wherein the piston (212) defines a rod chamber (222) in the cylinder barrel (210) associated with the distal end (206) of the actuator housing (202) and defines a piston chamber (224) in the cylinder barrel (210) associated with the proximal end (208) of the actuator housing (202), the retract actuator (104) further comprising: A piston rod (226) is disposed within the rod chamber (222) and includes a first end (228) attached to the piston (212) and a second end (230) extending through a sealed bore (232) at the distal end (206) of the actuator housing (202).

4. The retract actuator assembly of claim 3, wherein the second end (230) of the piston rod (226) is configured to be pivotally attached to a fixed point on the aircraft (2400), the retract actuator assembly (100) further comprising: A shock absorber (108) is secured to the proximal end (208) of the actuator housing (202) such that the shock absorber (108) and the retract actuator (104) are aligned along the longitudinal axis (204) of the actuator housing (202) to form an in-line shock absorber actuator (110), the shock absorber (108) being configured to be pivotally attached to a trailing arm (112) of the landing gear assembly (102).

5. The retraction actuator assembly of claim 4, wherein the mechanical linkage of the landing gear assembly (102) comprises a trailing arm (112) of the landing gear assembly (102) and the inline shock absorber actuator (110).

6. The retract actuator assembly of claim 3, wherein the proximal end (208) of the actuator housing (202) is configured to be pivotally attached to a fixed point on the aircraft (2400), the retract actuator assembly (100) further comprising: A shock absorber (108) is mechanically linked to the second end (230) of the piston rod (226), the shock absorber (108) being configured to be pivotally attached to a trailing arm (112) of the landing gear assembly (102).

7. The retraction actuator assembly of claim 6, wherein the mechanical linkage of the landing gear assembly (102) comprises a trailing arm (112) of the landing gear assembly (102), the shock absorber (108), the retraction actuator (104), and a connecting member (1202) between the retraction actuator (104) and the shock absorber (108).

8. The retract actuator assembly of claim 3, the retract actuator (104) further comprising: a rod hydraulic port (234) disposed near the distal end (206) of the actuator housing (202) to provide fluid access to the rod chamber (222); and A piston hydraulic port (236) is disposed near the proximal end (208) of the actuator housing (202) to provide fluid access to the piston chamber (224).

9. The retract actuator assembly of claim 1, wherein the piston stroke (214) and the extend piston position (216) within the cylinder barrel (210) are related to a fully extended state (1002) of the landing gear assembly (102) and a landing sequence of the aircraft (2400).

10. The retract actuator assembly of claim 1, wherein the retract piston position (218) within the cylinder barrel (210) of the piston stroke (214) is associated with a fully retracted state (802) of the landing gear assembly (102) and a takeoff sequence of the aircraft (2400).

Images