Abstract:
An auxiliary actuator (49) comprises a two stage telescopic hydraulic unit comprising first (59, 63) and second (56, 50) stage piston and cylinder actuators operating coaxially within an outer casing (50). A respective actuator is connected to a respective one of the strut (1) and bogie beam (4). The second stage actuator (56, 60) serves to control the tilt position of the bogie beam (4) relative to the strut (1). The second stage actuator (56. 60), when in the retracted position with the first stage actuator (59, 63) in the extended position, limits the length ol the auxiliary actuator (9) between its connections (62,67) to the strut (1) and bogie beam (4), so as to assume a predetermined intermediate length in which the bogie beam (4) is restrained to tilt about the auxiliary pivot (14) and thereby lengthens the landing gear during take-off.
Abstract:
A semi-levered landing gear for an aircraft includes a main shock absorber strut, a bogie beam and an auxiliary actuator mechanism. The bogie beam extends fore and aft of an airframe of the aircraft with forward and aft axles for respective forward and aft wheels, and a main pivot between the forward and aft axle pivotally connected to the lower portion of the main shock absorber strut. The auxiliary actuator mechanism includes a spring unit pivotally connected at a lower end to an auxiliary pivot on the bogie forward of the main pivot, and at an upper end to an anchor point offset from the pivot connection of the upper portion to the aircraft fuselage. During stowing the strut and spring unit pivot together about different pivot points, causing a relative longitudinal movement between the main pivot and auxiliary pivot that further tilts the bogie beam to a stowing position.
Abstract:
A semi-levered landing gear for an aircraft comprises a main shock absorber strut (1) connected to the airframe; a bogie beam (4) extending fore and aft of the airframe with forward and aft wheels (J, T) and a main pivot connection (5) to the strut (1) between the forward and aft wheels (7, T) and an auxiliary actuator (49) connected between the strut (1) and the front of the bogie beam (4) at an auxiliary pivot (14). The auxiliary actuator (49) comprises a two stage telescopic hydraulic unit comprising a first stage piston and cylinder actuator (59, 63) and a second stage piston and cylinder actuator (56, 50) operating coaxially within an outer casing (50). A respective piston rod (65, 60) each extends from each end of the casing (50) and is connected to a respective one of said (strut 1) and bogie beam (4). The first stage actuator (59, 63) is operable to an extended position, and the second stage actuator (56, 60) is operable between a retracted position (FIG. 11) and an extended position (FIG. 12) defined by respective end stops (75, 77) within the outer casing (50) and serves to control the tilt position of the bogie beam (4) relative to the strut (1). The second stage actuator (56, 60), when in the retracted position with the first stage actuator (59, 63) in the extended position, limits the length of the auxiliary actuator (9) between its connections (62, 67) to the strut (1) and bogie beam (4), so as to assume a predetermined intermediate length in which the bogie beam (4) is restrained to tilt about the auxiliary pivot (14) and thereby lengthens the landing gear during take-off. The second stage actuator (56, 60), when in the extended position with the first stage actuator (59, 63) in the extended position, allows the length of the auxiliary actuator (49) to assume a predetermined maximum length in which the bogie beam (4) is tilted about the main pivot (5) to a stowing position for stowing the landing gear in the aircraft.
Abstract:
An auxiliary actuator mechanism includes a lever, a spring unit and a control linkage. The lever is pivotally connected to the upper portion of a main shock absorber strut, and pivotable between an upper position for take-off, and a lower position. The spring unit is pivotally connected at an upper end to the lever and at a lower end to the bogie at an auxiliary pivot forward of the main pivot. The control linkage is connected between the lever and the upper portion of the main shock absorber strut to define the upper predetermined position of the lever. The control linkage is connectable to an anchor point that moves relative to the upper portion of the main shock absorber strut during stowing, and is operated by initial stowing movement of the stowing mechanism to lower the lever from the upper position to a stowing position.
Abstract:
A system and method for verifying the integrity of control information and informational data. One embodiment of the present invention verifies the integrity of control information received from a host computer, and verifies the integrity of this information as it is transmitted throughout the present invention. Another embodiment of the present invention contemplates verifying the integrity of informational data sent from a host computer, verifying the integrity of informational data as it is transmitted throughout the present invention, generating a CRC based upon the informational data and control information, and transmitting the informational data, control information and corresponding CRC to a storage device.
Abstract:
An auxiliary mechanism includes a lever unit, a spring unit and a positioning unit. One of the units pivotally connects to the upper portion of a main shock absorber strut so as to pivot between a predetermined lower position for take-off and landing and an upper position. Another unit pivotally connects at an upper end to the upper portion of the main shock absorber strut and pivotally connects at a lower end to the first unit. A third unit pivotally connects at a lower end to the bogie beam at an auxiliary pivot and connects at an upper end to the lever. The positioning unit assumes either a contracted state or extended state for taxiing, take-off and landing, and assumes the other state for stowing the landing gear after take-off. The spring unit provides spring resistance to pivotal movements of the bogie beam about the main pivot during taxiing.