(2)
The upper link connects to the shock strut outer cylinder, the lower link connects to the inner cylinder, and the two links are connected together to form a hinged joint.
D.
Truck Assembly (Fig. 1)
______________
(1)
The truck assembly distributes airplane loads from the shock strut to the wheels and tires. The assembly consists of a truck beam, axles, brake rods, and a protective shield.
(2)
The truck beam is the primary supporting member of the truck assembly. It pivots about the center where it is attached to the lower end of the shock strut. Tow fittings are installed on each end of the beam for forward and aft towing.
(3)
Two axles are installed in the truck beam, and are locked into place by retaining tow fittings. Four brakes are installed on protective sleeves which surround the axles. Four wheels are mounted directly on the axles.
(4)
Brake rods link each brake to the shock strut. The rods transmit brake torque to the gear.
(5)
Wire bundles on the truck beam are protected from objects thrown from the tires by a protective shield clamped underneath the truck beam.
E.
Drag Strut (Fig. 1)
__________
(1)
The drag strut absorbs forward and aft loads on the gear. The strut is a one-piece brace which forms a triangle with the trunnion link and shock strut.
(2)
The upper end attaches to the trunnion link near the forward trunnion bearing. The lower end attaches to the shock strut at the upper torsion link attachment. Fittings on the drag strut provide mounting for the main gear strut door.
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757
MAINTENANCE MANUAL
F. Side Strut and Downlock Assembly (Fig. 1)
________________________________
(1)
The side strut and downlock assembly locks the main gear into the extended position, and provides lateral support of the gear. The assembly consists of the side strut and the downlock, both of which are two-member braces which fold during extension and retraction.
(2)
The side strut consists of an upper and a lower strut hinged in the center. The lower strut attaches to a rotating swivel on the shock strut. The upper strut attaches to a universal swivel on the reaction link.
(3)
The downlock consists of an upper and a lower link, also hinged in the center. The lower link attaches to the hinge point of the side strut. The upper link attaches to a rotating spindle on the main gear jury support brace. Two downlock springs are located on the lower downlock link to aid in locking the main gear into the extended position. A downlock pin is inserted through the two links to lock the gear for safety during ground operations.
G.
Reaction Link (Fig. 1)
_____________
(1)
The reaction link transmits lateral loads from the side strut to airplane structure. The outboard end of the link attaches to the rear wing spar above the trunnion link. The inboard end attaches to a support link connected to a body frame.
H.
Fuse Pins (Fig. 1)
_________
(1)
The main gear and gear support beam are attached to the airplane wing structure at critical points by fuse pins. These fuse pins shear under extreme loads and provide a release of the gear to prevent major damage to wing structure and prevent rupturing of the fuel tanks.
(2)
There are three gear fuse pins which break to let the gear structure come apart. The first is the pin which connects the drag strut to the trunnion link. The second is the pin which connects the upper downlock link to the upper spindle. The third is a torsional fuse which connects the lower side strut to the shock strut.
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本文链接地址：757 AMM 飞机维护手册 起落架 CHAPTER 32 - LANDING GEAR 1(76)
