Aileron and Aileron Trim Control System - Component Location Figure 2 (Sheet 5)
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MAINTENANCE MANUAL
A-A
AILERON DOWN 20` HONEYCOMB B-B
Ailerons - Mechanism Components
Figure 3 (Sheet 1)
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MAINTENANCE MANUAL
ACTUATOR
HINGE SPT (TYP)
D-D
Ailerons - Mechanism Components
Figure 3 (Sheet 2)
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MAINTENANCE MANUAL
C. The aileron control load limiter is located at the base of the first officer's control column. The load limiter consists of a bus drum, an aileron control drum, a shaft with integral cam, and a roller and preloaded torsion spring mechanism. The bus drum and aileron drum above it are bearing-mounted on the same shaft. Spring-induced compression maintains the roller in a cam surface detent on the shaft. In effect, the shaft and bus drum are locked together. Rotation of bus drum causes rotation of shaft. Shaft rotation, in turn, produces aileron movement. To free the shaft, sufficient rotational force must be applied at the first officer's control wheel to force the roller out of the cam detent.
D. If the left body control cables should become jammed, the captain's control wheel will become inoperable and the first officer's control wheel must be used to maintain lateral flight control. Additionally, each attempt to rotate this wheel out of its neutral position will require application of substantially greater force than normal. This force (approximately 26 pounds) will overcome the coupling of the two control wheels and allow the first officer's wheel to operate the ailerons through the right body control cables.
E. The lost motion feature is provided by a device in the load limiter which permits motion of the control wheel bus drum with respect to the load limiter drum within certain mechanical stop limitations. The lost motion feature is required because lost motion causes system lag through the cable system and power packages which causes the right body cables to be slightly out of phase with the control wheels. Up to | 6 degree system lag is permitted without causing any input to the aileron control wheels.
4. Aileron Trim and Feel Mechanism (Fig. 2)
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A. The aileron trim and feel mechanism provides artificial feel at the aileron control wheels, and centering and trim of the lateral control system. The mechanism receives its input from the left body control cables and provides an output which operates the CLCPs.
B. Rotation of the left body input quadrant rotates a cam mounted on the same shaft as the quadrant. This motion forces a cam follower out of a neutral detent position. Two centering and feel springs connected to the cam follower extend and provide the force felt at the control wheels. When the control wheels are released, the spring force, operating through the cam follower, forces the cam back to the neutral position, centering the system. A pushrod connected to the quadrant provides the input to the CLCPs.
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27-11-00 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：747-400 AMM 飞机维护手册 飞行操纵 FLIGHT CONTROLS 1(46)
