HYDRAULIC ISOLATION SHUTOFF VALVES
"A" SYSTEM "B" SYSTEM
MODULE
PRESSURE PRESSURE MODULAR MODULAR PACKAGE PACKAGE
FROM AILERON FROM AILERON TO "A" COMPENSATOR COMPENSATOR
POWER UNIT "A" POWER UNIT "B" SYSTEM
TO "B" RETURN
SYSTEM
RUDDER HYDRAULIC SYSTEM A AND B SCHEMATIC
RETURN 1
NOT INSTALLED ON ALL AIRPLANES (SB 27A1206)
Rudder Hydraulic System Schematic Figure 9
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27-21-00
ALL ú ú 01 Page 17 ú Jul 12/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
737-300/400/500MAINTENANCE MANUAL
C. If hydraulic systems A and B are not available to power the rudder, standby power may be turned on, and the rudder operated with the standby actuator. Rudder pedal input positions a servovalve in the actuator which ports fluid to the actuating piston. Movement of the piston closes off the ports when desired rudder travel is reached. The rudder will also operate automatically on standby power when all of these conditions occur: system A or B hydraulic pressure drops below 1200 psi, the flaps are extended, and the wheel speed is greater than 60 knots or the airplane is in the air.
D. In addition to operating the rudder power unit and the standby actuator, the torque tube moves the centering cam in the feel and centering mechanism. When the cam shaft is rotated, the spring-loaded cam follower is displaced.
E. If rudder trim is adjusted with the power control unit depressurized, the drag of the unpowered rudder system will allow the system to remain out of center. This will force the rudder feel and centering mechanism cam follower out of the cam detent. Then when hydraulic power is applied, the rudder pedals and rudder will rapidly move to the newly trimmed position.
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27-21-00
ALL ú ú 01 Page 18 ú Jul 12/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
737-300/400/500MAINTENANCE MANUAL
RUDDER AND RUDDER TRIM CONTROL SYSTEM - TROUBLE SHOOTING
1. Rudder and Rudder Trim Control System Trouble Shooting Chart____________________________________________________________
TROUBLE PROBABLE CAUSE ISOLATION PROCEDURE REMEDY
Insufficient rudder or rudder pedal travel *[1] Foreign objects interfering with rudder pedals and forward quadrants Rudder pedals and/or forward quadrants out of rig Binding, worn or defective parts in forward quadrants Binding, worn or defective parts in rudder pedal assembly Foreign objects interfering with aft rudder quad-rant, torque tube in fin or input linkage to power control unit Fwd quadrant stops incorrectly installed Insufficient clearance between input rods or linkages and cranks or quad-rants near full travel positions Check for foreign objects in area of rudder pedals and forward quadrants Check rudder pedal and/or forward quadrant rigging. Refer to 27-21-00, Rudder and Rudder Trim Control System - A/T Check forward quadrant parts Isolate rudder pedal as-sembly and check terminal and bellcrank. Refer to 27-21-31, Rudder Pedal Assemblies - R/I Check for foreign objects in area of aft quadrants, torque tube and PCU input linkage Check if quadrant is con-tacting stops before re-quired travel is obtained With rudder pedals near full travel position, check for clearance between rods and cranks, etc. Fwd stops should be contacted before linkages run out of travel Remove foreign object Adjust rudder pedals and/or forward quadrants as necessary Replace worn or defective parts Replace worn or defective parts Remove foreign object or inter-ference Remove inter-ference Correct improper installation
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本文链接地址：737-300 400 500 AMM 飞机维护手册 飞行操纵 FLIGHT CONTROLS 2(11)
