G08967
500 Elevator Power Control Switches
Feb 15/73 Figure 201 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 27-31-0 Page 203
4. Elevator Hydraulic Systems A and B Pressurization
A. Pressurize elevator hydraulic systems A and B.
(1)
Install ground lock assembly in nose gear.
(2)
Set parking brake.
(3)
Provide electrical power.
(4)
Position No. 1 or 2 hydraulic system B pump switch, located in center of forward overhead panel to ON.
(5)
Position ground interconnect switch on forward overhead panel to OPEN.
(6)
Close flight controls circuit breakers on panel P6.
(7)
Position flight controls hydraulic systems A and B switches on overhead panel to ON.
NOTE: To energize only one elevator hydraulic system, select by positioning of these switches.
B. Restore airplane to normal.
NOTE: Perform following steps after completing elevator control system maintenance that required pressurization.
(1)
Position No. 1 and 2 hydraulic system B pump switches to OFF.
(2)
Position ground interconnect switch to CLOSE.
(3)
Position flight controls hydraulic systems A and B switches to ON.
(4)
Remove electrical power, if no longer required.
(5)
Remove ground lock assembly from nose gear.
5. Mach Trim Actuator Null Procedure (for elevator system rigging)
A. Insert one mach trim actuator checking bar pin into hole in actuator and rest other pin in bolt head dimple as shown in Fig. 203. If pin can be inserted, actuator is in null position. If actuator is not in null position, use steps B thru J to null actuator.
B. Provide electrical power.
C. Check that mach trim and air data No. 1 circuit breakers on panel P6 are closed.
D. Check that electrical connector is connected to mach trim actuator.
501
27-31-0 Page 204 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. Oct 20/84
G08666
500 Flight Control Hydraulic Modular Lock Installation
Feb 15/73 Figure 202 27-31-0
Page 205
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
E. On E1-2 shelf in electrical and electronics compartment, connect VTVM to TP-6 (linear synchro feedback) and TP-4 (signal ground) on mach trim coupler with VTVM set to 10-volt ac scale.
F. Place self-test switch of mach trim coupler to position 1 for minimum of 10 seconds. Check that VTVM indicates a reading greater than 4.5 volts ac.
G. Position self-test switch to OFF.
H. Press RESET button on mach trim coupler, intermittently if necessary, to obtain a null on VTVM (100 mv ac maximum).
NOTE: If overshoot should occur, repeat the above procedure. Mach Trim Actuator null position can be verified by inserting mach trim actuator checking bar pins into actuator hole as shown in Fig. 203.
If the mach trim actuator checking bar pin does not align with the bolt head dimple, it can be necessary to replace the mach trim actuator or the M412 mach trim coupler.
I. Disconnect VTVM from mach trim coupler.
J. Open all circuit breakers closed in step C.
NOTE: Following maintenance practices during which circuit breakers in step C were left open, ensure that same circuit breakers are closed.
500
27-31-0 Page 206 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. Aug 01/94
G08671
500 Elevator Mach Trim Actuator Checking Bar Installation
Nov 15/78 Figure 203 27-31-0
Page 207
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
ELEVATOR AND TAB CONTROL SYSTEM -ADJUSTMENT/TEST
1. Elevator and Tab Control System Adjustment
A. General
(1)
The elevator control system (Fig. 501) is adjusted to synchronize control surfaces and components to the neutral position. Rigging pins assist adjustment of the control system by locking the forward and aft control quadrants in their respective neutral positions. The following procedures adjust the system from fore to aft, giving precedence to major components within the system.
WARNING: ALL FLIGHT CONTROL SYSTEMS ARE FULLY POWERED. CHECK TO ENSURE THAT PERSONNEL AND OBSTRUCTIONS ARE CLEAR OF ALL CONTROL SURFACES BEFORE TURNING HYDRAULIC POWER ON.
(2)
When new elevator control cables are installed in the airplane, cables should be overtensioned and cycled to assist seating in pulleys and quadrants. Tension cables to twice the value specified in Fig. 501 and cycle system 25 times through full travel.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：737 AMM 飞机维护手册 飞行操纵 FLIGHT CONTROLS 2(61)
