S 714-037

 (4)  
Do a check on the engage switches of the yaw damper system:

 (a)  
Set the IND LTS switch on the Pilots' Overhead Panel to the TEST position.

 (b)  
Make sure the INOP annunciators of the upper yaw damper and the lower yaw damper come on.

 (c)  
Push and release the engage switch of the upper yaw damper.

 (d)  
Make sure the ON annunciator of the upper yaw damper comes on.

 (e)  
Push and release the engage switch of the lower yaw damper.

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 22-21-01
 ALL  ú ú 04 Page 403 ú Oct 10/93
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 (f)  Make sure the ON annunciator of the lower yaw damper comes on.
 S 714-038
 (5)  Do this task: "Operational Test - Passenger Oxygen System" (AMM 35-21-00/501).
 NOTE: Do only the Prepare System for Alternate (Electrical)
____ Actuation Operational Test and Perform Alternate (Electrical) Actuation Operational Test.
 E. Airplane to Its Initial Condition
 S 864-040
 (1)  
Push and release the engage switches of the upper and the lower yaw dampers to disengage the yaw damper system.

 S 864-041

 (2)  
Set all the mode selector switches on the IRS control panel, P5, to the OFF position if it is not necessary (Ref 34-21-00/501).

 S 864-042

 (3)  
Remove electrical power if it is not necessary
 (Ref 24-22-00/201).

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 22-21-01
 ALL  ú ú 03 Page 404 ú Oct 18/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 YAW DAMPER MODULE - REMOVAL/INSTALLATION
________________________________________
 1.  General________
 A.  This procedure contains two tasks. The first task is for the removal of a yaw damper module (YDM) from the main equipment center. The second task is for the installation.
 B.  There are two YDMs. Each YDM has two front hooks which hold the YDM in position. One electrical connector is at the rear of each YDM. The procedure is the same for the upper YDM and the lower YDM.
 C.  You can find the upper YDM (M7362) on the E1-2 shelf in the main equipment center. You can find the lower YDM (M7363) on the E2-2 shelf in the main equipment center.
 TASK 22-21-02-004-042
 2.  Yaw Damper Module Removal__________________________
 A.  References
 (1)  
06-09-01/201, Body Section 41 Access Doors and Panels

 (2)  
20-11-22/401, Rack-Mounted Electrical/Electronic Module

 (3)  
IPC 22-21-02, Fig. 4

 B.  Access
 (1)  
Location Zone 117 Electrical and Electronics Compartment, LH 118 Electrical and Electronics Compartment, RH

 (2)  
Access Panel
 117AL Electronics Compartment Access Door

 C.  Procedure
 S 864-043
 (1)  
Set the FLT CONTROL HYD POWER TAIL 2 and 3 switches to the SHUTOFF position. These switches are on the Pilots' Overhead Maintenance Panel (P461).

 S 864-044

 (2)
Open these circuit breakers and attach the DO-NOT-CLOSE tags:

 (a)  P7 Overhead Circuit Breaker Panel
 1) 7C09 UPR YAW DAMPER

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 22-21-02
 ALL  ú ú 03 Page 401 ú Jun 10/93
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 2) 7C10 FLT CONT ELEC 2L AC 3) 7C11 FLT CONT ELEC 2L DC 4) 7C12 FLT CONT ELEC 1L AC 5) 7C13 FLT CONT ELEC 1L DC 6) 7C14 FLT CONT ELEC 1R AC 7) 7C15 FLT CONT ELEC 1R DC 8) 7C16 FLT CONT ELEC 2R AC 9) 7C17 FLT CONT ELEC 2R DC 10) 7C18 LWR YAW DAMPER
　
中國航空網 www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：747-400 AMM 飛機維護手冊 空調 AUTO FLIGHT(174)