S 862-036

 (2)
Remove the DO-NOT-CLOSE tags and close these circuit breakers:

 (a)  
P7, Overhead Circuit Breaker Panel

 1)  For the lower rudder ratio changer, a) 7B14, LWR RUD RATIO AC PWR b) 7B15, LWR RUD RATIO DC PWR
 2)  For the upper rudder ratio changer, a) 7B12, UPR RUD RATIO AC PWR b) 7B13 UPR RUD RATIO DC PWR
 (b)  
P180 DC Power Distribution Panel
 1) 180E7 ELEV/RUD VLV SYS 2
 2) 180E22 ELEV/RUD VLV SYS 4
 3) 180H8 ELEV/RUD VLV SYS 1
 4) 180H23 ELEV/RUD VLV SYS 3

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

 S 862-058

 (4)  
Find the switches for the FLT CONTROL HYD POWER on the Pilot's Overhead Maintenance Panel, P461.

 (a)  
Put the four TAIL switches in the NORM position.

 (5)  
Do a test of the rudder ratio changer (AMM 27-21-12/501).

 S 862-041
 S 712-039
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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 RUDDER RATIO CHANGER - ADJUSTMENT/TEST
______________________________________
 1.  General_______
 A.  This procedure has two tasks. The first task is to adjust the rudder ratio changer. The second task is to do a test of the rudder ratio changer. To do a test of the rudder ratio changer you must use EICAS.
 B.  The airplane can not be on jacks when you do these procedures. A jack at the tail jack point III is permitted, if the load on the jack point is a maximum of 2000 pounds.
 TASK 27-21-12-835-001
 2.  Rudder Ratio Changer Adjustment (Fig. 501)_______________________________
 A.  Special Tools and Equipment
 (1)
G12001-50 Rig Pin Kit

 B.  
Standard Tools and Equipment

 (1)
Pitot-Static Test Equipment

 C.  
References

 (1)
06-09-05/201, Body Section 48 Access Doors and Panels

 (2)
06-09-07/201, Fin and Rudder Access Doors and Panels

 (3)
09-11-00/201, Towing

 (4)
24-22-00/201, Manual Control

 (5)
27-21-00/524, Procedure 1

 (6)
27-21-15/501, Upper Rudder Power Control Actuator

 (7)
27-21-16/501, Lower Rudder Power Control Actuator

 (8)
29-11-00/201, Main Hydraulic Supply System

 (9)
34-11-00/201, Pitot-Static System

 (10)
 IPC 27-21-12, Fig. 3

 D.  
Access

 (1)  
Location Zone 324 Vertical Fin, Rear Spar to Trailing Edge 325 Lower Rudder 326 Upper Rudder

 (2)  
Access Panel 315A Access Door 324DL Inspection Access Panel 324FL Centering and Feel Mechanism Access Panel 324UL Inspection Access Panel

 E.  
Prepare for the Adjustment

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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

ACTUATOR POWER CONTROL  MODULE POWER CONTROL 
ASEE CONTROL PACKAGE UPPER POWER  RUDDER RATIO CHANGER 
SEE AND TRIM MECHANISM FEEL, CENTERING  E 
SEE  B 
CONTROL PACKAGE LOWER POWER 
SEE  D 
ACTUATOR POWER CONTROL 
RIG PIN E-2 
SEE  F 

UPPER POWER CONTROL PACKAGE
A INPUT ROD FOR THE UPPER RUDDER
RUDDER TRIM
RATIO CHANGER ACTUATOR
ROD ADJUSTMENT 
FEEL, CENTERING 
SEE  C  AND TRIM 
MECHANISM 
RUDDER AFT 
QUADRANT 

CLAMP BOLT
KNURLED LOCKNUT
ADJUSTER
ROD ADJUSTMENT C
FEEL, CENTERING AND TRIM MECHANISM B Rudder Ratio Changer Adjustment Figure 501 (Sheet 1)
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