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A
747-400
MAINTENANCE MANUAL

MAIN E/E EQUIPMENT CENTER
A
Main Deck E/E Bay Extention Ladder
Figure 201 (Sheet 1)

F51582
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747-400
MAINTENANCE MANUAL

PIN SAFETY 
ROPE 
PIN 
PIN SAFETY 
PIN 
RUNG ASSEMBLY 
C
UPPER LADDER 
ASSEMBLY 

FIXED RUNG ASSEMBLY
LADDER
SEE C
LOWER LADDER ASSEMBLY
STOWAGE EXTERNAL ACCESS LADDER
B
RUNG ASSEMBLY
SEE C
Main Deck E/E Bay Extention Ladder Figure 201 (Sheet 2)
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747-400 MAINTENANCE MANUAL
 MAIN EQUIPMENT CENTER EXTENSION LADDER - MAINTENANCE PRACTICES
______________________________________________________________
 1.  General_______
 A.  This procedure contains these tasks:
 (1)  
A task to extend the extension ladder for the main equipment center.

 (2)  
A task to retract the extension ladder for the main equipment center.

 B.  The extension ladder for the main equipment center is installed to the right of a fixed ladder.
 C.  Use the fixed ladder to get access to the equipment center from the main deck. Use the extension ladder to get access to the equipment center from the ground.
 TASK 25-51-02-912-001
 2.  How to Extend the Main Equipment Center Extension Ladder (Fig. 201)________________________________________________________
 A.  General
 (1)  Two persons are needed to do this task. One person must be inside the main equipment center, the other one must be on the ground.
 B.  Access
 (1)  
Location Zones 117 Electrical & Electronics Compartment, Left 118 Electrical & Electronics Compartment, Right

 (2)  
Access Panels
 117AL Electronic Compartment Access Door

 C.  Procedure
 S 012-002
 (1)  Open the electronic compartment access door, 117AL.
 S 912-003
 WARNING: HOLD ON TO BOTH PARTS OF THE LADDER WHEN YOU MOVE IT OVER THE
_______ ACCESS DOOR OPENING. DO NOT STAND ON THE LADDER UNTIL IT IS FULLY EXTENDED, THE UPPER SAFETY PINS ARE INSTALLED IN THE PIN HOLE BRACKETS, AND IT IS TIGHTLY AGAINST THE GROUND. IF YOU DO NOT OBEY THESE STEPS, INJURY TO PERSONS OR DAMAGE TO EQUIPMENT CAN OCCUR.
 (2)  Do these steps to extend the ladder:
 (a)  
Lift up on both the upper and lower parts of the ladder to release it from the stowed position.

 (b)  
Move the upper and lower ladder assembly over the access door opening.

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 (c)  
Pull the rope at the bottom of the lower ladder assembly to release the lower safety pins from the pin hole brackets.

 (d)  
Carefully move the bottom part of the lower ladder assembly down to the extended position.

 (e)  
Pull the rope on the upper safety pins then release it to put the pins into the pin hole brackets.

 (f)  
Move the extended ladder down until it is tightly against the ground.

 TASK 25-51-02-912-004
 3.  How to Retract the Main Equipment Center Extension Ladder (Fig. 201)_________________________________________________________
　
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