07-11-02
 ALL  ú ú 01 Page 211 ú Oct 18/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 (g)  
Apply the parking brake when the airplane is at the necessary height.

 (h)  
Make sure the jack ram is locked before maintenance is done on the airplane.

 S 582-015
 (5) Lower the airplane nose off the jack. Do the steps that follow:
 CAUTION: MAKE SURE THE AREA BELOW THE AIRPLANE IS CLEAR OF ALL
_______ EQUIPMENT BEFORE THE AIRPLANE IS LOWERED. IF YOU DO NOT OBEY THESE INSTRUCTIONS, DAMAGE TO THE AIRPLANE CAN OCCUR.
 (a)  
Make sure the area below the airplane is clear.

 (b)  
Make sure the control lever for the landing gear is in the DN position.

 (c)  
Lower the jack until the jack is at the bottom or until the airplane weight is on the nose gear.

 (d)  
Move the jack away from the airplane.

 (e)  
Remove the jack adapter (Fig. 204).

 1)  Install the attach point screws for the jack adapter in the airplane structure.
 S 612-016
 (6) Deflate and do the servicing of the shock strut (AMM 12-15-05/301).
 I.  Lift the Airplane Nose at Jack Point VI with deflating the Nose Shock Strut.
 S 862-032
 (1)  Deflate the shock strut of the nose landing gear (AMM 12-15-05/301).
 S 862-018
 CAUTION: DO NOT USE THE SHOCK STRUT RETENTION TOOL ON INFLATED SHOCK
_______
 STRUTS. THE RETENTION TOOL HAS A LOAD LIMIT.

 (2)  An optional method that can be used to perform maintenance on the nose landing gear and reduce the over all jacking height to acheive nose wheel clearance is to lift the airplane nose and use the retention tool for the shock strut and the jack point VI.
 NOTE: Do this with a deflated shock strut.
____
 NOTE: Do not install the retention tool when the nose landing gear
____
 is going to be retracted.

 (a)  Install the retention tool.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 07-11-02
 ALL  ú ú 02 Page 212 ú Oct 18/01
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 S 582-020
 (3)  To lift the airplane nose, do the steps that follow:
 (a)  
Remove the attach point screws of the jack adapter at jack point VI (Fig. 203).

 (b)  
Install the jack adapter (Fig. 204).

 CAUTION: MAKE SURE THE JACK IS IN THE CENTER BELOW THE JACK
_______ ADAPTER. IF THE JACK IS NOT IN THE CENTER BELOW THE JACK ADAPTER, DAMAGE TO THE JACK OR THE AIRPLANE CAN OCCUR.
 (c)  Put the jack directly below the jack adapter at jack points VI. Turn the jack so that a line between aft two jack footpads is vertical to the airplane centerline. Make sure the jack is in the center below the jack adapter.
 CAUTION: DO NOT LIFT THE NOSE OF THE AIRPLANE MORE THAN SIX INCHES
_______ OF TIRE CLEARANCE. IF YOU LIFT THE NOSE HIGHER, SIDE LOADS THAT ARE MORE THAN DESIGN LOAD LIMITS CAN OCCUR. THIS CAN CAUSE DAMAGE TO THE JACK RAM AND JACK ADAPTER BECAUSE THEY WILL MOVE IN AN ARC.
 (d)  
Lift the nose to the necessary height, but not more than 6 inches.

 (e)  
Make sure the jack ram is locked before maintenance is done to the airplane.

 S 582-021
 (4)  Lower the airplane nose off the jack. Do the steps that follow:
 (a)  
Make sure the area below the airplane is clear.

 (b)  
Make sure the control lever for the landing gear is in the DN position.

 (c)  
Lower the jack until the jack is at the bottom or until the airplane weight is on the nose gear.

 (d)  
Move the jack away from the airplane.

 (e)  
Remove the jack adapter (Fig. 204).

 (f)  
Install the attach point screws for the jack adapter in the airplane structure.
　
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