07-11-02
 ALL  ú ú 01 Page 208 ú Jun 18/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

SEE B VI II
I SEE A
FWD  INTEGRAL JACK PAD
JACK (ACCESS PANEL REMOVED)
BODY INTEGRAL JACK PAD (I & II) A
JACK ADAPTER 36MIT65B00141
FWD
FWD JACK
FORWARD BODY (NOSE) JACK ADAPTER (VI) B
Jacking Points Figure 204
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 07-11-02
 ALL  ú ú 01 Page 209 ú Feb 15/99
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
 (f)  Remove the optional nose landing gear shock strut retention tool if it was installed.
 S 612-010
 (5)  Do the servicing of the shock strut on the nose landing gear (AMM 12-15-05/301).
 H. Extend the Nose Shock Strut and Lift the Airplane Nose at Jack Point VI.
 S 862-011
 (1)  Put the nose landing gear in the center position (AMM 32-51-00/501).
 S 862-024
 CAUTION: MAKE SURE THE AREA BELOW THE AIRPLANE IS CLEAR OF ALL EQUIPMENT
_______ BEFORE THE SHOCK STRUT IS DEFLATED. IF YOU DO NOT OBEY THESE INSTRUCTION, DAMAGE TO THE AIRPLANE CAN OCCUR.
 (2)  Deflate the shock strut of the nose landing gear (AMM 12-15-05/301).
 S 862-030
 CAUTION:_______PUT HYDRAULIC FLUID IN THE STRUT TO EXTEND THE STRUT. DO NOT USE AIR OR NITROGEN BECAUSE TOO MUCH PRESSURE CAN CAUSE DAMAGE TO THE STRUT AT ITS FULL EXTENSION.
 MAKE SURE YOU EXTEND THE NOSE STRUT BEFORE THE AIRPLANE IS LIFTED AT JACK POINT VI. WHEN THE NOSE IS LIFTED INDEPENDENTLY AND SUFFICIENTLY FOR TIRE CLEARANCE, UNUSUAL LOADS ARE CAUSED. JACK POINT VI WILL MOVE IN AN ARC ABOUT 3-1/2 INCHES AFT AND CAUSE LOADS THAT ARE MORE THAN THE DESIGN LIMITS. THE BEND FORCE OF THE JACK RAM IS LESS THAN THE BREAKAWAY FORCE THAT IS NECESSARY TO MOVE THE 16 MAIN LANDING GEAR TIRES. DURING SOME CONDITIONS, JACK DAMAGE AND DAMAGE TO THE AIRPLANE CAN OCCUR. THIS COULD MAKE THE RETRACTION OF THE JACK RAM NOT EASY OR NOT POSSIBLE.
 (3)  To inflate the shock strut of the nose landing gear with the correct servicing fluid, do the steps that follow (AMM 12-15-05/301):
 (a)  Connect a 0-3000 psi pressure gage to the air charging valve.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 07-11-02
 ALL  ú ú 03 Page 210 ú Oct 18/01
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

 WARNING:_______DO NOT INFLATE THE SHOCK STRUT TO MORE THAN 2000 PSI. IF THE SHOCK STRUT IS INFLATED TO MORE THAN 2000 PSI, INJURY TO PERSONS CAN OCCUR. DAMAGE TO THE NOSE LANDING GEAR CAN ALSO OCCUR.
 CAUTION: DO NOT INFLATE THE NOSE GEAR SHOCK STRUT TO AN "A"
_______ DIMENSION MORE THAN 24.5 INCHES. IF THE "A" DIMENSION IS MORE THAN 24.5 INCHES, DAMAGE TO THE SEALS CAN OCCUR.
 (b)  
Put the correct servicing fluid into the strut with a pump. Do this until it is extended to a dimension "A" of 23.5 to 24.5 inches.

 (c)  
Close the air charge valve and remove the pressure gage.

 S 582-013
 (4)  Lift the airplane nose to the necessary height.
 (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 until a line between the aft two jack footpads is vertical to the airplane centerline. Make sure the jack is in the center below the jack adapter.

 (d)  
Release the parking brake.

 (e)  
Move the forward wheel chocks at the main gear, forward of the tires about 3-1/2 inches from tires.

 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.
　
中國航空網(wǎng) www.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：747-400 AMM 飛機(jī)維護(hù)手冊 LIFTING AND SHORING(10)