S 585-107
(6)
Move the airplane forward a few feet so that all tires are off the scales.
S 945-015
(7)
Make sure that the scales are set up and tared so that each scale reads between -25 and +25 lbs.
S 585-021
(8)
Move the airplane onto the scales again.
(a) Make sure that there is a 3-inch clearance between the tire footprints and the edges of the scales.
S 865-133
(9)
Make sure that the parking brake is set and the tow bar is disconnected.
S 865-111
(10)
Remove the pressure from hydraulic systems 1 and 4 (AMM 29-11-00/201).
S 015-094
(11)
Disconnect the truck positioning actuator on each wing landing gear (AMM 32-11-20/401).
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
31-41-00
ALL ú ú 05S Page 507 ú Feb 18/01
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL
S 945-022
(12)
Make sure that no extra equipment is attached to the airplane.
S 865-023
(13)
Make sure that persons inside the airplane do not move around when you collect data.
NOTE:____These steps are important for the calibration. The first step makes sure that strut pressures can change in a DIMENSION X tolerance. The second step makes sure that the airplane is balanced in its roll axis with a necessary wheel weight. This is done by making sure truck weight differences are less than 8,000 lbs with nose wheel weight differences less than 2,000 lbs.
S 865-018
(14) Adjust the inflation pressures of the wing and body landing gear shock struts so that DIMENSION is between 22 and 24 inches (see the shock strut servicing charts near the struts).
(a)
If strut inflation is necessary to meet the specified DIMENSION X, then the body landing gear shock strut pair should be inflated to the specified value before the wing landing gear pair.
(b)
If strut deflation is necessary to meet the specified DIMENSION X, then the wing landing gear shock strut pair should be deflated to the specified value before the body landing gear pair.
(c)
Calculate the total weight on each main landing gear truck from the scales. 1) Make sure that the highest and lowest total truck weights
are not more than 8000 lbs. apart.
2) If the highest and lowest total truck weights are more than 8000 lbs apart, adjust the shock strut pressures while you make sure that the value of DIMENSION X stays between 22 and 24 inches.
NOTE: Increasing strut pressure increases the weight on
____ the wheels of that strut, while decreasing the weight on the wheels of other struts.
(d) Read the weight on each nose wheel from the scales.
NOTE: Total nose wheel weight must be 21,000 to 27,000 lbs.
____
1) Make sure that the two nose wheel weights are not more than 2000 lbs. apart.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
31-41-00
ALL ú ú 05S Page 508 ú Feb 18/01
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL
2) If the two nose wheel weights are more than 2000 lbs apart, adjust the nose wheel tire pressures to get a difference between nose wheel weights of less than 2000 lbs while remaining within allowable in-service tire limits.
NOTE: Increaseing tire pressure increases the weight on
____ that nose wheel, while decreasing the weight on the opposite nose wheel.
(e) If the nose wheel tire pressures cannot be set within allowable limits to achieve nose wheel weights within 2000 lbs, do these steps. 1) Maintain nose wheel tire pressures at the last in-service
maximum.
2) Adjust the wing and body gear shock struct pressures within allowable limits (make sure DIMENSION X stays between 22 and 24 inches) until the difference in nose wheel weight is less than 2000 lbs.
G. Record the Load Sensor Counts (Mode-22)
S 745-024
(1) Do these steps to use mode 22 of the WBC to read load sensor counts:
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：747-400 AMM 飞机维护手册 指示/记录系统 1(89)
