2) For the upper rudder ratio changer,
a) 7B12, UPR RUD RATIO AC POWER
b) 7B13, UPPER 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
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747-400
MAINTENANCE MANUAL
4) 180H23, ELEV/RUD VLV SYS 3
S 862-053
(9)
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.
S 832-026
(10) Adjust and do a test on the rudder ratio changer (AMM 27-21-12/501).
TASK 27-21-12-002-060
5. Ratio Changer Servo Removal (Fig. 202)
___________________________
A. Special Tools and Equipment
(1)
G12001-50, Rig Pin Kit
B.
References
(1)
AMM 06-09-07/201, Fin and Rudder Access Doors and Panels
(2)
AMM 24-22-00/201, Manual Control
(3)
AIPC 27-21-12, Fig. 3
(4)
AIPC 27-21-15, Fig. 2
(5)
WDM 27-21-12
C.
Access
(1)
Location Zone 324 Vertical Fin, Rear Spar to Trailing Edge 325 Lower Rudder 326 Upper Rudder
(2)
Access Panel 324DL Inspection Access PAnel 324FL Centering and Feel Mechanism Access Panel 324UL Inspection Access Panel
D.
Prepare for the Removal
S 862-049
(1)
Supply electrical power (AMM 24-22-00/201).
S 862-054
(2)
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 SHUTOFF position.
S 862-027
(3)
Open these circuit breakers and attach DO-NOT-CLOSE tags:
(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
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú
27-21-12
ALL ú ú 01 Page 211 ú Feb 18/01
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
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
S 012-055
(4)
Remove the access panels 324FL and 324DL to get access to the lower rudder ratio changer (RRC)(AMM 06-09-07/201).
S 012-056
(5)
Remove the access panels 324FL and 324UL to get access to the upper RRC (AMM 06-09-07/201).
S 492-029
(6)
Install the rig pin R-4 in the feel, centering, and trim mechanism.
E.
Remove the Ratio Changer Servo
S 032-030
(1)
Disconnect the electrical connector (4) from the ratio changer servo (5).
S 032-031
(2)
Disconnect the bonding jumper (6) from the ratio changer servo (5).
S 032-032
(3)
Hold the ratio changer servo (5) and disconnect it from the trunnion crank.
(a)
Remove the bolt (15), the washer (16), and the nut (13).
S 032-033
(4)
Disconnect the ratio changer servo (5) from its fitting.
(a)
Remove the bolt (10), washer (12), and nut (13).
(5)
Remove the ratio changer servo (5) from the RRC.
S 022-034
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本文链接地址：747-400 AMM 飞机维护手册 飞行操纵 FLIGHT CONTROLS 2(118)
