(a)
If procedure 1 was used to extend the actuator, push the LSK that is adjacent to END TEST> on the CDU.
(b)
If procedure 2 was used to extend the actuator, slowly release the pressure from the pitot-static system (Ref/34-11-00/201).
S 225-020
(8)
Look at the bottom of the trailing edge of the lower rudder.
(a)
If the trailing edge is not in the width of the index tab, adjust the power control actuator for the lower rudder (Ref 27-21-16/501).
G.
Upper Rudder Ratio Changer Adjustment
S 865-022
(1)
Remove the DO-NOT-CLOSE tags and close these circuit breakers:
(a)
P180, DC Power Distribution Panel
1) 180H8, ELEV/RUD VLV SYS 1
2) 180H23, ELEV/RUD VLV SYS 3
S 865-040
(2)
Find the switches for the FLT CONTROL HYD POWER on the pilot's overhead maintenance panel, P461:
(a)
Put the No. 1 and No. 3 tail switches in the NORM position.
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(b) Put the No. 2 and No. 4 tail switches in the SHUTOFF position.
S 865-023
(3)
Open these circuit breakers and attach DO-NOT-CLOSE tags:
(a)
P180, DC Power Distribution Panel
1) 180E7, ELEV/RUD VLV SYS 2
2) 180E22, ELEV/RUD VLV SYS 4
S 865-051
WARNING: MAKE SURE THAT PERSONS AND EQUIPMENT ARE CLEAR OF ALL CONTROL
_______ SURFACES BEFORE YOU SUPPLY HYDRAULIC POWER. AILERONS, RUDDERS, ELEVATORS, FLAPS, SPOILERS, LANDING GEAR, AND THRUST REVERSERS CAN MOVE QUICKLY WHEN YOU SUPPLY HYDRAULIC POWER. THIS CAN CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMENT.
(4)
Supply hydraulic power to systems No. 1 and No. 3 (Ref 29-11-00/201).
S 845-065
(5)
Do one of the two subsequent procedures to extend the servo units for the two rudder ratio changers.
(a)
Procedure 1 (for airplanes with two SRM's P/N 285U0015-108 or later), see procedure 1 (AMM 27-21-00/524).
WARNING:_______MAKE SURE THE FLAPS ARE RETRACTED. IF THE FLAPS ARE NOT RETRACTED, THEY CAN MOVE WHEN YOU PRESSURIZE THE PITOT-STATIC SYSTEM. THIS CAN CAUSE INJURY TO PERSONS OR DAMAGE TO EQUIPMENT.
(b)
Procedure 2 (airplanes with any combination of SRM part numbers istalled), supply a 3.37-3.52 psig pressure (363-371 knots) to the pitot port of the top right and the top left pitot probes (AMM 34-11-00/201).
NOTE: This extends the servo unit of the rudder ratio changer.
____ The left and the right pitot probes must be pressurized at the same time. If they are not, the SRM will set the comparison fault on the Digital Air Data Computer (DADC). This stops the rudder ratio changer.
(c) If the trailing edge of the rudder moves more than 0.06 inch, adjust the input rod for the rudder ratio changer. 1) If the rudder moved in a right direction when you
pressurized the pitot system , make the input rod shorter. If the rudder moved in a left direction when you pressurized the pitot system, make the input rod longer.
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(d) Large adjustment:
1) Find the switches for the FLT CONTROL HYD POWER on the pilot's overhead maintenance panel, P461: a) Put the No. 1 and No. 3 tail switches in the SHUTOFF
position.
2) Open these circuit breakers on the DC Power Distribution Panel, P180, and attach DO-NOT-CLOSE tags: a) 180H8, ELEV/RUD VLV SYS 1 b) 180H23, ELEV/RUD VLV SYS 3
3) Loosen the clamp bolt on the input rod.
NOTE: This is at the feel, centering, and trim end of the
____
input rod.
4) Loosen the locknuts on the input rod. 5) Disconnect the input rod from the output crank of the feel, centering, and trim mechanism. 6) Turn the rod end or the knurled adjuster nut. 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 飞行操纵 FLIGHT CONTROLS 2(123)
