S 864-017
(2)
Supply the electrical power (Ref 24-22-00/201).
(3)
Make sure the EICAS is serviceable (Ref 31-61-00/201).
S 864-033
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(4) S 864-018Put the FLT CONTROL HYD POWER - TAIL switches No. 1, 2 and 3 on the P461 Pilots' Overhead Maintenance Panel in the SHUTOFF position.
(5) S 864-019Pressurize the hydraulic system No. 4 (Ref 29-11-00/201).
S 714-020
CAUTION:_______MOVE THE RUDDER PEDALS SLOWLY AND SMOOTHLY. THE MINIMUM TIME TO MOVE THE RUDDER THROUGH A FULL CYCLE IS 8 SECONDS. IF YOU MOVE THE RUDDER TOO QUICKLY, THE POWER CONTROL PACKAGES CAN BE DAMAGED.
(6)
Do a test of the operation of the hydraulic fuse:
(a)
Push the rudder pedals to move the rudder fully left and right two times.
(b)
Make sure the EICAS shows that the rudder moves to the correct position.
S 864-021
(7)
Remove the system No. 4 hydraulic power if it is not necessary (Ref 29-11-00/201).
S 864-022
(8)
Put the FLT CONTROL HYD POWER - TAIL switches No. 1, 2 and 3 on the P461 Pilots' Overhead Maintenance Panel in the NORM position.
S 794-023
(9)
Examine the hydraulic fuse for leakage of hydraulic fluid.
NOTE: Leakage check is not necessary if you have not removed and/or
____ installed the hydraulic fuse.
S 094-027
WARNING:_______MAKE SURE THE NOSE WHEELS POINT FORWARD. IF THE NOSE WHEELS DO NOT POINT FORWARD, THE NOSE GEAR CAN QUICKLY TURN TO THE CENTERED POSITION WHEN YOU REMOVE THE TOW PIN. THIS CAN CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMENT.
(10)
Remove the TOW PIN from the nose landing gear (Ref 09-11-00/201).
S 864-025
(11)
Remove the electrical power if it is not necessary (Ref 24-22-00/201).
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RUDDER AND ELEVATOR HYDRAULIC SUPPLY SHUTOFF VALVE - DISCRIPTION AND OPERATION
______________________________________________________________________________
1. General_______
A. A rudder and elevator hydraulic supply shutoff valve is provided in each of the four airplane hydraulic systems to shut off hydraulic pressure to the rudder and elevator power control packages. Each system shutoff valve consists of a guarded switch on the pilot's overhead maintenance panel and a dc motor operated shutoff valve assembly located in the stabilizer jackscrew compartment. The four shutoff valve switches and the position indicator light are parts of the FLT CONTROL HYD POWER -TAIL VALVE on P461 Pilot's Overhead Maintenance Panel.
2. Rudder and Elevator Hydraulic Supply Shutoff Valve__________________________________________________
A. The shutoff valve assembly consists of two position valve driven by a dc motor powered by the airplane 28 volt dc electrical system. A double seal isolates the oil chamber of the valve from the electrical units. A manual override and position indicator lever provides a visual indication of valve position.
B. Two limit switches in the shutoff valve electrical circuits limit motor operation. The switches operate so that regardless of valve position in the operating cycle, or whether the position has been reached manually or electrically, operation of the appropriate FLT CONTROL HYD POWER - TAIL VALVE switch applies electrical power to the motor to drive the valve in selected position.
C. The shutoff valve also incorporates a switch to sense valve slide position. The slide operates the switch to complete an indicator light circuit when valve is not fully open. An indicator light is located on P461 Pilot's Overhead Maintenance Panel adjacent to each FLT CONTROL HYD POWER - TAIL VALVE switch. The light is marked VALVE CLOSED (Fig. 2).
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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(159)
