S 414-047
(9) Close the fueling station door, 621GB (AMM 06-44-00/201).
S 444-033
WARNING: DO THE ACTIVATION PROCEDURE FOR THE LEADING EDGE SLAT AND MOVE
_______ ALL PERSONS AND EQUIPMENT AWAY FROM THE LEADING EDGE SLATS. THE LEADING EDGE SLATS CAN MOVE QUICKLY AND CAUSE INJURY TO PERSONS OR DAMAGE TO EQUIPMENT.
(10) Do the Activation of the Leading Edge Slat procedure (AMM 27-81-00/201).
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28-21-14
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757 MAINTENANCE MANUAL
ENGINE FUEL FEED SYSTEM - DESCRIPTION/OPERATION
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1. General (Fig. 1)_______
A. Three fuel tanks (AMM 28-11-00/001) store fuel for operating the engine or APU (AMM 28-25-00/001).
B. Each engine receives fuel from the left or right main fuel tank and the center fuel tank. Opening the crossfeed valve(s) permits either engine to be supplied by any tank. An engine fuel shutoff valve controls fuel flow from each fuel tank to each engine.
C. Four electric motor driven fuel boost pumps supply fuel at pressure to the engines. Each main boost pump mounts to the forward or rear spar of the center wing fuel tank. These four boost pumps draw fuel from the main fuel tanks. In addition, each main engine fuel feed subsystem has a boost pump bypass valve to allow suction feed to the engine should a boost pump fail.
D. Two override boost pumps allow fuel feed from the center fuel tank. The pumps provide fuel to the respective left or right halves of the engine fuel feed manifold at a pressure higher than the main boost pumps. This allows the center tank fuel to be used before fuel is used from the main fuel tanks.
E. Automatic sumping jet pumps scavenge water/contaminants from the fuel tank sump areas. The jet pumps, powered by motive flow from the main boost pumps, direct the scavenged discharge to the inlet of the boost pump. The scavenge is mixed with fuel and sent to the engine.
F. A fuel scavenge ejector pump, powered by motive flow from the left forward boost pump, transfers fuel from the center tank sump area through a float valve and discharges the fuel into the left main tank. The float valve allows fuel to be discharged into the left main tank when the left main tank is less than half full.
G. The fuel management module, on the pilot's overhead panel P5, contains the control and indication for the engine fuel feed system. The Engine Indication and Crew Alerting System (EICAS) (Ref 31-41-00) also provides indication of engine fuel feed system malfunctions. The fuel control panel on the quadrant stand P10 also contains indiction of engine fuel shutoff valve malfunction.
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本文链接地址：757 AMM 飞机维护手册 燃油 CHAPTER 28 - FUEL 2(93)
