Fuel System Flashcards
How is the Center Wing Tank Fuel Scavenged?
CWT fuel is scavenged by 4 jet pumps pumping into main tanks 2 and 3
Begins when main tank 2 or 3 fuel quantity decreases to approximately 27,200 kgs.
Which cross-feed valves are controlled by fuel system management logic when setting T/O flaps?
Crossfeed valves 2 and 3
During the before start procedure, at what center wing tank quantity are you required to select the center wing pump on?
Quantity lbs for the LCF?
7,700 kgs or more in the center wing tank
17,000lbs or more in the center wing tank
Main tank 2 and 3 override / jettison pumps can operate to a stand pipe level of approximately….
___Kgs (400)
___Kgs (-8)
___Lbs (LCF)
3,200 kgs
3,450 kgs
7000 lbs
Describe how the fuel quantity indication changes upon termination of fuel jettison:
-The fuel to remain quantity indication changes from magenta to white
-The fuel to remain quantity flashes for 5 seconds
How does the center wing tank fuel scavenge in the 400/-8?
Scavenge begins when main tank 2 or 3 fuel quantity decreases to approximately 27,200 kgs
How does center wing tank fuel scavenge in the LCF?
-CWT electric pump into M2 tank when CWT override/jettison pump has low pressure
-Fuel quantity in M2 or M3 tank is below 40,200 lbs
-Pump will operate for approximately two hours or until scavenge pump pressure is low, whichever occurs first
State what occurs when you select the fuel jettison switch to A or B
1) Arms the jettison selector
2) Displays preselected fuel to remain on EICAS
What is the impact on the aircraft with excessive fuel imbalance?
1) Adversely affects CG
2) Aerodynamic drag
3) Fuel economy
When do the FSMCs open the reserve transfer valves on the:
1)400
2)-8
3)LCF
1)When main tank 2 or 3 fuel quantity decreases to approximately 18,200 kgs
2)When main tank 1 or 4 fuel quantity decreases to approximately 6100 KGS
3)When main tank 2 or 3 fuel quantity decreases to approximately 40,200 lbs
In general how would you handle an excessive fuel imbalance situation?
Refer to QRH and Supplementary Procedures, which after determining it’s not a fuel leak, direct you to open and close cross feed valves and turning on and off fuel pumps
In which tank is fuel temperature measured?
Main tank 1
In general how would you handle an excessive fuel imbalance?
Refer to QRH and Supplementary procedures and once it’s determined it’s not a fuel leak, balance by opening and closing cross feed valves in conjunction with turning off and on fuel pumps
Which fuel tanks do reserve tank 1 and 4 transfer to on the 747-8?
Main tanks 1 and 4
On the 747-8, at what fuel quantity will the fuel jettison complete, with the selector in the MLW position?
MLW + 3000Kgs
