Fuel System Flashcards
How is the fuel moved from the center tank to the main tanks
transfer ejectors
How is the fuel moved from the main tanks to the collector tanks
Scavenge ejectors and gravity
How is the fuel moved from the collector tanks to the engine driven high pressure fuel pump
Main ejectors
backed up by DC electric boost pumps
What is the function of the electric boost pumps
To provide initial fuel for engine start and to back-up the main ejectors when ejector pressure is low
Will an engine continue to run with a failed engine driven fuel pump?
No
What is the maximum fuel imbalance
300 lbs for takeoff,
800 lbs for all other phases
When will the fuel system automatically begin transferring fuel
200 lb fuel imbalance
When are the boost pumps automatically energized
Low pressure from the main ejectors
if the pumps are armed
Where is the high pressure fuel pump located
N2 accessory gearbox
Where is bulk fuel temperature taken
right main tank
What is the Minimum Bulk Fuel Temp for take-off (Jet A)
-30°C
What is the minimum bulk fuel temp during flight (Jet A)
above -40°C
How is engine fuel heated
Fuel/oil heat exchanger
What is the minimum engine fuel temperature for takeoff
+5°C
What is the takeoff limitation if the center tank has > 500 lbs of fuel
Each main (wing) tank must have more than 4400 lbs
