Fuel System Flashcards
What are the weights for each fuel tank?
L/R 3050Kg
Center 11300Kg
Total 17400Kg
What do the collector tanks do?
Ensure constant supply of fuel to eng’s/APU. Flapper valves allow fuel into collectors but not out.
What do the surge tanks do?
Collect excess fuel from vent system and return it to respective tank through flapper check valve
Where does each tank vent?
L/C - vent to left surge
R - vents to right surge
Centre has alternate lines that vent right. Float valves stop fuel from entering vent lines when full or in turns
Primary way to move fuel
Motive fuel. High px fuel from engine driven pump creates low pressure flow.
What uses motive fuel?
-tx fuel from C to wing tanks
- tx fuel from wing tanks to collectors
- supply fuel to engines and APU
What are the AC boost pumps used for?
-eng/APU fuel feed backup
- crossfeed
- transfer
Support Eng start in flight
What do the main fuel ejector pumps do?
Primary way to pump fuel to engines from collectors. Uses high px motive flow from EDP. If one or both fail, AC boost pump comes on if in auto.
What are the engine fuel shut off valves controlled by?
L/R eng switched
Where does the APU receive fuel from?
-left eng main fuel ejector
- L/R AC boost pump
- suction if no AC power or left Eng not operating
What do the scavenge ejector pumps do?
Continuously move fuel from the wing tank to the collector. Require motive flow from EDP
How is fuel transferred from Center tank to wing tanks?
Automatically by transfer ejector pumps. When fuel in wing tanks reaches 85.6% of max volume, float valve opens.
How much fuel will the fuel quantity computer allow to be manually transferred?
Wing to wing - 227 kg
Wing to Center - 454 kg
What tanks do gravity transfers connect?
L and R
How does automatic fuel balancing work?
When FQC senses imbalance of more then 180kg between wings, AC boost pump of heavier tank turned on, and both engines fed from heavier tank until within 45kg
Only when Center tank empty
