Fuel Flashcards
Fuel temp indicator gets temp from?
Left main tank
DC fuel pump?
Located in left main wing, used to supply fuel to APU before AC power is established.
Low fuel?
Fuel in either Left or Right main tank drops below 2,200lbsFUEL CONFIG light illuminates &LOW FUEL caution message is displayed.
When are centre tanks inhibited?
Below 50% N2 RPM
L or R FUEL SYS PRESS EICAS message?
Displays when all fuel pumps have low output pressure or all fuel pumps on one side have low output pressure and the cross feed switches are off.
Is there a fuel scavenge system?
Yes it operates automatically when main tanks are approx half empty. Transfers any remaining centre tank fuel to main tanks.
CTR L FUEL PUMP or CTR R FUEL PUMP on EICAS
Several seconds after MSG shows, power is automatically removed from the pump.
When are the L or R FUEL SYS PRESS lights inhibited?
With cross feed valve open
FUEL CONFIG light
Fuel quantity in left and right main tanks differ by more then 2000lbs (+/-500lbs) ORCentre pumps are off with more then 1200lbs in the centre tankALSOConfig light, LOW FUEL caution message and beeper sounds when fuel quantity is less then 2200lbs in either main tank.
What fuel pumps operate the APU
DC pump automatically on ground with no AC power.FORWARD LEFT AC PUMP AFTER AC POWER SUPPLIED
How many fuel pumps are fitted per tank and what is there power source?
Each tank contains- 2 AC driven fuel pumps.Left main tank also has a DC driven fuel pump for APU feed.
Is engine operation still possible without the fuel pumps turned on?
Yes. When main tank fuel press is low, each engine can draw fuel through its corresponding tank through a suction feed line that bypasses the pumps. However at high altitude thrust editorial ion or engine flame out may occur as a result of the fuel flow reduction.
What Isnthe purpose of the NGS?
Converts bleed air to nitrogen enriched air at all phases of flight. Nitrogen enriched air is then delivered to the centre tank to reduce flammability in the tank.