View Full Version : Total Fuel Pump Failure on A330/340
knarfo
16th Aug 2018, 07:36
Hi Folks,
here is a theoretical question. Let us assume, all fuel pumps fail inflight. What happens to the engines? I remember from my Boeing days, that engine operation is always assured. Any ideas for Airbus?
Cheers and looking for your comments
Goldenrivett
16th Aug 2018, 07:56
With engines slung below the wings, why do you think Airbus would behave differently to Boeing during Gravity Fuel Feeding?
gearlever
16th Aug 2018, 08:17
With engines slung below the wings, why do you think Airbus would behave differently to Boeing during Gravity Fuel Feeding?
Hhm, maybe wires not pipes:*
A and C
16th Aug 2018, 08:20
In both cases fuel flow is assured up to about FL240, this is because the fuel tanks are pressurised by airflow from the NACA ducts below the wings ( via the vent surge tanks ).
With engines slung below the wings, why do you think Airbus would behave differently to Boeing during Gravity Fuel Feeding?
Gravity might work in a C150.. 737s have a suction feed
FCOM 12.20.2 "When main tank fuel pump pressure is low, each engine can draw fuel from its corresponding main tank through a suction feed line that bypasses the pumps."
Hi Folks,
here is a theoretical question. Let us assume, all fuel pumps fail inflight. What happens to the engines? I remember from my Boeing days, that engine operation is always assured. Any ideas for Airbus?
Cheers and looking for your comments
Since this is a totally theatrical question, apparently if one were to forget to turn any of the main or standby fuel pumps on all of the engines will still start and run ;)
divinehover
16th Aug 2018, 15:33
Since this is a totally theatrical question, apparently if one were to forget to turn any of the main or standby fuel pumps on all of the engines will still start and run ;)
Saw that happen in a B727 when the Flight Eng forgot to switch on the fuel pumps before start. Engines started fine
gearlever
16th Aug 2018, 15:36
Saw that happen in a B727 when the Flight Eng forgot to switch on the fuel pumps before start. Engines started fine
Ooops, 8 amber lights...:hmm:
PA38-Pilot
16th Aug 2018, 16:05
Since this is a totally theatrical question, apparently if one were to forget to turn any of the main or standby fuel pumps on all of the engines will still start and run ;)
They start just fine on the A320 too. Don't ask me how I know :O
vilas
16th Aug 2018, 16:51
On A320 they have started both engines with all fuel pumps off putting off all warnings without checking and then climbed to FL380 experienced dual engine flame out realized their blunder, managed to relight both and landed back. Human propensity for screw up is unlimited.
tdracer
16th Aug 2018, 20:09
IF the fuel is "weathered" - that is it's been at altitude for an hour or more so that the dissolved gasses have boiled out of the fuel - suction feed usually works pretty well and should keep the engines running above 30k.
However, if the fuel isn't weathered the engine driven fuel pumps will cavitate at altitude - engine operation will come erratic - flameout or a surge/stall is likely. Plus the cavitation can cause damage to the fuel pumps - reducing the pumping capability and generating debris into the engine fuel system.
There have been several cases where shortly after reaching cruise altitude, crew members turned off the wing boost pumps instead of the center wing tank pumps, resulting in an all engine power loss. Fortunately, best as I can remember, they were always able to restart the engines.
Pearly White
17th Aug 2018, 07:15
IF the fuel is "weathered" - that is it's been at altitude for an hour or more so that the dissolved gasses have boiled out of the fuel - suction feed usually works pretty well and should keep the engines running above 30k.
However, if the fuel isn't weathered the engine driven fuel pumps will cavitate at altitude - engine operation will come erratic - flameout or a surge/stall is likely. Plus the cavitation can cause damage to the fuel pumps - reducing the pumping capability and generating debris into the engine fuel system.
There have been several cases where shortly after reaching cruise altitude, crew members turned off the wing boost pumps instead of the center wing tank pumps, resulting in an all engine power loss. Fortunately, best as I can remember, they were always able to restart the engines.
I bet they blamed it on the nearest volcano.