Fuel Flashcards
Briefly explain the centre tank logic.
Centre tanks don’t start pumping until 500kg fuel is burnt.
On the CEO, they won’t feed until slats are retracted too incase of fuel contamination as both engines can be fed by the same fuel.
How is the IDG cooled and where is the returning fuel fed to?
Fuel taken from inner tank (high-pressure fuel line in that engine), goes through the the IDG cooler to warm the fuel and cool the IDG, then fuel fed back to the outer tank
In a CEO, when approximately does the outer tank start to feed the inner tank?
The transfer valves automatically open when the inner tank fuel reaches the low level 750kg, thus enabling the fuel to drain from the outer to the inner tanks.
When might you expect to see the low level fuel ECAM?
750kg
What is a jet pump and why do you think they have an advantage over the conventional centre pump configuration?
They’re essentially transfer valves rather than pumps.
They use pressure in the inner tanks to transfer fuel (sucks fuel) from the centre tanks to the inner tanks via a Venturi like transfer valve.
As they transfer fuel to the inner tanks, they are not feeding the engines directly so there is no slats logic like with centre tank pumps.
Lighter, simpler, less maintenance, less likely to break
With regards to the fuel leak, what indications in the flight deck may help you locating a leak from an engine or pylon?
Excessive fuel flow, low N1
When operating in colder climates, you may see fuel tank low temp caution. What might you consider operationally to help increase the temperature of the fuel back into the normal operating range?
Descending
In which order is the fuel burnt from each tank and why?
Centre tank, inner tanks until 750kg and then the outer.
Less stress on the wings (wing bending logic)
Minimum fuel temperature?
Alert triggers at -43 degrees
