FUEL SYSTEM Flashcards
What is the Total Fuel capacity?
18 729 kg
What is the capacity of the Center Fuel Tank?
6 476 kg
What is the Wing Fuel Tank capacity?
5 435 kg x 2
What would happen if both the inner fuel tank pumps fails?
Suction valves allows the inner tanks to gravity feed to the engine
Can gravity feeding of fuel be done from the Center Tank?
No
What does it mean if the Fuel Quantity in the Outer Tank is boxed in amber?
The transfer valves have failed in the closed position
When will the fuel quantity for the wing tanks pulse?
When the difference between fuel quantities in the wing tanks is greater than 1500 kg, the higher value pulses
What does it mean when the ECAM FOB indication has a half amber box around it?
Displayed qty is not all useable
What does the REFUELG memo message mean?
The refueling panel door is open, it doesn’t necessarily mean that refueling is taking place
What does a fault light on the CTR TK MODE SEL pb mean?
Center tank has more than 250 kg and either wing tank have less than 5 000 kg
What does a FAULT light on a Fuel Pump pb mean?
Low Fuel Pressure
How long does it take to refuel?
17 min to fill the wings and about 20 to fill all the tanks
When refueling, what tanks fill first and why?
Wing tanks fill up first and then spill inboard to maintain balance
When does the Center Tank fill up during refueling?
If the selected fuel load exceeds the wing tank capacity, the center tank is simultaneously filled up
When will the fuel system transfer valves automatically close?
During the next re-fueling operation
How are the IDG:s cooled?
Some of the fuel supplied to each engine is tapped off from the HP fuel line and routed through the IDG heat exchanger. It then goes through a return valve to the wing tank.
What is indicated on the SD, by a Center Tank fuel pump indication of cross-line (green)?
Pump contactor is off, and auto shut-off is required
What is indicated on the SD, by a Center Tank fuel pump indication of cross-line (amber)?
Pump contactor is off, and auto shut-off is not required
Can the wing tanks gravity feed?
Yes
What does amber lines through the last two digits on the fuel indication mean?
The FQI are downgraded or inaccurate
When does the “fuel used” indication reset to zero?
It’s automatically reset when the engine is started on the ground
What causes a fuel tank temperature indication to go amber?
- Wing tank temperature is > 45 deg
Any tanks temperature is below -40 deg C
What does a “corner” amber box around the FOB mean?
Indicates that fuel onboard is trapped. Meaning that transfer valve has failed or loss of center tank pumps
What does FUEL X FEED message mean?
The FUEL X FEED pb is pushed
How does the APU fuel feed work?
A special pump supplies fuel for the APU start up when fuel feed pressure is low (due to loss of tank pumps or loss of AC electrical supply).
This pump normally runs off the AC ESS SHED bus, powered by the Batteries and the static inverters. Can run off the AC STAT INV BUS if the AC ESS SHED fails
Where is the re-fueling point?
The standard point is under the right wing
What is the purpose of the cross feed valve?
It allows both engines to be fed from one wing tank to balance fuel load, or one engine to be fed from both sides to utilize all the fuel in a single engine situation
After engine shutdown, what are your actions to close the fuel transfer valves?
No action required. The valves will close automatically during the next re-fueling
How many fuel pumps are installed?
7
2 in each wing tank
2 in the center tank
1 APU pump
When does the APU fuel pump run?
When the wing or center tank pumps are not ON
What does a FAULT light in the FUEL PUMP pb indicate?
Low fuel delivery pressure
Can fuel be transferred from one tank to another?
Only during ground refueling
Why are the wing tanks drained last?
Structural bending relief
What is the purpose of the MODE SEL pb on the fuel panel?
The Center tank transfer valves operates when the pb is pressed and electrical power is available
Is the APU fuel pump AC or DC driven?
Normally AC, but it can be used from a DC source via a static inverter. So it can be started off battery power
Are the fuel pumps in the tanks LO or HI pressure pumps?
LO Pressure
What is the IGGS in the fuel system?
Inert Gas Generation System
Works like the NGS system on Boeing aircrafts.
As fuel is being used nitrogen rich air is introduced into the tank to avoid sparking a fire. Air with less than 12% oxygen is considered not flammable
What is the FLSCU in regards to the fuel system?
Fuel Level Sensing Control Unit
Which of the fuel tanks have the “NGS” system?
Why not have the NGS system in the wing tanks?
Only the Center Tank
Flash point of fuel is 38 deg C. Normally the Center Tank fuel will be below that temperature, but because the packs are located below the tanks the fuel can heat up above 38 deg C. This problem does not exist for the wing tanks
How does the Nitrogen Generation system work?
It takes bleed air and first cools it, then it goes through a separator that separates Nitrogen and Oxygen. Oxygen is vented overboard and the Nitrogen is fed into the Center Tank to keep the Nitrogen level at around 88%. This means that Oxygen is around 12%, which is not high enough to sustain combustion.
What is the fuel imbalance allowed after refueling?
0-6 tons = 400 kg
6-12 tons = 500 kg
12- up = 600 kg
When is a LO LVL warning triggered?
If any wing tank is below 750 kg
Where does the IDG cooling fuel return to?
The wing tanks
What functions are provided by the FLSCS?
- Automatic control of the transfer valves
- Controls de-fueling
- IDG cooling re-circulation
How is fuel transferred from the center tank to the wing tanks?
When the transfer valve is open, fuel from the wing tank pumps flows through the jet pump and creates suction that moves fuel from the center tank to the wing tank
What happens with the transfer valves when a wing tank is full?
FLSCS closes the transfer valve and re-opens when 250kg is used from the wing tank
What functions are provided by the FQIS?
Transmitts fuel qty, temp and mass to ECAM
it also controls automatic re-fueling
What closes the LP fuel valves?
ENG MASTER SWITCH to off or
ENG FIRE PUSH pb
How can engines be gravity fed?
Suction valves are closed by pump pressure in normal operation. When a pump fails the automatically open
