FCOM - Fuel

Question 1

The are two feeder tanks. One per tank. What are their capacity?

Answer 1

200 ltrs. equal to approximately 160 kg.

Question 2

In normal operation engine running the jet pump supplies the engine with fuel. What happens if it doesn’t work?

Answer 2

If jet pump pressure drops below 5 psi. the low pressure electrical fuel pump automatically starts. This pump is able to supply one engine in the entire flight envelope.

Question 3

Name functions of the electrical pump.

Answer 3

In normal operation it only helps to start the engine. It also starts in non normal situations as follows:

• Jet pump pressure drops below 5 psi.
• Low level in a tank. Below 200 ltrs./160 kg.
• When crossfeeding fuel.

Question 4

In case the fuel crossfeed label flashes what does that indicate?

Answer 4

Abnormal crossfeed valve operation meaning trying to either crossfeed with both electrical fuel pumps OFF, both electrical fuel pumps ON or having the electrical fuel pump on on the side where the amount of fuel is lowest.

Question 5

On ground with battery OFF is it possible to fuel the aircraft?

Answer 5

Yes, through the Ground Handling Bus when the refuel door is open. In case the Ground Handling Bus CB is pulled the aircraft can not be refuelled.

Question 6

How can You detect a jet pump failure?

Answer 6

RUN light comes on during normal operation indicating that the electrical pump has started because of jet pump pressure below 5 psi.

Question 7

FUEL MISMATCH comes on when?

Answer 7

Difference more that 200 kg. between fuel quantity calculated by the FMS and FCU respectively. The difference has to be present 10 sec. on ground and 60 sec. in flight to be triggered.

Question 8

FUEL UNBALANCED comes on when?

Answer 8

Discrepancy of more than 100 kg. between left and right tank.