This Topic is relevant to the whole fleet

GENERAL

The main fuel pump system supplies fuel from the inner wing tanks to the engines. The system has four main fuel pumps and two standby fuel pumps.

The Fuel Control and Monitoring System (FCMS) automatically controls the fuel distribution.

The collector box in each inner tank supplies fuel to its associated engine, but can also supply the other engine if necessary through a cross-feed system. There are two fuel pumps in each collector. A standby pump is fitted directly in the inner tank.

MAIN COMPONENTS

INNER TANK PUMPS

Usually only the main fuel pumps operate and the closed cross-feed valve divides the system into two parts, one part for each engine. It is possible (with the cross-feed valve open) for one fuel pump to supply sufficient fuel to both engines. Each standby fuel pump automatically operates if there is a failure of one of its related main fuel pumps or if one or both related main pump(s) is (are) switched off.





CROSS FEED VALVE

A cross feed valve controlled by a double motor allows both engines to be fed from one side or one engine to be fed from both sides.

The cross feed valve opens automatically in electrical emergency configuration.





ENGINE LP VALVE

The fuel flow to an engine can be stopped by its low pressure (LP) fuel valve.

The closure of the LP fuel valve is controlled by :

	the engine master switch, or
	the ENG FIRE PUSH pushbutton.

FOR INFO




ENGINE FEED




 

FUEL FEED SEQUENCE

NORMAL OPERATION

Fuel is always fed to the engines from inner tanks. The tanks empty in the following sequence:

1. inner tanks (down to 4000 kg (5000 kg *) in each inner tank)

2. trim tank (fuel transferred into the inner tanks)

3. outer tanks (fuel transferred into the inner tanks)


Note : 

1. Trim tank may be emptied earlier if required for CG control.

2. For transfer from trim tank to inner tank refer to CG control.

Outer to inner tanks transfer

Automatic transfer of fuel from the outer tanks is performed by gravity.

It occurs when the trim tank has been emptied and either inner tank reaches 3500 kg (4000 kg*).

Outer tank fuel transfer valves are used to cycle the inner tanks contents between 3500 kg (4000 kg*) and 4000 kg (4500 kg*). These valves are closed when outer tanks are empty for 5 minutes.

* If the trim tank forward transfer pump fails.

ECAM indication

Manual outer to inner tanks transfer

The flight crew can select manually the transfer from outer to inner tanks through the OUTR TK XFR pushbutton.

When selected ON, the outer tanks fuel transfer and the inner and outer inlet valves are controlled open.

FUEL FEED WITH BOTH ENGINES OUT

EMER GEN powered by the RAT :

The X-FEED valve is automatically opened.

Only the normal LEFT PUMP 2 is powered.

If the normal LEFT PUMP 2 fails or is selected OFF, the RIGHT PUMP 2 replaces it automatically.

When the speed decreases below 260 knots or, when LAND RECOVERY is selected ON, (whichever occurs first), all pumps are lost. The FWD APU pump starts automatically irrespective of the APU master switch position to start any engine.

Flight on batteries :

All normal and STBY pumps are lost.

The FWD APU pumps starts automatically irrespective of the APU master switch position to start any engine.