Here is the Airbus A330 procedure for FUEL IMBALANCE and for FUEL LEAK. (current as of May 2003)
FUEL IMBALANCE
FOB......................................................... ...............................................CHECK
Compare the FOB+FU with the FOB at departure. If the difference is significant, or if the FOB+FU decreases, suspect a fuel leak.
CAUTION
A fuel imbalance may indicate a fuel leak.
Do not apply this procedure, if a fuel leak is suspected. Refer to FUEL
LEAK procedure
– WING X FEED............................................ON
If the WING X FEED valve is open :
On the lighter side :
– (ALL) FUEL PUMPS (STBY then NORM)..................................OFF
When fuel balanced :
– PUMPS (NORM then STBY)...................................................ON
– WING X FEED ............................................................ ...... AUTO
If the WING X FEED valve is failed closed :
– OUTER TK XFR......................................................... .........ON
– BANK ANGLE ...............................3 DEG WING DOWN ON LIGHTER SIDE
Fuel transfer only occurs if the bank angle is at, or above, 2 to 3 degrees. Modulate
the fuel imbalance through the bank angle.
– RUDDER TRIM........................................................ .................USE
– Use rudder trim to get constant course and neutral stick.
Fuel Leak
A fuel leak may either be detected, if :
•
The sum of FOB and FU is significantly less than FOB at engine start, or is decreasing, or
•
A passenger observes a fuel spray from an engine/pylon or wing tip, or
•
The total fuel quantity is decreasing at an abnormal rate, or
•
A fuel imbalance is developing, or
•
Fuel quantity in a tank is decreasing too fast (leak from engine/pylon, or hole in a tank), or
•
A tank is overflowing (due to a pipe rupture in a tank), or
•
The Fuel flow is excessive (leak from engine), or
•
Fuel is smelt in the cabin.
If visibility permits, leak source may be identified by a visual check from the cabin.
LAND ASAP
LEAK FROM ENGINE/PYLON CONFIRMED :
Engine fuel leak can be confirmed by excessive fuel flow indication, or a visual check.
– THR LEVER (of affected engine) ........................................... IDLE
– ENG MASTER (of affected engine) ........................................ OFF
– FUEL X FEED ...........................................................U SE AS RQRD
If the leak stops, the crossfeed valves can now be opened to re-balance fuel quantity, or to enable use of fuel from both wings. Do not restart the engine.
LEAK FROM ENGINE/PYLON NOT CONFIRMED or LEAK NOT LOCATED
Stop any fuel transfer, and then monitor the depletion rate of each inner tank, to determine if the leak is from an engine or a wing (case 1), or from the Trim tank, or the APU/Trim feeding lines (case 2).
– FUEL X FEED ...................................................MAINTAIN CLOSED
The crossfeed valves must remain closed to prevent the leak from affecting both sides.
– T TANK FEED........................................................ ............. ISOL
– INNER TANKS FUEL QUANTITIES .................................. MONITOR
Monitor the depletion rate of each inner tank.
WHEN A LEAK IS CONFIRMED
CASE 1: IF ONE INNER TANK DEPLETES FASTER THAN THE OTHER
BY AT LEAST 500 KG (1100 LB) IN LESS THAN 30 MINS :
An engine leak may still be suspected. Therefore :
– THR LEVER (engine on leaking side)...................................... IDLE
– ENG MASTER (engine on leaking side).................................... OFF
– FUEL LEAK ............................................................ .... MONITOR
If leak stops :
If the inner tank fuel quantity of the affected side stops decreasing, the
engine leak is confirmed and stopped.
– T TANK FEED........................................................ ....... AUTO
– FUEL X FEED..................................................... USE AS REQRD
The crossfeed valves can now be opened to re-balance fuel quantity, or
to enable use of fuel from both wings. Do not restart the engine.
If leak continues (after engine shutdown) :
If the inner tank fuel quantity of the affected side continues to decrease, a leak from a wing may be suspected..
– ENGINE RESTART ..................................................... CONSIDER
– FUEL LOSS REDUCTION proc ...................................... CONSIDER
CASE 2: IF BOTH INNER TANKS DEPLETE AT A SIMILAR RATE :
A leak from the Trim tank, or the APU/Trim feeding lines may be suspected :
If fuel smell in the cabin :
– APU (if ON)......................................................... ............... OFF
– T TANK FEED........................................................ .MAINTAIN ISOL
This prevents additional fuel loss through the APU/Trim feeding lines.
If no fuel smell in the cabin :
A leak from the Trim tank may be suspected :
– FUEL LOSS REDUCTION proc .............................. CONSIDER
CAUTION
Do not apply the FUEL IMBALANCE procedure. Approach and landing can be one, even with one full wing/one empty wing.
FOR LANDING
CAUTION
Notify ATC and do not use reverse.
best regards,
Bruce Waddington
apologies for the formating