Narrative:

During climb after departing lax, ECAM-indicating 'fuel automatic-feeding fault' annunciated. Followed by 'fuel imbalance' from malfunction fuel feed system. Diverted to nearest suitable field after declaring in-flight emergency. Uneventful overweight landing accomplished. Cause unknown at this time. Callback conversation with reporter revealed the following information: the first officer said that the control valve involved in the metering of the fuel was of a faulty material. When the material deteriorates the valve does not assume the correct position for a balanced fuel feed. In this case, all of the fuel for both engines was coming from the left main tank. In this case the crew went to manual xfeed. The xfeed did not work, so the crew turned off the left boost pumps, leaving the right ones on. That did not change the feed from the left main tank. Flight diverted to ZZZ. On final approach at 500 ft AGL the crew received a 'right wing tank venting overboard' warning. Once on the runway they turned off all boost pumps with the crash fire rescue equipment vehicles watching the aircraft. On landing they had 4000 pounds in the left tank and 15000 pounds in the right tank with approximately 26000 pounds in the center tank. The air carrier safety department said that there was no danger of the engines failing from fuel starvation when the left tank ran dry as the other tanks would have taken over. Airbus knows of this problem and any day now is coming out with temporary procedure for an in-flight fix while looking for a new manufacturer for the valve.

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Original NASA ASRS Text

Title: AFTER DEP LAX, AN A321 EXPERIENCES A FUEL IMBALANCE WARNING ON THE ECAM SYS. CREW DIVERTS FOR EMER LNDG AT ZZZ.

Narrative: DURING CLB AFTER DEPARTING LAX, ECAM-INDICATING 'FUEL AUTO-FEEDING FAULT' ANNUNCIATED. FOLLOWED BY 'FUEL IMBALANCE' FROM MALFUNCTION FUEL FEED SYS. DIVERTED TO NEAREST SUITABLE FIELD AFTER DECLARING INFLT EMER. UNEVENTFUL OVERWT LNDG ACCOMPLISHED. CAUSE UNKNOWN AT THIS TIME. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE FO SAID THAT THE CTL VALVE INVOLVED IN THE METERING OF THE FUEL WAS OF A FAULTY MATERIAL. WHEN THE MATERIAL DETERIORATES THE VALVE DOES NOT ASSUME THE CORRECT POS FOR A BALANCED FUEL FEED. IN THIS CASE, ALL OF THE FUEL FOR BOTH ENGS WAS COMING FROM THE L MAIN TANK. IN THIS CASE THE CREW WENT TO MANUAL XFEED. THE XFEED DID NOT WORK, SO THE CREW TURNED OFF THE L BOOST PUMPS, LEAVING THE R ONES ON. THAT DID NOT CHANGE THE FEED FROM THE L MAIN TANK. FLT DIVERTED TO ZZZ. ON FINAL APCH AT 500 FT AGL THE CREW RECEIVED A 'R WING TANK VENTING OVERBOARD' WARNING. ONCE ON THE RWY THEY TURNED OFF ALL BOOST PUMPS WITH THE CFR VEHICLES WATCHING THE ACFT. ON LNDG THEY HAD 4000 LBS IN THE L TANK AND 15000 LBS IN THE R TANK WITH APPROX 26000 LBS IN THE CTR TANK. THE ACR SAFETY DEPT SAID THAT THERE WAS NO DANGER OF THE ENGS FAILING FROM FUEL STARVATION WHEN THE L TANK RAN DRY AS THE OTHER TANKS WOULD HAVE TAKEN OVER. AIRBUS KNOWS OF THIS PROB AND ANY DAY NOW IS COMING OUT WITH TEMPORARY PROC FOR AN INFLT FIX WHILE LOOKING FOR A NEW MANUFACTURER FOR THE VALVE.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.