Narrative:

Declared emergency due to fuel system failure. At the gate, I reviewed numerous write-ups in aircraft logbook regarding wing fuel imbal. However, fuel was always manageable. Approximately 45 mins after departing lax, our fuel confign caution light was triggered with a 2500 pound wing tank fuel imbal. Center tank empty. We balanced wing fuel via normal procedures, however, this occurred over a much shorter time frame than previous entries in the logbook indicated. I notified dispatch and conferenced our situation with dispatch and aircraft technician over commercial radio. We decided that without further complications, flight would continue to mia. The first officer and I discovered later over elp at FL330 that fuel balance after any kind of turn was required much sooner than expected. At one point, a wing fuel imbal of 1600 pounds occurred in less than 5 mins. With aircraft trimmed autoplt flying indications slight aileron movement banking away from heavy wing. Fuel totalizer indicated that we were within 400 pounds of our scheduled fuel burn. At this point, I was impressed with the rate at which fuel would xfer from wing tank to wing tank in either direction. The first officer and I concluded the fuel xfeed valve stuck open. Wing fuel balance with shallow bank autoplt turns would start fuel siphoning requiring very close monitoring. After another discussion with dispatch we elected to divert the flight to dfw. I briefed the flight attendants then turned off the passenger telephone system. I declared an emergency with ZFW to trigger special handling. We proceeded with fewest turns to 18 mi final to dfw runway 18R. 2 shallow turns for traffic avoidance en route to ickel caused fuel imbals of 600-800 pounds in a very short time 2 mins. Established on 18 mi final wing fuel balanced within 400 pounds landing weight 200-300 pounds. After first officer made normal smooth landing to a full stop, I asked maintenance chief to have aircraft inspected for fuel leaks. Additionally, due to many non english speaking passenger aboard our aircraft accompanied by a flight attendant translator, I was concerned about passenger complete understanding of our situation and their well being, so I asked paramedics to stand by, follow us to our gate. I terminated emergency and debriefed maintenance chief at the gate. Then completed a wrap-up with soc.

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Original NASA ASRS Text

Title: B767 CREW HAD UNCTLED FUEL XFER IN ZFW CLASS A AIRSPACE.

Narrative: DECLARED EMER DUE TO FUEL SYS FAILURE. AT THE GATE, I REVIEWED NUMEROUS WRITE-UPS IN ACFT LOGBOOK REGARDING WING FUEL IMBAL. HOWEVER, FUEL WAS ALWAYS MANAGEABLE. APPROX 45 MINS AFTER DEPARTING LAX, OUR FUEL CONFIGN CAUTION LIGHT WAS TRIGGERED WITH A 2500 LB WING TANK FUEL IMBAL. CTR TANK EMPTY. WE BALANCED WING FUEL VIA NORMAL PROCS, HOWEVER, THIS OCCURRED OVER A MUCH SHORTER TIME FRAME THAN PREVIOUS ENTRIES IN THE LOGBOOK INDICATED. I NOTIFIED DISPATCH AND CONFERENCED OUR SIT WITH DISPATCH AND ACFT TECHNICIAN OVER COMMERCIAL RADIO. WE DECIDED THAT WITHOUT FURTHER COMPLICATIONS, FLT WOULD CONTINUE TO MIA. THE FO AND I DISCOVERED LATER OVER ELP AT FL330 THAT FUEL BAL AFTER ANY KIND OF TURN WAS REQUIRED MUCH SOONER THAN EXPECTED. AT ONE POINT, A WING FUEL IMBAL OF 1600 LBS OCCURRED IN LESS THAN 5 MINS. WITH ACFT TRIMMED AUTOPLT FLYING INDICATIONS SLIGHT AILERON MOVEMENT BANKING AWAY FROM HVY WING. FUEL TOTALIZER INDICATED THAT WE WERE WITHIN 400 LBS OF OUR SCHEDULED FUEL BURN. AT THIS POINT, I WAS IMPRESSED WITH THE RATE AT WHICH FUEL WOULD XFER FROM WING TANK TO WING TANK IN EITHER DIRECTION. THE FO AND I CONCLUDED THE FUEL XFEED VALVE STUCK OPEN. WING FUEL BAL WITH SHALLOW BANK AUTOPLT TURNS WOULD START FUEL SIPHONING REQUIRING VERY CLOSE MONITORING. AFTER ANOTHER DISCUSSION WITH DISPATCH WE ELECTED TO DIVERT THE FLT TO DFW. I BRIEFED THE FLT ATTENDANTS THEN TURNED OFF THE PAX TELEPHONE SYS. I DECLARED AN EMER WITH ZFW TO TRIGGER SPECIAL HANDLING. WE PROCEEDED WITH FEWEST TURNS TO 18 MI FINAL TO DFW RWY 18R. 2 SHALLOW TURNS FOR TFC AVOIDANCE ENRTE TO ICKEL CAUSED FUEL IMBALS OF 600-800 LBS IN A VERY SHORT TIME 2 MINS. ESTABLISHED ON 18 MI FINAL WING FUEL BALANCED WITHIN 400 LBS LNDG WT 200-300 LBS. AFTER FO MADE NORMAL SMOOTH LNDG TO A FULL STOP, I ASKED MAINT CHIEF TO HAVE ACFT INSPECTED FOR FUEL LEAKS. ADDITIONALLY, DUE TO MANY NON ENGLISH SPEAKING PAX ABOARD OUR ACFT ACCOMPANIED BY A FLT ATTENDANT TRANSLATOR, I WAS CONCERNED ABOUT PAX COMPLETE UNDERSTANDING OF OUR SIT AND THEIR WELL BEING, SO I ASKED PARAMEDICS TO STAND BY, FOLLOW US TO OUR GATE. I TERMINATED EMER AND DEBRIEFED MAINT CHIEF AT THE GATE. THEN COMPLETED A WRAP-UP WITH SOC.

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.