Narrative:

Uneventful ground fueling at sna. I noticed an error on the residual fuel quantity from the previous flight on the fuel slip. I then looked in the aircraft logbooks to compare and found the fueler had erred. The fuel delivered and residual fuel (from the aircraft logbook) added up correctly to the required release fuel. Fuel gauges in the cockpit also confirmed this. Takeoff/departure and climb to cruise uneventful except for random vectors issued for traffic avoidance. At top of climb compared fuel burn to predicted burn on flight plan, found 1000 pound discrepancy then reconfirmed all fuel figures, wind, etc. No errors evident. Continued to monitor fuel status. Plenty of fuel on board to msp. Approximately at den monitored fuel and found discrepancy increasing. Inspected aircraft, found no apparent leaks/streaming. Communicated with company, intent to continue to final destination of msp. Fuel leak unconfirmed but rate of discrepancy increasing 100-200 pounds every 100 NM. Assigned holding by ZMP at sketr intersection. Contacted company, unable to hold when losing fuel though had well above emergency fuel. Company could not help with route holding. Captain and I discussed situation and did not want to hold with fuel leak for 30 mins or more. Hence, declared an emergency and told center it was a fuel leak. We did not hold and were sequenced in for the approach. When approach came on the frequency, they weren't informed of the emergency or status. We updated them and continued on the approach. We also informed approach no emergency vehicles were needed. Approach and landing uneventful. Emergency vehicles in place escorting to gate area. Final fuel discrepancy approximately 2000 pounds. Maintenance called for action. Additionally throughout flight, both of us monitored all possible divert airfields if the fuel loss increased rapidly to ensure we had a plan and a safe landing could be made. Callback conversation with reporter revealed the following information: reporter always does a fuel xchk using fuel quantity versus fuel flow, fuel used. He normally finds correlation to within several hundred pounds. They began to suspect a fuel leak when the total fuel was being used faster than the fuel consumed. The company maintenance control was notified, and they in turn notified the flight office. On arrival, the area behind the fueling filler receptacle connections was found wet with fuel. Before further investigation could be conducted the fueler had begun fueling for the next flight. This upset the check valves in the fueling receptacles. After fueling, no further fuel leaks were evident. The same crew flew the aircraft on the next leg and found no unaccounted fuel loss.

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Original NASA ASRS Text

Title: A320 CREW HAD FUEL LEAK ENRTE TO MSP.

Narrative: UNEVENTFUL GND FUELING AT SNA. I NOTICED AN ERROR ON THE RESIDUAL FUEL QUANTITY FROM THE PREVIOUS FLT ON THE FUEL SLIP. I THEN LOOKED IN THE ACFT LOGBOOKS TO COMPARE AND FOUND THE FUELER HAD ERRED. THE FUEL DELIVERED AND RESIDUAL FUEL (FROM THE ACFT LOGBOOK) ADDED UP CORRECTLY TO THE REQUIRED RELEASE FUEL. FUEL GAUGES IN THE COCKPIT ALSO CONFIRMED THIS. TKOF/DEP AND CLB TO CRUISE UNEVENTFUL EXCEPT FOR RANDOM VECTORS ISSUED FOR TFC AVOIDANCE. AT TOP OF CLB COMPARED FUEL BURN TO PREDICTED BURN ON FLT PLAN, FOUND 1000 LB DISCREPANCY THEN RECONFIRMED ALL FUEL FIGURES, WIND, ETC. NO ERRORS EVIDENT. CONTINUED TO MONITOR FUEL STATUS. PLENTY OF FUEL ON BOARD TO MSP. APPROX AT DEN MONITORED FUEL AND FOUND DISCREPANCY INCREASING. INSPECTED ACFT, FOUND NO APPARENT LEAKS/STREAMING. COMMUNICATED WITH COMPANY, INTENT TO CONTINUE TO FINAL DEST OF MSP. FUEL LEAK UNCONFIRMED BUT RATE OF DISCREPANCY INCREASING 100-200 LBS EVERY 100 NM. ASSIGNED HOLDING BY ZMP AT SKETR INTXN. CONTACTED COMPANY, UNABLE TO HOLD WHEN LOSING FUEL THOUGH HAD WELL ABOVE EMER FUEL. COMPANY COULD NOT HELP WITH ROUTE HOLDING. CAPT AND I DISCUSSED SIT AND DID NOT WANT TO HOLD WITH FUEL LEAK FOR 30 MINS OR MORE. HENCE, DECLARED AN EMER AND TOLD CTR IT WAS A FUEL LEAK. WE DID NOT HOLD AND WERE SEQUENCED IN FOR THE APCH. WHEN APCH CAME ON THE FREQ, THEY WEREN'T INFORMED OF THE EMER OR STATUS. WE UPDATED THEM AND CONTINUED ON THE APCH. WE ALSO INFORMED APCH NO EMER VEHICLES WERE NEEDED. APCH AND LNDG UNEVENTFUL. EMER VEHICLES IN PLACE ESCORTING TO GATE AREA. FINAL FUEL DISCREPANCY APPROX 2000 LBS. MAINT CALLED FOR ACTION. ADDITIONALLY THROUGHOUT FLT, BOTH OF US MONITORED ALL POSSIBLE DIVERT AIRFIELDS IF THE FUEL LOSS INCREASED RAPIDLY TO ENSURE WE HAD A PLAN AND A SAFE LNDG COULD BE MADE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR ALWAYS DOES A FUEL XCHK USING FUEL QUANTITY VERSUS FUEL FLOW, FUEL USED. HE NORMALLY FINDS CORRELATION TO WITHIN SEVERAL HUNDRED LBS. THEY BEGAN TO SUSPECT A FUEL LEAK WHEN THE TOTAL FUEL WAS BEING USED FASTER THAN THE FUEL CONSUMED. THE COMPANY MAINT CTL WAS NOTIFIED, AND THEY IN TURN NOTIFIED THE FLT OFFICE. ON ARR, THE AREA BEHIND THE FUELING FILLER RECEPTACLE CONNECTIONS WAS FOUND WET WITH FUEL. BEFORE FURTHER INVESTIGATION COULD BE CONDUCTED THE FUELER HAD BEGUN FUELING FOR THE NEXT FLT. THIS UPSET THE CHK VALVES IN THE FUELING RECEPTACLES. AFTER FUELING, NO FURTHER FUEL LEAKS WERE EVIDENT. THE SAME CREW FLEW THE ACFT ON THE NEXT LEG AND FOUND NO UNACCOUNTED FUEL LOSS.

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.