Narrative:

Problem began during turn. New captain/first officer on aircraft. Fueling personnel came to cockpit and notified captain of a fueling error. Fueler had put too much fuel in our tank and not enough in the other main. Told fueler to get balance within 1000 pounds and cease fueling operations. Captain left cockpit to supervise/coordinate activities. Fuel was balanced with 8500 pounds in each main as noted during the preflight/originating checklist. Start/taxi and takeoff initiation were normal. Immediately after rotation captain (PF) noted a heavy right wing. Simultaneously, the left main fuel gauge began to wind down to 3000 pounds and the left forward fuel pump low pressure light illuminated, accompanied by the master caution. The captain attempted to balance the fuel load, but despite crossfeed, left main quantity kept failing. The left crossfeed, left main quantity kept falling. The left main gauge stopped decreasing at 14000 pounds. The captain stopped crossfeed, declared an emergency and executed an uneventful flaps 30 approach to runway 4. Fuel load at touchdown was 1400 pounds left and 8500 pounds right main tanks. The 1000 pound limitation of fuel imbalance was exceeded. There was no evidence of fuel leakage upon landing. Maintenance took the aircraft for troubleshooting. They are attempting to solve the mystery. Callback conversation with reporter revealed the following information: the reporter stated, as the first officer, he was busy with the required preflight checks and cockpit setup and the captain was involved with the fueling problem. The reporter said he was not certain the fuel tank drip sticks were pulled to verify the fuel load buy both the left and the right tank underwing and cockpit indicators were at 8500 pounds. The reporter stated after rotation it was obvious the left wing was light and an emergency was declared and diversion executed. The reporter said maintenance has not released any report of component failure or maintenance action taken.

Related reports:

Google
 

Original NASA ASRS Text

Title: A B737-300 IMMEDIATELY AFTER TKOF DECLARED AN EMER AND DIVERTED DUE TO HEAVY RIGHT WING CAUSED BY FUEL UNBALANCE. CAUSED BY INCORRECT FUELING PROCS.

Narrative: PROB BEGAN DURING TURN. NEW CAPT/FO ON ACFT. FUELING PERSONNEL CAME TO COCKPIT AND NOTIFIED CAPT OF A FUELING ERROR. FUELER HAD PUT TOO MUCH FUEL IN OUR TANK AND NOT ENOUGH IN THE OTHER MAIN. TOLD FUELER TO GET BALANCE WITHIN 1000 LBS AND CEASE FUELING OPS. CAPT LEFT COCKPIT TO SUPERVISE/COORDINATE ACTIVITIES. FUEL WAS BALANCED WITH 8500 LBS IN EACH MAIN AS NOTED DURING THE PREFLT/ORIGINATING CHKLIST. START/TAXI AND TKOF INITIATION WERE NORMAL. IMMEDIATELY AFTER ROTATION CAPT (PF) NOTED A HEAVY RIGHT WING. SIMULTANEOUSLY, THE LEFT MAIN FUEL GAUGE BEGAN TO WIND DOWN TO 3000 LBS AND THE LEFT FORWARD FUEL PUMP LOW PRESSURE LIGHT ILLUMINATED, ACCOMPANIED BY THE MASTER CAUTION. THE CAPT ATTEMPTED TO BALANCE THE FUEL LOAD, BUT DESPITE CROSSFEED, LEFT MAIN QUANTITY KEPT FAILING. THE LEFT CROSSFEED, LEFT MAIN QUANTITY KEPT FALLING. THE LEFT MAIN GAUGE STOPPED DECREASING AT 14000 LBS. THE CAPT STOPPED CROSSFEED, DECLARED AN EMER AND EXECUTED AN UNEVENTFUL FLAPS 30 APCH TO RWY 4. FUEL LOAD AT TOUCHDOWN WAS 1400 LBS LEFT AND 8500 LBS RIGHT MAIN TANKS. THE 1000 POUND LIMITATION OF FUEL IMBALANCE WAS EXCEEDED. THERE WAS NO EVIDENCE OF FUEL LEAKAGE UPON LNDG. MAINT TOOK THE ACFT FOR TROUBLESHOOTING. THEY ARE ATTEMPTING TO SOLVE THE MYSTERY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED, AS THE FO, HE WAS BUSY WITH THE REQUIRED PREFLT CHECKS AND COCKPIT SETUP AND THE CAPT WAS INVOLVED WITH THE FUELING PROB. THE RPTR SAID HE WAS NOT CERTAIN THE FUEL TANK DRIP STICKS WERE PULLED TO VERIFY THE FUEL LOAD BUY BOTH THE L AND THE R TANK UNDERWING AND COCKPIT INDICATORS WERE AT 8500 LBS. THE RPTR STATED AFTER ROTATION IT WAS OBVIOUS THE LEFT WING WAS LIGHT AND AN EMER WAS DECLARED AND DIVERSION EXECUTED. THE RPTR SAID MAINT HAS NOT RELEASED ANY RPT OF COMPONENT FAILURE OR MAINT ACTION TAKEN.

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.