Narrative:

Performed normal takeoff in light transport. Upon rotation, tower advised that we were leaking fuel. Captain observed fuel leaking from left tip tank fuel cap. The captain considered holding long enough to burn enough fuel to be at maximum gross landing weight. However, since fuel was leaking from the left tip tank and the light transport does not have fuel dump capability, there existed a serious lateral imbalance problem. The potential existed that we could have had a situation where the left tip tank was near empty with the right tip tank near full. This situation may have made the aircraft uncontrollable on landing. The decision was made that landing over gross landing weight presented the least safety hazard. The landing was made successfully. The fueler and second in command had checked the fuel cap for security prior to taxi. A mechanic had inspected the fuel cap after we landed and noted that the tension was loose and was the probable cause of the fuel leak. He made an adjustment and no further leaks occurred.

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Original NASA ASRS Text

Title: LTT INFORMED FUEL LEAKING AT TKOF. RETURNS TO LAND, BUT IS OVERWT.

Narrative: PERFORMED NORMAL TKOF IN LTT. UPON ROTATION, TWR ADVISED THAT WE WERE LEAKING FUEL. CAPT OBSERVED FUEL LEAKING FROM LEFT TIP TANK FUEL CAP. THE CAPT CONSIDERED HOLDING LONG ENOUGH TO BURN ENOUGH FUEL TO BE AT MAX GROSS LNDG WT. HOWEVER, SINCE FUEL WAS LEAKING FROM THE L TIP TANK AND THE LTT DOES NOT HAVE FUEL DUMP CAPABILITY, THERE EXISTED A SERIOUS LATERAL IMBALANCE PROBLEM. THE POTENTIAL EXISTED THAT WE COULD HAVE HAD A SITUATION WHERE THE L TIP TANK WAS NEAR EMPTY WITH THE R TIP TANK NEAR FULL. THIS SITUATION MAY HAVE MADE THE ACFT UNCTLABLE ON LNDG. THE DECISION WAS MADE THAT LNDG OVER GROSS LNDG WT PRESENTED THE LEAST SAFETY HAZARD. THE LNDG WAS MADE SUCCESSFULLY. THE FUELER AND SECOND IN COMMAND HAD CHKED THE FUEL CAP FOR SECURITY PRIOR TO TAXI. A MECH HAD INSPECTED THE FUEL CAP AFTER WE LANDED AND NOTED THAT THE TENSION WAS LOOSE AND WAS THE PROBABLE CAUSE OF THE FUEL LEAK. HE MADE AN ADJUSTMENT AND NO FURTHER LEAKS OCCURRED.

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.