Narrative:

Aircraft was preflted normally. Fuel caps noted to be in the flush, closed position. During rotation fuel was noticed leaking from the right inboard fuel tank. Return to landing runway and normal landing was completed. Further investigation revealed that cap can come loose if it is put on when in the closed position, aligning marks must line up. Line departments and pilots should be made aware of this.

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Original NASA ASRS Text

Title: BE100 ATX ACFT FUEL CAP APPEARED TO BE FLUSH AND CLOSED, BUT AFTER AIRBORNE FUEL WAS SEEN LEAKING FROM CAP. RPTR RETURNED, LANDED, SECURED CAP AND CONTINUED.

Narrative: ACFT WAS PREFLTED NORMALLY. FUEL CAPS NOTED TO BE IN THE FLUSH, CLOSED POS. DURING ROTATION FUEL WAS NOTICED LEAKING FROM THE R INBOARD FUEL TANK. RETURN TO LNDG RWY AND NORMAL LNDG WAS COMPLETED. FURTHER INVESTIGATION REVEALED THAT CAP CAN COME LOOSE IF IT IS PUT ON WHEN IN THE CLOSED POS, ALIGNING MARKS MUST LINE UP. LINE DEPTS AND PLTS SHOULD BE MADE AWARE OF THIS.

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.