Narrative:

On apr/xa/06; I was acting as PIC on a commercial cross country with my instructor. The flight was from mer-bfl. At bfl I refueled the aircraft and we began our return flight to mer. En route; we received a low fuel indication on our right tank; and diverted to the closest airport; fat. Whilst sitting in the FBO we were informed that the left fuel cap was missing. As PIC I decided to ground the airplane and return to mer from fat by taxi. With the fuel cap missing; my instructor advised me to call bfl and inform them that we were missing a fuel cap. My instructor's first thoughts were that 'he hoped it was not on the runway at bfl; and actions were taken to advise them to do a runway sweep.' I am certain that the fuel cap must have become loose in-flight. This is because I make it a habit to always doublechk my fuel caps after I refuel; or after an FBO fuels my airplane; my instructor always enforces that I do this.

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Original NASA ASRS Text

Title: SYMPHONY 160 FLT CREW HAS A LOW FUEL WARNING IN THE R FUEL TANK; DIVERT FOR LNDG. FUEL CAP MISSING.

Narrative: ON APR/XA/06; I WAS ACTING AS PIC ON A COMMERCIAL XCOUNTRY WITH MY INSTRUCTOR. THE FLT WAS FROM MER-BFL. AT BFL I REFUELED THE ACFT AND WE BEGAN OUR RETURN FLT TO MER. ENRTE; WE RECEIVED A LOW FUEL INDICATION ON OUR R TANK; AND DIVERTED TO THE CLOSEST ARPT; FAT. WHILST SITTING IN THE FBO WE WERE INFORMED THAT THE L FUEL CAP WAS MISSING. AS PIC I DECIDED TO GND THE AIRPLANE AND RETURN TO MER FROM FAT BY TAXI. WITH THE FUEL CAP MISSING; MY INSTRUCTOR ADVISED ME TO CALL BFL AND INFORM THEM THAT WE WERE MISSING A FUEL CAP. MY INSTRUCTOR'S FIRST THOUGHTS WERE THAT 'HE HOPED IT WAS NOT ON THE RWY AT BFL; AND ACTIONS WERE TAKEN TO ADVISE THEM TO DO A RWY SWEEP.' I AM CERTAIN THAT THE FUEL CAP MUST HAVE BECOME LOOSE INFLT. THIS IS BECAUSE I MAKE IT A HABIT TO ALWAYS DOUBLECHK MY FUEL CAPS AFTER I REFUEL; OR AFTER AN FBO FUELS MY AIRPLANE; MY INSTRUCTOR ALWAYS ENFORCES THAT I DO THIS.

Data retrieved from NASA's ASRS site as of January 2009 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.