Narrative:

Immediately after takeoff; tower reported smoke coming off of the back of the airplane. I requested a 180 degree to landing runway 34 and was cleared to land. Upon rollout tower informed me that the right fuel cap was hanging from its chain. The 'smoke' was believed to be the fuel being vacuumed from the open right tank. After checking the fuel level I must have incorrectly fastened the cap. The best practice to prevent the situation from reoccurring is to physically check that the fuel caps are correctly secured.

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Original NASA ASRS Text

Title: FUEL STREAMING OUT OF OPEN GAS CAP IS MISIDENTIFIED BY ATCT LCL CTLR AS SMOKE. C206 PLT MAKE IMMEDIATE RETURN AND LNDG.

Narrative: IMMEDIATELY AFTER TKOF; TWR RPTED SMOKE COMING OFF OF THE BACK OF THE AIRPLANE. I REQUESTED A 180 DEG TO LNDG RWY 34 AND WAS CLRED TO LAND. UPON ROLLOUT TWR INFORMED ME THAT THE R FUEL CAP WAS HANGING FROM ITS CHAIN. THE 'SMOKE' WAS BELIEVED TO BE THE FUEL BEING VACUUMED FROM THE OPEN R TANK. AFTER CHKING THE FUEL LEVEL I MUST HAVE INCORRECTLY FASTENED THE CAP. THE BEST PRACTICE TO PREVENT THE SITUATION FROM REOCCURRING IS TO PHYSICALLY CHK THAT THE FUEL CAPS ARE CORRECTLY SECURED.

Data retrieved from NASA's ASRS site as of May 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.