Narrative:

After refuel operation completed by ground crew, fuel cap was not put back on and aircraft departed. At 500 ft AGL, the rear passenger noticed 'a mist' passing the rear window. I slowed the aircraft to 40 KIAS and flew 1 mi to boi and landed. No damage was done. The aircraft was refueled, no leaks detected. Aircraft was returned to service.

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Original NASA ASRS Text

Title: PLT DEPARTS AFTER REFUELING AND HAS FUEL SIPHONING. MAKES A RETURN TO BASE AND DETERMINES FUEL CAP IS MISSING.

Narrative: AFTER REFUEL OP COMPLETED BY GND CREW, FUEL CAP WAS NOT PUT BACK ON AND ACFT DEPARTED. AT 500 FT AGL, THE REAR PAX NOTICED 'A MIST' PASSING THE REAR WINDOW. I SLOWED THE ACFT TO 40 KIAS AND FLEW 1 MI TO BOI AND LANDED. NO DAMAGE WAS DONE. THE ACFT WAS REFUELED, NO LEAKS DETECTED. ACFT WAS RETURNED TO SVC.

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.