Narrative:

Preflted had brought out 'dipsticks' to calibrate for fuel quantity. Called line service to top off tanks. He fueled. I had taken off left fuel cap. He finished. I finished preflight, taxied out to runway 12, cleared for takeoff. Just lifted off, when passenger in left seat pointed to fuel filler -- no cap. Cut power, landed and taxied back to ramp to look for cap. Called line service. We subsequently found on runway 12 about 200 yards from beginning point of takeoff roll. Basic problem: my preflight routine was changed by thinking of calibrating fuel tanks. In future will be much more careful.

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Original NASA ASRS Text

Title: AFTER FUELING AND AT LIFT OFF PAX NOTED L WING FUEL CAP WAS MISSING. ACFT PUT BACK ON GND AND SEARCH MADE FOR FUEL CAP. FOUND ON RWY.

Narrative: PREFLTED HAD BROUGHT OUT 'DIPSTICKS' TO CALIBRATE FOR FUEL QUANTITY. CALLED LINE SVC TO TOP OFF TANKS. HE FUELED. I HAD TAKEN OFF L FUEL CAP. HE FINISHED. I FINISHED PREFLT, TAXIED OUT TO RWY 12, CLRED FOR TKOF. JUST LIFTED OFF, WHEN PAX IN L SEAT POINTED TO FUEL FILLER -- NO CAP. CUT PWR, LANDED AND TAXIED BACK TO RAMP TO LOOK FOR CAP. CALLED LINE SVC. WE SUBSEQUENTLY FOUND ON RWY 12 ABOUT 200 YARDS FROM BEGINNING POINT OF TKOF ROLL. BASIC PROBLEM: MY PREFLT ROUTINE WAS CHANGED BY THINKING OF CALIBRATING FUEL TANKS. IN FUTURE WILL BE MUCH MORE CAREFUL.

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.