Narrative:

3 out of 4 fuel caps were inadvertently left off the aircraft and missed on preflight and pre takeoff checks. Aircraft was flown with caps off and returned for landing without event and replaced. Flight continued. The caps were removed for painting. The PIC was told that they were painted red. He assumed that they were replaced since all preflight paperwork released the aircraft for flight without discrepancies. The PIC did not physically touch the caps but rather looked at them in pre-dawn lighting of the wings. There was no fuel syphoning or loss during the flight and the PIC would not have known they were off had not the company called him on company frequency. The aircraft returned to point of origin after about a 17 min flight to be capped. The perception that the caps were seemingly in place occurred when the PIC was told that they were painted and his perception that they were 'black' not 'red' in color in low light of pre-dawn, including sunrise on final pre takeoff check. PIC was challenged that the caps 'looked recessed' to which the PIC said that 'is the color they look like when painted.' there is no perception of a missing cap or hole from 40 ft when not illuminated by a flashlight of 'D' cell or greater. There was no doubt that the caps were not missing until the radio call came from the company frequency. A 'look preflight' as opposed to a 'touch or close inspection preflight' in low ambient light, an assumption that 2 human beings agreed on situation with 20/20 vision, and a morning before coffee (even though there was no hurry) were factors affecting performance. We didn't see the missing caps even though we saw the location they were missing from. So much for the dreaded flashlight preflight. Preflts should be conducted in the lighted hangar before sunrise or other adequate lighting.

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Original NASA ASRS Text

Title: COMMUTER LTT TKOF WITH 3 OF ITS 4 FUEL CAPS MISSING. RETURN LAND AFTER COMPANY RADIO CALL.

Narrative: 3 OUT OF 4 FUEL CAPS WERE INADVERTENTLY LEFT OFF THE ACFT AND MISSED ON PREFLT AND PRE TKOF CHKS. ACFT WAS FLOWN WITH CAPS OFF AND RETURNED FOR LNDG WITHOUT EVENT AND REPLACED. FLT CONTINUED. THE CAPS WERE REMOVED FOR PAINTING. THE PIC WAS TOLD THAT THEY WERE PAINTED RED. HE ASSUMED THAT THEY WERE REPLACED SINCE ALL PREFLT PAPERWORK RELEASED THE ACFT FOR FLT WITHOUT DISCREPANCIES. THE PIC DID NOT PHYSICALLY TOUCH THE CAPS BUT RATHER LOOKED AT THEM IN PRE-DAWN LIGHTING OF THE WINGS. THERE WAS NO FUEL SYPHONING OR LOSS DURING THE FLT AND THE PIC WOULD NOT HAVE KNOWN THEY WERE OFF HAD NOT THE COMPANY CALLED HIM ON COMPANY FREQ. THE ACFT RETURNED TO POINT OF ORIGIN AFTER ABOUT A 17 MIN FLT TO BE CAPPED. THE PERCEPTION THAT THE CAPS WERE SEEMINGLY IN PLACE OCCURRED WHEN THE PIC WAS TOLD THAT THEY WERE PAINTED AND HIS PERCEPTION THAT THEY WERE 'BLACK' NOT 'RED' IN COLOR IN LOW LIGHT OF PRE-DAWN, INCLUDING SUNRISE ON FINAL PRE TKOF CHK. PIC WAS CHALLENGED THAT THE CAPS 'LOOKED RECESSED' TO WHICH THE PIC SAID THAT 'IS THE COLOR THEY LOOK LIKE WHEN PAINTED.' THERE IS NO PERCEPTION OF A MISSING CAP OR HOLE FROM 40 FT WHEN NOT ILLUMINATED BY A FLASHLIGHT OF 'D' CELL OR GREATER. THERE WAS NO DOUBT THAT THE CAPS WERE NOT MISSING UNTIL THE RADIO CALL CAME FROM THE COMPANY FREQ. A 'LOOK PREFLT' AS OPPOSED TO A 'TOUCH OR CLOSE INSPECTION PREFLT' IN LOW AMBIENT LIGHT, AN ASSUMPTION THAT 2 HUMAN BEINGS AGREED ON SIT WITH 20/20 VISION, AND A MORNING BEFORE COFFEE (EVEN THOUGH THERE WAS NO HURRY) WERE FACTORS AFFECTING PERFORMANCE. WE DIDN'T SEE THE MISSING CAPS EVEN THOUGH WE SAW THE LOCATION THEY WERE MISSING FROM. SO MUCH FOR THE DREADED FLASHLIGHT PREFLT. PREFLTS SHOULD BE CONDUCTED IN THE LIGHTED HANGAR BEFORE SUNRISE OR OTHER ADEQUATE LIGHTING.

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.