Narrative:

The incident occurred during the second flight of the day. Before beginning the first flight of the day, I filled the aircraft fuel tanks. I then flew a 1 hour flight to pick up a passenger. The incident occurred approximately 20 mins after takeoff on the second flight, with the passenger on board. The right fuel filler cap had come loose at some point during the 2 flts, causing all the fuel to be siphoned overboard, resulting in fuel starvation. The engine quit, and I was able to glide to a pasture and land safely. There were no injuries and no damage to the aircraft. After landing, an a&P examined the aircraft and concluded there was no damage. We put 10 gallons of fuel into the tanks, and, after mowing and carefully inspecting an adequate length of pasture to use as a runway, I flew the aircraft to the nearest airport, cherokee village, ar. By coincidence, the pasture had been used as a private airstrip several yrs previously, and was quite smooth. At cherokee village, I filled the tanks, and flew the aircraft to its home base. The fuel filler caps on the aircraft are made by monarch, and are threaded so they simply screw into the tops of the tanks. I cannot imagine how they could work their way loose in-flight, so I assume I failed to secure the right cap after filling the tanks before the first flight. Since the aircraft was a C182, and since the filler caps are on top of the wing, I normally take advantage of being up on a ladder while fueling to inspect the top of the aircraft. I do not remember either securing the caps or failing to secure them.

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Original NASA ASRS Text

Title: A C182K IN CRUISE DECLARED AN EMER AND LANDED OFF ARPT DUE TO FUEL STARVATION CAUSED BY THE R TANK FILL CAP OFF.

Narrative: THE INCIDENT OCCURRED DURING THE SECOND FLT OF THE DAY. BEFORE BEGINNING THE FIRST FLT OF THE DAY, I FILLED THE ACFT FUEL TANKS. I THEN FLEW A 1 HR FLT TO PICK UP A PAX. THE INCIDENT OCCURRED APPROX 20 MINS AFTER TKOF ON THE SECOND FLT, WITH THE PAX ON BOARD. THE R FUEL FILLER CAP HAD COME LOOSE AT SOME POINT DURING THE 2 FLTS, CAUSING ALL THE FUEL TO BE SIPHONED OVERBOARD, RESULTING IN FUEL STARVATION. THE ENG QUIT, AND I WAS ABLE TO GLIDE TO A PASTURE AND LAND SAFELY. THERE WERE NO INJURIES AND NO DAMAGE TO THE ACFT. AFTER LNDG, AN A&P EXAMINED THE ACFT AND CONCLUDED THERE WAS NO DAMAGE. WE PUT 10 GALLONS OF FUEL INTO THE TANKS, AND, AFTER MOWING AND CAREFULLY INSPECTING AN ADEQUATE LENGTH OF PASTURE TO USE AS A RWY, I FLEW THE ACFT TO THE NEAREST ARPT, CHEROKEE VILLAGE, AR. BY COINCIDENCE, THE PASTURE HAD BEEN USED AS A PVT AIRSTRIP SEVERAL YRS PREVIOUSLY, AND WAS QUITE SMOOTH. AT CHEROKEE VILLAGE, I FILLED THE TANKS, AND FLEW THE ACFT TO ITS HOME BASE. THE FUEL FILLER CAPS ON THE ACFT ARE MADE BY MONARCH, AND ARE THREADED SO THEY SIMPLY SCREW INTO THE TOPS OF THE TANKS. I CANNOT IMAGINE HOW THEY COULD WORK THEIR WAY LOOSE INFLT, SO I ASSUME I FAILED TO SECURE THE R CAP AFTER FILLING THE TANKS BEFORE THE FIRST FLT. SINCE THE ACFT WAS A C182, AND SINCE THE FILLER CAPS ARE ON TOP OF THE WING, I NORMALLY TAKE ADVANTAGE OF BEING UP ON A LADDER WHILE FUELING TO INSPECT THE TOP OF THE ACFT. I DO NOT REMEMBER EITHER SECURING THE CAPS OR FAILING TO SECURE THEM.

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.