Narrative:

[After departure] I flew for about an hour and stopped for fuel. My next planned stop to be a 300 SM mile leg. The plane holds 24 gallons of fuel; burns 6 gal an hour for 4 hours of flight; and this would be a 3 hour flight leaving an hour fuel reserve. There is a fuel totalizer that I had checked against the actual fuel used and had been spot on. There are also clear fuel sight gauges at each wing root and had been checking those vs. The fuel totalizer. I had been flying for about 2.5 hours and when I checked the sight gauges [there was] just a trace of fuel to be seen. I checked the totalizer and it indicated that there should be 6 gallons of fuel. My decision then was to land as soon as possible then the engine lost rpm; I rocked the wings to see if I could see any fuel showing in the sight gauges. There was barely any to be seen. The process of rocking the wings gave my power back for a couple of minutes while I looked for a suitable landing site. Then I lost power so I set up for the site I had chosen which was a stubble field near a road and nearby were some houses. I went through my emergency check list and called 121.5 and prepared to land. Right away I knew that the outcome would be a nonevent as the plane is a bush type plane. I tried to re-contact the emergency frequency to let them know that there was not a problem other than needing some fuel but was unable to contact them on my radio. After I shut down I used my cell and called FSS to let them know. They had already notified the sheriff and the sheriff was on scene in about 10 minutes; helped me get some 100LL. I discovered on landing that the left fuel cap which has a vent that must be pointed forward was on backwards that caused the fuel to be siphoned from the tank. I added 8 gallons of fuel. Checking the fuel caps is a normal part of my preflight however I was distracted by a person that came by to look at my airplane and he was asking questions about the plane; so I think I missed the fact that the fuel cap was on the wrong direction. A vivid lesson not to be forgotten.

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Original NASA ASRS Text

Title: Carbon Cub pilot reported executing an uneventful forced landing after experiencing fuel exhaustion related to improper fuel cap orientation.

Narrative: [After departure] I flew for about an hour and stopped for fuel. My next planned stop to be a 300 SM mile leg. The plane holds 24 gallons of fuel; burns 6 gal an hour for 4 hours of flight; and this would be a 3 hour flight leaving an hour fuel reserve. There is a fuel totalizer that I had checked against the actual fuel used and had been spot on. There are also clear fuel sight gauges at each wing root and had been checking those vs. the fuel totalizer. I had been flying for about 2.5 hours and when I checked the sight gauges [there was] just a trace of fuel to be seen. I checked the totalizer and it indicated that there should be 6 gallons of fuel. My decision then was to land as soon as possible then the engine lost rpm; I rocked the wings to see if I could see any fuel showing in the sight gauges. There was barely any to be seen. The process of rocking the wings gave my power back for a couple of minutes while I looked for a suitable landing site. Then I lost power so I set up for the site I had chosen which was a stubble field near a road and nearby were some houses. I went through my emergency check list and called 121.5 and prepared to land. Right away I knew that the outcome would be a nonevent as the plane is a bush type plane. I tried to re-contact the emergency frequency to let them know that there was not a problem other than needing some fuel but was unable to contact them on my radio. After I shut down I used my cell and called FSS to let them know. They had already notified the Sheriff and the Sheriff was on scene in about 10 minutes; helped me get some 100LL. I discovered on landing that the left fuel cap which has a vent that must be pointed forward was on backwards that caused the fuel to be siphoned from the tank. I added 8 gallons of fuel. Checking the fuel caps is a normal part of my preflight however I was distracted by a person that came by to look at my airplane and he was asking questions about the plane; so I think I missed the fact that the fuel cap was on the wrong direction. A vivid lesson not to be forgotten.

Data retrieved from NASA's ASRS site 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.