Narrative:

I [departed] on a pleasure flight after five weeks of not being able to fly my airplane. I performed what I thought was a thorough enough of a pre-flight inspection. I topped my right tank and departed with the fuel valve in the right tank position. After traveling approximately 25 miles I decided to switch to my left tank and after approximately one minute the engine lost power. I tried switching back to the right tank and started the electric pump; but I could not regain power. At this time I had descended to approximately 400 feet AGL and decided my only course of action was to land the plane. I had been passing over a pasture when the failure occurred and; once I lost power; I banked back towards the pasture. I lined up my approach as best I could and set the plane down in as normal a landing as possible. The pasture was rough and the roll out was extremely rough with the nose gear collapsing at the every end of the rollout. There were no injuries or other property damage incurred due to this incident. The incident was reported to the FAA; and the next day I met the FAA inspectors at the site. The left wing tank cap was leaking fuel at this time. It is evident to me that the cap did not seal properly the last time it was fueled. After checking the fuel as it was being prepared to be drained; an amount of water was discovered in the fuel coming from the left tank. I inspected the seal on the cap and could not discern any problems with the o-ring gasket. Although I did not discover the water prior to takeoff; I have learned a valuable lesson. I feel that I had gotten complacent in my approach to the pre-flight in that I never found condensed water in my tanks before due to keeping them full at all times. Evidently water had intruded into the tank via the fuel cap but I did not find it in my quick sump check. Also; I will mind my fuel caps much more closely in the future. Routine replacement of the o-ring seals will become part of my annual inspection routine. Although I do not consider my self lackadaisical; I do know I can do a better job in my pre-flight routine.

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Original NASA ASRS Text

Title: An AA5 pilot suffered engine failure after switching tanks and landed in a plowed field; suffering a collapse of the nose gear. Water in the left fuel tank was the apparent cause.

Narrative: I [departed] on a pleasure flight after five weeks of not being able to fly my airplane. I performed what I thought was a thorough enough of a pre-flight inspection. I topped my right tank and departed with the fuel valve in the right tank position. After traveling approximately 25 miles I decided to switch to my left tank and after approximately one minute the engine lost power. I tried switching back to the right tank and started the electric pump; but I could not regain power. At this time I had descended to approximately 400 feet AGL and decided my only course of action was to land the plane. I had been passing over a pasture when the failure occurred and; once I lost power; I banked back towards the pasture. I lined up my approach as best I could and set the plane down in as normal a landing as possible. The pasture was rough and the roll out was extremely rough with the nose gear collapsing at the every end of the rollout. There were no injuries or other property damage incurred due to this incident. The incident was reported to the FAA; and the next day I met the FAA inspectors at the site. The left wing tank cap was leaking fuel at this time. It is evident to me that the cap did not seal properly the last time it was fueled. After checking the fuel as it was being prepared to be drained; an amount of water was discovered in the fuel coming from the left tank. I inspected the seal on the cap and could not discern any problems with the O-ring gasket. Although I did not discover the water prior to takeoff; I have learned a valuable lesson. I feel that I had gotten complacent in my approach to the pre-flight in that I never found condensed water in my tanks before due to keeping them full at all times. Evidently water had intruded into the tank via the fuel cap but I did not find it in my quick sump check. Also; I will mind my fuel caps much more closely in the future. Routine replacement of the O-ring seals will become part of my annual inspection routine. Although I do not consider my self lackadaisical; I do know I can do a better job in my pre-flight routine.

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.