Narrative:

I was flying an aeronca champ 7AC. About 15 minutes into the flight the engine RPM dropped. I applied full carburetor heat and full rich mixture. Engine briefly responded then 30 seconds later it quit. I was at 1200 feet and 4.2 miles east of the airport. I knew I would not make the airport so I set up a landing in a farm field below. I trimmed the plane for best glide speed and made the approach. Before landing I called mayday to alert authorities of my situation. Plane and pilot were undamaged and uninjured in landing. I alerted authorities via radio and later cell phone that neither I or the plane were damaged. Before leaving on the flight I did a complete preflight check. I inspected the control surfaces; checked the fuel gauge it read 1/4 of a tank. I visually checked tank for gasoline. No water or other contaminants appeared when sumps were checked. During run-up before takeoff no issues appeared. Both mags were fine as was carb heat. Suspecting water in the gas or some sort of contamination; purchased aviation fuel at ZZZ and took it to the airplane. I put the fuel in; checked the sumps and found no contamination. I started the plane;and did a run-up. I shut the engine down; checked for leaks; or other issues. I restarted the engine and did a high power run-up. Holding full power for over 2 minutes; no issues appeared. The engine ran perfectly. I deemed it safe to fly so I took off and flew to the originally planned destination. I purchased more fuel and drained the sumps. I then ran the engine for over 10 minutes at a high power setting. The engine ran smoothly and reliably. I flew the plane to its home base and landed. My mechanic is inspecting the aircraft to determine what caused the engine to lose power. In hindsight; I could have done a dipstick check of the tanks;that would have given me a better indication of exactly how much fuel I had. Additionally; the aircraft had not been flown in over a month before the engine out landing. The plane was put in the hangar with low fuel levels. December was a wet and cold month. Condensation in the tanks could have formed during that long period of inactivity causing or contributing to the loss of power.

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Original NASA ASRS Text

Title: An Aeronca 7AC pilot suffered an engine failure and landed in a field. Added fuel; drained the sumps; took off and flew to a nearby airport where he filled the tank; then flew the aircraft back to its home airport.

Narrative: I was flying an Aeronca Champ 7AC. About 15 minutes into the flight the engine RPM dropped. I applied full Carburetor heat and full rich mixture. Engine briefly responded then 30 seconds later it quit. I was at 1200 feet and 4.2 miles East of the airport. I knew I would not make the airport so I set up a landing in a farm field below. I trimmed the plane for best glide speed and made the approach. Before landing I called mayday to alert authorities of my situation. Plane and pilot were undamaged and uninjured in landing. I alerted authorities via radio and later cell phone that neither I or the plane were damaged. Before leaving on the flight I did a complete preflight check. I inspected the control surfaces; checked the fuel gauge it read 1/4 of a tank. I visually checked tank for gasoline. No water or other contaminants appeared when sumps were checked. During run-up before takeoff no issues appeared. Both Mags were fine as was carb heat. Suspecting water in the gas or some sort of contamination; purchased aviation fuel at ZZZ and took it to the airplane. I put the fuel in; checked the sumps and found no contamination. I started the plane;and did a run-up. I shut the engine down; checked for leaks; or other issues. I restarted the engine and did a high power run-up. Holding full power for over 2 minutes; no issues appeared. The engine ran perfectly. I deemed it safe to fly so I took off and flew to the originally planned destination. I purchased more fuel and drained the sumps. I then ran the engine for over 10 minutes at a high power setting. The engine ran smoothly and reliably. I flew the plane to its home base and landed. My Mechanic is inspecting the aircraft to determine what caused the engine to lose power. In hindsight; I could have done a dipstick check of the tanks;that would have given me a better indication of exactly how much fuel I had. Additionally; the aircraft had not been flown in over a month before the engine out landing. The plane was put in the hangar with low fuel levels. December was a wet and cold month. Condensation in the tanks could have formed during that long period of inactivity causing or contributing to the loss of power.

Data retrieved from NASA's ASRS site as of April 2012 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.