Decathlon pilot reported landing in a field after the engine quit in flight for unknown reasons.

Narrative:

I was flying in cruise when engine suddenly quit. I had been flying slightly more than 3 hours. I went to full rich on the mixture; turned on the fuel pump and the engine did not restart. I then tried each magneto to no avail. I selected a flat farm field and landed exactly where I intended to land. The first part of the terrain was relatively smooth. Toward the end of the landing roll; it became extremely rough and aircraft was shaking violently. I tried to brake to avoid going into a ditch and it suddenly flipped over on its back. I immediately turned off the switches but was unable to reach the fuel shutoff valve as the plane was on its back. I smelled gasoline. By then; people who had seen the landing came and helped me out of the airplane. The first responders arrived as did the police. I am not sure why the engine quit. I am a highly experienced decathlon pilot. I fueled the airplane and the tank were full to the brim. As I said; I flew for slightly more than 3 hours and the airplane should have had enough fuel to fly for at least 4 hours. I should have had enough fuel to land at my destination and meet the 30-minute reserve requirement. Just before the accident; the fuel gauges were indicating about 1/4 in each tank and the GPS told me that I had approximately 15 minutes of flight time to my destination.

Original NASA ASRS Text

Title: Decathlon pilot reported landing in a field after the engine quit in flight for unknown reasons.

Narrative: I was flying in cruise when engine suddenly quit. I had been flying slightly more than 3 hours. I went to full rich on the mixture; turned on the fuel pump and the engine did not restart. I then tried each magneto to no avail. I selected a flat farm field and landed exactly where I intended to land. The first part of the terrain was relatively smooth. Toward the end of the landing roll; it became extremely rough and aircraft was shaking violently. I tried to brake to avoid going into a ditch and it suddenly flipped over on its back. I immediately turned off the switches but was unable to reach the fuel shutoff valve as the plane was on its back. I smelled gasoline. By then; people who had seen the landing came and helped me out of the airplane. The first responders arrived as did the police. I am not sure why the engine quit. I am a highly experienced Decathlon pilot. I fueled the airplane and the tank were full to the brim. As I said; I flew for slightly more than 3 hours and the airplane should have had enough fuel to fly for at least 4 hours. I should have had enough fuel to land at my destination and meet the 30-minute reserve requirement. Just before the accident; the fuel gauges were indicating about 1/4 in each tank and the GPS told me that I had approximately 15 minutes of flight time to my destination.

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.

Attributes
ACN	1389295
Time
Date	201609
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Decathlon 8KCAB
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Route In Use	Direct
Flight Plan	None
Component
Aircraft Component	Engine
Person 1
Function	Pilot Flying Single Pilot
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Flight Instructor Flight Crew Instrument Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 25 Flight Crew Total 5600 Flight Crew Type 3800
Events
Anomaly	Aircraft Equipment Problem Critical Ground Event / Encounter Ground Strike - Aircraft