Narrative:

After a full complete preflight preparation; conducted in accordance with far 91.103; and which included; but was not limited to WX briefing and review of NOTAMS; I conducted a thorough preflight inspection of the aircraft; following the poh. I checked the fuel level in both tanks through physical observation by opening the caps and looking into and measuring the fuel level in both tanks. From this and the fact that I had topped off the fuel in both tanks before a previous flight of only 30 mins in duration; it was determined that there was more than the required amount of fuel in each tank for my flight. The tach hour meter was duly noted: I went for a local flight. After 1 hour of flight; I returned to land at ZZZ which was my departure airport. On completion of the turn from base to final; the engine quit. Following all appropriate procedures; I attempted to get the engine restarted; but was unable to do so. It would not restart. I was now in an in-flight emergency that required immediate action. I determined that it would be extremely unwise and dangerous to attempt to make the airfield by trying to stretch the glide. With no other options available to me; I made the decision; after ensuring there was no traffic or other hazard in the area; to make an emergency landing in the vicinity of the road. The aircraft proceeded on the ground for some distance before becoming inverted. This was not a case of fuel exhaustion. As stated above; I had carefully checked the fuel level in both tanks. Further; fuel was observed draining from the aircraft as it was being righted after being inverted after the accident and there was fuel remaining in the tanks when the aircraft was delivered to the hangar. At this point in time I do not know why the engine quit.

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Original NASA ASRS Text

Title: UNEXPLAINED ENGINE FAILURE RESULTS IN OFF ARPT EMERGENCY LANDING FOR C150 PLT.

Narrative: AFTER A FULL COMPLETE PREFLT PREPARATION; CONDUCTED IN ACCORDANCE WITH FAR 91.103; AND WHICH INCLUDED; BUT WAS NOT LIMITED TO WX BRIEFING AND REVIEW OF NOTAMS; I CONDUCTED A THOROUGH PREFLT INSPECTION OF THE ACFT; FOLLOWING THE POH. I CHKED THE FUEL LEVEL IN BOTH TANKS THROUGH PHYSICAL OBSERVATION BY OPENING THE CAPS AND LOOKING INTO AND MEASURING THE FUEL LEVEL IN BOTH TANKS. FROM THIS AND THE FACT THAT I HAD TOPPED OFF THE FUEL IN BOTH TANKS BEFORE A PREVIOUS FLT OF ONLY 30 MINS IN DURATION; IT WAS DETERMINED THAT THERE WAS MORE THAN THE REQUIRED AMOUNT OF FUEL IN EACH TANK FOR MY FLT. THE TACH HR METER WAS DULY NOTED: I WENT FOR A LOCAL FLT. AFTER 1 HR OF FLT; I RETURNED TO LAND AT ZZZ WHICH WAS MY DEP ARPT. ON COMPLETION OF THE TURN FROM BASE TO FINAL; THE ENG QUIT. FOLLOWING ALL APPROPRIATE PROCS; I ATTEMPTED TO GET THE ENG RESTARTED; BUT WAS UNABLE TO DO SO. IT WOULD NOT RESTART. I WAS NOW IN AN INFLT EMER THAT REQUIRED IMMEDIATE ACTION. I DETERMINED THAT IT WOULD BE EXTREMELY UNWISE AND DANGEROUS TO ATTEMPT TO MAKE THE AIRFIELD BY TRYING TO STRETCH THE GLIDE. WITH NO OTHER OPTIONS AVAILABLE TO ME; I MADE THE DECISION; AFTER ENSURING THERE WAS NO TFC OR OTHER HAZARD IN THE AREA; TO MAKE AN EMER LNDG IN THE VICINITY OF THE ROAD. THE ACFT PROCEEDED ON THE GND FOR SOME DISTANCE BEFORE BECOMING INVERTED. THIS WAS NOT A CASE OF FUEL EXHAUSTION. AS STATED ABOVE; I HAD CAREFULLY CHKED THE FUEL LEVEL IN BOTH TANKS. FURTHER; FUEL WAS OBSERVED DRAINING FROM THE ACFT AS IT WAS BEING RIGHTED AFTER BEING INVERTED AFTER THE ACCIDENT AND THERE WAS FUEL REMAINING IN THE TANKS WHEN THE ACFT WAS DELIVERED TO THE HANGAR. AT THIS POINT IN TIME I DO NOT KNOW WHY THE ENG QUIT.

Data retrieved from NASA's ASRS site as of January 2009 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.