Flight and Preflight
The pilot had flown the airplane earlier on the day of the accident on a 75-mile flight. Before the return flight, he performed a preflight inspection, including taking fuel samples to check for water or contaminants. None were found. He also performed engine pre-takeoff checks, including magneto and carburetor heat checks, prior to departure.
Engine Failure and Forced Landing
The airplane took off and climbed to 3,000 feet. After about five minutes, the engine began running rough. The pilot switched fuel tanks and applied carburetor heat, but noted no improvement in engine operation. He then turned the airplane toward terrain more suitable for landing. The engine stopped making power, and the pilot executed a forced landing.
Landing and Nose-Over
During the landing, the pilot applied brakes with the yoke fully aft, and the airplane's tail would raise. He released the brakes to allow the tail to lower. The pilot repeatedly applied and released the brakes attempting to stop the airplane, but the airplane nosed over and came to rest on its top.
Post-Accident Examination
Examination of the engine after the accident revealed that the aluminum intake tubing had split outward and was fully compromised. The engine was examined; spark was produced on all magneto leads, and valve action was verified on all cylinders. One cylinder produced little compression when the engine was rotated, while all other cylinders produced compression and suction. The cylinder with low compression was removed and examined, but no defects were found.