What happened
During the takeoff ground run, witnesses observed that while the engine sound appeared normal, the aircraft remained on the runway for an unusually long period. As the aircraft finally lifted off near the end of the runway, the angle of attack increased beyond normal levels. The aircraft continued to climb in this attitude, characterized by the wings wagging up and down.
Upon reaching an altitude of approximately 100 to 200 feet, the nose and right wing dropped toward the ground. The aircraft collided with the ground roughly one-half mile north of the airport in a nose-down, right-wing-low attitude. A post-crash fire ignited and consumed the aircraft.
The investigation
An examination of the engine during teardown revealed that the number six cylinder could not maintain compression. Further inspection showed that a section of the cylinder around the exhaust seal was missing. A metallurgical examination determined that this damage was most likely caused by detonation resulting from extremely lean operating conditions.
Findings
The pilot had recently purchased the aircraft, which featured a turbocharger. The pilot had been instructed to lean the mixture for takeoff; however, the operator's manual specifies that the mixture should be set to full rich during the takeoff phase.