Accident Sequence
While in cruise flight during daytime visual meteorological conditions, the pilot experienced a loss of engine power. The pilot executed an approach to Interstate Highway I85. During the approach, the aircraft collided with an overpass support column at an altitude of 15 feet above ground level.
Aircraft and Maintenance History
The engine had been overhauled 51 hours prior to the accident. Overhaul records indicated that a magneto repair was performed. Annual inspection records showed compliance with Airworthiness Directive (AD) 78-09-07, which pertains to magnetos. Post-crash evidence indicated that the overhaul was inadequate; specifically, the carburetor and magneto were not overhauled during the procedure. The mechanic who performed the overhaul had a lengthy history of Federal Aviation Administration (FAA) violations for improper repairs.
Post-Crash Examination
Post-crash testing revealed that the left magneto was firing intermittently. The carburetor throttle valve seals were leaking, inducing a lean mixture. The carburetor accelerator pump was found to be weak. During a post-crash engine run, the engine hesitated when the throttle was jammed.
Pilot Information
The pilot in command received a private pilot certificate in September 1973.