What happened
During the initial climb phase of a flight, the left engine of a twin-engine airplane failed. In response, the pilot feathered the left propeller and decided to return to the airport for an emergency landing. While on final approach, the pilot experienced excessive speed, causing the aircraft to overshoot the runway. At the midfield point of the runway, the pilot initiated a single-engine go-around.
During this maneuver, the aircraft's landing gear remained extended, and the flaps were set at approximately 15 degrees. This configuration significantly reduced the aircraft's climb performance. The airplane subsequently lost altitude and struck the roof of a single-story industrial building before hitting trees and a landscape embankment. The impact occurred approximately 0.5 miles from the airport. A witness observed the aircraft attempting to land twice on the same approach, ballooning both times before the final go-around.
Findings
An investigation into the left engine revealed that the starter adapter shaft gear had failed. Maintenance records showed that the engine had accumulated roughly 1,270 hours since its last overhaul in July 1998. Crucially, the engine maintenance logs indicated that the crew had not complied with Teledyne Continental Motors Service Bulletin CSB94-4 (and its successor MSB94-4F) since the 1998 overhaul. This specific bulletin required a visual inspection of the starter adapter every 400 hours to prevent gear failure. Failure to perform required inspections led to the mechanical breakdown of the starter adapter shaft gear.