What happened
During flight, the number four cylinder of the engine separated from the engine block. This mechanical failure resulted in an immediate inflight fire. Despite the severity of the event, the pilot managed to execute an emergency landing. However, the aircraft continued to burn on the ground after touchdown and was subsequently completely destroyed.
The investigation
A detailed examination of the wreckage was conducted to determine the root cause of the mechanical failure. A metallurgist analyzed the failed components and determined that the studs securing the cylinder had failed due to fatigue. This conclusion pointed to a structural material failure rather than an operational error or external impact.
Findings
The aircraft had received significant recent maintenance prior to the accident. It had undergone an annual inspection within the past 30 days and had accumulated only 20 hours of flight time since that service. Additionally, the engine itself had been overhauled 150 hours prior to the incident. These facts suggest that the fatigue failure occurred despite the relatively recent overhaul and inspection.
Safety message
Engine component failures can occur even after recent maintenance and overhaul. Regular inspections are critical for identifying potential fatigue issues before they lead to catastrophic separation.