NTSB investigators either traveled in support of this investigation or conducted a significant amount of investigative work without any travel, and used data obtained from various sources to prepare this aircraft accident report.
According to air traffic control records, the pilot reported that the airplane had experienced a total loss of engine power during cruise climb about 4.5 minutes after the cargo flight’s departure. After the loss of engine power, the pilot reported that his forward visibility was restricted by engine oil on the airplane's windshield. The pilot completed a forced landing to an open field, but the airplane impacted a hedgerow during the landing roll.
A postaccident engine disassembly revealed a failure of the gas generator due to a compressor turbine blade separation. The fractured compressor turbine blade released into the engine gas flow path and subsequently impacted adjacent compressor turbine blades and downstream components, which caused the loss of engine power. A metallurgical examination established that the blade had failed in high-cycle fatigue that originated from the blade trailing edge. However, the root cause of the fatigue could not be determined due to secondary damage sustained to the fracture surface. All other mechanical damage to the engine was consistent with collateral damage sustained subsequent to the release of the compressor turbine blade. Engine oil was observed on the downstream side of the power turbine disk; any engine oil that entered the gas flow path at that location would have been discharged through the exhaust ducts and into the outside airstream, and this was likely the source of the engine oil observed on the exterior of the airframe. Recovered engine parameter data indicated normal engine operation until the sudden loss of power. Additional data analysis did not reveal any abnormal engine parameter trends.