What happened
During a night medical transport flight, a twin-engine turbine-powered aircraft departed with a pilot, two medical crew members, and one patient. While performing the initial climb under night visual meteorological conditions, the aircraft deviated from its runway heading by approximately 30 degrees to the left. Witnesses observed the plane cease its ascent, execute an abrupt left bank, and begin a rapid descent. The aircraft subsequently struck a parking lot, where it caught fire.
Findings
Investigation into the aircraft's recent maintenance history revealed that the crew had reported power imbalances between the left and right engines on three separate occasions during the two months preceding the crash. Maintenance personnel had attempted to rectify this by replacing the left engine's bleed valve three times, with the most recent replacement occurring only three days prior to the accident. Additionally, the fuel control unit on the left engine had been replaced roughly one month before the event while addressing an oil leak.
Post-accident analysis of the engines and propellers showed that the right engine and propeller exhibited more significant rotational signatures than the left side. This evidence suggests that the left engine was producing significantly less power or was at a low power setting at the moment of impact. The observed flight path, characterized by a sharp left bank and descent, is consistent with a loss of power in the left engine during the climb phase. However, the severity of the impact and the resulting fire prevented investigators from determining the specific mechanical failure that caused the left engine to lose power.