What happened
During a night visual approach, the pilot of the aircraft reported descending from 6,000 feet and confirmed the airport was visible. After receiving clearance for the approach, the pilot requested to cancel the IFR clearance and transition to a traffic advisory frequency, which was granted. Following this communication, no further radio transmissions were received from the flight.
Radar tracking indicated the aircraft was positioned southeast of the airport, traveling on a westerly heading. At approximately 2035, the aircraft crossed a river and initiated a sharp left turn that moved it away from the airport. During this maneuver, the aircraft completed roughly 90 degrees of the turn before disappearing from radar. The final radar contact placed the aircraft on the western side of the river, near the site where the wreckage was later found.
Subsequent recovery efforts retrieved highly fragmented wreckage from the riverbed after it had been submerged for several weeks. Post-accident inspections of the engines revealed that the right engine was operational and rotating at the moment of impact. However, the left engine was found to be non-operational, with the left propeller in a feathered position.
Findings
Investigation of the engines and airframe systems showed no evidence of pre-existing mechanical issues or system failures that would have prevented normal operation. Investigators could not identify a specific cause for the unexplained shutdown of the left engine during the flight.