What happened
During a personal cross-country flight at 6,000 feet MSL, the pilot of the aircraft experienced a crew alerting system message indicating low oil pressure, which was immediately followed by a complete loss of engine power. Following the engine failure, air traffic control provided vectors toward a nearby airport, but the pilot determined the aircraft could not reach the runway. The pilot proceeded to feather the propeller and shut off the fuel and engine power.
To avoid further complications, the pilot executed a forced landing into a sports field with the landing gear and flaps in the retracted position. During the descent, the aircraft struck trees and the ground before coming to an upright stop. There were 0 fatalities and no injuries reported.
Findings
Investigation of the engine revealed no mechanical malfunctions or pre-impact anomalies that would have prevented normal operation. Instead, internal components showed evidence of having wind-milled during the impact, having ingested unburned organic debris.
Flight data analysis showed that approximately five minutes prior to the power loss, the aircraft was flying on a constant heading and altitude but was experiencing a side-slip condition, characterized by a bank angle of 8 to 10 degrees and lateral g-forces. While the autopilot was engaged, the yaw damper system's automatic rudder trim was not active, likely because the pilot had inadvertently disengaged it.
This prolonged uncoordinated flight caused the fuel tank feed line to unport. While the fuel system is designed to handle momentary uncoordinated flight, it could not sustain the fuel flow during this extended period of side-slipping. The loss of engine power was a direct result of this fuel unporting caused by uncoordinated flight.