What happened
During a dusk approach under instrument meteorological conditions (IMC), the aircraft was executing an ILS approach while encountering icing conditions. As the pilot descended through an overcast layer on final approach, the engine experienced a sudden loss of power that failed to respond to throttle inputs. The crew performed a forced landing in a wooded area located short of the runway. The impact resulted in extensive damage to the airframe and caused three serious injuries among the occupants.
At the time of the incident, surface temperatures were recorded at 36°F with a dew point of 35°F. A passenger noted visible ice accumulation on the wings while descending through clouds. Investigation of the cockpit revealed that the pitot heat, stall warning heat, and ice light switches were all set to the 'off' position.
Findings
Post-accident inspection of the engine revealed that the turbocharger and wastegate transition pipes had separated at the flange. While carbon residue was present at the separation point, no evidence of heat damage was observed. Notably, the hardware intended to secure the pipes—including the gasket, bolts, washers, and self-locking nuts—was missing from the assembly. During the investigation, three other instances of similar pipe separation were identified in another aircraft, though those incidents only resulted in partial power loss. The engine was able to run successfully during subsequent operational checks. Loss of engine power for undetermined reasons was determined to be the primary cause, with low light levels and the presence of trees in the landing site acting as contributing factors.