What happened
While cruising at 6,000 feet, the aircraft entered atmospheric conditions characterized by icing. Following an instruction to descend to 3,6 and00 feet, the pilot communicated that the aircraft was experiencing significant power issues, specifically that one engine had lost all power and the remaining engine was operating roughly.
As the descent continued, the aircraft lost controlled flight approximately ten minutes later. During this period, the aircraft reversed its heading and struck the terrain in a near-vertical orientation.
Findings
An inspection of the feathered left engine revealed that an induction duct had degraded and started to disintegrating. Investigators discovered debris within the compressor assembly that matched the appearance of the material from the failed duct. Additionally, the examination showed that a hole had been burned through the number five piston.