Incident Overview
About 15 minutes after departure, the airline transport pilot reported that the engine began to run rough and lose power. While performing engine emergency procedures, the pilot detected smoke odor in the cabin and selected a forced landing area on a river bank bordered by trees.
Forced Landing and Collision
During the landing roll, the airplane's left wing collided with a stand of trees. The airplane then pivoted 180 degrees to the left, and the left main landing gear collapsed. The airplane sustained substantial damage to the wings, fuselage, and empennage.
Post-Accident Examination
An FAA airworthiness inspector from the Anchorage Flight Standards District Office examined the wreckage on June 24th. The inspector reported that the top portion of the number four engine cylinder was separated between the cylinder barrel and the cylinder head, and that the piston connecting rod was fractured.
Additional Details
No other information regarding the aircraft type, registration, operator, or occupants was provided in the source.