What happened
A flight traveling from Juneau, Alaska, toward King Salmon, Alaska, under visual flight rules, requested a transition to instrument flight rules when positioned 50 miles southwest of the Yakutat VOR. After receiving clearance to proceed via the Middleton Island VOR and King Salmon VOR, the pilot reported to Air Route Traffic Control Center that the right engine had detached from the aircraft while 20 miles northwest of Middleton Island.
Following the mechanical failure, the pilot attempted an emergency descent to land at Middleton Island. However, the aircraft type experienced a continuous loss of altitude during the maneuver. The aircraft passed the island and was located southeast of the facility before radar contact was terminated.
Search efforts by rescue aircraft identified an oil slick, bubbles, and various pieces of debris floating in the ocean. These items were located roughly 3 miles south of the Middleton Island Airport. The aircraft was not recovered.
Findings
At the time of the incident, weather conditions at the Middleton Island Airport included a ceiling of 600 feet broken and visibility of 5 miles, with winds originating from 117 degrees at 17 knots, gusting to 25 knots.