What happened
Prior to departure, the pilot received two weather briefings that forecasted precipitation, very moist and unstable air, occasional moderate turbulence, and isolated severe turbulence. The flight took place on a dark night with multiple cloud layers present.
After departing while carrying bank cargo, the pilot began a climb in IMC toward 6,000 feet, traveling in a northwest direction parallel to the coastline. During the flight, the pilot initiated a southwest turn that was initially perpendicular to the intended course. While continuing this left turn, radar contact with the aircraft was lost. The airplane suddenly entered an uncontrolled descent from 4,400 feet to sea level, lasting approximately 15 seconds.
The main wreckage was located 1,000 feet below sea level, approximately 0.2 miles from the aircraft's last known radar position. Underwater video footage revealed that the aircraft had fragmented into more than 200 pieces. The wreckage was not recovered.