What happened
Radar monitoring showed the aircraft descending along a direct path from flight level 380, following instructions to reach 13,000 feet for a VOR approach to the destination. During this descent, the pilot acknowledged the termination of radar services and received instructions to transition to the airport advisory frequency. At the moment of this final communication, the aircraft was recorded at an altitude of 14,000 feet.
Following the transmission, the aircraft continued a steady descent, leveling off at 13,000 feet. Approximately two and a half minutes later, the aircraft initiated a right-hand turn to begin the outbound procedure turn. While the approach instructions required a minimum altitude of 8,200 feet during this maneuver, the aircraft dropped to 12,900 feet before experiencing a sudden loss of 1,600 feet in just ten seconds. This rapid descent marked the final radar contact.
Eyewitness accounts from the airport area described hearing fluctuating engine noises, characterized by loud sounds followed by softer periods, lasting several seconds. Another observer noted an aircraft flying below the cloud layer, executing a right turn with a steep nose-low pitch of approximately 75 to 80 degrees. This aircraft completed several turns, with the turning radius decreasing as the altitude dropped, before it was obscured by the terrain.
Findings
Post-accident inspections of the engines, systems, and airframe showed no mechanical failures or anomalies that would have prevented standard operation. Anti-ice fluid was present on the leading edges of the tail and wing panels. Meteorological reports for the region indicated an active AIRMET, noting that the freezing level ranged between 4,000 and 10,000 feet, with potential for icing extending up to 20,000 feet.