What happened
Prior to departure, preflight weather briefings provided to the pilot included forecasts for icing conditions along the intended route of flight and at the destination airport. The aircraft was not equipped or certificated to operate in such conditions.
During the descent toward the destination, the pilot reported encountering moderate rime icing. Approximately 35 minutes after this report, while the aircraft was on final approach, observers noted the plane's ground speed slowing to 65 knots before it entered a rapid descent. Witnesses saw the aircraft emerge from the clouds in a nose-down attitude, followed by a pitch up to a high-nose attitude, before entering a right-hand spin that ended in a crash.
The investigation
An examination of the aircraft's engine, propeller, flight controls, systems, and structure following the crash revealed no evidence of any malfunction or failure occurring prior to the impact. Additionally, a medical examination of the pilot and passenger found no evidence suggesting that incapacitation occurred before the accident.