Incident Details
A pilot reported airframe ice accumulating on the aircraft while cruising at 13,000 feet. To mitigate the icing, the pilot requested and was cleared to climb to 14,000 feet. Immediately upon reaching the higher altitude, the pilot lost control of the aircraft. The aircraft descended uncontrolled to 6,500 feet before the pilot was able to regain control and stabilize the flight. The pilot expressed a belief that the autopilot had failed during the event, but subsequent inspection of the autopilot system found no abnormalities or malfunctions.
Weather Conditions
At the time of the incident, towering cumulus clouds were present in all quadrants near the airport. These cloud formations are often associated with conditions conducive to airframe ice accumulation, particularly in the altitude range where the incident occurred.
Post-Flight Examination
Following the controlled landing, which was accomplished without further damage, a detailed examination of the aircraft revealed extreme buckling of the airframe structure. The structural damage suggests that the aircraft was subjected to significant aerodynamic forces during the uncontrolled descent and recovery. Despite the severity of the structural deformation, the aircraft remained intact and landed safely.
Conclusion
The incident highlights a sequence of events involving airframe ice accumulation, a subsequent loss of control at higher altitude, and a successful recovery by the pilot. The exact cause of the loss of control remains undetermined, given that neither the autopilot nor other systems exhibited faults upon inspection. The aircraft sustained substantial structural damage but was landed without additional incident.