What happened
During an instrument flight rules cross-country flight, the pilot was attempting to climb to a target altitude of 23,000 feet MSL. Radar data indicated that as the aircraft passed through 18,6 and 20,200 feet MSL, the groundspeed began to steadily decline. Shortly after reaching 20,200 feet, the aircraft transitioned into a descent toward the southeast. The flight path subsequently shifted to a northeast heading before becoming erratic, at which point all tracking data ceased. The pilot did not issue any distress signals and failed to respond to communications from air traffic control.
The wreckage was discovered in a heavily forested area at an elevation of approximately 930 feet, located roughly 1,000 feet south of the final radar contact. Investigators noted that the right aileron, the outboard section of the right wing, and the right horizontal stabilizer and elevator were missing from the primary wreckage site and were not recovered during ground or aerial searches. The main airframe and engine showed no signs of mechanical failure prior to the accident.
Findings
Meteorological evidence suggests the aircraft encountered icing conditions, ranging from light to heavy, starting at 14,000 feet MSL and continuing for approximately 16 minutes. While the aircraft was equipped for icing, the presence of freezing drizzle likely caused ice accumulation that surpassed the capacity of the onboard protection systems. This accumulation is consistent with the observed reduction in groundspeed during the climb.
The accumulation of ice likely led to an aerodynamic stall, which triggered an uncontrolled descent. The stresses of this descent caused the structural failure and the separation of the wing and tail components. Additionally, calculations determined that the aircraft was approximately 361 lbs over its maximum allowable gross weight at departure. This overload, combined with the icing, contributed to degraded flight characteristics and increased stall speeds.