What happened
Prior to takeoff, the pilot was advised of an active AIRMET for the area, which included precautions for occasional moderate turbulence below 14,000 feet and mountain obscuration. The forecast also indicated potential for occasional moderate rime or mixed icing, along with rain shower activity.
After departing, the pilot filed a VFR flight plan and was reminded of the existing AIRMET regarding turbulence and icing. As the flight progressed, the pilot stated his intention to climb to 11,500 feet MSL. A few minutes later, the pilot advised that he would deviate from his course to "remain VFR on these clouds." Following this transmission, there was no further communication from the aircraft.
Witnesses on the ground reported hearing a loud bang and observing the aircraft descend in a spiral below the cloud layer, with pieces of the aircraft separating. The wreckage was scattered over a one-half mile area.
The investigation
An examination of the wreckage revealed evidence that both outboard sections of the wings separated upward and rearward during flight. Additionally, the horizontal stabilator separated downward while in flight. The investigation could not verify the specific flight mode of the aircraft at the time the in-flight breakup occurred.