What happened
During a VFR cross-country flight, the aircraft experienced an in-flight breakup. While in contact with the Cleveland Air Route Traffic Control Center, the pilot reported being at an altitude of 16,500' MSL and described the conditions as "in the soup." Radar data from the control center indicated that during the 30 minutes preceding the accident, the aircraft performed several altitude and heading excursions. Just before the aircraft disappeared from radar, its flight track deviated to the right. A witness reported hearing a loud "pop" and observed the plane descending with a large section of one wing missing. The wreckage was found scattered over an area of approximately 1.5 miles.
The investigation
An examination of the wreckage revealed that the right wing failed due to positive overload at a point approximately 9 feet inboard from the wing tip. This failure caused the wing section to strike the right horizontal stabilizer, which subsequently separated from the aircraft. Investigators found no evidence of any pre-existing defects in the structure. Additionally, an inspection of the aircraft's equipment determined that there was no supplemental oxygen onboard the plane.