What happened
Six hours before reporting for duty, the pilot visited a doctor and was diagnosed with fatigue, reflux symptoms, and gastritis. Shortly before takeoff, the pilot informed a fellow company pilot that he felt ill, noting a concern regarding potential repercussions from his employer if he chose to ground himself.
A few minutes before contact was lost with air traffic control, the pilot radioed a colleague flying in another company aircraft on the same route, stating, "I don't feel so good...I feel like I'm going to toss my cookies."
The wreckage was located approximately 11 hours after the disappearance. The pilot was fatally injured inside the aircraft.
The investigation
Analysis of the wreckage distribution at the accident site indicated that the right wing and horizontal stabilator had separated from the aircraft during flight. Subsequent examinations determined that these separations were caused by overstress. Aside from the separation of the wing and stabilator, no mechanical problems were identified in the wreckage.
Investigators also reviewed the pilot's activities leading up to the accident. During the two-day rest period preceding the flight, the pilot's schedule was found to be inconsistent with his assigned night air cargo duties.