Incident
According to a statement from the Jacksonville Center air traffic control (ATC) facility, the pilot initially contacted ATC while at flight level 270. Approximately 25 minutes later, the aircraft began to deviate from its ATC-assigned altitude and route. The controller’s repeated attempts to establish communication with the pilot were unsuccessful.
In response, the North American Aerospace Defense Command launched military fighter aircraft to intercept the airplane. The military pilots observed the airplane circling in a left turn at a high altitude and low airspeed, with its windows partially frosted over. They reported seeing the pilot slumped over in the cockpit and unresponsive. The military aircraft fired flares, but the pilot continued to show no response.
The airplane continued to circle for about three hours before descending into the Gulf of Mexico and sinking. Neither the pilot nor the aircraft were recovered.
Investigation
A review of the pilot’s Federal Aviation Administration (FAA) medical records revealed no recent medical conditions that would have deemed him unfit to fly.
Probable Cause
The official probable cause, as determined by the investigation, was pilot incapacitation, which resulted in the pilot’s inability to maintain airplane control and the airplane’s subsequent ocean impact.