What happened
Prior to departure, the pilot conducted three separate weather briefings which revealed significant convective activity and a moving squall line. To avoid these conditions, the pilot initially planned a more southerly route. During the flight, the pilot requested a heading change to navigate through a perceived gap in the weather using onboard radar. An air traffic controller, who believed a clear area was available, directed the aircraft on a 120-degree heading toward a specific fix.
While maintaining a cruise altitude of 25,000 feet, the aircraft encountered a line of intense thunderstorms. Following this encounter, the aircraft began to lose altitude and attempted to reverse course. The aircraft then entered a rapid descent, experienced an in-flight breakup, and crashed into the terrain. The final communication from the pilot noted that the aircraft had encountered heavy turbulence before the plane disappeared from radar.
Findings
Investigation of the wreckage showed that the fractures on the recovered flight control surfaces were consistent with overstress failure caused by extreme forces. There was no evidence of prior structural cracks or engine anomalies.
Data analysis revealed that the air traffic controller had access to significant information regarding moderate to extreme weather along the flight path. Although the controller believed a clear path existed, recorded precipitation data and statements from a second controller contradicted this assessment. The controller failed to issue necessary weather advisories regarding the immediate hazards of the new heading, which led the aircraft into the severe thunderstorm cells.