Accident Overview
An aircraft en route from Las Vegas, Nevada, to Dalhart, Texas, crashed in an open field after the left wing detached in flight. The accident occurred following the crew's encounter with poor weather conditions, including icing and turbulence. The pilot, rated for visual flight rules (VFR) only, chose to continue flying despite the adverse conditions. Shortly afterward, the left wing suffered a structural failure and separated from the airframe. The aircraft then entered an uncontrolled descent, struck the ground, and exploded. All 11 occupants on board were killed.
Contributing Circumstances
The investigation found that the pilot attempted operation with known equipment deficiencies. The aircraft was not equipped with de-icing equipment. The pilot continued VFR flight into adverse weather conditions, which included icing, sleet, and freezing rain. The aircraft accumulated airframe ice, and the pilot exceeded the designed stress limits of the aircraft. This led to an overload failure of the airframe and wing spars. Consequently, the left wing failed and separated in flight.
Probable Cause
The official probable cause of the accident was an airframe failure in flight and uncontrolled descent, caused by the combination of the following factors: the pilot-in-command attempted operation with known deficiencies in equipment; continued VFR flight into adverse weather conditions; exceeded designed stress limits of aircraft; overload failure of airframe and wing spars; separation in flight; icing conditions including sleet and freezing rain; airframe ice; the left wing failed and separated in flight; the pilot was type rated for VFR flight only; and the aircraft was not fitted with de-icing equipment.