Background
At approximately 1005 Mountain Standard Time, the pilot received a weather briefing for a planned flight to Florida with an overnight stay in Texas. The weather briefing indicated thunderstorm activity was forecast along the proposed route. The briefer specifically recommended that the pilot obtain an updated briefing before departure due to the developing thunderstorm activity and also suggested using en route flight watch services to obtain pilot reports (PIREPs) during the flight.
Sequence of Events
Later that day, at 2045, the pilot contacted the Phoenix Terminal Radar Approach Control (TRACON) and stated his intention to land at Phoenix. During this communication, the pilot indicated that he was in the clouds at an altitude of 17,500 feet. Radio and radar contact with the aircraft was lost at 2049. The wreckage was found approximately 28 miles west-northwest of Luke Air Force Base. Notably, portions of both wings were located three miles from the main wreckage site, indicating that an in-flight separation occurred.
Weather Conditions
The weather conditions at the time were challenging. The sheriff's deputy who was dispatched to the accident scene reported strong winds and heavy electrical storms in the area. Additionally, a helicopter pilot who was overhead estimated the ceiling to be 1,500 feet overcast. The official investigation findings identified the weather conditions as including clouds, low ceiling, and thunderstorms during a dark night.
Probable Cause Findings
The official probable cause findings from the investigation identified several causation factors. According to the report, the pilot continued VFR flight into instrument meteorological conditions (IMC). Additionally, the pilot made improper use of flight controls, lacked total instrument time, and experienced spatial disorientation. The aircraft's design stress limits were exceeded, which led to wing overload, failure, and complete separation. Other contributing factors included inadequate preflight planning and the pilot not obtaining in-flight weather advisories as recommended.