Background
The private pilot, who reported approximately 3,000 hours of flight time, departed from his home base at Thermal, California, for a short cross-country flight to Las Vegas, Nevada. The pilot did not possess an instrument rating. No record of a preflight weather briefing exists, and no flight plan was filed.
Flight and Search
After the pilot failed to arrive at the destination, a search was initiated. The wreckage was located six days after departure, aided by radar data. According to radar information, the airplane was at an altitude of 16,100 feet when it began a series of maneuvers while descending.
Wreckage and Weather
Postcrash examination revealed that the left wing outer panel, aileron, and left engine were found some distance from the main wreckage, indicating an in-flight breakup. The weather at the time was reported as marginal visual flight rules (VFR) with thunderstorm cell activity in the area. The airplane was not equipped with a working oxygen system, nor was it configured for instrument flight or icing conditions.
Probable Cause
The official probable cause is the pilot's inadvertent flight into instrument meteorological conditions (IMC). Contributing factors include loss of control and exceeding the structural limits of the aircraft, with weather conditions also cited as factors.