Weather Briefing
The pilot was briefed that thunderstorms were developing along his planned route of flight and were forecast to become "severe." He also received a hazardous weather information alert (HIWAS) indicating hail, wind gusts up to 70 knots, and cloud tops at 55,000 feet.
Communications
The pilot contacted ATC and expressed concern about the weather on his route. ATC cleared him to deviate around the weather. While deviating, the pilot stated, "...I'm into a cell here I think I need to get down...Bonanza one zero two alpha I need to go down." He was cleared to descend to 5,000 feet. One minute and two seconds after that clearance, the pilot said, "I'm in a pretty bad cell I need help, over." Radar and radio communication with the flight were lost and never reestablished. The last recorded radar return showed the airplane at an altitude of 6,700 feet, heading in a northeasterly direction.
Witness Account
A witness reported hearing an airplane "in a steep descent, straight down dive," and the engine running until he heard a "loud boom." The witness described the weather at the time as "lightning, thunder, and strong winds."
Weather Study and Damage
The left wing and tail stabilizer had separated from the airframe prior to impact. A weather study revealed that at the time of the accident, the airplane had progressed into an area of strong thunderstorm activity with cloud tops of about 42,000 to 43,000 feet. A level three to level four thunderstorm was within 0.25 nautical mile of the flight, and a level four thunderstorm was within 0.5 nautical mile. Additionally, the thunderstorms contained intense to extreme precipitation, severe to extreme turbulence, and hail.