Crashed and burst into flames in a farm field in heavy rain. All of the passengers were members of a Virginia-based military construction and engineering crew on a routine training mission. The plane’s pilot and two other crew members were members of the 171st Aviation Regiment of the Florida Army National Guard It appeared that the pilot’s decision to go to the bathroom shifted the weight of the already unbalanced plane and caused it to become unstable and uncontrollable while in an area of strong turbulence. The nose of the plane slowly pitched up and then abruptly dropped just before the crash. In three seconds, the plane rose more than 100 feet with its nose down, and was then rocked by wind shear three times greater than what is defined as extreme turbulence. Within the first 12 seconds that they encountered problems, the G-force shifts rendered the crew and passengers incapacitated and unconscious and caused the breakup of the aircraft in flight. It was also established that the weather radar was underpowered, negatively impacting the ability of the crew to successfully circumnavigate around the severe weather. This C-23B Sherpa was originally built as a Shorts 360 (SH-3684) in December 1985 and was delivered to Simmons Airlines as N374MQ In 1998 the aircraft was converted to a Sherpa C-23B+. PROBABLE CAUSE: “The Collateral Investigation Board found the preponderance of the evidence concluded that the aircraft accident was due to crew error. The board found other factors present but not contributing directly to this aircraft accident. These factors may have influenced the crew’s decision making process and aircraft performance. This is normally the case in most aircraft human factor accidents. The board did find the preponderance of the evidence directed the board toward the crew’s failure to properly load the aircraft. In particular, the crew’s failure to properly manage the weight and balance of the aircraft resulted in an ‘out-of-CG’ condition that exceeded the aircraft design limits, rendering the aircraft unstable and leading to a violent departure from controlled flight. Once the aircraft departed controlled flight, the rapid onset of significant G-force shifts rendered the crew and passengers incapacitated and unconscious and led to a structural break-up of the aircraft in flight. This ultimately resulted in the aircraft impacting the ground, killing all on board.”