Accident Overview
A Sherpa aircraft operating as flight PAT528 departed Hurlburt Field Air Force Base, Florida, en route to Oceana Naval Air Station, Virginia. The aircraft carried 18 passengers and a crew of three. While cruising over Georgia, the crew encountered poor weather conditions including thunderstorm activity, heavy rainfall, severe turbulence, windshear, and wind gusts up to 72 knots. The aircraft became unstable, losing 100 feet of altitude in three seconds before adopting a nose-up attitude. Over the next 12 seconds, the aircraft experienced a positive aerodynamic acceleration, then entered an uncontrolled descent. It partially disintegrated in the air and eventually crashed in an open field. All 21 occupants were killed.
Crew and Passengers
The crew, assigned to the 171st Aviation Regiment in Lakeland, consisted of Chief Warrant Officer 4 Johnny W. Duce, Chief Warrant Officer 2 Erik P. Larson, and Staff Sergeant Robert F. Ward Jr. The passengers were from the 213th Red Horse Flight in Virginia Beach: Master Sergeant James Beninati, Staff Sergeant Paul J. Blancato, Technical Sergeant Ernest Blawas, Staff Sergeant Andrew H. Bridges, Master Sergeant Eric G. Bulman, Staff Sergeant Paul E. Cramer, Technical Sergeant Michael E. East, Staff Sergeant Ronald L. Elkin, Staff Sergeant James P. Ferguson, Staff Sergeant Randy V. Johnson, Senior Airman Matthew K. Kidd, Master Sergeant Michael E. Lane, Technical Sergeant Edwin B. Richardson, Technical Sergeant Dean J. Shelby, Staff Sergeant John L. Sincavage, Staff Sergeant Gregory T. Skurupey, Staff Sergeant Richard L. Summerell, and Major Frederick V. Watkins III.
Probable Cause
The Collateral Investigation Board determined that the preponderance of evidence concluded the accident was due to crew error. The board found other factors present but not contributing directly. Specifically, the board found that the crew failed to properly load the aircraft, leading to a failure to manage weight and balance. This resulted in an out-of-center-of-gravity (CG) condition that exceeded the aircraft's design limits, rendering the aircraft unstable and causing a violent departure from controlled flight. Once control was lost, rapid onset of significant G-force shifts incapacitated the crew and passengers, leading to structural breakup in flight and eventual ground impact.