Incident Description
Shortly after takeoff, the right engine of the airplane lost power. Subsequently, the right wing lowered to approximately 90 degrees, and the airplane impacted the ground adjacent to the runway. The ground loader who had fueled the airplane from the airport fuel truck stated that the flight crew did not sump the fuel tanks after fueling.
Fuel Contamination
Examination of the forward fuel tank, which supplies fuel to the right engine, revealed about 8 gallons of a heavily contaminated mixture. The contamination consisted of water, an emulsifying agent, and bacterial growth. The fuel from the airport fuel truck and the main underground tank contained the same mixture. Fuel had been transferred from the underground tank to the truck on the evening before the accident.
Propeller Control Findings
The left propeller control was found seized in the feather position, and the left propeller blades were in the near feather position.
Injuries and Fatalities
Six skydivers sustained injuries, while 16 other occupants, including both pilots, were killed.
Probable Cause
The official probable cause of the accident was the pilot-in-command's inadvertent feathering of the wrong propeller following an engine power loss, and the failure of the operator to assure that the pilot was provided with adequate training in the airplane. Factors related to the accident were: water contamination of fuel in the airport storage tanks, the operator's lack of fuel quality control procedures, improper fuel servicing, improper preflight by the pilot(s), and exceeding the gross weight/forward cg limits of the airplane.