NTSB Probable Cause

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.