Aug 5, 1998
Accident
Substantial JACKSON, CA
InjuriesNone
Phase of Flight-
ConditionsVMC
OperationFAR 091
Probable Cause
Failure of the propeller governor pulley drive shaft due to a modification made to the system by the owner that included welding a retaining pin to the center of the heat treated drive shaft, which compromised the shaft's design strength margin.
NTSB LAX98LA258