Aug 1, 2012
Accident
Substantial Middletown, DE
InjuriesNone
Phase of Flight-
ConditionsVMC
OperationFAR 133
Probable Cause
The pilot's failure to recognize that the helicopter was experiencing tail rotor dynamic instability and to take immediate corrective actions during an external load lift, which resulted in the failure of a tail rotor blade.
NTSB ERA12LA493