What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
The pilot was conducting tree trimming operations on a power line right of way utilizing a 10 bladed aerial saw that slung below the helicopter. During the cutting, a saw blade snagged a steel braided logging cable that wrapped itself around the lower saw blades. A section of the cable broke off and struck the tail rotor assembly damaging the stabilizers and tail rotor pitch control bellcrank mounting flange resulting in a rapid uncontrolled yaw. The helicopter impacted trees and came to rest on its left side. The impact resulted in substantial damage to the airframe and rotor blades. Continuity of the tail rotor pitch control and drivetrain system was established. There were no pre accident mechanical failures or malfunctions that would have precluded normal operation.
As the FAA filed it
THE PILOT WAS CONDUCTING TREE TRIMMING OPERATIONS ON A POWER LINE RIGHT OF WAY UTILIZING A 10 BLADED AERIAL SAW THAT SLUNG BELOW THE HELICOPTER. DURING THE CUTTING, A SAW BLADE SNAGGED A STEEL BRAIDED LOGGING CABLE THAT WRAPPED ITSELF AROUND THE LOWER SAW BLADES. A SECTION OF THE CABLE BROKE OFF AND STRUCK THE TAIL ROTOR ASSEMBLY DAMAGING THE STABILIZERS AND TAIL ROTOR PITCH CONTROL BELLCRANK MOUNTING FLANGE RESULTING IN A RAPID UNCONTROLLED YAW. THE HELICOPTER IMPACTED TREES AND CAME TO REST ON ITS LEFT SIDE. THE IMPACT RESULTED IN SUBSTANTIAL DAMAGE TO THE AIRFRAME AND ROTOR BLADES. CONTINUITY OF THE TAIL ROTOR PITCH CONTROL AND DRIVETRAIN SYSTEM WAS ESTABLISHED. THERE WERE NO PRE ACCIDENT MECHANICAL FAILURES OR MALFUNCTIONS THAT WOULD HAVE PRECLUDED NORMAL OPERATION.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.
Other reports on N11AS · 1
Matched to the same aircraft by N-number and date.