What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
While pulling powerline leader rope (sock line) from one pole to another power pole, aircraft struck top of pole with main rotor blades. Witness saw helicopter slowly sink onto the pole with slight counterclockwise yaw then saw helicopter main rotors strike the top of the pole, the tail rotor departed, aircraft then fell to the ground, came to rest below and near the pole. Second witness closet to the helicopter heard no change in engine noise or rotor noise until he heard the main rotor blades hit the pole and when he looked the helicopter was falling to the ground. Main rotor blade came through the right side of the aircraft cockpit. Main rotor blade cut the tail boom off.
As the FAA filed it
WHILE PULLING POWERLINE LEADER ROPE (SOCK LINE) FROM ONE POLE TO ANOTHER POWER POLE, AIRCRAFT STRUCK TOP OF POLE WITH MAIN ROTOR BLADES. WITNESS SAW HELICOPTER SLOWLY SINK ONTO THE POLE WITH SLIGHT COUNTERCLOCKWISE YAW THEN SAW HELICOPTER MAIN ROTORS STRIKE THE TOP OF THE POLE, THE TAIL ROTOR DEPARTED, AIRCRAFT THEN FELL TO THE GROUND, CAME TO REST BELOW AND NEAR THE POLE. SECOND WITNESS CLOSET TO THE HELICOPTER HEARD NO CHANGE IN ENGINE NOISE OR ROTOR NOISE UNTIL HE HEARD THE MAIN ROTOR BLADES HIT THE POLE AND WHEN HE LOOKED THE HELICOPTER WAS FALLING TO THE GROUND. MAIN ROTOR BLADE CAME THROUGH THE RIGHT SIDE OF THE AIRCRAFT COCKPIT. MAIN ROTOR BLADE CUT THE TAIL BOOM OFF.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.