What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
The pilot was following a canal applying herbicide. A low set of power lines paralleled the canal and the pilot was focused on avoiding those wires. The aircraft entered a larger set of transmission lines suspended above the flight path. The aircraft contacted the upper static wire and became entangled in the two lower two inch power conductor lines below during the accident sequence. The pilot stated he attempted to roll the aircraft to cut through wires and stop the rotation of the helicopter.
The on scene examination of the helicopter showed striation marks from the static wire wrapping around the static mast of the helicopter. The marks were pronounced in a deep area crushed around the circumference of the static mast. The tail boom was folded at mid span with a deep indention through the tail boom with a circular depression consistent with the diameter to one of the conductor wires. The main rotor blades displayed striation marks from the static wire on the lower surface.
The ops poi asked the pilot about the method he used to survey his work area prior to the application. The pilot stated he flew this section of the work area prior to the accident.
As the FAA filed it
THE PILOT WAS FOLLOWING A CANAL APPLYING HERBICIDE. A LOW SET OF POWER LINES PARALLELED THE CANAL AND THE PILOT WAS FOCUSED ON AVOIDING THOSE WIRES. THE AIRCRAFT ENTERED A LARGER SET OF TRANSMISSION LINES SUSPENDED ABOVE THE FLIGHT PATH. THE AIRCRAFT CONTACTED THE UPPER STATIC WIRE AND BECAME ENTANGLED IN THE TWO LOWER TWO INCH POWER CONDUCTOR LINES BELOW DURING THE ACCIDENT SEQUENCE. THE PILOT STATED HE ATTEMPTED TO ROLL THE AIRCRAFT TO CUT THROUGH WIRES AND STOP THE ROTATION OF THE HELICOPTER.
THE ON SCENE EXAMINATION OF THE HELICOPTER SHOWED STRIATION MARKS FROM THE STATIC WIRE WRAPPING AROUND THE STATIC MAST OF THE HELICOPTER. THE MARKS WERE PRONOUNCED IN A DEEP AREA CRUSHED AROUND THE CIRCUMFERENCE OF THE STATIC MAST. THE TAIL BOOM WAS FOLDED AT MID SPAN WITH A DEEP INDENTION THROUGH THE TAIL BOOM WITH A CIRCULAR DEPRESSION CONSISTENT WITH THE DIAMETER TO ONE OF THE CONDUCTOR WIRES. THE MAIN ROTOR BLADES DISPLAYED STRIATION MARKS FROM THE STATIC WIRE ON THE LOWER SURFACE.
THE OPS POI ASKED THE PILOT ABOUT THE METHOD HE USED TO SURVEY HIS WORK AREA PRIOR TO THE APPLICATION. THE PILOT STATED HE FLEW THIS SECTION OF THE WORK AREA PRIOR TO THE ACCIDENT.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.