Helicopter Impacted And Severed An Energized Wire, Also Known As A “Primary Wire”

Location: Wingate, NC Accident Number: ERA21FA200
Date & Time: May 2, 2021, 13:18 Local Registration: N4528T
Aircraft: ROBINSON HELICOPTER R44 Injuries: 1 Fatal
Flight Conducted Under: Part 137: Agricultural

On May 2, 2021, at 1318 eastern daylight time, a Robinson R-44 helicopter, N4528T, was substantially damaged when it was involved in an accident near Wingate, North Carolina. The pilot was fatally injured. The helicopter was being operated as a Title 14 Code of Federal Regulations Part 137 aerial application flight.

The commercial pilot was spraying fungicide on a wheat field when the accident occurred. According to several witnesses, this was the first time they had observed the northwest portion of the field, which contained multiple power lines, being sprayed via aerial application. The helicopter had been applying fungicide all morning, operating about 15 ft above the 3-ft-tall wheat during the spraying operation. The pilot’s wife reported that after landing, having lunch and loading more fungicide, the pilot took off to begin spraying where he left off. Images recovered from a GPS application on the pilot’s tablet computer showed that the helicopter took off, flew to where the pilot left off, and completed its first pass in a northerly heading. The helicopter then turned and flew over the field on a southerly heading. The data correlated to the helicopter’s flight track ended in the vicinity of where the helicopter’s main wreckage came to rest.

Witnesses in a nearby home reported that they heard a loud noise and simultaneously lost electricity to their home. They then looked out their window and saw the helicopter as it descended in a nose-down attitude before it impacted the field in the vicinity of the power lines. One of the witnesses stated that it appeared as though the helicopter became entangled in the wires before it descended nose-first into the ground.

The helicopter impacted and severed an energized wire, also known as a “primary wire” that was oriented about 228° magnetic and measured about 29 ft above ground level at its lowest point over the wheat field. The wire spanned about 345 ft between two utility poles, 264 ft of that span over the wheat field. Two additional power lines spanned other portions of this northwesterly portion of the field.

The helicopter came to rest on its left side. The fuselage was crushed and deformed aft. The tail boom remained attached to the main fuselage; however, the empennage, composed of the upper and lower vertical stabilizers, horizontal stabilizer, the tail rotor and its gearbox, were separated from the tail boom. The windscreen and door windows were separated from the fuselage and fragmented. Both main rotor blades remained attached to the hub and were whole from root to tip. One blade was bent downwards about 2 ft outboard of the blade grip, and the other was bent downward and in a U-shape. The agricultural hopper remained partially attached to the fuselage. It was breached and its lower side was crush-damaged. The engine compartment and engine remained intact.

The empennage was located 99 ft and 336° from the main wreckage. The lower vertical stabilizer sustained trailing edge impact and semi-circular crush damage just below the horizontal stabilizer. The tail rotor gearbox was intact but separated from its airframe mount and was located about 112 ft and 208° from the main wreckage. The tail rotor  hub remained attached to the tail rotor gearbox output shaft and portions of the two tail rotor blades remained attached to the hub. One tail rotor blade was missing about 5 inches of its tip end and the other tail rotor blade was missing about 2 ft of its outboard span. One of these sections was not recovered. The leading edges of both tail rotor blades exhibited impact damage. A fractured segment of one of the tail rotor blades, measuring about 18 inches in length, was located 170 ft and 44° from the main wreckage. The tip portion of one of the fractured tail rotor blades, measuring about 5 inches, was located 119 ft and 3° from the main wreckage. The tip portion exhibited impact scars consistent with a wire strike as well as impact with the tail rotor guard.

Charlotte-Monroe Executive Airport (EQY) was located about 12 miles northwest of the accident site. At 1253, the reported weather included scattered clouds at 3,800 ft. A review of astronomical data from the National Oceanic and Atmospheric Administration revealed that at the time of the accident, the sun was located at an azimuth of about 180° and an elevation of about 71°. The wreckage was retained for further examination.

FMI: www.ntsb.gov