20180408000149A

On April 8, 2018, at approximately 6:03 pm EDT, a macdonald Douglas helicopter MD600N, N602BP, operated by high line helicopters, LLC, was destroyed when it collided with a wooden power line pole that was located in Smethport, PA. The commercial pilot sustained serious injuries in the crash, and the two lineman were fatally injured. The weather at the time of the accident was visual meteorological conditions (VMC). The power line flight was conducted under 14 CFR part 133 external load operation.

The helicopter crew was working on a static line that was located on pole #15884. The lines were running east and west in a heavily wooded area. The poles are installed in an h-frame configuration, consisting of wood and steel. The lineman were in the process of installing the armor rod to the static line that was resting in the dolly block attached to the pole. The purpose of the flight was to remove the static line from the dolly and permanently attach it to the pole. There were two lineman onboard; one of the lineman was sitting in the back of the helicopter assisting the second lineman that was standing on the skid conducting the work on the pole.

The lineman working in the back of the helicopter were conducting a routine task of attaching the armor rod (spiral wire covering) to the static line. The second step in the process is to attach the safety strap to the top on the pole. The third step is to attach the chain hoist to the static line, hoist the line up to the top of the pole, and bolt it to the structure. The safety strap, chain hoist and dolly would be removed after the static line is permanently attached.

In an interview, the pilot reported that the entire crew met earlier in the day, and flew to a structure to assess the work and tools required to complete the assigned task. They landed, refueled, and departed on the accident flight. The crew completed one structure, and the pilot hovered the helicopter into position to complete the work on the next structure. The lineman attached the first half of the armor rod ahead of the dolly, and manipulated the line and the dolly to complete the wrap. According to the pilot, the lineman opened the spring-loaded locking gate on the dolly above the static line to wrap the second half of the armor rod, which was "normal," and prior to the attachment of the safety. About that time, the pilot felt the helicopter was "pulled" toward the structure. He made cyclic and pedal inputs to avoid the structure, but "all I remember is rolling over the structure." When asked, the pilot said he neither felt nor heard anything unusual prior to the helicopter being pulled to the structure.

The helicopter came to rest below the southern pole. The helicopters tail boom and rotor blades separated during the roll/descent over the h-frame structure. The rotor blades were located as FAR as 500 to 600 feet from the wreckage. The majority of the wreckage came to rest at the bottom of the southern pole. The left skid forward of the front crosstube showed striating marks consistent with wire contact on the top of the tube.

Upon examination of the wreckage and structure, the safety strap was found hanging from the cross brace of the h-frame that was struck by the helicopter. The chain hoist was found at the bottom of the southern pole and was undamaged. The dolly that was attached to the pole was recovered and examined. The examination showed that the dolly-locking gate was damaged. The helicopter cross-tube also showed evidence of orange paint from the dolly?s safety guard.

The pilot was a commercially rated pilot with ratings for rotorcraft-helicopter and instrument helicopter. The pilot had a current second-class medical with a date of April 5, 2017. The operator reports that the pilot has approximately 6,200 hours of flight time and 250 hours in the MD600N. The operator stated that the pilot had approximately 3,000 hours of power line operations.