N629JK

HISTORY OF FLIGHTOn May 4, 2016, at 1002 central daylight time, an MD Helicopters 369E helicopter, N629JK, impacted trees and terrain near Reedsville, Wisconsin. The commercial-rated pilot, who was the sole occupant, was fatally injured, and the helicopter sustained substantial damage. The helicopter was registered to Padgett Ag Air, LLC, Pawleys Island, South Carolina, and operated by Rotor Blade, LLC Georgetown, South Carolina, under the provisions of 14 Code of Federal Regulations (CFR) Part 133 as an external load operation. Visual meteorological conditions prevailed at the time of the accident, and no flight plan was filed. The flight departed from the Manitowoc County Airport (MTW), Manitowoc, Wisconsin, about 0730.

The helicopter was being used to transport personnel and equipment in support of a power line construction project to replace a shield wire with a fiber optic cable. The project began on March 10, 2016, with a basic helicopter and landing zone (LZ) safety course provided by Rotor Blade for the construction employees. The project had continued without interruption except for weather delays. On the morning of the accident, the helicopter arrived at the LZ about 0800. Two job briefings were conducted, and the helicopter was to transport linemen, equipment, and materials to various power line tower structures that were about 125 ft tall using a 50 ft long line attached to the cargo hook. The helicopter flew from 0842 to 0906 and then returned to the LZ.

At 0949, the helicopter departed the LZ and transported two linemen from tower 9903 to the neighboring tower, 9904 (figure 1). When the linemen detached from the long line, the helicopter proceeded to the east and hovered for 2 to 3 minutes. The linemen requested that the helicopter come back to tower 9904 to pick up equipment and return to the LZ. The helicopter approached the tower from the southwest and faced northeast into the wind as the linemen presented hand signals to the pilot. The linemen stated that the end of the long line was about 20 ft laterally and 15 ft vertically from their reach when they noticed the helicopter's sound change and it descended suddenly. The helicopter veered to the right away from the tower, and the main rotor blades slowed noticeably. The helicopter continued into the trees and terrain south of the tower. The linemen climbed down from the tower and heard the helicopter's engine still producing noise. One lineman pulled the emergency fuel shutoff valve and turned off the battery.

Figure 1 – Google Earth overview of the accident area with GPS track downloaded from Garmin 496 onboard helicopter

Two other project employees were about 150 yards north of tower 9904 (figure 2); they stated that, as the helicopter approached tower 9904 for the final time, the main rotor blades slowed down, the engine sound decreased, and the helicopter veered right toward the ground.

Figure 2 – View from project employee witness location, facing south toward tower 9904 PERSONNEL INFORMATIONThe pilot's logbooks were not found during the course of the investigation. Company flight log reports revealed that the pilot flew the accident helicopter from March 8 to May 3, 2016, for a total of 67 hours. The pilot also flew the accident helicopter for an estimated 2.5 hours on the morning of the accident. AIRCRAFT INFORMATIONThe MD 369E features a fully articulated five-bladed main rotor system with anti-torque provided by a four-bladed semi-rigid tail rotor. The helicopter was configured to be flown from the left pilot seat (figure 3).

Figure 3 – Preaccident photograph of the helicopter

The helicopter had accumulated 7,688.4 hours total time (TT) at the time of the accident. A review of the maintenance records revealed an annual inspection was completed on December 4, 2015, at 7,522.6 hours TT. At the time of the accident, the engine, a Roll-Royce 250-C20B, had accumulated 1,048.7 hours TT since new. On April 3, 2016, at 987.4 hours engine TT, a 150-hour engine inspection was completed, and a fuel control tube was replaced. Also replaced during the maintenance work were the engine combustion case, combustion liner, and engine bleed valve due to a power transient over-temperature of 850°C for 2 seconds.

On April 16, 2016, an inoperative power turbine speed (N2) dual tachometer was replaced. On April 26, 2016, a video was taken of the dual tachometer as the helicopter was in flight, and it showed that the dual tachometer indicated about 475 rotor rpm and about 60% N2 rpm. The Rotor Blade ground crewman who took the video stated that the pilot wanted him to send the video to a Rotor Blade mechanic to show him that there was still an issue with the dual tachometer. The Rotor Blade mechanic stated that he watched the video, but it was not sent directly to him. He stated that he told the pilot not to fly the helicopter if there was a problem. The mechanic and the pilot discussed that it was likely only an indicating issue.

The engine was installed new on the helicopter on November 21, 2007. The engine's accessories, including power turbine governor (PTG) model AL-AA2, part number 2549170-1, serial number HR48214, were installed new with 0.0 hours TT. No records indicated any maintenance completed on the PTG after initial installation. The records revealed that all applicable Federal Aviation Administration (FAA) Airworthiness Directives had been completed.

Weight and balance calculations for the helicopter revealed that the center of gravity was within limits, the gross weight at the time of the accident was 2,097 lbs, and the maximum gross weight was 3,550 lbs.

The operator was authorized by the FAA to conduct class A, B, and C external load operations. The helicopter was equipped with an Onboard Systems hydraulic hook kit and Rotor Blade, LLC, H500 side hook assembly.

On May 3, 2016, the company fuel truck was fueled with 211.3 gallons of Jet-A at MTW. The fuel logs revealed that, before the 0800 departure from the LZ, the helicopter was refueled at the fuel truck and departed with 260 lbs of fuel. Before the final departure at 0949, the helicopter was refueled and departed with 240 lbs (35.29 gallons) of fuel, which was estimated to provide 1 hour 10 minutes of flight time. AIRPORT INFORMATIONThe MD 369E features a fully articulated five-bladed main rotor system with anti-torque provided by a four-bladed semi-rigid tail rotor. The helicopter was configured to be flown from the left pilot seat (figure 3).

Figure 3 – Preaccident photograph of the helicopter

The helicopter had accumulated 7,688.4 hours total time (TT) at the time of the accident. A review of the maintenance records revealed an annual inspection was completed on December 4, 2015, at 7,522.6 hours TT. At the time of the accident, the engine, a Roll-Royce 250-C20B, had accumulated 1,048.7 hours TT since new. On April 3, 2016, at 987.4 hours engine TT, a 150-hour engine inspection was completed, and a fuel control tube was replaced. Also replaced during the maintenance work were the engine combustion case, combustion liner, and engine bleed valve due to a power transient over-temperature of 850°C for 2 seconds.

On April 16, 2016, an inoperative power turbine speed (N2) dual tachometer was replaced. On April 26, 2016, a video was taken of the dual tachometer as the helicopter was in flight, and it showed that the dual tachometer indicated about 475 rotor rpm and about 60% N2 rpm. The Rotor Blade ground crewman who took the video stated that the pilot wanted him to send the video to a Rotor Blade mechanic to show him that there was still an issue with the dual tachometer. The Rotor Blade mechanic stated that he watched the video, but it was not sent directly to him. He stated that he told the pilot not to fly the helicopter if there was a problem. The mechanic and the pilot discussed that it was likely only an indicating issue.

The engine was installed new on the helicopter on November 21, 2007. The engine's accessories, including power turbine governor (PTG) model AL-AA2, part number 2549170-1, serial number HR48214, were installed new with 0.0 hours TT. No records indicated any maintenance completed on the PTG after initial installation. The records revealed that all applicable Federal Aviation Administration (FAA) Airworthiness Directives had been completed.

Weight and balance calculations for the helicopter revealed that the center of gravity was within limits, the gross weight at the time of the accident was 2,097 lbs, and the maximum gross weight was 3,550 lbs.

The operator was authorized by the FAA to conduct class A, B, and C external load operations. The helicopter was equipped with an Onboard Systems hydraulic hook kit and Rotor Blade, LLC, H500 side hook assembly.

On May 3, 2016, the company fuel truck was fueled with 211.3 gallons of Jet-A at MTW. The fuel logs revealed that, before the 0800 departure from the LZ, the helicopter was refueled at the fuel truck and departed with 260 lbs of fuel. Before the final departure at 0949, the helicopter was refueled and departed with 240 lbs (35.29 gallons) of fuel, which was estimated to provide 1 hour 10 minutes of flight time. WRECKAGE AND IMPACT INFORMATIONThe helicopter came to rest in a wooded area about 125 ft south of tower 9904 (figure 4/5). The surrounding trees were 50 to 75 ft tall, and several of them were broken or showed signs of recent scaring and damage, consistent with the helicopter's impact sequence. All of the major components of the helicopter were found at the accident site. The long line remained attached to the cargo hook and trailed north toward the tower. There was an odor of Jet-A fuel around the main wreckage, and fuel was observed leaking from the helicopter. On-scene documentation was completed, and the wreckage was recovered to a secure examination facility.

Figure 4 – The accident helicopter surrounded by trees

Figure 5 – Front view of accident helicopter damage

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