N910SAmerican Eurocopter AS350B3 · 2012

On October 29, 2018, about 1345 central daylight time, a Eurocopter (Airbus) AS350 B3 helicopter, N910S, impacted terrain near Odanah, Wisconsin. The pilot was fatally injured, and the helicopter was destroyed. The helicopter was registered to and operated by Enbridge Energy Company, Inc., as a Title 14 Code of Federal Regulations Part 91 aerial observation fight. Visual meteorological conditions prevailed at the time of the accident. The flight departed Gogebic-Iron County Airport (IWD), Ironwood, Michigan, about 1300 and was en route to Madison, Wisconsin.

The flight was scheduled as a routine pipeline patrol flight. Two pipeline employees who were working on the pipeline about 2 to 3 miles from the accident site reported seeing the helicopter flying overhead. One of the employees, who had seen pipeline helicopters flying overhead numerous times, stated that he saw "nothing unusual about the helicopter" and heard "no unusual sounds coming from the helicopter."

When the pilot did not arrive at his intended destination, an alert notice was issued for the overdue helicopter. The pilot had not been in contact with air traffic control during the flight, and there was no record of a distress call from the pilot.The helicopter wreckage was subsequently located about 22 miles west of IWD in a remote wooded area and about 200 yards north of the east-west pipeline.

The pilot was a Canadian citizen and held a Canadian commercial pilot certificate with helicopter and instrument ratings. He also held a Canadian private pilot certificate with airplane single-engine land and instrument ratings and a US private pilot certificate with a rotorcraft-helicopter rating (based on the pilot's Canadian license). The pilot held a Canadian category 1 medical certificate. His last medical exam was conducted on October 1 2018; however, the last medical exam and certificate on file with Transport Canada was dated March 12, 2018.

The operator reported that the pilot had 16,894 hours of total flight experience with 16,535 hours in helicopters, 693 hours of which were in the AS350. The pilot had flown 208 hours in the AS350 during the preceding 90 days before the accident.

The helicopter, a Eurocopter AS350 B3 (present designation: Airbus H125), had a three-bladed main rotor system that rotated in a clockwise direction, with the three main rotor blades attached to a Starflex rotor head. The helicopter was powered by a (Safran) Turbomeca Arriel 2D turboshaft engine. Although the helicopter was equipped with a long-range fuel cell, it was not connected to the helicopter's fuel system. The helicopter received 120 gallons of fuel before departing IWD. The helicopter was also equipped with an Appareo Vision 1000 cockpit image and flight data monitoring system.

The helicopter was maintained under the manufacturer's maintenance inspection program. A review of the maintenance records revealed the helicopter's last inspection was completed on October 26, 2018, with a total airframe time of 2,965.7 hours. At the time of the inspection, the engine had accumulated 2,965.2 total hours and 1,483 cycles.

At 1356, the automated weather observing system at IWD recorded wind from 300° at 6 knots, 10 miles visibility, overcast sky at 1,600 ft, temperature 41°F, dew point 36°F, and altimeter setting 30.02 inches of mercury.

The helicopter, a Eurocopter AS350 B3 (present designation: Airbus H125), had a three-bladed main rotor system that rotated in a clockwise direction, with the three main rotor blades attached to a Starflex rotor head. The helicopter was powered by a (Safran) Turbomeca Arriel 2D turboshaft engine. Although the helicopter was equipped with a long-range fuel cell, it was not connected to the helicopter's fuel system. The helicopter received 120 gallons of fuel before departing IWD. The helicopter was also equipped with an Appareo Vision 1000 cockpit image and flight data monitoring system.

The helicopter was maintained under the manufacturer's maintenance inspection program. A review of the maintenance records revealed the helicopter's last inspection was completed on October 26, 2018, with a total airframe time of 2,965.7 hours. At the time of the inspection, the engine had accumulated 2,965.2 total hours and 1,483 cycles.

The helicopter impacted trees and terrain before it came to rest in an upright position within the trees. Several trees at the crash site showed cuts, and one tree with a diameter of about 10 to 12 inches was completely severed in half. Except for small fragments of plexiglass, the helicopter wreckage was confined to the impact/resting site.The front of the cabin and the cockpit area were mostly destroyed by impact forces and a post-crash fire. The major helicopter components were located at the accident site.

The helicopter was examined on scene by the NTSB investigator-in-charge, and technical representatives from the engine and airframe manufacturers. The flight control continuity inspection was limited due to fire damage, but the bolt connections to the actuators were confirmed. The tail rotor pitch control moved freely: the tail rotor flex cable was attached and ran forward and under the fire-damaged cabin floor. The cyclic and anti-torque pedals were connected to their respective tubes beneath the floor but were destroyed under the cabin area.

The helicopter's Appareo Vision system was located within the wreckage; however, the unit was badly fire damaged, and no data could be retrieved from the unit.

The engine received extensive fire and impact damage. The engine 's intake axial compressor blades exhibited damage near the outer tips, and the module 5 torque nut had a slippage of about 1/16 to 1/8 inch (2 to 4 millimeters), consistent with engine power at the time of impact. The digital engine control unit and engine data recorder were removed and sent to a laboratory for download. However, no data could be extracted from the units because they were badly fire damaged.

The tail rotor blades were broken but remained attached; paint transfer and impact scars were consistent with the tail rotor blades impacting the stabilizer. The three main rotor blades remained with the wreckage and exhibited impact and fire damage.

Though the examination was limited by thermal and impact damage to the helicopter, no preimpact abnormalities were noted during the airframe or engine examinations.

An iPhone and iPad were recovered from the accident site and sent to the NTSB's Vehicle Recorder Division for download of non-volatile memory (NVM). Both units were damaged, and no information could be gleaned from the iPad. Information about text and e-mail messages, photographs, and telephone calls was found on the iPhone. Several photos were recovered from the iPhone that had been taken earlier in the day. The photos indicated the pilot photographed ground activity near the pipeline and of routine engine power checks,but none of the information was pertinent to the accident.

An autopsy on the pilot was performed by the Midwest Medical Examiner's Office, Ramsey, Minnesota. The pilot's cause of death was multiple blunt force injuries. The autopsy noted moderate to severe coronary artery diseasescarring of the heart muscle from a previous myocardial infarction (heart attack), and changes in the blood vessels of the liver that were indicative of congestive heart failure

Toxicology testing performed at the Federal Aviation Administration Forensic Sciences Laboratory was negative for carbon monoxide, ethanol and all tested drugs.