Flight History
On February 27, 2017, about 1033 central standard time, a Bell 407 helicopter, registration N1371, was destroyed when it impacted marshy water approximately 15 miles southwest of Houma, Louisiana (HUM). The commercial pilot was fatally injured. The flight was a repositioning flight operated by Westwind Helicopters under 14 CFR Part 91. Visual meteorological conditions prevailed, and a company flight plan was activated. The flight originated at 1014 from offshore oil platform South Timbalier ST37 in the Gulf of Mexico.
Before the accident flight, the helicopter had completed a 14 CFR Part 135 passenger flight from HUM to ST37, dropping off two passengers. The passengers reported that the flight to ST37 was normal. According to the operator, the pilot was to return the helicopter to HUM for a minor repair of an engine cowling fastener. The pilot was the only person onboard for the approximate 30-minute flight to HUM.
The helicopter was equipped with an on-board flight tracking system (Sky Connect). After takeoff from ST37, six flight path data points were recorded at 2-minute intervals. The data showed the helicopter on a northwest heading, with ground speeds between 144 and 150 knots. The last data point, at 1024, indicated an altitude of 374 feet and ground speed of 148 knots. Sky Connect issued an "Overdue" alarm at 1033. At 1103, company flight monitoring personnel dispatched a search helicopter, and the wreckage was found at 1135 about 15 miles south-southeast of HUM.
There were no reported witnesses to the accident. No radio or distress calls were heard from the helicopter, and the Sky Connect emergency button was not activated.
Personnel Information
The pilot held a commercial pilot certificate with rotorcraft-helicopter and instrument ratings. He was hired by Westwind Helicopters on July 17, 2016. His total flight time as of the accident was 2,266 hours, all in light helicopters, with 120 hours in the accident helicopter make and model. He had flown 140 flight hours in single-engine helicopters in the 90 days before the accident. According to training records, the pilot was current and qualified in offshore Part 135 flight operations. His most recent FAA second-class medical certificate was issued in June 2016 with no limitations.
Aircraft Information
Westwind Helicopters leased the helicopter (serial number 53182) from GM Leasing in April 2015. It had a total airframe time of 9,146.8 hours at the time of the accident. The helicopter was equipped with an Allison 250C47B turbo shaft engine (serial number CAE847222) with a total time of 15,510.6 hours. The most recent 100-hour inspection was completed on February 16, 2017, at 9,125.5 airframe hours. Maintenance records indicated compliance with all required scheduled inspections and no uncorrected maintenance actions.
Meteorological Information
At 0950, the weather observation at HUM included wind from 150° at 12 knots gusting to 17 knots, visibility 5 statute miles with haze, scattered clouds at 1,000 feet, a broken ceiling at 2,200 feet, temperature 24°C, dew point 21°C, and an altimeter setting of 30.12 inches of mercury. The search pilot reported conditions at the accident site around 1130 included 5-7 miles visibility with ceilings above 700 feet.
Wreckage and Impact Information
The wreckage was found in shallow marsh waters south of Timbalier Bay, about 15 miles south-southeast of HUM. The airframe was destroyed by impact forces upon water contact, breaking into several pieces. The left forward Dzus fastener on the engine cowling that was reported loose was missing, and the cowling mounting hole was fractured. The skid-mounted float system was not deployed. Detailed examinations of the recovered components were conducted, involving the NTSB, FAA, Westwind Helicopters, Rolls Royce, and Bell Helicopter.
Examinations of the main and tail rotor systems, flight controls, hydraulics, drive system, fuel system, and engine revealed no pre-impact anomalies. The engine had been submerged in salt water for about 3 days before examination. The ECU data extraction showed no faults with the engine. The operator reported that normal airspeed for a return flight from offshore is about 120 knots, while Sky Connect data showed ground speeds between 144 and 148 knots.
Medical and Pathological Information
The Terrebonne Medical Examiner's Office performed an autopsy on February 28, 2017, determining the cause of death as blunt trauma. Toxicological testing by the FAA found no drugs, ethanol, or carbon monoxide.
Additional Information
After the accident, the operator implemented a Flight Operational Quality Assurance (FOQA) program to install Flight Data Management equipment in all company aircraft to capture flight data, cockpit audio, and imagery on all flights.