11 Jun 2014: AIRBUS/EUROCOPTER AS 350 B3 — Can See Aviation LLC

11 Jun 2014: AIRBUS/EUROCOPTER AS 350 B3 (N356EV) — Can See Aviation LLC

No fatalities • Anchorage, AK, United States

Probable cause

The pilot’s improper engine start procedure, which resulted in an overspeed of the engine and main rotor drive system.

— NTSB Determination

Accident narrative

On June 11, 2014, about 1140 Alaska daylight time, an Airbus (formerly Eurocopter) AS350 B3 helicopter, N356EV, was substantially damaged when it was involved in an accident near Anchorage, Alaska. The helicopter was operated as a Title 14Code of Federal Regulations Part 91 personal flight. The first pilot, a certificated flight instructor, reported that he had been hired to ferry the recently-purchased helicopter to Georgetown, Texas. He added that he was providing AS350 B3 helicopter transition training to the second pilot, who was the new owner of the helicopter. The first pilot reported that, after two unsuccessful attempts to start the helicopter, he asked for assistance from a mechanic. The mechanic then contacted the operator’s rotor wing training manager to assist the first pilot in starting the helicopter. He said that while talking with the operator’s rotor wing training manager on a cell phone about the correct starting procedure, the second pilot exited the helicopter, and a mechanic boarded the helicopter and sat down in the right seat. Once the helicopter was successfully started, the mechanic disembarked, and the second pilot again boarded the helicopter, and sat down in the right seat. The first pilot noted that while the helicopter was operating at flight-idle, the yellow "TWT.GRIP" light was illuminated on the annunciator panel, and he instructed the second pilot to slowly advance the collective-mounted throttle twist grip to the open position until the light went out. He stated that, as the second pilot began to advance the throttle to the open position, the engine speed immediately increased to a very high rpm and the helicopter began to shake violently, and it subsequently rotated about 240° to the left. The pilot performed an emergency engine shutdown, and both pilots exited the helicopter. The helicopter's fuselage and main rotor drive system sustained substantial damage. The helicopter was equipped with a Turbomeca Arriel 2B-series turbine engine, with a single channel, full authority digital engine control (FADEC) fuel control system. The first pilot reported that he had extensive experience in various Airbus/Eurocopter helicopter models, which included about 6,000 flight hours in AS350 B2 helicopters, and about 2,000 flight hours in AS350 B3 helicopters (primarily equipped with the Turbomeca Arriel 2B1-series engine, which have a dual-channel FADEC). However, he could not recall how much experience he had in AS350 B3 helicopters equipped with the Turbomeca Arriel 2B-series engine. He thought he followed the engine start procedures in the helicopter’s flight manual.

The operator’s rotor wing training manager, who assisted the pilot in starting the helicopter, reported, in part: “I sensed when talking with the pilot that he did not have much experience, at least quality experience, with the AS 350 helicopter, especially the AS 350 B3…”

Airbus/Eurocopter Information Notice number 2169-I-67, dated June 6, 2010, specifically alerts operators to the different starting procedures for the AS350 B3 helicopters equipped with 2B-and 2B1-series engines.

A detailed wreckage and engine systems examination revealed no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operation. The accident helicopter’s hydro-mechanical metering unit (HMU), digital engine control unit (DECU), and the vehicle and engine multifunction display (VEMD) were removed and shipped to Turbomeca USA’s analytical facility in Grand Prairie, Texas.

The HMU was placed on a test stand, and it operated in accordance with the manufacture’s specifications. The VEMD and DECU were downloaded, which revealed no discernable fault codes of failures associated with the accident start sequence. The VEMD recorded a significant main rotor overspeed limit during the accident.

Contributing factors

  • Pilot
  • Pilot

Conditions

Weather
VMC, wind 000/04kt, vis 10sm

Loading the flight search…

What you can do on Flight Finder

  • Search flights between any two airports with live fares.
  • By aircraft — pick a plane model (e.g. Boeing 787, Airbus A350) and see every route it flies from your origin.
  • Route map — click any airport worldwide to explore its destinations, or draw a radius to find nearby airports.
  • Global aviation safety — aviation accident database, 5,200+ records since 1980, with map and rankings by aircraft and operator.
  • NTSB safety feed — recent U.S. aviation accidents and incidents from the official NTSB CAROL database, updated daily.

Frequently asked questions

How do I search flights by aircraft type on FlightFinder?

Pick an aircraft model — Boeing 737, Airbus A320, A380, Boeing 787 Dreamliner and more — enter your origin airport, and FlightFinder shows every route that plane flies from there with live fares.

Which aircraft types can I filter by?

We support Boeing 737/747/757/767/777/787, the full Airbus A220/A319/A320/A321/A330/A340/A350/A380 family, Embraer E170/E175/E190/E195, Bombardier CRJ and Dash 8, and the ATR 42/72 turboprops.

Is FlightFinder free to use?

Search and schedules are free. Pro ($4.99/month, $39/year, or $99 one-time lifetime) unlocks the enriched flight card — on-time stats, CO₂ per passenger, amenities, live gate & weather — plus My Trips with push alerts.

Where does the route data come from?

Live schedules come from Amadeus, AeroDataBox and Travelpayouts. Observed routes (which aircraft actually flew a given city pair) are crowdsourced from adsb.lol ADS-B data under the Open Database License.