Airbus Helicopters (Aerospatiale, Eurocopter) · Helicopter
Airbus AS355 Ecureuil 2 (TwinStar)
Is the Airbus AS355 Ecureuil 2 (TwinStar) safe? It ranks Shared rankWithin 1 point of other aircraft types: the difference is not meaningful.More in the glossary of 16 helicopters we rate, with 2 fatal accidents counted in about 370,000 US flights since 2008.
Likely range 47 to 75
How the score is built
- Fatal accidents
- 2 in 0.37 million flights
5.5 fatal accidents per million flights. Counted: all civil flights in the United States since 2008 (private, charter, air ambulance, utility, training and other), accidents and unexplained losses; not counted: accidents outside the United States or before 2008, military, test and illegal flights, sabotage, hijackings, shoot-downs and deliberate crew acts.
- Full-loss equivalents
- 1.5
Each counted accident adds the share of people on board who died (1 = no survivors). This is what the score is based on.
- Flights flown
- 0.37 million
Estimated flights of all kinds in the United States since 2008. Flights of all kinds in the United States (private, training, charter and other civil use) 2008 to 3 November 2026, each counted from take-off to final landing: the hours of all US twin-engine turbine helicopters in each year (active aircraft and hours from the FAA General Aviation and Part 135 Activity Survey), split between types by US-registered aircraft (FAA register, 33 of this type in 2024) times how much each type flies against its class (0.94, mostly from airframe hours in NTSB accident records, partly from hours per aircraft seen by ADS-B receivers in 2019-2022), at 0.77 hours per flight from ADS-B tracks: about 397 flights per registered aircraft per year in 2024. Flights and accidents outside the United States, or before 2008, are not used. Against the FAA's hours per helicopter model, this method is off by about 22% on a typical type. Uncertainty roughly ±20%.
- Technology generation
- Twin-engine turbine helicopter
Small fleets are pulled toward the record of the other types of their generation: 1.1 full-loss equivalents per million flights over 15.5 million flights. Weight of this family's own record: 38%.
- Likely range
- 47 to 75
The score is 90% likely to lie in this range, given how few accidents a type has and the error in the estimate of its flights.
- Last fatal accident
- 30 October 2018
Catalyst Aviation LLC, Beekmantown, NY, United States of America: 2 of 4 people on board died.
- Aircraft destroyed
- 2
Aircraft the NTSB coded as destroyed in an accident in the United States since 2008, fatal or not, from all causes. The NTSB codes many wrecks as only substantially damaged, so the real number is higher (context only, not in the score).
Compared with everyday risks
One flight on the Airbus AS355 Ecureuil 2 (TwinStar) carries about the same risk of death as the activities near it below.
- An hour's walk1 in 14 million
- Driving 100 miles (160 km)1 in 5.9 million
- An ordinary day: accidents and violence1 in 1 million
- A day of skiing1 in 830,000
- A scuba dive1 in 500,000
- One flight on the Airbus AS355 Ecureuil 2 (TwinStar)This aircraft1 in 450,000
- Cycling 100 miles (160 km)1 in 430,000
- Running a marathon1 in 290,000
- A skydive1 in 250,000
- A general anaesthetic1 in 100,000
- Riding a motorbike 100 miles (160 km)1 in 83,000
Accident history
2 fatal accidents in the United States since 2008 count toward the score, with 3 people on board killed.
| Date | Flight | Killed | What happened |
|---|---|---|---|
| Catalyst Aviation LLCEurocopter AS355F2 · Beekmantown, NY, United States of America | 2 killed / 4 on board | Hovering next to a utility pole near East Beekmantown, New York, so a lineman on an outside bench could fit a pulley, the AS355F2's skid hit the pole in a tailwind; it rolled over into live power lines and fell. The pilot and that lineman died.Type: Flight into terrainNTSB docket | |
| Analar CorporationEurocopter AS355F1 · West Windsor, NJ, United States of America | 1 killed / 1 on board | Cruising near Quakerbridge Mall, West Windsor, New Jersey, the AS355F1 lost control and a main rotor blade came off when the upper rod end left the fore/aft servo, whose threads were badly worn. The pilot died; inspections had missed the wear.Type: System failureNTSB docket |
Two fatal accidents in the United States since 2008 count toward the AS355's score, and neither began with an engine failure, the one problem a second engine is there to solve. That record is too short to say much about the type, and what it does show points at maintenance and a hard job at a power line.
Who still flies the TwinStar?
The AS355 is the twin-engine sister of the AS350 AStar, now sold as the Airbus H125. It first flew in 1979, has about six seats and is no longer built. The US fleet is small and shrinking: the FAA register held 67 in 2008 and 32 in 2026 in our count. We estimate about 0.4 million US flights since 2008, the fewest of the eight twin-engine helicopters we rate. One of the counted accidents was a flight with only the pilot on board, and the other was power-line work.
How much can two accidents tell you?
Not much on their own. We count fatal accidents in the US from 2008, taken from the NTSB database, and we estimate flights from the FAA aircraft register and the FAA General Aviation survey at about 0.77 hours per flight, a flight being take-off to final landing, measured on ADS-B tracks. Accidents in Puerto Rico and the US Virgin Islands are left out; the AS355 has none there since 2008. Accidents of helicopters on foreign registers are left out too, because we count flights only for US-registered ones. Each type's share of the twin-engine class's flights follows its registered aircraft and how much that type flies, mostly from airframe hours in NTSB accident records and partly from hours per aircraft seen by ADS-B receivers from 2019 to 2022: the remaining TwinStars flew a little fewer hours per aircraft than the average twin, on longer flights.
Per flight, the AS355's own record is about three and a half times that of the twin-engine class as a whole and close to the single-engine turbine average. With so few flights, the class average carries more than half the weight in its score, and the likely range of that score is wide. It shares its place with twins that have longer records, the AW109 and the Bell 429, a little behind the Sikorsky S-76 and the Airbus H130. Confidence is low, and one more accident would move it a lot. Helicopters score far lower than airliners, because a helicopter flight carries much more risk than an airline flight. The method and the helicopter ranking give the detail.
The accidents
Up to 28 October 2026, the two counted accidents killed three people. A third fatal crash, in Pennsylvania, is outside the count.
- 15 September 2012, West Windsor, New Jersey. In cruise, a main rotor blade came off after the upper rod end separated from the fore/aft servo, whose threads were badly worn. A 100-hour inspection that morning and a 600-hour one three months earlier had not found the wear. The pilot died.
- 17 October 2012, Tinicum Township, Pennsylvania (not counted). The pilot took off in the dark from a helipad behind his home, flew into patchy fog, became disoriented and hit trees. He died. The helicopter was on the Canadian register (C-FXGM), and we count only US-registered helicopters, the ones whose flights we can estimate.
- 30 October 2018, East Beekmantown, New York. During power-line work, the skid hit a pole while the helicopter hovered in a tailwind, and it rolled into live lines. The pilot and a lineman working from an outside bench died.
By occurrence type the two counted accidents are one system failure (the rotor controls) and one flight into an obstacle. Neither was an engine failure.
Before you fly in an older twin
- If you pay for the flight, ask for the operator's Part 135 certificate. Private flights run under Part 91, with less FAA oversight.
- Ask when the main rotor servos and control rods were last inspected, and by whom. On a helicopter built decades ago, that work matters more than the second engine.
- Look up the N-number in the FAA registry for the aircraft's age and owner, and in the NTSB database for its accident history.
- Decline a night departure into fog or low cloud, above all from a private pad with no lights or weather report.
- For work with people on external platforms, ask what approvals the operator holds and at what wind it stops the job.
Questions people ask
Is a twin-engine helicopter like the AS355 safer than a single-engine one?
Only for one kind of failure, a single engine stopping. None of the fatal US AS355 accidents since 2008 began with an engine failure: the two we count were a rotor-control failure and a collision with a pole, and a third, outside our count, was a loss of control in fog. Twin engines do not protect against those.
How many fatal AS355 accidents has the US had?
Our data counts two from 2008 up to 28 October 2026, with three deaths, in an estimated 0.4 million US flights. Per flight that is about three and a half times the average of the twin-engine helicopters we rate, but with only two events, one accident more or less changes the picture a lot.
Is the AS355 still in production?
No. Airbus built about 600 AS355 helicopters. The FAA register lists 32 in our count in 2026, down from 67 in 2008.
How do I know if my helicopter is an AS355?
Flight trackers and flight plans show the ICAO type code AS55. It looks much like the single-engine H125 but has two engines.
Sources
- 1.NTSB docket: Eurocopter AS355F2, Beekmantown, New York, 30 October 2018 (opens in a new tab) · National Transportation Safety Board
- 2.NTSB docket: Eurocopter AS355, Erwinna, Pennsylvania, 17 October 2012 (opens in a new tab) · National Transportation Safety Board
- 3.NTSB docket: Eurocopter AS355F1, West Windsor, New Jersey, 15 September 2012 (opens in a new tab) · National Transportation Safety Board
- 4.SafetyScorer exposure model: FAA aircraft register, FAA General Aviation and Part 135 Activity Survey, OpenSky ADS-B, NTSB airframe hours (opens in a new tab)Flights of all kinds in the United States (private, training, charter and other civil use) 2008 to 3 November 2026, each counted from take-off to final landing: the hours of all US twin-engine turbine helicopters in each year (active aircraft and hours from the FAA General Aviation and Part 135 Activity Survey), split between types by US-registered aircraft (FAA register, 33 of this type in 2024) times how much each type flies against its class (0.94, mostly from airframe hours in NTSB accident records, partly from hours per aircraft seen by ADS-B receivers in 2019-2022), at 0.77 hours per flight from ADS-B tracks: about 397 flights per registered aircraft per year in 2024. Flights and accidents outside the United States, or before 2008, are not used. Against the FAA's hours per helicopter model, this method is off by about 22% on a typical type. Uncertainty roughly ±20%.