Eurocopter AS-350B-3 accident near Ketchikan, Alaska, September 23, 2000
On September 23, 2000 at about 9:45 pm local time, a Eurocopter AS-350B-3 (helicopter), registered N405AE, was substantially damaged in an accident near Ketchikan, Alaska. It was an instructional flight under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot's inadvertent activation of the collective flight stop/emergency fuel augmentation switch, which resulted in engine and main rotor overspeeds, thereby precipitating failures of the tail rotor drive shaft coupling and power turbine blades. A factor associated with the accident was the manufacturer's inadequate design of the flight stop switch, which has insufficient safeguards to preclude inadvertent activation.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 23, 2000 · about 9:45 pm local time
- Place
- Ketchikan, Alaska · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Eurocopter AS-350B-3 · all AS-350B-3s on the register
- Registration
- N405AE · registry record · serial 3286
- Damage
- Substantial damage
- Flight
- Instructional flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
Two commercial helicopter pilots, both certificated helicopter instructors, were in a turbine-powered helicopter practicing autorotations with a power recovery prior to touchdown. The flying pilot inadvertently activated the flight stop augmented fuel flow switch during a power recovery, and oversped the engine and main rotor. The other pilot joined him on the controls, and increased collective to reduce rotor rpm. The helicopter climbed abruptly to about 60 feet above the ground, where the tail rotor drive shaft separated. The engine subsequently lost power, and an autorotation was accomplished. Investigation disclosed that the engine and main rotor system had been exposed to significant overspeed conditions, resulting in a catastrophic failure of the turbine engine, and the tail rotor drive shaft coupling. The flight stop switch on the collective has no protective guard, and can be readily engaged, allowing the engine to enter the augmented fuel flow regime and, under certain conditions, causing the engine to overspeed. The switch has a history of inadvertent activation, and resultant engine overspeed events.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: instructor: helicopter; rotorcraft: helicopter
- Flight time: 3,850 hours in all; 2,550 in this make and model
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 92 hours
- Last inspection: approved inspection programme, September 20, 2000; 17 hours since
- Maximum gross weight: 4,961 lb
- Seats: 6
- Landing gear: fixed
- Engine: Turbomeca ARRIEL 2B (turboshaft); 0 hours total
The flight
- Departed from: 6Z4 AK at 4:35 pm
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 280° at 10 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 140°F (60°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 2 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
Other NTSB records under N405AE the same tail number, which may have belonged to a different aircraft at the time
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.