Bell 206B3 accident near Three Forks, Montana, January 15, 2011
On January 15, 2011 at about 8:00 pm local time, a Bell 206B3 (helicopter), registered N78BR, was substantially damaged in an accident near Three Forks, Montana (Three Forks airport). It was a personal 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 inadequate use of throttle during the practice autorotation that resulted in a hard landing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- January 15, 2011 · about 8:00 pm local time
- Place
- Three Forks, Montana · Three Forks · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 206B3 · all 206B3s on the register
- Registration
- N78BR · registry record · serial 4001
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot practiced several maneuvers and then entered a straight-in practice autorotation. He pointed the helicopter into the wind at 800 feet above ground level near midfield and above the runway. He reduced the throttle to flight idle and lowered the collective while gently flaring the nose of the helicopter to set up the appropriate main rotor rpm and airspeed. He reported that he monitored those parameters carefully during the descent and noted that they remained well within the normal range. At the bottom of the descent, the pilot flared a little high to allow a margin of safety for tail boom clearance as he was planning a power recovery from the autorotation. The pilot stated that he did not add power at that point and that there was inadequate rotor inertia to dampen the landing, even though he applied full collective deflection. The helicopter hit hard and sustained substantial damage. The aft portion of the tail boom and tail rotor separated due to a main rotor blade contact and the skids were damaged.
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
What happened, in order
- Autorotation Hard landing defining event
The NTSB's findings
- cause Aircraft › Aircraft power plant › Engine controls › Power lever › Incorrect use/operation
- cause Personnel issues › Task performance › Use of equip/info › Use of equip/system › Pilot
Pilot
- Certificate: private
- Ratings: rotorcraft: helicopter
- Flight time: 692 hours in all; 674 in this make and model; 26 in the last 90 days; 4 in the last 30 days; 607 as pilot in command
- Last flight review: April 11, 2009
- Medical certificate: Class 3 (with waivers/limitations)
- Seat: rgt
- Injury: no injuries
The aircraft
- Airframe total time: 2,701 hours
- Last inspection: annual inspection, June 23, 2010
- Maximum gross weight: 3,200 lb
- Seats: 5
- Landing gear: fixed
- Engine: Rolls-Royce Allison 250-C20J (turboshaft); 0 hours total
- Operator: Skymission LLC
The flight
- Departed from: BZN Bozeman MT at 7:15 pm
- Destination: BZN Bozeman MT
- Flight plan: none
- Runway 02, 5,100 ft by 60 ft
Weather at the time
- Light: daylight
- Wind: from 310° at 4 knots
- Visibility: 10 statute miles
- Sky: a few clouds at 7,500 ft
- Temperature: 41°F (5°C), dew point 27°F (-3°C)
- Altimeter: 30.11 inHg
- Observation at 7:56 pm from KBZN
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 |
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.
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.