Mcdonnell Douglas 369E accident near Kemmerer, Wyoming, September 2, 2001
On September 2, 2001 at about 5:50 pm local time, a Mcdonnell Douglas 369E (helicopter), registered N440TJ, was substantially damaged in an accident near Kemmerer, Wyoming. It was an other work-use flight under external-load helicopter rules (Part 133). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
loss of tail rotor effectiveness while hovering. A contributing factor was the wind gust.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- September 2, 2001 · about 5:50 pm local time
- Place
- Kemmerer, Wyoming · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Mcdonnell Douglas 369E
- Registration
- N440TJ · no longer on the register · serial 0442E
- Damage
- Substantial damage
- Flight
- Other work-use flight · external-load helicopter rules (Part 133)
The NTSB's narrative final · quoted from the NTSB record
The pilot was transporting bags of seismic equipment by long line to a remote site. While he hovered into the wind waiting for a flagger, the helicopter was struck by a wind gust and started turning right. The pilot applied left pedal, but was unable to stop the rotation. The helicopter struck terrain, breaking off both skid legs, tail rotor blades, and tail rotor gearbox. FAA's Advisory Circular 90-95 defines the loss of tail rotor effectiveness as "a critical, low-speed aerodynamic flight characteristic that can result in an uncommanded rapid yaw rate which does not subside of its own accord and, if not corrected, can result in the loss of aircraft control." Some of the conditions conducive to LTE include (1) a high power setting, (2) low airspeed, and (3) a tailwind or left crosswind.
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: commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane; rotorcraft: helicopter
- Flight time: 1,584 hours in all; 66 in this make and model; 31 in the last 90 days; 8 in the last 30 days; 1,491 as pilot in command
- Last flight review: July 30, 2001
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 8,234 hours
- Last inspection: approved inspection programme, August 28, 2001; 67 hours since
- Maximum gross weight: 3,000 lb
- Seats: 5
- Landing gear: fixed
- Engine: Allison 250-C20B (turboshaft); 0 hours total
- Operator: Omni Aviation Services
The flight
- Departed from: NONE Kemmerer WY at 5:47 pm
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 160° at 6 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 73°F (23°C), dew point 43°F (6°C)
- Altimeter: 30.21 inHg
- Observation at 5:35 pm from BPI, 65 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 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.