Hughes 369D accident near Baggs, Wyoming, February 16, 1999
On February 16, 1999, a Hughes 369D (helicopter), registered CGDCM, was substantially damaged in an accident near Baggs, Wyoming. It was an other work-use flight under general aviation rules (Part 91). 1 person was seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
A hard landing resulting from rotor rpm decay. Factors were the improper replacement of the turbine by company maintenance personnel resulting in the PC line nut becoming loose, and the pilot operating outside the normal height/velocity curve.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 16, 1999
- Place
- Baggs, Wyoming · map
- Type
- Accident
- Injuries
- 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Hughes 369D · all 369Ds on the register
- Registration
- CGDCM · no longer on the register · serial 310916D
- Damage
- Substantial damage
- Flight
- Other work-use flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The helicopter was conducting a seismic survey operation at 200 to 250 feet agl at 40 knots when the engine's automatic re-ignition system caution light illuminated, followed by an immediate loss of main rotor rpm. The pilot unsuccessfully attempted to perform an autorotation, and the aircraft impacted the ground. A postaccident examination of the turboshaft engine was performed, revealing that the PC line 'B' nut between the fuel control unit (FCU) and the power turbine governor (PTG) was not connected at the FCU, resulting in a loss of engine pneumatic pressure. According to aircraft maintenance records, the turbine section of the engine was removed by company maintenance and replaced with a rental turbine. The PC line and various pneumatic and fuel system lines had been removed to facilitate removal and replacement of the engine's turbine section. The helicopter had flown 6.1 hours since the turbine was replaced.
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: rotorcraft: helicopter
- Flight time: 2,298 hours in all; 51 in this make and model; 128 in the last 90 days; 41 in the last 30 days; 2,100 as pilot in command
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 10,762 hours
- Last inspection: approved inspection programme, January 16, 1999; 71 hours since
- Maximum gross weight: 3,550 lb
- Seats: 4
- Landing gear: fixed
- Engine: Allison 250-C20B (turboshaft); 0 hours total
The flight
- Departed from: NONE WY
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 250° at 15 knots
- Visibility: 40 statute miles
- Sky: broken clouds at 2,500 ft; not recorded
- Temperature: 32°F (0°C), dew point 19°F (-7°C)
- Altimeter: 30.00 inHg
- Observation at 10:59 pm from RWL, 45 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.