Aerospatiale SA316B accident near Vernal, Utah, December 3, 1990
On December 3, 1990 at about 9:45 pm local time, a Aerospatiale SA316B (helicopter), registered N316BS, was destroyed in an accident near Vernal, Utah. It was a flight of an unrecorded kind under charter and air-taxi rules (Part 135). 3 people had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
A MALFUNCTION/FAILURE OF THE HELICOPTER'S MAIN ROTOR LEAD-LAG DAMPER.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- December 3, 1990 · about 9:45 pm local time
- Place
- Vernal, Utah · map
- Type
- Accident
- Injuries
- 3 people had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Aerospatiale SA316B
- Registration
- N316BS · registry record · serial 5399
- Damage
- Destroyed
- Flight
- Flight of an unrecorded kind · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
THE ACFT DEVELOPED VIBRATIONS IN FLT WITH SEVERE FEEDBACK THROUGH THE CONTROL SYSTEM TO THE CYCLIC STICK. THE PILOT INITIATED AN EMERGENCY LANDING AND LOST CONTROL JUST BEFORE TOUCHDOWN. THE ACFT IMPACTED THE GROUND WHILE SPINNING AND ROLLED OVER. EVIDENCE INDICATED A MALFUNCTION/FAILURE OF A MAIN ROTOR DAMPER.
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: single-engine land; rotorcraft: helicopter
- Flight time: 7,363 hours in all; 2,055 in this make and model; 147 in the last 90 days; 35 in the last 30 days; 7,363 as pilot in command
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: rgt
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- Maximum gross weight: 4,850 lb
- Seats: 7
- Landing gear: fixed
- Engine: Turbomeca ARTOUSTE III (turboshaft); 0 hours total
- Operator: Avman Aviation Helicopter Svc
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 40 statute miles
- Sky: clear
- Temperature: 34°F (1°C), dew point 28°F (-2°C)
- Altimeter: 30.00 inHg
- Observation at 9:50 pm from VEL, 19 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 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.
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.