Aerospatiale SA316B accident near Alcova, Wyoming, June 3, 1984
On June 3, 1984 at about 11:00 pm local time, a Aerospatiale SA316B (helicopter), registered N4997A, was substantially damaged in an accident near Alcova, Wyoming. It was a flight of an unrecorded kind under charter and air-taxi rules (Part 135). 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
The NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 3, 1984 · about 11:00 pm local time
- Place
- Alcova, Wyoming · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Aerospatiale SA316B
- Registration
- N4997A · no longer on the register · serial 1312
- Damage
- Substantial damage
- Flight
- Flight of an unrecorded kind · charter and air-taxi rules (Part 135)
The NTSB's narrative final · quoted from the NTSB record
PLT STATED THAT THE APPROACH AND LANDING WERE NORMAL UNTIL GROUND RESONANCE STARTED AND THE BRAKES DID NOT HOLD. THE PLT ATTEMPTED TO PICK BACK UP TO A HOVER TO REPOSITION, BUT LOST DIRECTIONAL CONTROL. THE ACFT YAWED AND ROLLED TO THE LEFT ON NOSE. THE PLT STATED THAT HE 'WOULD PREFER TO BE ABLE TO FLY THE ALOUETTE III MORE OFTEN FOR PROFICIENCY.' THE ALOUETTE III MAIN ROTOR BLADES ROTATE IN THE OPPOSITE DIRECTION OF AMERICAN MANUFACTURED HELICOPTERS. THE PLT HAS LOGGED 8784 HRS IN AMERICAN MADE HELICOPTERS AND 20 HRS IN THE AEROSPATIALE HELICOPTERS.
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: 8,800 hours in all; 20 in this make and model; 30 in the last 90 days; 8,430 as pilot in command
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 4 hours
- Last inspection: 100-hour inspection, April 7, 1984; 3,605 hours since
- Maximum gross weight: 4,960 lb
- Seats: 7
- Landing gear: fixed
- Engine: Turbomeca ARTOUSTE III (turboshaft); 0 hours total
- Operator: Evergreen Helicopters INC
The flight
- Departed from: Casper WY at 10:35 pm
- Flight plan: none
- Runway 0
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 220° at 5 knots
- Visibility: 10 statute miles
- Sky: overcast; not recorded
- Temperature: 50°F (10°C), dew point 0°F (-18°C)
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.