Sikorsky S-55B accident near Richey, Montana, July 20, 1984
On July 20, 1984 at about 4:30 pm local time, a Sikorsky S-55B (helicopter), registered N24111, was substantially damaged in an accident near Richey, Montana. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). 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 November 2, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 20, 1984 · about 4:30 pm local time · cases in 1984
- Place
- Richey, Montana · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Sikorsky S-55B · all S-55Bs on the register
- Registration
- N24111 · registry record · serial 55237
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
THE PILOT STATED THAT HE LANDED IN A PASTURE WHERE HE INTENDED TO REFUEL. DURING THE LANDING ROLL, ONE OF THE WHEELS DROPPED INTO A HOLE, CAUSING THE MAIN ROTOR BLADE TO FLEX DOWNWARD AND SEVERE THE TAILBOOM.
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; instructor: airplane single-engine; instructor: helicopter; instrument: airplane; rotorcraft: helicopter
- Flight time: 3,422 hours in all; 65 in this make and model; 3,200 as pilot in command
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: unk
The aircraft
- Airframe total time: 3,857 hours
- Last inspection: approved inspection programme, April 11, 1984; 110 hours since
- Maximum gross weight: 7,200 lb
- Seats: 1
- Landing gear: fixed
- Engine: Curtis Wright R-1300 (piston); 0 hours total
The flight
- Departed from: Richey MT at 4:00 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 225° at 5 knots
- Visibility: 15 statute miles
- Sky: clear
- Temperature: 81°F (27°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.
Connections how this case links to the rest of the register
- N24111 on the register today · the tail number may have moved to another aircraft since
- Sikorsky S-55 15 registered today · the model family and its accident history
- Sikorsky 827 aircraft on the register
- Engine: Curtis Wright R-1300 · as the NTSB recorded it
- Accidents and incidents in Montana 1,121 since 1982 · 166 in the last ten years
- Montana 6,044 aircraft registered
The whole map of how records connect · these connections as data: /graph/accident/DEN84LA230.json.
The bigger picture in Aviation Analytics: accidents over time since 1982, by model, by phase of flight and conditions, by place and on the map.
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 does not name anyone involved, its policy at this time. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.