Consolidated-Vultee PBY-5A accident near Lewistown, Montana, May 9, 1985
On May 9, 1985 at about 2:44 pm local time, a Consolidated-Vultee PBY-5A, registered N84857, was substantially damaged in an accident near Lewistown, Montana (Lewistown airport). It was an aerial observation flight under general aviation rules (Part 91). 1 person was killed and 2 people had minor injuries. 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
- May 9, 1985 · about 2:44 pm local time
- Place
- Lewistown, Montana · Lewistown · map
- Type
- Accident
- Injuries
- 1 person was killed and 2 people had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Consolidated-Vultee PBY-5A
- Registration
- N84857 · registry record · serial 1522
- Damage
- Substantial damage
- Flight
- Aerial observation flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
DURING TAXI TO TAKEOFF THE BRAKES FAILED. THE PLT ATTEMPTED TO GROUNDLOOP THE ACFT. THE ACFT ROLLED DOWN HILL AND COLLIDED WITH A GULLY. THE PLT WAS FATALLY INJURED. DURING PREFLIGHT THE CO-PLT INADVERTENTLY ADDED HYDRAULIC FLUID IN THE ALCOHOL TANK. THE HYDRAULIC PUMP CAVITATED. THE PLT FAILED TO USE THE HYDRAULIC EMERGENCY HAND PUMP OR THE A.C. ELECTRIC PUMP.
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 multi-engine; instructor: airplane single-engine; instrument: airplane
- Flight time: 6,838 hours in all; 19 in this make and model; 24 in the last 90 days; 18 in the last 30 days
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 1,481 hours
- Last inspection: annual inspection, January 1, 1985; 35 hours since
- Maximum gross weight: 27,000 lb
- Seats: 3
- Landing gear: retractable
- Engine: P&W R1830-94-M2 (piston); 0 hours total
The flight
- Destination: RNO Reno NV
- Flight plan: none
- Runway 25, 7,984 ft by 100 ft
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 120° at 3 knots
- Visibility: 30 statute miles
- Sky: broken clouds at 8,000 ft; not recorded at 8,000 ft
- Temperature: 55°F (13°C), dew point 45°F (7°C)
- Altimeter: 29.00 inHg
- Observation at 2:52 pm from LWT
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | 1 | ||
| Passengers | 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.