Cessna 210D accident near Sheridan, Wyoming, November 21, 1999
On November 21, 1999 at about 4:00 am local time, a Cessna 210D, registered N3928Y, was substantially damaged in an accident near Sheridan, Wyoming (Sheridan County Airport). It was a personal flight under general aviation rules (Part 91). 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 partial failure of the engine driven hydraulic pump.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 21, 1999 · about 4:00 am local time
- Place
- Sheridan, Wyoming · Sheridan County Airport · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 210D · all 210Ds on the register
- Registration
- N3928Y · no longer on the register · serial 21058428
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot said that this was the first flight after the annual inspection. When he put the leading gear handle down for landing, he didn't get a positive gear lock light, so he cycled the leading gear several times in an attempt to get a positive gear down and locked indication. He attempted to hand pump the gear down, but still had no positive down and locked light. He landed the airplane, and during the landing roll the right main landing gear failed. Postaccident examination of the engine driven hydraulic pump pressure revealed that its output was 200 pounds per square inch (psi). The maintenance personnel that worked on the airplane said that normal pump pressure output was 2,725 psi. The hydraulic pump was replaced, and the landing gear cycled normally.
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: private
- Ratings: single-engine land
- Flight time: 172 hours in all; 22 in this make and model; 24 in the last 90 days; 15 in the last 30 days; 110 as pilot in command
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 3,725 hours
- Last inspection: annual inspection, November 20, 1999; 1 hours since
- Maximum gross weight: 3,100 lb
- Seats: 6
- Landing gear: retractable
- Engine: Continental I0-520 (piston); 0 hours total
The flight
- Departed from: BIL Billings MT at 3:25 am
- Destination: SHR
- Flight plan: none
- Runway 14, 8,300 ft by 100 ft
Weather at the time
- Light: night, bright
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 34°F (1°C), dew point 30°F (-1°C)
- Altimeter: 29.00 inHg
- Observation at 4:51 am from SHR
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.