Mooney M20F incident near Saratoga, Wyoming, September 5, 1984
On September 5, 1984 at about 4:00 pm local time, a Mooney M20F, registered N9121V, suffered minor damage in an incident near Saratoga, Wyoming. It was a business flight under general aviation rules (Part 91). No one was hurt; 2 people were 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 incident. 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
- September 5, 1984 · about 4:00 pm local time
- Place
- Saratoga, Wyoming · map
- Type
- Incident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Mooney M20F · all M20Fs on the register
- Registration
- N9121V · registry record · serial 690029
- Damage
- Minor damage
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
WHILE IN LEVEL CRUISE FLT AT 10500 FT, THE PLT HEARD A HIGH-PITCHED WHINE THAT LASTED FOR ABOUT 5 SECONDS. THE ENGINE THEN SEIZED AND THE PLT MADE A FORCED LANDING IN MOUNTAINOUS FOOTHILLS. DURING THE LANDING ROLL, THE LANDING GEARCOLLAPSED. EXAMINATION OF THE DISASSEMBLED ENGINE REVEALED EVIDENCE OF HIGH HEAT DISTRESS AND A FRACTURED CRANKSHAFT. DETAILED EXAMINATION OF THE CRANKSHAFT REVEALED EVIDENCE OF A LACK OF LUBRICATION AND FATIGUE. MAINTENANCE RECORDS REVEALED THAT THE ACFT WAS INVOLVED IN A GEAR COLLAPSE INCIDENT IN 1977 THAT RESULTED IN A PROP STRIKE AND SUDDEN ENGINESTOPPAGE. THE ENGINE WAS NOT DISASSEMBLED AND INSPECTED AT THAT TIME AS SUGGESTED BY AVCO LYCOMING SERVICE LETTER NO. L163B.
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: 7,842 hours in all; 5,842 in this make and model; 41 in the last 90 days; 41 in the last 30 days; 7,842 as pilot in command
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- Maximum gross weight: 2,740 lb
- Seats: 4
- Landing gear: retractable
- Engine: Lycoming IO-360-A1A (piston); 0 hours total
The flight
- Departed from: FML Fort Collins CO at 3:10 pm
- Destination: PIH Pocatello ID
- Flight plan: VFR
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 060° at 5 knots
- Visibility: 60 statute miles
- Sky: scat at 12,000 ft
- Temperature: 72°F (22°C), dew point 39°F (4°C)
- Altimeter: 30.00 inHg
- Observation at 3:55 pm from RWL, 37 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 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.
About this page
Everything above comes from the NTSB's public accident database: the narrative, probable cause and findings are the NTSB's own words, and the coded tables behind its report (pilot, aircraft, flight, weather, injuries, sequence of events) are written out in plain English. Pilots' ages, home towns and medical details are left out on purpose. The documents and photographs are the NTSB's docket, the folder of records gathered during the investigation, shown as the NTSB released them (the NTSB redacts some personal details first) and listed under the NTSB's own titles. This site's own text never names pilots, passengers or anyone else involved. A preliminary report describes what is known soon after the event and can change; the final report, with the probable cause, usually follows one to two years later and this page is refreshed when it does. Case number DEN84IA281.