Mooney M20D accident near Herlong, California, March 18, 1991
On March 18, 1991, a Mooney M20D, registered N1921Y, was substantially damaged in an accident near Herlong, California. It was a personal flight under general aviation rules (Part 91). No one was hurt; 3 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
THE INADEQUATE PREPARATION OF THE PROPELLER DURING OVERHAUL. THE INSTALLATION OF AN IMPROPER PITCHED PROPELLER AND THE FATIGUE FAILURE OF THE PROPELLER BLADE EMANATING FROM CORROSION WERE FACTORS IN THE ACCIDENT.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- March 18, 1991
- Place
- Herlong, California · map
- Type
- Accident
- Injuries
- No one was hurt; 3 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Mooney M20D · all M20Ds on the register
- Registration
- N1921Y · no longer on the register · serial 216
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
THE AIRCRAFT HAD BEEN IN CRUISE FLIGHT AT AN ALTITUDE OF 7500 FEET MSL FOR TWO AND A HALF HOURS WHEN A BLADE SEPARATED FROM THE FIXED PITCH PROPELLER. THE PILOT SECURED THE ENGINE, STOPPED THE ROTATION OF THE PROPELLER AND LANDED ON A ROAD WITHOUT FURTHER INCIDENT. A POST ACCIDENT ANALYSIS OF THE PROPELLER FAILURE DISCLOSED A FATIGUE CRACK EMANATED FROM A CORROSION AREA ON THE CAMBER SIDE OF THE BLADE.
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; instrument: airplane
- Flight time: 1,940 hours in all; 1,000 in this make and model; 39 in the last 90 days; 20 in the last 30 days; 1,781 as pilot in command
- Medical certificate: Class 1 (valid medical--no waivers/lim.)
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded, January 2, 2000
- Maximum gross weight: 2,500 lb
- Seats: 4
- Landing gear: retractable
- Engine: Lycoming 0360 (piston); 0 hours total
The flight
- Departed from: 61S Cottage Grove OR at 10:00 pm
- Destination: PO6 Bullhead City AZ
- Flight plan: VFR
- Runway 0
Weather at the time
- Light: daylight
- Visibility: 50 statute miles
- Sky: clear
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 2 |
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.