Cessna 210M accident near Fallbrook, California, November 20, 1990
On November 20, 1990 at about 8:00 pm local time, a Cessna 210M, registered N9139M, was destroyed in an accident near Fallbrook, California. It was a business flight under general aviation rules (Part 91). 1 person was seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
THE FAILURE OF THE NUMBER 5 CYLINDER PISTON CONNECTING ROD DUE TO BENDING AND SUBSEQUENT FATIGUE FRACTURE. CONTRIBUTING TO THE ACCIDENT WAS THE IMPROPER STARTING PROCEDURE ACCOMPLISHED BY AN UNIDENTIFIED PERSON WHICH RESULTED IN EXCESSIVE FUEL IN THE CYLINDER RESULTING IN A HYDRAULIC LOCK WITHIN THE NUMBER 5 CYLINDER.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- November 20, 1990 · about 8:00 pm local time
- Place
- Fallbrook, California · map
- Type
- Accident
- Injuries
- 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 210M · all 210Ms on the register
- Registration
- N9139M · no longer on the register · serial 62064
- Damage
- Destroyed
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
A CESSNA 210M LOST ENG POWER AND COLLIDED WITH A POLE AFTER A FORCED LANDING ON A CITY STREET. THE ENGINE CRANKCASE WAS FRACTURED AND THE #5 PISTON CONNECTING ROD HAD SEPARATED FROM THE ENG AND WAS FOUND ALONG THE WRECKAGE PATH. EXAM OF THE NUMBER 5 CYLINDER WALL DISCLOSED EVIDENCE OF THE AREA BELOW THE NORMAL PISTON STROKE BEING SCRAPED BY THE PISTON RINGS. ACCORDING TO THE METALLURGIC REPORT, THE PISTON'S CONNECTING ROD FAILED DUE TO A FATIGUE CRACK. THE CONNECTING ROD WAS BENT SOME TIME AFTER INITIAL ENG OPERATION. THE BENDING THAT OCCURRED TO THE NO. 5 CONNECTING ROD IS CHARACTERISTIC OF AN HYD LOCK CONDITION WHERE THE PISTON IS FORCED AGAINST INCOMPRESSIBLE FLUIDS BETWEEN THE PISTON AND CYLINDER HEAD. NO INDICATION OF METALLURGICAL DEFECT WAS OBSERVED IN THE CONNECTING ROD. HARDNESS READINGS ON THE CONNECTING ROD, WHICH INDICATES THE STRENGTH, CONFORMED TO MATERIAL SPECIFICATIONS. THE MAINTENANCE RECORDS NOTE THAT A MAJOR OVERHAUL WAS ACCOMPLISHED 207.8 HOURS BEFORE THE ACCIDENT.
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; instrument: airplane
- Flight time: 500 hours in all
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 1,942 hours
- Last inspection: annual inspection, August 9, 1989; 208 hours since
- Maximum gross weight: 3,400 lb
- Landing gear: retractable
- Engine: Continental IO-520L (piston); 0 hours total
- Operator: Self Enterprises
The flight
- Destination: Unknown
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Sky: clear
- Temperature: 0°F (-18°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.
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.