Cessna 172H accident near El Monte, California, January 6, 2020
On January 6, 2020 at about 9:09 pm local time, a 1966 Cessna 172H, registered N1658F, was substantially damaged in an accident during maneuvering near El Monte, California (San Gabriel Valley 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 inflight separation of a section of a propeller blade due to a fatigue crack which resulted in a forced landing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- January 6, 2020 · about 9:09 pm local time
- Place
- El Monte, California · San Gabriel Valley · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 172H, built 1966 · all 172Hs on the register
- Registration
- N1658F · registry record · serial 17255053
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that during the flight, the airplane suddenly vibrated severely followed by a sudden loss of engine power and the appearance of oil on the windscreen. The pilot noticed that the propeller was not rotating along with visible damage to the engine cowling. The pilot initiated a forced landing to a nearby airport and landed uneventfully. Postaccident examination of the airplane revealed that the engine mount was bent, and a portion of one propeller blade had separated in flight. Examination of the propeller revealed that it exhibited a fracture chordwise across the propeller approximately 12 inches outboard of the center of the propeller hub. The leading-edge area of the fracture exhibited an area of darker coloration and smoother surface texture along with fracture features consistent with progressive crack growth on the fracture surface in the area. The signatures were consistent with a fatigue fracture originating at the leading edge of the propeller
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
What happened, in order
- Part(s) separation from AC during maneuvering defining event
The NTSB's findings
- Aircraft › Aircraft propeller/rotor › Propeller system › Propeller blade section › Fatigue/wear/corrosion
- Aircraft › Aircraft propeller/rotor › Propeller system › Propeller blade section › Failure
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: instrument airplane; instrument: airplane
- Flight time: 5,208.7 hours in all; 1,258.4 in this make and model; 159.5 in the last 90 days; 44.2 in the last 30 days; 5,064.4 as pilot in command; 4,363.8 on instruments
- Last flight review: January 30, 2018
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 9,794 hours
- Last inspection: 100-hour inspection, December 4, 2019; 33 hours since
- Maximum gross weight: 2,299 lb
- Seats: 4
- Landing gear: fixed
- Engine: Continental O-360-A4M (piston); 0 hours total
The flight
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 77°F (25°C), dew point 25°F (-4°C)
- Altimeter: 30.23 inHg
- Observation at 9:47 pm from KEMT
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight 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.
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 WPR20LA062.