Cessna 150D accident near Chino, California, August 25, 2021
On August 25, 2021 at about 4:45 pm local time, a 1964 Cessna 150D, registered N4375U, was substantially damaged in an accident during enroute near Chino, California (Chino airport). It was a personal flight under general aviation rules (Part 91). 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot’s delayed use of carburetor heat, which resulted in a loss of engine power due to carburetor icing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 25, 2021 · about 4:45 pm local time
- Place
- Chino, California · Chino · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Cessna 150D, built 1964 · all 150Ds on the register
- Registration
- N4375U · no longer on the register · serial 15060375
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot flew in the local area for about 2 hours 45 minutes and then began to return to the departure airport. While the airplane was descending to 2,500 ft mean sea level, the engine surged, prompting the pilot to use carburetor heat. After a brief period of normal engine operation, the engine surging resumed, resulting in a partial power loss as the airplane approached the airport. Despite the pilot’s attempts to troubleshoot the issue, the airplane was unable to maintain altitude. The pilot performed an off-airport landing, during which the airplane collided with a fence. During the recovery of the airplane, about 3.5 to 4 gallons of fuel from the left wing and about 0.5 gallons of fuel from the right wing were drained, and both the carburetor bowl and gascolator contained fuel. The fuel tanks in the wing were intact, but fuel was dripping from the left fuel vent due to the angle at which the airplane came to rest (left wing down). Because fuel was dripping from the vent, the investigation could not determine if the airplane had a sufficient amount of fuel aboard at the time of the engine failure; the amount of fuel found in the tanks did not represent the amount of fuel aboard before impact. The Federal Aviation Administration (FAA) Carburetor Icing Probability Chart revealed that the outside air temperature and dew point temperature were within the "serious icing at glide power" portion of the chart, and the pilot reported haze in the area. An FAA Special Airworthiness Information Bulletin emphasized the risk of carburetor icing, even in above-freezing conditions with visible moisture, due to fuel vaporization and air expansion. Thus, it is likely that carburetor icing during the accident flight resulted in the loss of engine power, which might have been mitigated if the pilot had applied carburetor heat earlier in the descent.
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
- Fuel related during enroute defining event
The NTSB's findings
- Environmental issues › Conditions/weather/phenomena › Temp/humidity/pressure › Conducive to carburetor icing › Contributed to outcome
- Personnel issues › Action/decision › Action › Delayed action › Pilot
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane single-engine; instrument: airplane
- Flight time: 735 hours in all; 111 in this make and model; 122 in the last 90 days; 36 in the last 30 days; 535 as pilot in command; 239 on instruments
- Last flight review: June 10, 2021
- Medical certificate: Class 1 (without waivers/limitations)
- Seat: left
- Injury: minor injuries
The aircraft
- Airframe total time: 4,878 hours
- Last inspection: annual inspection, October 2, 2020; 67.9 hours since
- Maximum gross weight: 1,600 lb
- Seats: 2
- Landing gear: fixed
- Engine: Continental O-200 (piston); 0 hours total
The flight
- Departed from: KCNO Chino CA at 1:25 pm
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 5 statute miles
- Sky: a few clouds at 20,000 ft
- Temperature: 79°F (26°C), dew point 61°F (16°C)
- Altimeter: 29.98 inHg
- Observation at 9:53 am from KCNO, 3 miles away
Weather report (METAR): SPECI 00000KT 5SM HZ FEW200 26/16 A2998
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
3 documents, released by the NTSB on September 20, 2023. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 7 pages | View Download |
| 2 | Record of Conversations | PDF, 2 pages | View Download |
| 3 | Pictures and Graphs | PDF, 2 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
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.