Schweizer G-164B accident near Buttonwillow, California, February 12, 2009
On February 12, 2009 at about 4:15 pm local time, a Schweizer G-164B, registered N3626T, was substantially damaged in an accident during enroute (cruise) near Buttonwillow, California. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). 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
A loss of engine power due to the number four cylinder base nuts becoming loose, allowing the cylinder to detach from the engine case. Contributing to the accident was the pilot's impaired visibility due to smoke during the forced landing.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- February 12, 2009 · about 4:15 pm local time
- Place
- Buttonwillow, California · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Schweizer G-164B
- Registration
- N3626T · no longer on the register · serial 722B
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
While en route to an agriculture application job, the airplane's engine exhaust started shaking, then smoke started coming off the engine. The pilot landed on a farm road. During the landing his visibility was limited by the smoke, and the right wheel went off the road into soft mud. The airplane swerved to the right and nosed over. Examination of the engine disclosed that the number four cylinder base nuts had backed off, allowing the cylinder to separate from the engine case.
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
- Powerplant sys/comp malf/fail during enroute (cruise)
- Loss of engine power (partial) during enroute (cruise) defining event
- Nose over/nose down during landing (landing roll)
The NTSB's findings
- cause Aircraft › Aircraft power plant › Engine (reciprocating) › Recip eng cyl section › Failure
- factor Environmental issues › Task environment › Physical workspace › Visibility › Effect on personnel
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land
- Flight time: 8,500 hours in all; 5,000 in this make and model; 8,500 as pilot in command
- Last flight review: February 7, 2009
- Medical certificate: Class 2
- Seat: sngl
- Injury: no injuries
The aircraft
- Airframe total time: 9,290 hours
- Last inspection: annual inspection, September 14, 2008
- Maximum gross weight: 5,704 lb
- Seats: 1
- Landing gear: fixed
- Engine: Pratt & Whitney R1340 (piston); 0 hours total
- Operator: Vince Crop Dusters, Inc.
The flight
- Departed from: Buttonwillow CA
- Destination: Buttonwillow CA
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 7 statute miles
- Sky: clear
- Temperature: 43°F (6°C), dew point 37°F (3°C)
- Altimeter: 30.15 inHg
- Observation at 4:54 pm from KBFL, 22 miles away
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.
Other NTSB records under N3626T the same tail number, which may have belonged to a different aircraft at the time
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.