Air Tractor INC AT-502A accident near Stratford, California, January 10, 2024
On January 10, 2024 at about 6:10 pm local time, a 1995 Air Tractor INC AT-502A, registered N6126U, was substantially damaged in an accident during initial climb near Stratford, California (Blair Air airport). It was a positioning 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
A partial loss of engine power due to the malfunction of the engine compressor bleed-off valve.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- January 10, 2024 · about 6:10 pm local time
- Place
- Stratford, California · Blair Air · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Air Tractor INC AT-502A, built 1995 · all AT-502As on the register
- Registration
- N6126U · registry record · serial 502A-0298
- Damage
- Substantial damage
- Flight
- Positioning flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot was repositioning an empty agricultural airplane for fertilizer application. During takeoff, the airplane failed to develop full power. At about 200 feet above ground level (agl) the engine rolled back to near idle. The pilot’s attempt to vary the power lever inputs did not affect engine power output, and he initiated a forced landing into a grove of small pistachio trees and soft dirt. Postaccident examination of the engine and follow-up bench testing of the engine compressor bleed-off valve (BOV) revealed an abnormal amount of air leaking around the piston. Disassembly of the BOV revealed a piston ring set was stuck within the piston groove, consistent with an abnormal air leak and irregular function. Abrasive and adhesive wear was observed on the piston rings and piston groove. The wear was likely due to environmental contaminants or twisting in the BOV’s metal piston ring profile. Based on the condition of the BOV’s rings, the BOV likely did not fully close during the accident flight, which resulted in a partial loss engine power during takeoff.
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
- Loss of engine power (total) during initial climb defining event
The NTSB's findings
- Aircraft › Aircraft power plant › Engine bleed air system › Compressor bleed valve › Malfunction
Pilot
- Certificate: commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane; rotorcraft: helicopter
- Flight time: 28,147 hours in all; 40 in the last 90 days; 9 in the last 30 days; 28,047 as pilot in command
- Last flight review: March 4, 2023
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: sngl
- Injury: no injuries
The aircraft
- Airframe total time: 11,195 hours
- Last inspection: 100-hour inspection, November 5, 2023; 26 hours since
- Maximum gross weight: 8,000 lb
- Seats: 1
- Landing gear: fixed
- Engine: Pratt & Whitney PT6A-65R (turboprop); 26,641 hours total
- Operator: Blair Ground Services
The flight
- Departed from: PVT Lemoore CA at 6:10 pm
- Destination: D86 Visalia CA
- Flight plan: none
- Runway 36, 3,900 ft by 60 ft
Weather at the time
- Light: daylight
- Wind: from 330° at 5 knots
- Visibility: 10 statute miles
- Sky: clear at 9,000 ft
- Temperature: 48°F (9°C), dew point 39°F (4°C)
- Altimeter: 30.19 inHg
- Observation at 9:56 am from KNLC, 11 miles away
Weather report (METAR): KNLC 101756Z 33005KT 10SM FEW090 FEW220 09/04 A3019 RMK AO2 SLP222 RH/71 T00940044 10094 20022 51010
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
13 documents, released by the NTSB on February 11, 2026. 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, 11 pages | View Download |
| 2 | Mor Pilot's Statement | PDF, 1 page | View Download |
| 3 | Mor FAA Interview | PDF, 1 page | View Download |
| 4 | Engine Exam Summary | PDF, 11 pages | View Download |
| 5 | Bov Pwc Email Summary | PDF, 1 page | View Download |
| 6 | Engine Monitoring File | data file | Download |
| 7 | Engine Logbook #2 Excerpt | PDF, 16 pages | View Download |
| 8 | Engine Logbook #3 | PDF, 26 pages | View Download |
| 9 | Propeller Logbook | PDF, 9 pages | View Download |
| 10 | Airframe Logbook #2 Part 2 | PDF, 10 pages | View Download |
| 11 | NTSB Certification of Party Representative Form | PDF, 2 pages | View Download |
| 12 | Release of Wreckage WPR24FA070 | PDF, 1 page | View Download |
| 13 | Photo Array | PDF, 6 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.