Air Tractor INC AT 301 accident near Pearsall, Texas, June 12, 2014
On June 12, 2014 at about 5:00 pm local time, a 1978 Air Tractor INC AT 301, registered N8593S, was substantially damaged in an accident during maneuvering near Pearsall, Texas. 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
The failure of the No. 1 cylinder rod at the link pin. Contributing to the accident was oil starvation to the rod bearing due to the improper flushing of the oil cooler, which allowed metal and other debris in the oil to clog the drain and the led to the piston’s failure.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 12, 2014 · about 5:00 pm local time
- Place
- Pearsall, Texas · 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 301 NO SERIES, built 1978 · all AT 301s on the register
- Registration
- N8593S · no longer on the register · serial 301-0157
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported that, while returning to the airport after spraying a cornfield, he noticed that the engine cylinder head temperature was high. After landing, he checked the engine cylinders for discrepancies and found none, so he decided to continue the spraying operations at the cornfield. As the pilot pulled up the airplane from a spray run, the engine started to vibrate and lose power. He subsequently made a forced landing in a nearby field, which resulted in the airplane sustaining substantial damage to both wings. During postaccident examination, a considerable amount of metal was found in the oil drain. The No. 2 cylinder front spark plug was loose. After removing all of the spark plugs, an attempt was made to rotate the engine, but it seized. After removing the No. 1 cylinder, it was discovered that the piston rod had broken at the link pin; no other rods were broken. The No. 1 cylinder link pin was scored, and there was evidence of oil starvation at the rod bearing. According to the operator, the engine had accrued about 100 hours since it had received extensive maintenance, including the replacement of the crankshaft. It is likely that the oil cooler was not properly flushed when the crankshaft was replaced and that metal and other debris remained in the oil, clogged the drain, and caused the piston to fail.
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 (partial) during maneuvering defining event
- Off-field or emergency landing during emergency descent
- Collision with terrain or object (not controlled flight into terrain) during landing
The NTSB's findings
- cause Aircraft › Aircraft power plant › Engine (reciprocating) › Recip eng cyl section › Failure
- Environmental issues › Physical environment › Terrain › (general) › Contributed to outcome
- factor Aircraft › Aircraft power plant › Engine (reciprocating) › Recip eng cyl section › Incorrect service/maintenance
- factor Aircraft › Fluids/misc hardware › Fluids › Oil › Fluid level
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land
- Flight time: 472 hours in all; 220 in this make and model; 150 in the last 90 days; 11 in the last 30 days; 415 as pilot in command
- Last flight review: October 4, 2013
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: sngl
- Injury: no injuries
The aircraft
- Airframe total time: 8,357 hours
- Last inspection: annual inspection, May 27, 2014; 11 hours since
- Maximum gross weight: 5,000 lb
- Seats: 1
- Landing gear: fixed
- Engine: P&W R 1340-AN-1 (piston); 9,468 hours total
- Operator: Smith Company Flying Service
The flight
- Departed from: T30 Pearsall TX at 4:40 pm
- Destination: T30 Pearsall TX
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 150° at 12 knots, gusting 18
- Visibility: 9 statute miles
- Sky: clear
- Temperature: 93°F (34°C), dew point 72°F (22°C)
- Altimeter: 29.82 inHg
- Observation at 4:53 pm from KCOT, 23 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
7 documents, released by the NTSB on May 26, 2015. 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.
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.