WPR09CA064 · Air Tractor AT-502
Gilbert Aviation Industries Air Tractor AT-502 · Accident: loss of engine power (total) while maneuvering
From Sequoia Field (D86) to Sequoia Field (D86)
Event
- NTSB case
- WPR09CA064
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Air Tractor AT-502
- Aircraft type
- Air Tractor AT-502
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N1035F
- Operator
- Gilbert Aviation Industries
- Onboard fatalities
- Unknown
- Route
- From Sequoia Field (D86), Visalia, CATo Sequoia Field (D86), Visalia, CA
- Aircraft age
- Not recorded
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 137: Agricultural
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Maneuvering · low-altitude flying
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Loss of engine power (total)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Aircraft › Aircraft power plant
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot reported that about halfway through the first spray pass he experienced a complete loss of engine power. The pilot stated that he pulled up out of the field, dumped the load, and chose to land straight ahead in an adjoining field. The pilot reported that after touching down and holding the stick back the tail started lifting. Before it stopped, the airplane nosed over and came to rest inverted. A Federal Aviation Administration (FAA) airworthiness aviation safety inspector conducted a post accident examination of the airplane. The airplane's most recent annual inspection had been completed the day prior to the accident. The FAA inspector found the engine's Py line had not been secured properly, which would have prevented proper fuel scheduling to the engine's fuel control unit. The inspector also reported that the outboard leading edge of the left wing tip had sustained substantial damage, which would have adversely affected the flight characteristics of the airplane.
Probable cause
The failure of maintenance personnel to properly install the engine's Py line correctly, which resulted in the total loss of engine power and subsequent force landing. Contributing to the accident was the lack of suitable terrain.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR09CA064
- Event ID
- 20081223X91642
- Case number
- WPR09CA064
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 7147eb5c9d4f4bbe3862724c1b091665bad23c44ff106dfc23d788e640b16be1; retrieved 2026-09-15T10:37:55.972Z.