WPR17LA177 · Air Tractor Inc AT 802A
Air Tractor Inc AT 802A · Accident: loss of control on ground during landing
From Battle Mountain Airport (BAM) to Wells Municipal Airport/Harriet Field (LWL)
Event
- NTSB case
- WPR17LA177
- 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
- Government
- 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 Inc AT 802A
- Aircraft type
- Air Tractor AT-802
- 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
- N70LA
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Battle Mountain Airport (BAM), Battle Mountain, NVTo Wells Municipal Airport/Harriet Field (LWL), Wells, NV
- Aircraft age
- About 17 years (built 2000)
- 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
- Public Aircraft
- 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
- Landing · landing roll
- 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 control on ground
- 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 oper/perf/capability
- Environmental issues › Conditions/weather/phenomena
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The commercial pilot reported that at the conclusion of the flight, he entered the left downwind leg of the airport traffic pattern, and observed about 10 knot winds from the north. He subsequently configured the airplane for a wheel landing to runway 26. The tailwheel had been in the "locked" position from the time he departed on the accident flight. Shortly after the main landing gear touched down, the airplane began to veer to the right. As the tailwheel came down, the airplane suddenly departed the right side of the runway in a hard right turn. The left main landing gear impacted an imperfection in the runway, the airplane then rotated spinning 180 degrees to the right before it came to rest.
The pilot, experienced in the accident airplane make and model, reported no mechanical anomalies with the control system before the accident. Postaccident examination of the control system revealed no abnormalities with the rudder and aileron. The pilot further stated that he departed with the tailwheel in the "locked" position, and only disengaged the locking mechanism during the landing roll to regain control of the airplane. The manufacturer reported that landing with the tailwheel in the "unlocked" position will typically result in a tailwheel shimmy, and may not have led to a further loss of directional control. A weather study indicated an absence of fronts and weather systems and a presence of variable winds consistent with local circulations and thermals at the time of the accident. Additionally, the airport manager reported that thermal activity is prevalent at her airport, and that multiple runway excursions occur each year due to variable wind conditions and other phenomena. With the presence of variable winds in the morning and subsequent thermal activity at the time of the accident, it is likely that a sudden wind shift or thermal activity overwhelmed the pilot, which resulted in a loss of directional control and the airplane's subsequent excursion from the runway.
Probable cause
The pilot's failure to maintain directional control during a period of thermal activity, which led to a runway excursion and impact with terrain.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR17LA177
- Event ID
- 20170731X70626
- Case number
- WPR17LA177
- 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: 19b9809e3285f8590d60138a2ef43eb5afcb49c4f6cef3ec03f5aa167d08e443; retrieved 2026-09-16T05:38:06.973Z.