WPR14LA130 · Grumman G164 - A
Trinkle Ag Flying Grumman G164 - A · Accident: aircraft structural failure during landing
From Caruthers, CA (no airport) to Caruthers, CA (no airport)
Event
- NTSB case
- WPR14LA130
- 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
Grumman G164 - A
- Aircraft type
- Grumman G164
- 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
- N72ES
- Operator
- Trinkle Ag Flying
- Onboard fatalities
- Unknown
- Route
- From Caruthers, CA (no airport)To Caruthers, CA (no airport)
- Aircraft age
- About 42 years (built 1972)
- 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
- Landing · flare/touchdown
- 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
- Aircraft structural failure
- 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 systems
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot completed his third aerial application sortie of the day in the airplane, and was returning for landing on the paved private airstrip. On touchdown, the pilot heard a "huge bang," and the airplane began to roll right wing down. The pilot tried to correct with aileron, but as the airplane slowed, its right wing contacted the ground. The airplane veered to the right, departed the paved surface, and struck an embankment that bordered the runway, which caused the airplane to nose over. The airplane came to rest inverted, partially down the embankment.
Examination of the airplane revealed that the right main landing gear leg had fractured and separated near the upper bend just below the fuselage. Laboratory analysis revealed that the leg failure was the result of a fatigue crack that went undetected until the remaining material was insufficiently strong to sustain the landing load. The fatigue crack originated at the site of electrical arc damage to the gear leg. Possible mechanisms for the arc damage included a power line strike, a lightning strike, improper grounding during weld repairs to the airframe, or processing damage during overhaul of the landing gear. Because the gear leg was heat-treated, the airplane manufacturer prohibited welding of the leg. The presence and condition of paint on the gear leg's surface at the site of the arc damage indicated that the damage occurred before the paint was applied and that the gear leg had not been painted in the recent past. Finding paint covering the damage raises questions about what inspections were performed on the gear leg and the efficacy of the inspections; however, because the maintenance records were not available, the history of the gear leg could not be determined.
Probable cause
An undetected fatigue crack in the landing gear leg, which initiated at an electrical arc-induced damage site of undetermined origin and resulted in landing gear failure. Contributing to the severity of damage to the airplane was the close proximity of an embankment to the runway.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR14LA130
- Event ID
- 20140304X75019
- Case number
- WPR14LA130
- 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: 3c19f37f5b2bce10c9f8b45527cac0a53bace3a3e9a4098f43e7c7c5cce86c91; retrieved 2026-09-15T23:21:59.208Z.