WPR20LA306 · Piper PA-28-181
UAA International Piper PA-28-181 · Accident: landing gear collapse while taxiing
Event
- NTSB case
- WPR20LA306
- 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
- Event fatalities
- Unknown
- 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
Piper PA-28-181
- Aircraft type
- Piper PA-28
- 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
- N79MS
- Operator
- UAA International
- Onboard fatalities
- Unknown
- Route
- From not recordedTo not recorded
- Aircraft age
- About 42 years (built 1978)
- 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 91: General Aviation
- 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
- Taxi · to runway
- 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
- Landing gear collapse
- 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 from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
After landing, as the pilot was taxiing back to the runway for another takeoff, the right landing gear collapsed, and the right wing struck the runway resulting in substantial damage. Examination of the landing gear bolts revealed they failed due to reverse bending fatigue cracking. The size of the fatigue cracking area on the fracture surfaces versus the overstress area indicated the fatigue likely grew over time under low-to-moderate stress. The occurrence of the fatigue cracking on all the hex-head bolts and the similarities of the fatigue cracking areas on the fracture surfaces were consistent with some amount of movement on that side of the landing gear, which indicates there was likely an issue with preloading of the bolts.
Probable cause
The failure of the right landing gear due to fatigue cracking.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR20LA306
- Event ID
- 20200915X45814
- Case number
- WPR20LA306
- 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: local date, investigation status, coordinates, cause areas. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2020-08-19.
- API snapshot SHA-256: 3981d34fdb74ebbd58343824a874ac4f1bbc4b04d3349c4d7139c365149e8016; retrieved 2026-09-16T13:02:46.272Z.