ERA22LA171 · Cessna 172 F
Cessna 172 F · Accident: aircraft structural failure during landing
Event
- NTSB case
- ERA22LA171
- 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
Cessna 172 F
- Aircraft type
- Cessna 172
- 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
- N8431U
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From not recordedTo not recorded
- Aircraft age
- About 58 years (built 1964)
- 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
- 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
No findings designated as a cause are recorded in the NTSB data yet.
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
During a touch-and-go landing, the student pilot and flight instructor heard a pop sound as they touched down. The student pilot initiated a go-around and then informed the instructor that the left main landing gear (LMLG) had separated from the airplane. They flew for about 2.5 hours to reduce the airplane’s fuel load before attempting to land with the fractured LMLG. The landing was uneventful and the airplane came to a stop on the runway. According to the instructor the LMLG struck the horizontal stabilizer when it separated, resulting in substantial damage.
Examination of the left main landing gear spring strut revealed that the step bracket was tack welded onto the spring strut. According to the airplane manufacturer, step brackets can only be affixed to the spring strut using an approved epoxy adhesive; welding on the spring strut is not permitted. This improper maintenance resulted in a fatigue crack and the failure of the gear during the accident flight due to overstress.
Probable cause
Maintenance personnel’s failure to properly affix left main landing gear components, which led to the failure of the left main landing gear during the accident flight.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ERA22LA171
- Event ID
- 20220328104833
- Case number
- ERA22LA171
- 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, coordinates. 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: adad6edc012334752cb1bf98a24ca5a4446ee139b2296d2ee321cc5b8dba5d08; retrieved 2026-09-16T15:04:02.387Z.