ERA21LA367 · Collins Robert S JUST ACFT HIGHLANDER
Collins Robert S JUST ACFT HIGHLANDER · Accident: system/component malfunction/failure (non-power) during landing
Event
- NTSB case
- ERA21LA367
- 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
Collins Robert S JUST ACFT HIGHLANDER
- Aircraft type
- Collins Robert JUST ACFT HIGHLANDER
- 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
- N409JD
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From not recordedTo not recorded
- Aircraft age
- About 14 years (built 2007)
- 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 · 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
- System/component malfunction/failure (non-power)
- 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
The pilot of the tailwheel, experimental, amateur-built airplane reported that he had completed 11 takeoffs and landings to a full stop. During a subsequent takeoff, he saw that the left main landing gear wheel was wobbling. He returned to the turf airstrip and landed at the slowest possible speed; however, the left main landing gear wheel separated, and the airplane came to rest inverted on the runway. Examination of the wreckage by a Federal Aviation Administration inspector revealed substantial damage to the right wing and vertical stabilizer. Three lock nuts that secured the wheel were missing and not recovered. Additionally, there was no damage or stripping on the threads of the respective studs. The pilot could not see the three nuts during preflight inspection as they were concealed by a hubcap. The mechanic that completed a condition inspection about 2 months prior to the accident, stated that the three missing nuts were light locknuts, made of an alloy. The mechanic removed the hubcap during the inspection as he had to lubricate the wheel bearing. At that time, he could see that the three nuts were secure; however, since they were already set to a torque, he did not attempt to tighten them.
Probable cause
Failure of the left main landing gear wheel lock nuts, which resulted in a wheel separation and nose over during landing.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ERA21LA367
- Event ID
- 20210917103894
- Case number
- ERA21LA367
- 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, cause areas. 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: e8d13f2367279232b603925dc1a0147c8501f78aad9a128b949d2c50d274ccd4; retrieved 2026-09-16T14:32:57.941Z.