WPR12LA135 · Cook Smith AVN Replica SU
Cook Smith AVN Replica SU · Accident: loss of control on ground during landing
From St Johns Industrial Air Park (SJN) to St Johns Industrial Air Park (SJN)
Event
- NTSB case
- WPR12LA135
- 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
Cook Smith AVN Replica SU
- Aircraft type
- Cook SMITH AVN REPLICA SU
- 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
- N712AZ
- Operator
- Clayton McMartin
- Onboard fatalities
- Unknown
- Route
- From St Johns Industrial Air Park (SJN), St. Johns, AZTo St Johns Industrial Air Park (SJN), St. Johns, AZ
- Aircraft age
- Not recorded
- 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
- 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
- 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 had recently purchased the airplane and was receiving instruction in it. The pilot reported that the day before the accident, during landing, the left brake became less responsive than the right, and the airplane veered off of the runway but incurred no damage. The pilot and his flight instructor then bled the brake lines. This was followed by taxi and touch-and-go landing checks with no anomalies noted. The following morning the brakes were tested again and were operational. During the fourth landing that morning, the right brake locked up, and the airplane swerved to the right and nosed over. Although the flight instructor indicated that he had signed off the pilot for his tailwheel endorsement the day of the accident, he did not hold a current airman medical certificate. Additionally, the instructor reported that he did not remain on the flight controls with the pilot during the landings. Postaccident examination of the brake system revealed no evidence of a mechanical malfunction or failure that would have precluded normal operation.
Probable cause
The pilots’ failure to maintain directional control when the right brake locked up during the landing roll for reasons that could not be determined because postaccident examination did not reveal any anomalies that would have precluded normal operation.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR12LA135
- Event ID
- 20120314X71745
- Case number
- WPR12LA135
- 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: faa14cf1a0ea9b866b3100cab58ca5793d1a38a6b0e7d67f93c8de0618063892; retrieved 2026-09-15T17:27:48.236Z.