WPR17LA114 · Tappen Chris VELOCITY SUV
Tappen Chris VELOCITY SUV · Accident: system/component malfunction/failure (non-power) during landing
From Pierce County-Thun Field (PLU) to Pierce County-Thun Field (PLU)
Event
- NTSB case
- WPR17LA114
- 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
Tappen Chris VELOCITY SUV
- Aircraft type
- Tappen Chris VELOCITY SUV
- 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
- N399DG
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Pierce County-Thun Field (PLU), Puyallup, WATo Pierce County-Thun Field (PLU), Puyallup, WA
- Aircraft age
- About 5 years (built 2012)
- 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 oper/perf/capability
- Aircraft › Aircraft systems
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The private pilot stated that, during the landing roll, the right brake of the experimental amateur-built airplane failed. The airplane subsequently departed the runway and impacted an airport fence, resulting in substantial damage. The airplane was equipped with a castering nosewheel and steering was accomplished through differential brake pressure; therefore, the pilot did not have any other means to either stop the airplane or maintain directional control once it had slowed to a speed below which rudder authority was available.
Postaccident examination revealed that the right brake disc had detached from the wheel hub. None of its attachment bolts were found, and the attachment bolts on the left brake disc were loose. The bolts and discs had holes to accommodate safety wires, but no safety wires were found on either assembly.
The pilot had recently purchased the airplane following the completion of a condition inspection. Before the inspection, the airplane's builder had adjusted the landing gear, which necessitated removal of the brake discs. The builder could not recall using safety wires to secure the brake discs during the reinstallation, and the mechanic who performed the subsequent inspection also could not recall if safety wires were used.
Probable cause
The airplane builder's failure to install safety wires on the brake disc attachment bolts, and the mechanic’s failure to identify the omission during the condition inspection. The subsequent brake disc separation resulted in a loss of directional control during the landing roll.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR17LA114
- Event ID
- 20170531X93750
- Case number
- WPR17LA114
- 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: 0bb6b3f099457bb7f41481f15512ee8eb5913605c5f25fa3f7e8f37949f01cfd; retrieved 2026-09-16T05:21:04.908Z.