SEA02LA074 · Stinson 108-2
Stinson 108-2 · Accident: airframe, component or system failure during takeoff
From Helena Regional Airport (HLN) to Helena Regional Airport (HLN)
Event
- NTSB case
- SEA02LA074
- 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
Stinson 108-2
- Aircraft type
- Stinson 108
- 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
- N959D
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Helena Regional Airport (HLN), Helena, MTTo Helena Regional Airport (HLN), Helena, MT
- 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
- Takeoff · roll/run
- First occurrenceThe 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
- Airframe, component or system 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
- Landing gear, wheel › Fractured
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot reported that shortly after applying power for takeoff, the airplane started to track left of runway centerline. During his attempts to correct the situation, the airplane's right main wheel assembly and right landing gear strut collapsed. Post-accident examination of the wheel assembly and tire installed on the accident airplane revealed that the outboard wheel subassembly fractured in multiple locations along the bead seat ring. Multiple fractures were observed in the inboard wheel subassembly, and the brake disc had partially separated from the wheel. The Type Certificate Data Sheet for the airplane lists multiple approved wheel-brake assemblies for the aircraft. The wheel assembly found on the airplane is not listed as one of the approved installations, and the wheel assembly was not approved for use with tires larger than size 7.00-6. The accident airplane was equipped with 8.00-6 size tires. The airplane's last inspection, an annual inspection, was performed on March 7, 2002.
Probable cause
Fracture of the left main wheel assembly during the takeoff roll. Factors include the use of a wheel assembly not approved for the accident airplane, and the use of an oversized tire.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA02LA074
- Event ID
- 20020426X00585
- Case number
- SEA02LA074
- Dataset
- historical-pre2008
- Source SHA-256
- 89e2df6d848e7ab3b42e7d7c7a03ff403303057a26ca04c95b3ea67201c3ce74
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: 3105bde3995354162a5aa9cdad153bf42e33966eae664618762cd7d2d0d5afa5; retrieved 2026-09-22T10:59:42.083Z.