SEA98LA087 · Champion 7GCB
Champion 7GCB · Accident: loss of control on ground/water during landing
From Boise Air Terminal/Gowen Field (BOI) to Friedman Memorial Airport (SUN)
Event
- NTSB case
- SEA98LA087
- 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
- 0
- 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
Champion 7GCB
- Aircraft type
- Champion 7
- 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
- N912CP
- Operator
- Garman, Steven, P. · private individual
- Onboard fatalities
- Unknown
- Route
- From Boise Air Terminal/Gowen Field (BOI), Boise, IDTo Friedman Memorial Airport (SUN)
- 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
- 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
- Loss of control on ground/water
- 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, main gear › Overload
- Landing gear, normal brake system › Failure, partial
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot, flying from the front seat, was aware of a tailwheel shimmy condition prior to the flight. Upon touchdown, the aircraft's tailwheel began to oscillate. Marks on the runway showed tailwheel tire scuffing from the touchdown area and beyond. A second solid scuff mark associated with the left wheel was observed as both scuff marks diverged left of the runway centerline. Post-crash examination revealed that the rear right brake-pedal had disconnected from the connecting rod to the forward right brake-pedal and the disconnection rendered the forward right brake-pedal unusable. The disconnection occurred at the rear right brake-pedal attach eye, and one separation surface was observed to be clean whereas the opposing side was dirty. Cracks were observed inside the attach eye radii, as well as the opposing end of the pedal. The right-main landing gear separated. Examination of the tailwheel assembly revealed that the hexagonal nut which holds the inner lock ring in place had become loose allowing the lock ring to shift. This allowed the two lock ring pins to shear, thus allowing the tailwheel to oscillate or 'shimmy' during roll.
Probable cause
The disconnection of the rear right-main brake pedal from the brake master cylinder, and the overloading of the right main landing gear. A factor was the oscillation of the tailwheel.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record SEA98LA087
- Event ID
- 20001211X10422
- Case number
- SEA98LA087
- 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: 9dc52449c448e9dac8dc3f49f089b7241b21e982e9584f94ce3643eb965fb7b2; retrieved 2026-09-22T17:42:42.973Z.