ERA23LA361 · Beech V35
Beech V35 · Accident: loss of engine power (total) en route
From Gatlinburg-Pigeon Forge Airport (GKT) to Tucker Guthrie Memorial Airport (I35)
Event
- NTSB case
- ERA23LA361
- 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
Beech V35
- Aircraft type
- Beechcraft 35
- 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
- N5431U
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Gatlinburg-Pigeon Forge Airport (GKT), Sevierville, TNTo Tucker Guthrie Memorial Airport (I35), Harlan, KY
- Aircraft age
- About 56 years (built 1967)
- 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
- En route · cruise
- 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 engine power (total)
- 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 power plant
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot reported that he was about 15 minutes into the cross-country flight when the engine made a “loud bang,” began to run rough, and eventually seized. Unable to glide to an open field, the pilot conducted a forced landing into trees. He and his passenger were not injured; however, the airplane was substantially damaged. Examination revealed several holes in the engine case, and one of the No. 2 crankshaft cheek counterweights was missing. Further examination revealed two of the counterweight retaining circlips were fractured. Examination of the fractured circlips revealed that one of the circlip legs failed from fatigue crack propagation. The engine had been disassembled and the crankshaft inspected due to a propeller strike about 130 operating hours before the accident.
Probable cause
A total loss of engine power due to the fatigue failure of a retaining circlip in one of the No. 2 crankshaft cheek counterweights, which resulted in liberation of the counterweight.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ERA23LA361
- Event ID
- 20230905193000
- Case number
- ERA23LA361
- 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, 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: c05e238aa5b8c04f4a46b6178451121221de909d7f84291ed5a4ef1dcf23b975; retrieved 2026-09-16T18:05:01.989Z.