CHI89LA063 · Beech 95-B-55
Beech 95-B-55 · Accident: total loss of engine power (mechanical failure) en route
From BQM · Louisville, KY to BQM · Louisville, KY
Event
- NTSB case
- CHI89LA063
- 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
Beech 95-B-55
- Aircraft type
- Beechcraft 95
- 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
- N27WF
- Operator
- Casebolt, Fon · private individual
- Onboard fatalities
- Unknown
- Route
- From BQM · Louisville, KYTo BQM · Louisville, KY
- 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
- En route · cruise
- 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
- Total loss of engine power (mechanical 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
- Eng assembly, crankshaft counterweights/vib damper › Failure, total
- Powerplant › Failure, total
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
DURING A LOCAL PLEASURE FLIGHT, WHILE IN NORMAL CRUISE, THE RIGHT ENGINE FAILED TOTALLY. THE PILOT REDUCED POWER ON THE LEFT (OPERATING) ENGINE TO 'CURTAIL THE VIOLENT VIBRATION OF THE AIRCRAFT' AND EXECUTED A FORCED LANDING IN AN OPEN FIELD. AS THE AIRCRAFT WAS ROLLING OUT AFTER TOUCHDOWN, IT ENCOUNTERED A MUDDY AREA. THE NOSE GEAR BOGGED DOWN, THEN COLLAPSED, AND THE AIRCRAFT NOSED OVER. POST-ACCIDENT EXAMINATION OF THE RIGHT ENGINE REVEALED THAT THE PIN RETAINING PLATE CUT THROUGH THE CRANKSHAFT COUNTERWEIGHT, RELEASING IT. FURTHER EXAMINATION REVEALED THAT THE COUNTERWEIGHTS HAD NOT BEEN 'TUFTRIDED', A SURFACE HARDENING PROCESS WHICH PREVENTS THE PIN RETAINING PLATE FROM CUTTING/WEARING THROUGH THE COUNTERWEIGHT. THIS PROCESS HAS BEEN REQUIRED ON NEW ENGINES SINCE 1968, AND ON REBUILT ENGINES SINCE 1973-74. THE ACCIDENT ENGINE WAS REBUILT BY THE MANUFACTURER IN 1971. LOGBOOK/MAINTENANCE INFORMATION PROVIDED BY THE PILOT WAS INCOMPLETE.
Probable cause
A FAILURE OF THE ENGINE DUE TO A CRANKSHAFT COUNTERWEIGHT FAILURE. THE PILOT PERFORMED EMERGENCY PROCEDURES AND EXECUTED A FORCED LANDING IN AN OPEN FIELD, WHERE THE AIRCRAFT ENCOUNTERED A LARGE MUDDY AREA, BOGGED DOWN AND NOSED OVER.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CHI89LA063
- Event ID
- 20001213X27865
- Case number
- CHI89LA063
- 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: fca9d04356587eb708bd0db93f950e80cd6a6dd7f481d2a28de5011da71ed9d6; retrieved 2026-09-22T00:15:45.740Z.