ANC98LA140 · Cessna 140
Cessna 140 · Accident: total loss of engine power (mechanical failure) en route
From Clear Creek Airport (2AK2) to Fairbanks International Airport (FAI)
Event
- NTSB case
- ANC98LA140
- 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
Cessna 140
- Aircraft type
- Cessna 140
- 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
- N81045
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Clear Creek Airport (2AK2), CLEAR CREEK, AKTo Fairbanks International Airport (FAI), AK
- 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
- Engine assembly, valve, exhaust › Fractured
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
While in cruise flight the pilot heard a 'clunk' and engine rpm immediately began to decrease. The engine noise and rpm decrease continued, the pilot performed a forced landing in tundra, and the airplane nosed over onto its back. Postaccident inspection revealed that the exhaust valve stem of the number two cylinder had separated, and the valve was ingested into the cylinder. The engine had accumulated 4,555 hours since new, and 1,089 hours since overhaul.
Probable cause
The loss of engine power due to an in-flight fracture of an engine exhaust valve stem assembly. A factor associated with the accident was the lack of suitable terrain for a forced landing.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ANC98LA140
- Event ID
- 20001211X10973
- Case number
- ANC98LA140
- 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: local date, investigation status. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 1998-09-07.
- API snapshot SHA-256: 38e298ca985f2abc6a3e62ab5b749bd100f9caf98b65be68b0d3aa50e5e30cf1; retrieved 2026-09-22T16:52:22.028Z.