ATL94LA158 · Cessna 172XP
Cessna 172XP · Accident: total loss of engine power (mechanical failure) en route
From John C Tune Airport (JWN) to OLV · Memphis, TN
Event
- NTSB case
- ATL94LA158
- 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 172XP
- Aircraft type
- Cessna 172
- 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
- N9797V
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From John C Tune Airport (JWN), Nashville, TNTo OLV · Memphis, TN
- 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
- Electrical system, drive/belt › Failure, total
Approximate · Estimated position: the centre of Clarksburg, TN, the place the record names. Not the accident site.
NTSB narrative
WHILE EN ROUTE TO HIS DESTINATION AIRPORT, THE PILOT EXPERIENCED COMPLETE LOSS OF ENGINE POWER. THE PILOT SELECTED A PASTURE AND MADE AN EMERGENCY LANDING. DURING THE ROLLOUT, THE AIRPLANE COLLIDED WITH TREES ALONG A FENCE LINE. EXAMINATION OF THE ENGINE DISCLOSED THAT THE ALTERNATOR DRIVE COUPLING FAILED, AND DEBRIS FROM THE COUPLING LODGED IN THE ENGINE OIL PUMP DRIVE; THE ENGINE EXPERIENCED A LOSS OF ENGINE OIL PRESSURE.
Probable cause
THE FAILURE OF THE ALTERNATOR DRIVE COUPLING, AND DEBRIS FROM THE FAILED COUPLING THAT LODGED IN THE ENGINE OIL PUMP, RESULTING IN A SHEARED OIL PUMP DRIVE SHAFT. THE ENGINE SUBSEQUENTLY FAILED BECAUSE OF OIL STARVATION.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ATL94LA158
- Event ID
- 20001206X01939
- Case number
- ATL94LA158
- 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: f4ed56806fe957174f4dd794616ef03ea392290af216c685ff38ad26c78b139d; retrieved 2026-09-23T00:47:58.120Z.