NYC99LA173 · Cessna 172H
Cessna 172H · Accident: loss of engine power while maneuvering
From Tri-State Airport / Milton J. Ferguson Field (HTS) to Mount Vernon Outland Airport (MVN)
Event
- NTSB case
- NYC99LA173
- 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 172H
- 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
- N3213L
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Tri-State Airport / Milton J. Ferguson Field (HTS), Huntington, WVTo Mount Vernon Outland Airport (MVN), Mount Vernon, IL
- 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
- Maneuvering · turn to landing area (emergency)
- 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 engine power
- Also codedOther events the NTSB coded in the sequence, such as a wire strike after a loss of power. Flight Findings uses them for its kinds of event. Glossary
- Tree(s)
- 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, intake › Other
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
On the day of the accident, maintenance was preformed on the number one cylinder to dislodge a stuck valve. The pilot then refueled the airplane and taxied for departure. Once airborne, the pilot climbed to a cruise altitude of 3,500 feet msl without difficulty. Approximately 45 minutes into the flight, the engine started running rough. The pilot diverted, but before he could complete a successful precautionary landing, there was a total loss of engine power. The airplane crashed into trees. Prior to the engine running 'rough', EGT was indicating 'normal.' After the engine started running 'rough', the EGT dropped to below 'normal.' The EGT sensor was located on the number one cylinder. No anomalies with the engine were found after the accident except for a broken intake valve rocker-arm on the number one cylinder. Examination of the rocker-arm revealed no evidence of fatigue or any other form of progressive crack growth.
Probable cause
A stuck intake-valve on the number one cylinder which resulted in a loss of engine power.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record NYC99LA173
- Event ID
- 20001212X19342
- Case number
- NYC99LA173
- 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: 67ca0f719fe0210fcb2927d9b5c01c7f1bbd811652a166ca7964880f30ba96f9; retrieved 2026-09-21T20:28:38.625Z.