ERA13LA327 · Univair Aircraft Corporation 108-1
Univair Aircraft Corporation 108-1 · Accident: loss of engine power (total) en route
From 5M3 · Moultonboro, NH to Mountain View Field (NH31)
Event
- NTSB case
- ERA13LA327
- 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
- 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
Univair Aircraft Corporation 108-1
- Aircraft type
- Univair 108
- 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
- N8721K
- Operator
- Fawcett Walter L
- Onboard fatalities
- Unknown
- Route
- From 5M3 · Moultonboro, NHTo Mountain View Field (NH31), Wolfeboro, NH
- 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
- 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
- Personnel issues › Action/decision
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
About 7 minutes after takeoff and while leveling off the airplane at 1,800 ft, the pilot leaned the fuel-to-air mixture, and the engine immediately began to run roughly. The more experienced right-seat pilot took control of the airplane and attempted to restore power, but his attempts were unsuccessful. The propeller continued to rotate briefly but then stopped. The pilot maneuvered the airplane for a forced landing in a field, and the airplane subsequently impacted a raised concrete culvert.
Postaccident examination of the engine revealed that the crankshaft was fractured. Metallurgical examination of the crankshaft revealed evidence of fatigue cracking that had originated from circumferential gouges at the aft radius of the R2 rod journal. A review of engine records revealed that, about 45 years before the accident, the crankshaft was replaced during an engine overhaul and that the main and connecting rod bearing journals were ground 0.010-inch undersize. About 7 years before the accident, the engine was overhauled again, and the crankshaft main and connecting rod bearing journals were polished. The engine was installed in the accident airplane about 3 years before the accident; the engine failure occurred about 115 hours after the engine's last overhaul. It is likely that, if maintenance personnel had detected and removed the circumferential gouges at the aft radius of the R2 rod journal during the engine's last overhaul, the fatigue cracking would not have started and the crankshaft would not have failed.
Probable cause
Maintenance personnel’s failure to remove circumferential gouges in the aft radius of the R2 rod journal on the crankshaft during its last engine overhaul, which resulted in the fatigue failure of the crankshaft and a subsequent total loss of engine power.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record ERA13LA327
- Event ID
- 20130719X52759
- Case number
- ERA13LA327
- 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. 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: ba6734c4dba228e691dced4d954f8cc23f0e352b9d722358f0aaad4088a74fa5; retrieved 2026-09-15T22:15:10.277Z.