CEN19LA066 · Piper PA-32R-300
Piper PA-32R-300 · Accident: powerplant system/component malfunction/failure on approach
From Lenawee County Airport (ADG) to Lenawee County Airport (ADG)
Event
- NTSB case
- CEN19LA066
- 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
Piper PA-32R-300
- Aircraft type
- Piper PA-32
- 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
- N8892E
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Lenawee County Airport (ADG), Adrian, MITo Lenawee County Airport (ADG), Adrian, MI
- Aircraft age
- About 43 years (built 1976)
- 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
- Approach · VFR pattern final
- 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
- Powerplant system/component malfunction/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
- Aircraft › Aircraft power plant
- Personnel issues › Experience/knowledge
- Personnel issues › Task performance
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The pilot was performing a flight with an inspection authorization (IA) rated mechanic, who had performed a recent annual inspection of the airplane. During approach to the airport, the engine lost total power. The airplane impacted a fence and terrain short of the runway and sustained substantial damage. Postaccident examination of the engine revealed that the crankshaft gear bolt fractured. Metallurgical examination of the bolt revealed features consistent with fatigue cracking that initiated at multiple sites near the bottom of a thread root. These smaller cracks coalesced and propagated inward through more than half the crack section of the bolt. The bolt began to cycle under reverse bending, which initiated fatigue cracking at multiple sites along the thread root on the opposite side.
The airframe and powerplant (A&P) mechanic who performed a recent overhaul of the engine stated that the engine was the first of the "big" Lycoming engines that he had overhauled. The A&P mechanic stated that he did not like using the Lycoming manuals because they were hard to follow. He mentioned several times that he had contacted Lycoming to request assistance, and they worked with him in providing the necessary documentation needed for the work he was doing. The A&P mechanic stated that he did not torque the crankshaft gear bolt to the engine manufacturer's specifications. The engine overhaul was signed off by the A&P mechanic, and he stated that the IA mechanic just removed and reinstalled the engine onto the airplane. Regulatory requirements state a certificated mechanic may not supervise the maintenance, preventive maintenance, or alteration of, or approve and return to service, any aircraft or appliance, or part thereof, for which he is rated unless he has satisfactorily performed the work concerned at an earlier date.
Probable cause
The airframe and powerplant mechanic's lack of experience in the overhaul of the engine model and the improper torque of the crankshaft gear bolt, which resulted in fatigue failure of the bolt and a total loss of engine power during an approach for landing.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN19LA066
- Event ID
- 20190113X85423
- Case number
- CEN19LA066
- 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, coordinates. 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: c1529f0a5fb3de8eaa678995139b8791c87be0923f8633b1ef022f968fb296aa; retrieved 2026-09-16T08:32:40.381Z.