Probable cause
A failure of the No. 1 piston pin plug due to corrosion in the cylinder barrel, which resulted in oil contamination, oil starvation to the crankshaft connecting rod bearings, and a subsequent partial loss of engine power.
NTSB analysis
The private pilot stated that the engine experienced a partial loss of power shortly after takeoff on the local flight. In an effort to regain power, the pilot switched fuel tanks, applied carburetor heat, and richened the fuel mixture, but the engine continued to operate at reduced power. The pilot attempted to land at a nearby airport; however, he overshot the runway and decided to perform a forced landing to an adjacent cornfield. During the landing, the right wing impacted the corn, and the airplane came to rest upright.
Partial disassembly of the engine revealed a failure of the No. 1 piston pin plug due to corrosion in the No. 1 cylinder barrel. The plug failure resulted in significant oil contamination and subsequent oil starvation and damage to the crankshaft connecting rod bearings. The damage to the bearings resulted in the partial loss of engine power.
Text from the NTSB. Open the NTSB docket for CEN17LA006 for the full record.
Event
- Date
- Oct 4, 2016
- Type
- Accident
- Place
- Wilmot, Wisconsin
- Highest injury
- None
- Weather
- Visual (VMC)
- Light
- Day
Cessna 172K
- N-number
- N46377
- Category
- Airplane
- Year built
- 1968
- Damage
- Substantial
- Operating rule
- Part 91 (general aviation)
- Purpose of flight
- Personal
From the NTSB aviation accident database: N-registered aircraft, events since 2008, data through Oct 28, 2026. The file is published monthly, so the latest weeks are incomplete and recent records can change. The official source is the NTSB aviation investigation search. CheckAero is independent and not affiliated with the NTSB.