Probable cause
The improper torque of the engine’s No. 3 cylinder intake pipe bolts, which resulted in the separation of the pipe and a partial loss of engine power.
NTSB analysis
The private pilot stated that, during an en route climb to cruise altitude, the engine began to vibrate and the engine fuel flow decreased. The pilot initiated a return to the departure airport during which the airplane was unable to maintain altitude. The pilot performed a forced landing to a cornfield, resulting in substantial damage. Postaccident examination of the engine revealed that the No. 3 cylinder intake pipe was loose and missing its attachment bolts. Review of maintenance logbooks showed that the No. 3 engine cylinder intake pipe gasket was replaced about 400 flight hours before the accident. It is likely that the bolts were improperly torqued at the time of replacement.
Text from the NTSB. Open the NTSB docket for CEN16LA032 for the full record.
Event
- Date
- Oct 8, 2015
- Type
- Accident
- Place
- Red Oak, Iowa
- Highest injury
- None
- Weather
- Visual (VMC)
- Light
- Day
Cessna 177RG
- N-number
- N1542H
- Category
- Airplane
- Year built
- 1975
- 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.