Republic RC3 N6490K accident near Post Oak, Missouri

Probable cause

A partial loss of engine power due to low cylinder compression. Contributing to the loss of engine power was rust formation in the cylinders due to inactivity.

NTSB analysis

The private pilot was conducting a local flight when the airplane's engine started to lose power. The pilot attempted a forced landing to a field; however, the airplane collided with trees. Examination of the airplane's engine noted that compression was low in all cylinders, and rust was present inside the cylinders. The airplane was not operated for about 4 years and had flown about 2 hours since being returned to service. The partial loss of engine power is consistent with a degradation in cylinder compression, and it is likely that rust formed in the engine during the time the airplane was not being used.

Text from the NTSB. Open the NTSB docket for CEN16LA355 for the full record.