The pilot reported that shortly after transition to cruise flight, he noticed the engine was "running rough," the Cylinder Head Temperature was almost in the red, and the needles showed decreasing performance on the Tachometer and the Manifold Pressure Gauges. He decided to return to the departure airport for a precautionary landing. On approach, he decreased the engine power setting, increased the mixture and propeller settings and the airplane crossed the runway threshold about 80 knots with full flaps. During the flare, the airplane "dropped," landed hard, and bounced three times on the runway. He taxied off the runway and was towed back to the ramp.

The airplane sustained substantial damage to the fuselage.

The Federal Aviation Administration inspector reported that no mechanical failures or malfunctions were found during their investigation.

The automated weather observation station located on the airport reported that, about the time of the accident, the wind was variable at 4 knots. The airplane landed on runway 33.