CHI94LA315

Approximately two hours into the flight, the pilot reported he heard a loud bang. The windshield became covered with oil, the airplane shook violently, and the cockpit filled with smoke. The pilot prepared for a forced landing. While attempting to land on a road, the airplane collided with utility wires. It then impacted the ground and struck a road sign and a telephone pole before coming to rest. A postaccident examination revealed the number two cylinder connecting rod had failed. The connecting rod was sent to the NTSB materials laboratory in Washington, d.c., for further examination. The laboratory reported the fractures of the components submitted appeared to have features which are representative of overstress separations or cyclic stress. There was no evidence of fatigue from normal operations.

On September 8, 1994, at 1100 central daylight time, a Mooney M20C, N9310V, was destroyed following a loss of engine power and subsequent forced landing near Hanston, Kansas. The pilot reported minor injuries, the one passenger aboard reported no injuries. The personal 14 CFR Part 91 flight originated from Denver, Colorado, at 1020 mountain standard time on a VFR flight plan with an intended destination of Wichita, Kansas. Visual meteorological conditions prevailed at the time of the accident.

In a written statement, the pilot reported he heard a loud bang approximately two hours into the flight. The windshield became covered with oil, the airplane shook violently, and the cockpit filled with smoke. The pilot stated he prepared to make a forced landing. Due to the obstructed view of the windshield, the passenger opened his door to view forward in order to help guide the pilot towards the selected landing area. While attempting to land on a road, the airplane collided with utility wires. The airplane impacted the ground and struck a road sign and a telephone pole before coming to rest.

A postaccident examination by an FAA Inspector revealed the number two cylinder connecting rod had failed. Further examination of the magnetos, oil pump, and induction system indicated normal operation.

Sections of the failed connecting rod, piston, and pin were sent to the NTSB Materials Laboratory, Washington, D.C., for further examination. A large portion of the rod and bolt were not able to be found at the accident scene for examination. The laboratory reported the fractures of the components submitted appeared to have features which are representative of overstress separations or cyclic stress above the yield of the material. None of the components which were submitted contained fractures indicating the primary initiating break of the assembly. There was no evidence of fatigue cracking from normal operation.