Accident Overview
On September 13, 2017, at approximately 1717 central daylight time, a Cessna 210G airplane, registration N5906F, was substantially damaged during a forced landing following a loss of engine power near Hallsville, Missouri. The private pilot, the sole occupant, was not injured. The airplane was registered to and operated by AWG Aviation LLC under Title 14 Code of Federal Regulations Part 91 as a personal flight. Day visual meteorological conditions prevailed, and the flight operated without a flight plan.
Flight Details
The flight departed Columbia Regional Airport (COU) in Columbia, Missouri, at about 1704, with a destination of Washington Municipal Airport (AWG) in Washington, Iowa. After climbing to 3,500 feet above mean sea level, the pilot leaned the engine's mixture. While in cruise flight, the pilot observed a total loss of engine power, with the propeller continuing to windmill. The pilot made unsuccessful attempts to restart the engine and subsequently performed a gear-up landing in a cornfield, which resulted in damage to the fuselage.
Postaccident Examination
A Federal Aviation Administration inspector conducted a postaccident examination of the airplane. The examination revealed that the engine mixture control cable had fractured approximately nine inches from its attachment point at the engine. The cable was sent to the National Transportation Safety Board (NTSB) Materials Laboratory for further analysis.
Microscopic Analysis
Digital microscope images of the wire strands showed that the fracture surfaces were flat and perpendicular to the axes of the strands. No necking or thinning of the individual strands, consistent with overstress separation, was observed. Several wires were sectioned and examined using a Zeiss Auriga 40 field emission scanning electron microscope (SEM). Post-separation impact damage was observed around the outer circumference of the fracture surface. Feathery features consistent with fatigue were observed on the fracture surface.
The full NTSB Materials Laboratory report is available in the official docket of this investigation.