After takeoff for an instructional flight, when the Cessna 172 reached 1,800′ mean sea level, the student pilot began a left turn toward the destination.
Shortly after, the engine went silent and stopped producing power.
The flight instructor took control, slowed the airplane, and landed into the wind on a gravel road near Algona, Iowa.
During the landing roll, the left wheel caught the edge of the road, and the airplane veered into a ditch, which resulted in substantial damage to the wing and fuselage.
Examination revealed that the engine’s No. 1 cylinder head had separated at the cylinder head-to-barrel interface.
The engine had accumulated 605.9 hours since the last engine overhaul, which was conducted over 23 years before the accident. The engine manufacturer’s recommended time between overhaul for the accident engine was 1,800 hours or 12 years.
However, it could not be determined if the lack of an overhaul within the manufacturer’s recommended overhaul period led to the No. 1 cylinder head separating at the cylinder head-to-barrel interface.
Probable cause: The No. 1 cylinder head separating at the cylinder head-to-barrel interface and the subsequent total loss of engine power.
NTSB Identification: CEN18LA051
This December 2017 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.