What happened
On January 16, 2026, at approximately 11:30 CST, a Cessna 172K, registration N79118, was conducting a maintenance test flight under 14 CFR Part 91 near Amery, Wisconsin. The flight was being performed following a complete overhaul and reinstallation of the Lycoming O-320-E20 engine.
While circling Amery Municipal Airport, the pilot experienced a loud bang and violent airframe vibrations, accompanied by a partial loss of engine power. The pilot attempted to reenter the traffic pattern for runway 36. As the aircraft transitioned to the base leg, the engine suffered a total loss of power.
Realizing the aircraft could not reach the runway, the pilot performed a forced landing in a snow-covered field. During the landing rollout in the snow, the aircraft nosed over, causing substantial damage to the fuselage and both wings. The pilot was not injured.
The investigation
A mechanic reported that no issues were observed with the engine during ground testing prior to the maintenance flight. The aircraft was retained for further examination.