What happened
On September 8, 2024, at approximately 12:07 CST, a Zenith Zodiac CH601, registration N9853M, was destroyed during an accident near Columbia, Illinois. The aircraft was being operated under 14 CFR Part 91 for a personal flight.
The flight was a maintenance test flight returning to Sackman Field Airport (IL9 overlap 91) after the pilot noticed an apparent oil leak. According to the pilot, the smell of oil was present and smoke began filling the cockpit. In an attempt to restore visibility, the pilot opened the cockpit canopy during the approach, which resulted in a loss of control.
The aircraft impacted a flat agricultural field approximately 0.3 nautical miles northwest of the approach end of runway 21. Surveillance footage captured the aircraft impacting the field in a nose-high, upright configuration before pitching nose-over and coming to rest inverted. A post-impact fire occurred, causing the engine compartment, forward fuselage, and cockpit to be fully engulfed. The pilot sustained one serious injury and was able to use an onboard fire extinguisher until witnesses arrived to assist with his extraction from the wreckage.
The investigation
Investigators examined the debris path, which extended approximately 60 feet on a heading of 140° to the main wreckage. The engine compartment, fuselage, and the inboard sections of both wings exhibited extensive thermal damage due to the post-crash fire.
Mechanical examination confirmed that flight control continuity and engine power control were intact. The engine, an experimental Aero Momentum inline four-cylinder, normally aspirated engine, showed several holes in the engine case and oil pan. This damage was consistent with a damaged piston assembly.