What happened
The pilot was conducting agricultural application operations, commonly referred to as swath runs, when the propeller experienced an unexpected surge. Following this event, the pilot initiated a return to the airport for landing. During the approach, the engine ceased operation entirely. The aircraft was subsequently landed in a plowed field adjacent to the airfield.
The investigation
Upon landing, the pilot conducted a visual inspection of the aircraft and its powerplant. The examination revealed that the threads on the oil filter adapter had failed structurally. This failure caused the oil filter to separate completely from the engine mount. As a direct result of this separation, the engine lost all of its lubricating oil.
Findings
The mechanical failure was identified as the primary factor in the loss of power. The oil filter adapter thread failure led to total oil exhaustion. The lack of lubrication caused the engine to quit during flight. The aircraft sustained substantial damage to the right wing and landing gear due to the hard landing in the field. No injuries were reported.
Safety message
Regular inspection of engine mounting hardware and oil system components is critical to prevent in-flight power loss. Ensuring that all adapter threads are secure can help avoid catastrophic oil leaks.