Incident Overview
On June 29, 2020, a Cessna 152, registered as SP-KOG, was engaged in a training flight at Babice Airport (EPBC) for a PPL(A) license. The crew consisted of an instructor and a student. The flight involved circuits on runway 28R. After completing two full circuits and shortly after the third takeoff, the crew noticed abnormal engine operation.
Precautionary Landing
The crew immediately informed the AFIS service on the Babice Informacja frequency of their intention to perform a precautionary landing with the wind on the grass runway 10L. The landing was completed without incident.
Post-Landing Inspection
Following the landing, the instructor conducted an engine run-up. During this test, the engine experienced a drop in RPM exceeding 150 RPM and exhibited vibrations. The detected malfunction was recorded in the aircraft technical log (PDT).
Investigation Findings
The investigation, conducted by the Polish State Commission for Aircraft Accident Investigation (PKBWL), determined the cause of the incident: a cracked porcelain lower spark plug on the second cylinder. No contributing circumstances were identified.
Recommendations
The organization responsible for the investigation (the entity that conducted the initial inquiry) proposed a preventive recommendation: the maintenance organization (AMO) tasked a mechanic to conduct an additional inspection and engine run-up. The Commission accepted this recommendation and did not formulate any additional safety recommendations.