What happened
On July 7, 2016, a PS 28 Cruiser was prepared for a VFR daytime training flight at Depułtycze Królewskie (EPCD) airport. The crew, consisting of a pilot with a CPL (A) license and a student pilot, completed the engine start, standard checklists, and taxiing to the threshold of runway 19L. Following an engine run-up, all engine parameters initially appeared within normal operating ranges.
However, while positioned at the runway threshold, the crew observed that the cylinder head temperatures for the right cylinders had entered the red zone, reaching 138°C. Shortly thereafter, the left cylinder head temperatures also rose into the red zone, reaching 136°C. In response to the overheating, the pilot immediately shut down the engine, which successfully caused the temperatures to decrease. The aircraft was subsequently towed to a hangar.
The investigation
The investigation, conducted by the operator, examined the engine's cooling system and the circumstances surrounding the temperature spike. Meteorological conditions at the time of the event were found to have no impact on the incident.
Findings
The investigation established that the primary cause of the overheating was a blockage in the engine cooling system's vent line.
Safety action
Following the incident, the engine cooling system was inspected, and the ventilation line was cleared to restore proper functionality.