What happened
On June 30, 2024, an instructor and a student pilot were conducting an IFR training flight involving procedures and a landing at EPMO. The flight was operated using a Tecnam P2006T, registration SP-LFA, belonging to Polska Akademia Lotnicza Sp. z o.o.
During the return flight to EPPT, at an altitude of approximately 3,000 ft AMSL, the cylinder temperature (CT) of the left engine rose above the permissible limit of 120°C. Following standard operating procedures (SOP) for abnormal/emergency situations, the crew shut down the left engine and decided to continue the flight to EP其PT.
At approximately 11:15, a low coolant level warning appeared on the Crew Alerting System. The crew executed the appropriate emergency procedures and declared a PAN PAN urgency signal to FIS Warszawa. The crew also notified the EPPT airport information service of their intention to land. Air traffic controllers secured the airport and separated other traffic to facilitate the arrival. The aircraft landed at EPPT at 11:47 without further incident.
The investigation
The investigation focused on the cause of the temperature increase and the subsequent loss of coolant. Upon inspection and disassembly of the cooling system pump, investigators identified a failure in the pump shaft seal.
Findings
- The primary cause of the event was a leak in the cooling system, which led to the rise in the left engine's cylinder temperature.
- The failure was attributed to the natural wear of the rubber sealing ring on the pump shaft, which resulted in the leakage of coolant.