What happened
On February 16, 2021, an air ambulance crew operating from the Warsaw branch of Lotnicze Pogotowie Ratunkowe (LPR) was preparing for a medical mission to Stojadła. The crew began the start-up sequence for the Eurocopter EC135 P3, registration SP-HXR.
After the first engine started normally, the pilot attempted to start the second engine. During this process, the engine RPM stabilized at 14%, failing to increase as expected. The pilot decided to abort the start-up once the exhaust gas temperature (EGT) reached approximately 650°C. After waiting for the right-hand engine compressor RPM to return to zero, the pilot initiated a second start attempt, which was successful. The crew subsequently completed the mission and returned to base without further incident.
Following the flight, a technical review of the aircraft's parameters by the Technical Coordination Center revealed that the maximum allowable turbine exhaust gas temperature had been exceeded, reaching 870°C for a duration of approximately 18.875 seconds. The engine manufacturer, Pratt & Whitney, was notified and recommended a thorough inspection and repair of the engine.
The investigation
The PKBWL examined the flight data and the pilot's actions during the engine start sequence. The investigation focused on the monitoring of engine parameters and the adherence to established procedures for aborted starts.
Findings
- The pilot failed to properly distribute attention during the engine start-up sequence.
- There was insufficient monitoring of the second engine's start progress.
- The pilot did not follow the specific instructions contained in the EC135P3 Flight Manual (FLM) regarding the procedure for an aborted start.
Safety action
- The pilot underwent retraining and a simulator session focusing on aircraft limitations and the specific conditions requiring an aborted start.
- The incident was shared with all operational and technical personnel at Lotnicze Pogotowie Ratunkowe to improve awareness of engine start procedures and regulatory compliance.