Eurocopter EC 135 P2+ Incident Near Sieraków (SP-HXV)

Incident Overview and Flight Details On 6 February 2017, a Eurocopter EC 135 P2+ was conducting a repositioning flight from Szczecin (EPSC) to Ostrów Wielkopolski (EPOM) under operational order LPR nr 10/OLHXV/2017. The flight was planned along the route EPSC-EPPO-EPOM. The first leg from Szczecin to Poznań (EPPO) was conducted under instrument flight rules (IFR) to maintain the crew's instrument qualifications, while the second leg from Poznań to Ostrów Wielkopolski was conducted under visual flight rules (VFR). ## Event Description After departing Szczecin, the crew climbed to 3,000 meters while heading toward Poznań. In the vicinity of Sieraków, the crew began a VOR DME descent procedure on the heading of runway 10, without the intention of landing. During a maneuver to level off from the descent while turning right toward the course for Ostrów Wielkopolski, the pilot observed a yellow highlighting of the engine shaft torque values on the FLI display, indicating an exceedance of the allowable torque (TRQ) limits. ## Crew Response and Aftermath The pilot responded by reducing the collective pitch and power using the collective and power levers. With normal indications restored, the crew continued the flight to the destination. The landing at Ostrów Wielkopolski was uneventful. ## Investigation Findings Analysis of the UMS/PGS system records confirmed a torque exceedance on the right engine shaft. The TRQ exceedance reached 77.4% for a duration of 2.125 seconds. In accordance with procedure MSM 05-51-00,6-8, the exceedance was classified as Category B and required maintenance action within 5 flight hours. ## Maintenance Actions On 7 February 2017, technical personnel from SOT Szczecin performed the required maintenance, including inspections of the oil filter, main and fenestron gearbox chip detectors, and the main rotor hub. A ground test was subsequently conducted, and the helicopter was found to be serviceable. ## Probable Cause and Safety Actions The probable cause of the right-engine torque exceedance was identified as overly aggressive use of the flight controls during the entry into the descent maneuver with a simultaneous right turn toward the approach path for Poznań. The operator informed LPR operational personnel of the incident. The State Commission for Aviation Accident Investigation (PKBWL) did not issue any safety recommendations.