EASA SIB 2019-10R1
Power Turbine Over-Speed Protection on ARRIEL 2D and ARRIEL 2B1 Engines
Summary
EASA Safety Information Bulletin 2019-10R1 is an airworthiness bulletin addressing power turbine over-speed protection on ARRIEL 2D and ARRIEL 2B1 engines installed on AS 350 B3 and EC 130 T2/B4 helicopters. It provides information on the design and safety features related to turbine blade shedding to prevent turbine disc burst and introduces electronic over-speed protection via FADEC software and wiring modifications. The bulletin includes references to Airbus Helicopters and SAFRAN service bulletins supporting these modifications.
What Changed
This revision of EASA SIB 2019-10 expands the applicability to include helicopters equipped with ARRIEL 2B1 engines and updates references to Airbus Helicopters and SAFRAN service information. It also introduces modification 0720015, which simplifies a previous modification for helicopters with ARRIEL 2D engines by integrating a shunt harness. The bulletin provides an updated list of approved modifications and associated service bulletins.
Why It Matters
This bulletin is important for aviation professionals because it addresses the risk of turbine over-speed and potential post-impact fires caused by blade shedding in ARRIEL 2 series engines. Operators and maintenance organizations need to be aware of the new electronic over-speed protection to enhance safety and reduce the likelihood of fire following an accident. Understanding and implementing these modifications helps ensure continued airworthiness and operational safety of affected helicopters.
What To Do
EASA recommends that operators of AS 350 B3 and EC 130 T2/B4 helicopters equipped with ARRIEL 2D or 2B1 engines incorporate the applicable engine and helicopter modifications as detailed in the referenced Airbus Helicopters and SAFRAN service bulletins. Although no mandatory compliance deadline is specified, timely implementation is advised to mitigate safety risks. For further technical information, operators should contact Airbus Helicopters or SAFRAN technical representatives.