CleanSky GRC4: Light helicopter demonstrator with high compression engine

Abstract

In the frame of GRC4, part of Cleansky's Green Rotorcraft ITD (Integrated Technology Demonstrator), Airbus Helicopters has lead the development of a flying Demonstrator based on H120 serial helicopter and fitted with a brand new designed High Compression Engine (HCE = Reciprocating engine using Kerosene). For this Research project, Airbus Helicopters teamed with Partners selected via a Call for Proposal, successful in February 2011, and organized in the Consortium HIPE 440, made of TEOS Powertrain Engineering, France, and AustroEngine GmbH, Austria. In the powerclass related to H120 engines (300 to 400kW), the main advantages of HCE compared to turboshaft are: - Lower Specific Fuel Consumption (minimum 30%, up to 50% depending on mission), - Lower CO2 emission at same level as Specific Fuel Consumption reduction, - Higher performance in hot/high conditions thanks to the superchargers. Power is kept constant up to higher altitude and/or higher ambient temperature, - Lower operating cost (fuel, maintenance and overhaul). The only drawback is the additional mass. Therefore the installed engine mass-to-power ratio has to remain below 0.8kg/kW in order to reach similar or better performance than H/C equipped with turboshaft. After engine tests started in March 2013 – less than 1.5 year after the design start – the Ground tests have been completed in March 2015, and Flight tests are scheduled for H2/2015. This paper will explain shortly why Airbus Helicopters needed a brand new engine for this Demonstrator and give an overview of the achievements until Ground tests: power output, fuel consumption, engine mass-to-power ratio, rotor speed control, cooling system, torque oscillations and engine movements