Airbus Helicopters has unveiled the aerodynamic configuration of the high speed demonstrator it is developing as part of the Clean Sky 2 European research programme.

Codenamed Racer, for Rapid And Cost-Effective Rotorcraft, this demonstrator will incorporate a number of innovative features and will be optimised for a cruise speed of more than 400km/h.

The company says the project will aim at achieving the best trade-off between speed, cost-efficiency, sustainability and mission performance. Final assembly of the demonstrator is expected to start in 2019, with a first flight the next year.

The Racer demonstrator will be built around a simple architecture, ensuring safety and cost-efficiency. New features not seen on earlier illustrations of the concept include an innovative “box-wing” design, optimised for aerodynamic efficiency, to provide lift in cruise mode while isolating passengers during ground operations from the lateral rotors designed to generate thrust in forward flight.

Other new features include the "pusher" configuration of the lateral rotors and an asymmetrical tail boom for enhanced hover performance.

Optimised for performance and low acoustic signature, these lateral rotors as well as the main rotor will be driven by two RTM322 engines. An “eco mode” will be tested by the engine manufacturer to demonstrate an electrically-powered “start and stop” of one engine in flight, thus generating fuel savings and increasing range.

The Racer demonstrator will also benefit from a hybrid metallic-composite airframe, specifically designed for low weight and low recurring costs. It will also be equipped with a new high voltage direct current electrical generation, which will significantly contribute to weight reduction.

Building upon the success of the self-funded X3 demonstrator, which validated the “compound” aerodynamic configuration – a combination of a traditional main rotor and innovative lateral rotors – the Racer project aims to bring this concept closer to an operational design and demonstrate its suitability for a wide spectrum of missions where increased speed and efficiency will bring added value for citizens and operators.