Safran Helicopter Engines has validated its “Eco Mode” hybrid propulsion system during recent ground tests in Bordes, France, ahead of flight tests later this year on the Airbus Helicopters Racer (rapid and cost-efficient rotorcraft) high-speed, compound helicopter demonstrator. The hybrid electric propulsion mode was tested for the first time in a configuration similar to the one to be used on the Racer.
Designed for twin-engine helicopters, Eco Mode places one engine on standby during cruise flight, while the other operates at a more energy-efficient power setting. This mode reduces fuel consumption and CO2 emissions by about 15 percent and increases the helicopter’s range, according to Safran. The engine is automatically restored to full power within a few seconds, via an electric fast restart system, when landing or during an emergency.
Eco Mode was developed as part of a research project funded by the French civil aviation authority (DGAC). It uses a Safran Aneto-1A engine (2,500 shp) and a fast restart electrical system, developed jointly with Aquitaine Electronique (AECE Group) and Safran Cabin (Ventilation Systems). This system combines electronic engine control with a high-power-density electric motor, mechanically connected to the engine's high-pressure section.