Safran Helicopter Engines (SHE) believes it will be able to deliver a new powerplant for service entry in the mid-2020s that will use electric power in addition to a standard turboshaft in order to optimise in-cruise performance.
The French manufacturer has already embarked on the first stage of its "hybridisation" strategy with the use of "Eco Mode" on its new Aneto powerplant. For use on twin-engined helicopters, the feature allows one of a pair of engines to be idled during flight and then rapidly restarted as required.
Eco Mode will debut on the Aneto-1X, which Airbus Helicopters today revealed will power its Racer high-speed demonstrator.
The Racer, a twin-engined compound rotorcraft, is being produced under the EU's Clean Sky 2 programme and is expected to make its first flight in 2020.
However, Bruno Bellanger, executive vice-president of programmes at SHE, says the next stage will be to add "transitory assistance" to its turboshafts.
"Today, as you know, engines are designed to be very efficient for high-power usage – specifically for take-off and emergency mode," he says. "By combining electrical and thermal power we will be in a position to optimise the system and turbine to deliver some very impressive fuel savings."
Bellanger sees electrical power – probably a combination of a generator and batteries – being able to provide additional power during the cruise phase of flight.
SHE should be in a position to conduct demonstration flights by about 2020, says Bellanger, with a product available for market – depending on airframer demand – by the middle of that decade.
A third strand of hybridisation is also being pursued, designed to tap into the market for a new generation of light eVTOL aircraft requiring electrically powered, distributed propulsion.
However, although SHE sees that emerging market as "very promising", Bellanger cautions that all-electric power is unlikely to usurp the traditional turboshaft engine for any aircraft performing a mission longer than 30min with a payload greater than 100kg (220lb) "for at least two decades".
SHE launched the 2,500-3,000shp (1,860-2,240kW) Aneto engine family in October 2017, with the initial application on the K-model variant of the Leonardo Helicopters AW189, providing an alternative to the baseline GE Aviation CT7 engines.
Leonardo's solitary flight-test aircraft has now accumulated 500h across 70 flights, says Bellanger; service entry is scheduled for later this year.
Elsewhere, flight tests of the Arrano powerplant for the Airbus H160 "are close to the end", he says. So far, the six test engines equipping three flying prototypes have amassed about 1,000h. Certification for the 1,300shp turboshaft is scheduled by year-end.