Sikorsky continues to investigate new markets for its X2 compound coaxial helicopter technology following the loss of its recent protest appeal to the U.S. Government Accountability Office (GAO) of the U.S. Army’s Future Long Range Assault Aircraft (FLRAA) award to Bell. In February, Sikorsky unveiled plans to potentially offer an aircraft positioned between the Raider-X, its ongoing effort to compete in the Army’s Future Attack and Reconnaissance Aircraft program, and the Defiant-X design it proposed for the FLRAA in partnership with Boeing.
Sikorsky would offer the helicopter in a utility configuration and as a possible eventual replacement for the NH Industries Airbus/Leonardo joint venture fly-by-wire twin NH90. The OEM unveiled its multi-role “International Twin” concept at Defense IQ’s international military helicopter conference in London earlier this year and again at the Helicopter Association International's Heli-Expo in Atlanta in March.
Paul Lemmo, Sikorsky CEO and president, said the company targets the international utility market for the twin-engine International Twin and that it was working collaboratively with Leonardo on a study involving the design for the Italian government to see how X2 “fits into their [NATO’s] next-generation helicopter program.” Sikorsky also is “closely watching” the “next generation rotorcraft capability” requirement under development by NATO. “We certainly think that X2 fits very well with a number of requirements they have and we will continue to work on that as time moves on. There’s a lot going on with X2 even though we did not have a positive decision on the FLRAA program.”
NATO announced the Next Generation Rotorcraft Capability (NGRC) project—a collaboration between the defense departments of France, Germany, Greece, Italy, and the UK—in November 2020. NATO has set a target for the NGRC to enter service as NH-90s retire beginning in 2035. Subsequently, the Netherlands also joined the program. Spain and the U.S. joined as observers. As currently constituted, the program envisions a production run to last to at least 2059 with three major block changes along the way. Several major feasibility studies have begun. Broad goals for the program include a unit cost not to exceed $37 million each, an open systems architecture, and an availability rate not below 75 percent.
Along with Sikorsky’s X2 technology, the design of the compound Airbus Racer (rapid and cost-efficient rotorcraft) technology demonstrator could also find its way into the mix of possible technologies. Plans call for the Racer to make its first flight later this year. Airbus designed the aircraft to cruise nearly twice as fast as a conventional helicopter, at cruise speeds of up to 220 knots. The design stems from the European Commission's H2020 research program as part of the Clean Sky 2 initiative. A pair of 2,500-shp Safran Aneto-1X engines that provide 25 percent more power the similar-sized engines would power it. The Racer can achieve up to a 15 percent reduction in fuel burn when one of the two engines is placed in standby mode during cruise flight, a configuration Safran calls "Eco Mode." The design features two pusher propellers mounted to a fixed tandem wing and a five-bladed main rotor. The wings provide additional vertical lift and the ability to fly farther and faster than conventional helicopters. Airbus developed the Racer from its retired X3 technology demonstrator, which achieved a top forward speed of 255 knots.
While improvements have been made, dissatisfaction with the fly-by-wire NH90 continues. In 2019, Germany temporarily grounded all of its pre-2018 production NH90s due to tail rotor problems. In 2021, Australia decided to ditch its fleet of marinized NH-90s, designated MRH90, a decade ahead of schedule due to chronic parts availability and maintenance issues. Last year Norway terminated its contract to acquire 14 NH90 medium-lift helicopters it intended to use for coast guard patrol and anti-submarine warfare missions. Citing 20 years of frustration with the NH90 helicopter program, the Norwegian government additionally requested a full refund from NHIndustries.The program began in 1995 and delivered its first helicopter in 2007. According to the company website, it delivered 471 units across 20 different variants to a variety of armed forces, primarily in Europe. The twin-engine helicopter features fly-by-wire flight controls, a useful load of 9,260 pounds, a maximum speed of 162 knots, and a range of 530 nm. It was designed to provide a European-made alternative to Sikorsky’s ubiquitous UH-60 Black Hawk.
While NATO appears eager for an NH90 replacement, given the GAO’s harsh critique of Sikorsky’s FLRAA protest, the company will need to do some convincing to become a player with its International Twin in the NGRC. The agency faulted the helicopter maker for failing “to provide the level of architectural detail required by the [request for proposal].” Nevertheless, Sikorsky’s Lemmo remains optimistic about X2 technology and the prospects for the International Twin. “We believe this delivers revolutionary capability in speed, range, maneuverability, and survivability,” he said.