A senior Safran Helicopter Engines executive called 2019 “a fantastic year” and said that the company was “working very hard” on projects and programs in 2020, including eVTOL power systems. Bruno Bellanger, Safran Helicopter Engines executive vice president for programs, noted that the company certified four engines in 2019, a feat “never seen in our company in the last 20 years.” Those programs included engines for the Airbus Helicopters H160, Leonardo AW189, Indian Light Utility Helicopter (LUH), and Avicopter AC352, the Chinese variant of the Airbus H175.
The Arrano 1A engine for the Airbus H160 received EASA type certification in June after a test campaign that included more than 11,000 run hours and 2,500 flight hours. The Arrano is a new-generation engine designed to power four- to six-tonne helicopters and produces between 1,100 and 1,300 shp. Engine features include new-generation digital controls and an efficient two-stage compressor with new variable inlet guide vanes. The components Improve engine thermal efficiency and yield a fuel burn that is up to 15 percent lower than comparable in-service engines, Belanger said. The "gyratory" combustion chamber uses fuel injectors made with additive manufacturing techniques (3D printing). The Arrano 1A was designed to be more easily serviced, and maintenance time required is half of that for previous-generation engines, according to Safran. The company offers operators complementary services with the engine, including its electronic engine logbook (Boost) and health monitoring. Bellanger said that more than 1,700 Safran engines across all models are enrolled in Boost.
In October, the Civil Aviation Administration of China (CAAC) certified the WZ16, the Chinese name for Safran’s 1,700- to 2,000-shp Ardiden 3C engine, which was jointly developed and built by Safran Helicopter Engines and Aero Engine Corporation of China (AECC). The engine is installed in the Avic AC352 helicopter, the Chinese variant of the Airbus Helicopters H175 super-medium twin. The AC352 first flew in December 2016 and certification is planned for 2021. Safran and AECC subsequently agreed to strengthen their cooperation on the WZ16. Terms of the deal include study of a potential joint venture in China to support and maintain in-service WZ16s, production launch of the first 120 WZ16s with an opportunity for 100 more engines, and new applications for the WZ16, including a turboprop variant for fixed-wing aircraft.
In November, Safran received EASA type certification for the Ardiden 1U engine, installed in India’s LUH (Light Utility Helicopter). LUH is a new three-tonne, single-engine, multipurpose rotorcraft designed by Hindustan Aeronautics Ltd. (HAL). The aircraft made its first flight in September 2016. The 1,430 shp 1U is an increased-power derivative of the 1,400 shp Ardiden 1H1, an engine that was co-developed by Safran and HAL and is in production with the designation "Shakti." It powers HAL’s Dhruv and Light Combat Helicopter, and more than 250 units are in service. Since its first ground run in 2015, the Ardiden 1U has accumulated approximately 1,000 ground and flight-test hours and has performed well, said Benoit Gadefait, Safran v-p of medium-helicopter engine programs. “Recently, the [LUH] conducted hot and high tests in the Himalayas, showing its abilities to operate in this demanding environment. It took off from remote areas at more than 5,500-meters elevation [18,044 feet] in hot conditions (ISA + 30 degrees C), lifting more than the expected payload.” The 1U also features what Safran calls “an innovative control system specifically designed for single-engine rotorcraft.” The engine additionally incorporates dual-channel Fadec, automatic power check, and APU mode.
Safran received EASA type certification approval for its Aneto-1K engine, as fitted to the Leonardo AW189K, in December, following a flight-test campaign that began in March 2017. The Aneto family produces between 2,500 and 3,000 shp and is intended for super-medium and heavy helicopters. Rated at 2,500 shp, the -1K has a power-to-volume ratio that produces 25 percent more thermal power than existing and similarly rated engines. Safran said this will expand the envelope of missions that helicopters such as the AW189K can perform in applications—including offshore transport, search and rescue, firefighting, law enforcement, and military transport—that demand increased hot-and-high power margins and assured performance in the transitory regime. The -1K’s maintenance regime has been optimized with fewer scheduled tasks and longer service intervals and connectivity features such as health monitoring.
The Aneto has also been selected to power Airbus’s new Racer compound helicopter. The Racer uses elements of the H160’s fuselage mated to a conventional main rotor, a box wing, and twin pusher propellers. Top speed is expected to be in the area of 250 knots.
New programs continuing under development include the Add+ demonstration engine, the technology turboprop demonstrator, and hybrid and electric propulsion for helicopters and eVTOL aircraft.
The Add+ technology demonstrator is based on the current Arrius helicopter engine but with 30 percent of components produced using additive manufacturing. Employing technologies first displayed in June with Add+, several major engine components—including nozzle guide vanes, combustion chamber, and stator rear module—are manufactured using selective laser melting (SLM) techniques. This allows assemblies of hundreds of pieces to be molded into a single piece. By way of example, the accessory gearbox casing is now made of significantly fewer pieces. Add+ also integrates components manufactured by metal injection molding, such as free power turbine blades. Bellanger emphasized that Safran is already incorporating 3D components into production models, including the Arrano and Aneto. But using major 3D content will allow engineers to “think the shape of the engine quite differently,” he said.
Safran and Airbus Helicopters announced over the summer that they are teaming to demonstrate technologies that reduce noise and CO2 emissions for future vertical takeoff and landing (VTOL) aircraft. The two companies signed a letter of intent at the 2019 Paris Air Show to jointly investigate technologies, including electrification, higher-efficiency gas turbines, alternative fuels, and advanced engine architectures that reduce the acoustic footprint of turbines as part of the EU-funded Horizon Europe program.
Ballenger said that the company is continuing its eVTOL “journey” with a focus on developing hybrid propulsion systems featuring a turbogenerator and electric boost motors for helicopters—technology he called “very interesting,” particularly for single-engine helicopters. “Having a backup system like this will make it possible for single-engine helicopters to operate over large cities in Europe. Additional electrical power provides the best efficiency for the cruise phase of flight and provides benefits for fuel savings,” he said.
In September, Safran announced that it was working with ZF Luftfahrttechnik (ZFL) and MT-Propeller, jointly developing a new turboprop engine system aimed at Europe’s unmanned aircraft market. The engine will be optimized for medium and high altitude, up to 45,000 feet, and feature Fadec and propeller control for both power and propeller pitch. It is a derivative of Safran Helicopter Engines’ Ardiden 3-based Tech TP demonstration engine. That engine made its first ground run in June at Safran’s Tarnos, France, facility. The goal of Tech TP, which is part of the European Union’s Clean Sky 2 research and innovation program, is to validate technologies required to develop a new-generation turboprop with lightweight architecture, improved fuel consumption, and lower emissions. Bellanger said the new engine would feature “high levels of design maturity and competitive operating and maintenance costs.”
Bellanger said the eVTOL work involves a “very substantial commitment to the eVTOL, STOL, and logistics markets. Within every company in the Safran Group, there is a huge number of people investing a lot in the technologies.” He stressed that the mission would drive the technologies. “For the logistics market and low-end, on-demand mobility there is a path for a full-electric propulsion system, as there is for the low-payload, last-mile logistics market. Long distances and high payload require a hybrid solution. But we’re still investing a lot in our current thermal engines and believe we can significantly improve fuel savings and efficiencies there. We’re also working on new synthetic fuels. It comes down to a mix of several technologies.”