PARIS, FRANCE — The French engine manufacturer Safran has provided information on the primary technologies it plans to develop as part of the EU-funded OFELIA (open-fan for environmental low impact of aviation) project, which is aimed at supporting work on the RISE open-fan demonstrator being conducted by CFM International, a joint venture between Safran and GE Aerospace. 

In September of the previous year, the Safran-led OFELIA project was one of 20 chosen by the EU's Clean Aviation body in its initial funding round.

Clean Aviation will provide OFELIA with €100 million ($110 million) for the three-year project, which commenced in January and is set to run until December 2025. Although Safran has not disclosed the amount of funding the 27-company consortium is contributing to OFELIA, Clean Aviation mandates that industry contributions to a project must be at least 1.5 times the size of the EU grant.

OFELIA's objective is to showcase the advantages of an open-fan architecture for a new narrowbody engine, slated to enter service in 2035, with a critical aim of achieving a 20% fuel-burn saving compared to current powerplants. In June 2021, CFM introduced the RISE demonstrator program, which shares the same fuel-burn reduction goals, with flight-tests planned to start by the middle of the decade.

Drawing from research on open-rotor architectures conducted through the EU's Clean Sky programs, which preceded Clean Aviation, Safran and its OFELIA partners plan to advance the necessary systems for a new narrowbody engine to technology readiness level 5 by the end of the project. Safran will collaborate with GE-owned Avio Aero and GKN Aerospace to design and produce components for the demonstrator engine.

The OFELIA consortium will investigate topics such as whirl flutter, unducted fans – consisting of a single-stage propeller and a row of static vanes – high-speed boosters, and high-speed low-pressure turbine aerodynamics. Additional development work will concentrate on a high-power compact reduction gearbox, lightweight engine components, combustor emissions, high-pressure compressor aerodynamics, and hybrid-electric technology. CFM has previously detailed the incorporation of an electric motor-generator in the proposed RISE architecture.

Only ground testing is scheduled for the first phase of Clean Aviation. While flight testing is anticipated in the program's second stage, starting in 2026, there is no certainty that Safran will obtain funding for such activities, particularly as there are two competing engine designs in the same development stream. CFM has an independent agreement with Airbus, announced in July 2022, to demonstrate the RISE engine on an A380 flying testbed in the latter half of the decade.

To prepare for Clean Aviation's second phase, Airbus will "prepare the preliminary dossier" to support A380 flight tests, according to Safran. The open-fan engine will also be capable of running on sustainable aviation fuel or hydrogen. Safran will partner with Airbus to iteratively develop the data supporting such operations for both the aircraft and engine.

OFELIA consortium members consist of Safran's nacelle, transmission, and booster businesses, GKN Aerospace, Avio Aero, GE's German division, aerospace research institutes Cenaero, DLR, NLR, ONERA, and VZLU, and universities in Dresden, Graz, and Turin.