Reducing SMR aircraft environmental impact is a priority of the Clean Aviation SRIA, which objective is to have technologies ready for the future generation of SMR aircraft. The engine is key in this effort and the Open Fan engine architecture is the most promising solution in terms of fuel efficiency to both achieve environmental goals (20% emissions reduction versus 2020) and target a rapid Entry into Service, as early as 2035. In synergy with national programs, OFELIA will gather a large European consortium to contribute to the RISE technology demonstration announced in June 2021. OFELIA aims to demonstrate at TRL5 the RISE Open Fan architecture, for the SMR to achieve or surpass the Air Transport Action Group’s goals on the way towards Carbon neutrality by 2050. To this end, OFELIA will focus on this high TRL full scale demonstration of the engine architecture and on the development of key enablers for the Open Fan. OFELIA will allow installation of an increased fan diameter on a conventional aircraft configuration, thanks to innovative turbomachinery technical solutions. Following the architecture definition, OFELIA will perform a large-scale Open Fan engine ground test campaign, deliver flightworthy propulsive system definition and prepare an in-flight demonstration for the phase 2 of Clean Aviation. The project will also optimize the engine installation with the airframer and address certification, in close collaboration with airworthiness authorities, taking advantage of the permit-to-fly activity. OFELIA will then deliver a TRL5 Open Fan engine architecture for SMR, demonstrate a credible path to 20% CO2 reduction versus 2020 and prepare the path to flight tests to consolidate the roadmap for EIS2035. As part of the technology maturation plan, the compatibility of Open Fan to hydrogen will be investigated in coordination with H2 pillar.

Air travel is an important supplement to other means of regional transportation and in some regions the only viable solution. However, the regional transport market is highly competitive, and air travel must demonstrate that it can compete with hi-speed trains, cars or coaches. One major issue is the perception of the high CO2 and greenhouse gas (GHG) emissions by planes for these short journeys. Hybridization of the propulsion system enables combining the technical components benefits, thereby achieving an overall efficiency improvement. It is a concept well understood by the general public, due to the hybridization of automobiles, and can bring a real impact on the reduction of GHG emissions. While enabling rather than limiting new sources of energy in aviation, an ambitious path to reduction of greenhouse gases and the pathway to a cleaner and greener aviation for regional flights is built upon three pillars: • Electric hybridization • An ultra-efficient turboprop thermal engine • 100% SAF compatibility HE-ART will be a first step on the path to hybridization of regional aircraft and a reduction of up to XX% of GHG. This will be accomplished by achieving a strategic global objective of demonstrating, within 36 months, the viability of a hybrid electric thermal turboprop (e-TP) within the scope of a dedicated integrated ground test demonstrator. HE-ART will build on existing state of the art integrating the following technologies into the demonstrator: • Core thermal engine • Electric motor and power electronics • Gearbox • Propeller • Nacelle and heat exchanger This will be executed in conjunction with the Top-Level Aircraft Requirements that will be defined in parallel Clean Aviation research projects. To ensure that these requirements are met in full, HE-ART brings together the leading engine manufacturers, Rolls Royce and Safran with leading airframers, ATR, Airbus and Leonardo along with key manufacturers and research organisations.