The EFACA project consists of 6 main objectives at 3 levels. Level 1 consists of three TRL3 demonstrations of technologies relevant to the greening of aviation: (WP1) bench testing of a gearbox combining input from gas turbine and electric motor for an hybrid turbo-electric propulsion system for a propeller-driven regional aircraft; (WP2) comparative testing of fuel cells with conventional liquid and novel phase cooling, to show the benefits up to 20% of the latter in higher net power, reduced heat losses, and smaller volume and weight also reengineering of fuel cell and structural components to increase power-to-weight ratio up to 80%; (WP3) static ground testing of a complete liquid hydrogen fuel system from cryogenic tank to vaporization and combustion in a wide range of operating regimes and simulation of application to the speed and altitude flight envelope of jet airliners. Level 2 consists of two preliminary designs: (WP7) an 80-seat 1000-km range regional propeller driven aircraft including design and integration of hybrid turbo-electric propulsion; (WP89) a 150-seat 2000-km range jet liner with liquid hydrogen fuel including design and integration of cryogenic tanks and fuel system. At level 3 a road map (WP10) for the achievement of the EU environmental targets for aviation synthetizing conclusions in four steps: (i) current status on (WP4) emissions and (WP5) noise versus future targets and gap to be covered; (ii) assessment of relevant technologies to cover the gaps, including (WP6) battery electric and (WP9) sustainable aviation fuels, besides hydrogen (WP7) fuel cells and (WP8) turbines; (iii) most suitable technology for each class of aircraft (light, small and medium regional, single and twin aisle jetliners), and maturation time of the technology; (iv) contribution of each aircraft class to CO2 and non- CO2 global and local emissions and noise, leading to (WP10) a comprehensive road map of actions for carbon-free or emissions-free flight.

HERA will identify and trade-off the concept of a regional aircraft, its key architectures, develop required aircraft-level technologies and integrate the required enablers in order to meet the -50% technology-based GHG emission set in SRIA for a Hybrid-Electric Regional Aircraft. The HERA aircraft, having a size of approximately of 50-100 seats, will operate in the regional and short-range air mobility by mid-2030 on typical distances of less than 500 km (inter-urban regional connections). The aircraft will be ready for future inter-modal and multi-modal mobility frameworks for sustainability. The HERA aircraft will include hybrid-electric propulsion based on batteries or fuel cells as energy sources supported by SAF or hydrogen burning for the thermal source, to reach up to 90% lower emissions while being fully compliant with ICAO noise rules. The HERA aircraft will be ready for entry into service by mid-2030, pursuing to the new certification rules, able to interact with new ground infrastructure, supporting new energy sources. This will make HERA aircraft ready for actual revenue service offering to operators and passengers sustainable, safe and fast connectivity mean at low GHG emissions HERA will quantitatively trade innovative aircraft architectures and configurations required to integrate several disruptive enabling technologies including high voltage MW scale electrical distribution, thermal management, new wing and fuselage as well as the new hybrid-electric propulsion and related new energy storage at low GHG. To support this unprecedented integration challenge, HERA will develop suitable processes, tools and simulation models supporting the new interactions, workshare in the value chain and interfaces among systems and components. HERA will also elaborate on the future demonstration strategy of a hybrid–electric regional aircraft in Phase 2 of Clean Aviation to support the high TRL demonstration required for an early impact for HERA solutions.

The AREANA project addresses the call for "Aviation research synergies between Horizon Europe, AZEA and National programs" by providing advanced novel approaches to foster the European aviation research ecosystem. It encompasses three interconnected, yet thematically distinct parts. Firstly, approaches improving on the coordination of aviation funding programs will be addressed by coordinating and supporting synergies between European, National, and Regional R&I aviation programs. The project aims to facilitate joint calls or other co-funding mechanisms that align EU, National, and Regional activities in specific fields and accelerate the update and sharing of aviation technology infrastructures in the European Research Area. Secondly, the upcoming Aerodays will be prepared. The consortium suggests them to take place during the first half of 2025 in Warsaw, Poland. They would then coincide with the Polish presidency of the Council of the European Union. Thirdly, AZEA (Alliance for Zero Emission Aviation) activities will be supported by conducting mappings and analysis, including the identification of potential technological and administrative gaps and lack of related R&I and standardization efforts, removing the obstacles for zero-emission aviation. Close cooperation with the Advisory Council for Aviation Research and Innovation in Europe (ACARE) and other institutions is expected. The AREANA project will help to sustain and foster the European aviation research ecosystem, thus helping to achieve the environmental goals while ensuring European competitiveness. This will be achieved by connecting and aligning different funding mechanisms, bringing together aviation stakeholders during the Aerodays and supporting the Alliance for Zero Emission Aviation.

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.

The objective of EXAELIA is to investigate and to answer the needs for novel flying testbeds for de-risking the development of disruptive future long-range aircraft, accelerating the reduction of all aviation emissions and its climate and environmental impacts in 2050. EXAELIA investigates, through advanced multi-disciplinary digital methods, the potential emissions reductions of long-range air traffic offered by promising blended wing body aircraft configurations and by hydrogen-powered tube-and-wing configurations, including their constituting radical new technologies. Critical uncertainties are identified, in particular those requiring flight validation for de-risking the future aircraft development. For those flight test requirements which go beyond the capabilities of existing assets, novel flying testbeds are developed towards their preliminary design and demonstrated to answer the flight validation needs, efficiently combining these needs in potentially costly large-scale modular flying testbeds. Roadmaps are prepared for the further development of the EXAELIA flying testbeds and their use in the development of the future long-range aircraft, entering into service before 2050 with a maximum contribution to reducing aviation impact and emissions (~49% of air transport system emissions in 2019 came from long range aircraft). Operational and business plans for these indispensable test bed assets are provided as well. The EXAELIA consortium consists of the major European research centres and academia in future aircraft conceptual design and analysis, flight testing, and flying testbed development, and 4 SMEs, all with a strong record in collaboration. An Advisory Board, including European aircraft and engine manufacturers and further industries will provide guidance to achieving the objective and to obtaining their support to the roadmaps. The total grant request of this 42-month action is 16 233 889 Euros.