The following features are part of the scope:

• overall propulsion system architecture, capable of demonstrating all the requested performance targets.
• All major modules in the powerplant system, including:
  • Low speed fan system, next generation composite architecture and installation concept including nacelles where required for lowest weight, drag and noise.
  • New generation power gearbox for SMR scale featuring a low weight and volume design and reduced loss turbomachinery transmission with optimised oil system, delivering new standards of transfer efficiency, and facilitating highest propulsive efficiency.
  • High efficiency core with advanced light-weight materials, cooling system and aerodynamics that enables higher level of power offtake than current operations and reliable operations of the product in all environments and throughout the whole flight envelope with adequate margins.
  • Advanced low NOX combustion system designed to deliver beyond state-of-the-art reductions in NOx and nvPM across the flight cycle (e.g., LTO, cruise). The system being designed to eliminate architecture and scaling challenges such as coking and thermoacoustic instabilities.
  • Next generation High-Speed Low-Pressure Turbine, achieved by new standards of blade aero-loading that enable high efficiency and low-weight, integrating novel technologies to minimise the design constraints of aerofoil aeroelastic phenomena.
• Variable cycle technology that allows the engine to adapt and provide power more efficiently depending on operation.
• Engine integrated electrical motor generators enabling more-electric operations (e-start, eactuation etc.)
• Smart Offtakes that integrate with aircraft systems to enable optimised power management throughout the flight cycle unlocking design synergies to deliver optimal physical and functional sizing.
• High efficiency Fuel and thermal systems that enable the use and benefits of drop-in 100% SAF usage, and further developed for non drop in SAF system benefits e.g. due to higher calorific value, thus improving thermal efficiency.
• Optimised engine-aircraft integration considering aerodynamic, structural and systems improvements to reduce weight and increase efficiency.

The second objective of the topic is to prepare the fully instrumented and modified Flight Demonstration Platform to enable the flight test of the Ultra-High Bypass Ratio ducted turbofan architecture for SMR aircraft, at a later stage in the programme, to validate the technologies at TRL5 including:

• Development and acquisition of the relevant flight instrumentation, fulfilling the performance targets for flight test instrumentation systems detailed in the section on performance targets, to carry out in-flight measurement of thrust, emissions, and other characteristics such as noise and soot, as applicable. The technologies developed should reach the maturity of TRL6 during the Clean Aviation programme duration and fulfil the need for in situ measurements and access hard-to-reach areas.
• Engine integration activities on the flight test demonstrator should be performed up to Critical Design Review phase and include a full aircraft performance analysis to support flight clearance and flight test campaign, aircraft systems and airframe adaptation including hardware and software.
• The need for Wind Tunnel Testing activities supporting flight clearance shall be assessed.

The requirements and integration constraints of the propulsion system should be established in close cooperation with the SMR aircraft concept integration and impact assessment project64, such that the assumptions relative to the aircraft operating envelope, to the flight mission profile, to the aircraft range, to the aircraft cruise speed, to the aircraft seating capacities and to the main aircraft sizing parameters in general, should be fully consistent with those applicable in the abovementioned Clean Aviation project focusing on SMR aircraft concept integration and impact assessment. All data required to characterize emissions (including non-CO2 effects, such as NOx, water vapour and nonvolatile Particulate Matter, and noise) shall be modelled and measured as required to feed aircraft level impact assessment.

The project is required to exploit the involvement and expertise of EASA in the proposal to de-risk and secure the certification of novel propulsion technologies with the aim to assess and define how the envisaged solutions will have the potential for certification.

With the aim to define the route to exploitation, operational assessment should be done to support the successful deployment and continuous operation of future SMR aircraft, including ground operations, repairability and maintainability.

Performance Targets: A set of top-level goals will be the basis for performance targets, in particular:

• No less than a 20% reduction in CO2 emissions at aircraft level vs 2020 SoA, after overall propulsion system integration, not considering any aerodynamic and weight savings from other components.
• Engine/installed performance compliant with the aircraft performance target of 30% emissions reduction (possibly expressed in terms of overall emissions per passenger kilometre).
• Evaluation, monitoring and reporting of key parameters needed to assess non-CO2 effects (including NOx, water vapour and non-volatile Particulate Matter emissions), to ensure compliance with foreseen regulations and standards for a 2035 EIS.
• Noise emissions levels fully compliant with current applicable ICAO noise standard (chapter 14 noise limits), with adequate certification cumulative noise level margin, while considering foreseen updates to the noise standard in view of a 2035 EIS.
• Targets must be compatible with safety as an overarching requirement and consistent with the certification path, including the CRL 5 objective (refer to the Description of the call topic and topic specific conditions).
• The propulsive system and components will have to comply with requirements issued by the aircraft integrator at the start of the project (volume, weight, drag, performances, interfaces) and provisions will be included to mitigate risks associated to such requirements.
• Flight Test Instrumentation systems should demonstrate equal or higher precision than current state of the art references, data reliability and robustness in operating conditions, in compliance with industry standards such as DO-160 and DO-178.