To reduce their climate impact, the future LR aircraft configurations explored in EXALIA rely on new energy sources identified as SAF and H₂. However, the typical LR mission requirement to carry more than 300 passengers beyond 9000 km poses several design challenges to the aircraft. First, the high speed requires particular attention to aerodynamic design to achieve the highest possible lift-to-drag ratio. Then, the necessity to carry a large volume of fuel over long distances automatically implies internal space constraints and an optimized light structure. Last, the size of these airplanes necessitates large and heavy propulsion systems.
Taking into account these constraints and the results of previous studies, the EXAELIA project focuses on the maturation of Blended Wing Body concepts and a Tube And Wing concept. To provide an additional and significant improvement in energy consumption, these future LR aircraft also integrate novel promising propulsion systems. To limit the design space, EXAELIA concentrates on following the most promising configuration/propulsion combinations:
- SAF-powered BWB & 2050 technology UHBR, with a derivative using a Distributed Electric Propulsion (SAF turbogenerator and superconductivity);
- H₂-powered BWB & Geared, Intercooled, Free Opposed Piston (FOP).
- H₂-powered TAW & Free Double Piston (FDP) Composite Cycle Engine (CCE), with a derivative using an Intercooled Recuperated Turbofan;
During the project, 2 distinct aircraft design loops take place with increasing model refinement and the addition of disciplinary/systems assessment to ensure a higher maturity of the designs. This approach allows a parallel development of innovative technologies that will be later on integrated in the sizing and synthesis loop II.
At project level, it is key to measure the benefits of the future concepts in terms of energy consumption. Thus, Architects in charge of the configuration will model with their own toolset the reference aircraft and the baseline Aircraft (possible future LR aircraft with 2050 evolutionary technology). In this manner, benefits and drawbacks of the various technologies, configuration and propulsion systems will be identified.
The LR Aircraft design is concluded by a specific task dedicated to the identification of critical technologies that are mandatory to meet emission targets and where maturation can be accelerated by specific flight tests with a flying testbed. The work relies mainly on sensitivity assessment to point out the critical aspects.