EXACT Sustainable Aircraft Concepts Results and Comparison

The project "Exploration of Electric Aircraft Concepts and Technologies" (EXACT) serves as a central integration initiative of DLR with the primary objective of exploring how the climate impact of aviation can be drastically reduced while maintaining economic competitiveness. The focus of the project was set on intra-continental transport, resulting in the development and assessment of various sustainable aircraft concepts for two distinct aircraft classes—a 70-seater regional class and a 250-seater short-range class. The paper describes the unified framework developed for the project, which enabled the consistent modelling and comparison of aircraft concepts with various propulsion system types, including synthetic-kerosene-driven, hydrogen-based, fuel-cell-powered, and plug-in hybrid-electric configurations. The employed methodological approach incorporates component models for structural load analysis, mass estimation, energy storage systems, aerodynamics, and mission performance. The models comply with the consistent integration of radically different technologies at the aircraft level and encompass interfaces for feeding global-fleet-assessment methods under identical boundary conditions. The paper also outlines the project results, which provide valuable insights into the trade-offs, synergies, and relative performance of the different technologies, while demonstrating the advanced modelling capabilities required to evaluate future sustainable aviation solutions.