The European research project Hybrid Electric Regional Aircraft Distribution Technologies (HECATE), funded by the European Clean Aviation partnership and led atUNISA by prof. Marco Sorrentino - DIIn, aims to deliver transformative technologies to electrical distribution for future Hybrid Electric Aircraft. The HECATE project focuses on developing transformative electrical distribution technologies for hybrid-electric aircraft to support the aviation industry's shift toward electric propulsion. Building on the success of more-electric aircraft (MEA) technologies, which reduce weight, fuel consumption, and operating costs, HECATE aims to address the need for high-power, high-voltage systems that can enable hybrid-electric propulsion for larger aircraft. The project seeks to contribute to achieving a 30% reduction in net emissions by 2035 and zero emissions by 2050. The research consortium includes several leading European universities (e.g., Carlos III, Aalborg, Nottingham,UNISA) and aviation companies (e.g., Leonardo, Airbus).UNISA main contributions are devoted to the model of fuel cell systems and their integration to the battery. The role of the members joining DIEM (prof. Addesso and prof. Postiglione) is related to the reliability evaluation of the solutions proposed within the project.