Following results from the MALET CfP, it underlines the major challenges of modelling Environmental Control System (ECS) and thermal management architectures. A first topic is related to modelling the ECS for covering the full usage envelop, including starting and on/off phases that constitute themselves a real challenge. More specifically, the heat exchanger performances modelling in presence of moist air and refrigerant is one of the major issue for ECS modelling. A second topic is related to the capability to accurately compute electrical losses for system application without compromising the overall computational cost. From detailed developed models in the project, the usage of data analytics technologies should enable to achieve the digital twin with expected accuracy and computational costs. Please refer to the full topic descriptions document published in this call.