A technology shift towards more electric solutions is emerging in aerospace actuation. New technology brings new challenges, especially for the preliminary design process of actuation systems and components that cannot simply be a duplicate of former practices. In this way, it is no longer meaningful to proceed to sizing by points (as for hydraulic actuators). Instead, it is necessary to take into account mission profiles covering all possible sizing drivers (e.g. maximum speed and torque, fatigue, thermal behaviour, vibrations, and shocks) and addressing various design criteria (e.g. geometrical envelope, weight and reliability). For this purpose, appropriate top level evaluation tools should be developed to support an efficient preliminary design. In this article, such tools have been proposed in the form of models for the major generic EMA components, which are first identified by a state-of-the-art of the actuation systems in aerospace and aeronautics. This state-of-the-art also highlights the different stages or design points of view encountered in early preliminary studies. Then, a classification of the design parameters associated with these stages has been proposed to fit into a model-based design approach. Obtaining these parameters quickly and easily is a critical issue for sizing calculations and early simulations in the framework of risk mitigation. The scaling law approach presented in this article responds to this issue by allowing the development of component models from a limited number of input parameters. Moreover, the scaling laws developed are representative of the state-of-the-art of technology and require a single component reference instead of a large amount of data that are cumbersome to set-up and maintain. These laws have been compared with manufacturers' catalogue data to validate their relevance. Finally, the usefulness of these estimation models has been illustrated with potential applications for EMA model-based designs.