Future space systems require innovative computing system architectures, on account of their size, weight, power consumption, cost, safety and maintainability requisites. The AIR (ARINC 653 in Space Real-Time Operating System) architecture answers the interest of the space industry, especially the European Space Agency, in transitioning to the flexible and safe approach of having onboard functions of different criticalities share hardware resources, while being functionally separated in logical containers (partitions). Partitions are separated in the time and space domains. In this paper we present the evolution of the AIR architecture, from its initial ideas to the current state of the art. We describe the research we are currently performing on AIR, which aims to obtain an industrial-grade product for future space systems, and lay the foundations for further work.