1. The question of future launch vehicles, those which will begin operation after 2020 and can anticipate operation extending to the second part of the century is a major issue for the future of space transportation players. In previous RLV system studies performed over the last ten years, potential system concepts and technology requirement needs have been identified. The studies performed up to now allowed to sweep a certain number of possible RLV configurations and investigate their advantages and disadvantages : • Semi-reusable concepts with a reusable first