Callisto demonstrator: Focus on system aspects

Japan and Europe are currently developing their new competitive launchers that are planned to enter into operation very soon, and they are based on expendable concepts. In the same time, reusable concepts are successfully operated in USA. Reusability could be the solution for further improvement of competitiveness of future launch system. Then, one of the main question we have to address is “do we master the technics and technologies necessary to recover and to reuse part of launchers?". This is why, in order to assess the technical difficulties and potential benefits of reusability, CNES, DLR and JAXA have decided to joint their competences and their efforts in the development of a scaled reusable VTVL in-fight demonstrator dubbed CALLISTO (Cooperative Action Leading to Launcher Innovation in Stage Toss - back Operations), allowing to recover and reuse the vehicle under conditions representative for an operational launcher. CALLISTO vehicle is about 13 m high and 1.1 m diameter, propelled by a JAXA LOX/LH2 engine able to reignite in flight and with throttling capability. It will be operated from the French Guiana Space Centre and sized for about 10 flights following different mission profiles, opening the flight domain from low altitude test up to a full demonstration profile. CALLISTO will be launched from the DIAMANT site and will land on the same site. This paper will provide an overview of the project and its missions after the System Preliminary Definition Review,. This paper will address: 1) Architecture design activities focusing on: Trajectories satisfying demonstration objectives as well as operational constraints, the definition of the flight domain due to multiple mission profile, flying qualities during descent phase, including aero-shape design, flight control and management of different actuators, 2) CONOPS focusing on safety critical operations before lift-off and after landing, and associated means 3) Maintenance, Repair and Operations guidelines 4) Different products and module definition and in particular the management of COTS 5) Ground segment definition.