Roadmap Towards a Greener Kick-Stage Propulsion System

The fast-paced growth of the space sector brings in new challenges especially with upcoming complex missions combining multi-orbit deliveries and/or on-orbit servicing such as Active Debris Removal (ADR). Europe has taken up the challenges and is working on extending its launchers portfolio and capabilities. In this framework, a new add on, the kick stage, confers strategic advantages to the launcher in expanding its missions’ range. While many kick stages are currently developed, or already in use worldwide, this paper pays a particular attention to the new ASTRIS kick stage developed and optimized for A6 and its next kick stage generation already under conceptual study, LunaNova, at ArianeGroup Bremen for A6 Evolution. The project takes place under the ESA Future Launchers Preparatory Programme (FLPP) and is already implementing new technologies, namely innovative pressurization system and green propellants which are of special interest here. The paper starts by introducing the kick stage capabilities, especially the LunaNova ones, to then focus on the cost-oriented trade-off performed to select the fuel to use in combination with 98%-HTP to power the LunaNova vehicle. The paper then concludes by discussing the system impacts of implementing green propellants within the operational kick stage life cycle and its possible enhancement (namely the implementation of an e-pump).