Hybrid propulsion for space applications a critical assessment

The discussion concerning future space launchers and replacement of current propulsion technologies by safer and cleaner high performance systems forms the background for an evaluation of the characteristics of hybrid rocket propulsion, a promising candidate for this application. For the here performed evaluation, determining aspects as performance, reliability, application criteria and costs are considered to assess the potential of hybrid technology for substitution of the main propulsion systems used today: solid and liquid. Although some decisive advantages of hybrid systems can be identified, the state-of- the-art does not allow a final decision on their availability. Despite claims that hybrids could be made operational in near future, it seems that there is a considerable way to go until a system comparable to nowadays used propulsion concepts is available.