• Dietrich Koelle

It is generally assumed that substantial improvements of technology are required for the next generation of (reusable) launch vehicles. However, this is not necessarily true, even though technology development programs have been performed or started in Europe (Sänger, FESTIP, FLTP, Astra), the USA (NASP-, X-33-, X-34-, SLI-Programs) and Japan. The new technologies required depend very much on the launch VEHICLE CONCEPT envisioned. Therefore, an early assessment and selection of an RLV System is required. There are simple and cost-effective reusable launch systems which can be built with presently existing technology (such as the Kistler K-1 which is under development); and there are highly complex winged RLV concepts with combined propulsion requiring a host of new technologies. In this case it is even questionable whether such systems will be cost-efficient at all. The tremendous difference of potential launch vehicle system concepts and the required new technologies do not only have a dramatic effect on development cost and time schedule but also on the later operability (risk and reliability) as well as on the finally achievable reduction of transportation cost into space.