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Abstract: This paper describes the final design status of a partially reusable space transportation system which has been under study for five years within the German future launcher technology research program ASTRA. It consists of dual booster stages, which are attached to an advanced expendable core. The design of the reference liquid fly-back boosters (LFBB) is focused on LOX/LH2 propellant and a future advanced gas-generator cycle rocket motor. The preliminary design study was performed in close cooperation between DLR and the German space industry. The paper''s first part describes recent progress in the design of this reusable booster stage. The second part of the paper assesses a long-term, strategic scenario of the reusable stage''s operation. The general idea is the gradual evolution of the above mentioned basic fly-back booster vehicle into three space transportation systems performing different tasks: Reusable First Stage for a small launcher application, successive development to a fully reusable TSTO, and booster for a super-heavy-lift rocket to support an ambitious space flight program like manned Mars missions. The assessment addresses questions of technical sanity, preliminary sizing and performance issues and, where applicable, examines alternative options. [Copyright &y& Elsevier]

Abstract: Eurockot is the German–Russian joint venture company providing low earth orbit (LEO) launch services with the Russian ROCKOT launch vehicle. ROCKOT is a 3 stage liquid fuelled launch vehicle, which can place payloads of up to 1950kg into LEO and has the capability to serve sun-synchronous, near polar and highly inclined orbits from its launch site at Plesetsk Cosmodrome in northern Russia. The purpose of the paper is to describe the suitability of ROCKOT specifically for LEO earth observation and scientific missions. The paper provides an overview of Eurockot''s recent commercial launch experience and future customers. In particular, it describes in some detail the recent launch campaigns and missions undertaken to satisfy the particular customer needs. After successful launches of GRACE and IRIDIUM satellites in 2002, five further contracts have been concluded on the ROCKOT launch vehicle, three of which are for launches of earth observation systems. [Copyright &y& Elsevier]

Abstract: Nuclear Electric Propulsion (NEP) is a technology conceptually proposed since the 1940s by E. Stuhlinger in Germany. The JIMO mission originally planned by NASA in the early 2000s produced at least two designs of ion thrusters fed by a 20–30kW nuclear powerplant. When compared to conventional (chemical) propulsion, the major advantage of NEP in the JIMO context was recognized to be the much higher I sp (lab-tested at up to 15,000s) and the capability for sustained power generation, up to 8–10 years when derated to I sp about 8000s. The goal of this paper is to show that current or near term NEP technology enables missions far beyond our immediate interplanetary backyard. In fact, by extending the semi-analytical approach used by Stuhlinger, with reasonable ratios α≡power/mass of the propulsion system (i.e., 0.1– 0.4kW/kg), missions to the Kuiper Belt (40AU and beyond) and even the so-called FOCAL mission (at 540AU) become feasible with an attractive payload fraction and in times of order 10–15 years. Further results regarding missions to Sedna’s perihelion/aphelion, and to Oort’s cloud will also be presented, showing the constraints affecting their feasibility and mass budget. [Copyright &y& Elsevier]

Abstract: This paper presents some of the results of an 18-month study into robotic on-orbit servicing (OOS) by the authors for the German Aerospace Center (Deutsches Zentrum fur Luft und Raumfahrt (DLR)), which leads the world in this area of space technology development. Rather than dealing with technology issues, however, we deal with issues concerning the potential market (the “demand” side) for OOS. We present the case that robotic OOS is not only commercially feasible, but also even more strongly assert that it is essential. We consider in particular the recent high incidence of on-orbit failures in geostationary telecommunications platforms. We present the sobering statistics of such failures, and determine that only OOS can mitigate these and future failures. OOS represents the first space-based commercial opportunity that serves the space industry itself rather than Earth-oriented applications more typical of commercial space activities, and to that end provides the basis for future space infrastructure development. [Copyright &y& Elsevier]

Abstract: This paper traces the development of rocket technology in Germany from the 1930s and 1940s that led to the massive, and historically unprecedented, transfer of rocket, missile, launch-vehicle and related technologies to the post-World-War-II United States. This achievement was made possible by an initial group of 118 German rocket specialists to which others were gradually added. The contributions to rocketry, upper atmosphere and space research, and eventually manned space travel provided by Germany''s Wernher von Braun and his team of engineers, scientists, technicians and support personnel is, in particular, described, and the ongoing influence of the innovations they introduced is considered. [Copyright &y& Elsevier]

In late 1946, the Australian government formalised its attempts to acquire post-war German scientific and technical expertise with the establishment of the Employment of Scientific and Technical Enemy Aliens (ESTEA) scheme. Under this scheme, between 1946 and 1954 some 150 scientists, engineers and technicians were recruited to work in Australia, although several thousand candidates were actually under consideration.Among those who sought employment in Australia under this program was Austrian-born rocket pioneer Eugen Sänger, his long-time colleague and future wife Irene Bredt and several others who had been, to a greater or lesser extent, involved in wartime rocket development in Germany. With the establishment of the Anglo-Australian Joint Project for long-range missile development in 1946 and the opening of the Woomera Rocket Range in 1947, the prospect of enhancing the expertise-base within the Long Range Weapons Establishment by the acquisition of a team of experienced German researchers should have been appealing to the Australian Government: yet the 1949 applications by Sänger and the others were eventually rejected in 1951.This paper will outline the story of the now-forgotten attempts by Sänger and other personnel associated with the German rocket program to migrate to Australia under the ESTEA scheme. It will look at the background and operation of the ESTEA program and consider in detail the case of Sanger et al., examining both the reasons that may have prompted them to apply for work in Australia in the first instance and the possible reasons their ultimate rejection. [Copyright &y& Elsevier]

The Hopper, a concept for a reusable launch system was developed and found attractive in the frame of FESTIP, ESA''s Furure European Space Transportation Initiation Programme Later, in the national German ASTRA programme this concept was adapted to newly emerged requirement and subjected to a detailed design loop. Taking off horizontally and staging at high sub-orbital velocity, the Hopper needs a rail-guided launch sled, downrange landing, re-transportation back to the launch site, and one, but only one upper stage. Horizontal take-off is used to improve safety and to reduce thrust requirement, and number, mass, and cost of main engines, and also problems with vehicle centering. Transportang of the cargo (e.g.) payload and expendable upper stage) in the RLV results in only one aerodynamically affected flight configuration. Staging at high sub-orbital velocity above the sensible atmosphere enables the use of only one standardised upper stage for all missions. Using a cryogenic upper stage the Hopper system is nearly optimally staged for the dimensioning GTO mission. The paper describes the consolidated unmaanned RLV concept and highlights areas of special interest, evolution potential, and further steps. [Copyright &y& Elsevier]