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This paper deals with the aerodynamic and aerothermodynamic preliminary design activities for the vertical takeoff hopper concept performed in the frame of the Future Launcher Preparatory Programme of the European Space Agency. The reentry scenario with the corresponding loading environment for the proposed vehicle concept is reported and analyzed. The hypersonic aerodynamic and aerothermodynamic characteristics of the vertical takeoff hopper are investigated by means of several engineering analyses and a limited number of computational fluid dynamics simulations in order to assess the accuracy of the simplified design estimations. The results show that the difference between Eulerian computational fluid dynamics and an engineering-based design is smaller than 10% for aerodynamic coefficients, whereas a margin of about 30% has to be taken into account for what concerns the aerothermodynamic results. The final results applicable for the prosecution of the launcher design activity are that, at the condition of peak heating, the vehicle features a nose stagnation point heat flux of about 500 k W/m² and an aerodynamic lift-to-drag ratio of about 1.2. [ABSTRACT FROM AUTHOR]

Current rocket engines, due to their method of construction, the materials used and the extreme loads to which they are subjected, feature a limited number of load cycles.Various technology programmes in Europe are concerned, besides developing reliable and rugged, low cost, throwaway equipment, with preparing for future reusable propulsion technologies. One of the key roles for realizing reusable engine components is the use of modern and innovative materials. One of the key technologies which concern various engine manufacturers worldwide is the development of fibre-reinforced ceramics—ceramic matrix composites. The advantages for the developers are obvious—the low specific weight, the high specific strength over a large temperature range, and their great damage tolerance compared to monolithic ceramics make this material class extremely interesting as a construction material.Over the past years, the Astrium company (formerly DASA) has, together with various partners, worked intensively on developing components for hypersonic engines and liquid rocket propulsion systems. In the year 2000, various hot-firing tests with subscale (scale 1:5) and full-scale nozzle extensions were conducted. In this year, a further decisive milestone was achieved in the sector of small thrusters, and long-term tests served to demonstrate the extraordinary stability of the C/SiC material.Besides developing and testing radiation-cooled nozzle components and small-thruster combustion chambers, Astrium worked on the preliminary development of actively cooled structures for future reusable propulsion systems. In order to get one step nearer to this objective, the development of a new fibre composite was commenced within the framework of a regionally sponsored programme. The objective here is to create multidirectional (3D) textile structures combined with a cost-effective infiltration process. Besides material and process development, the project also encompasses the development of special metal/ceramic and ceramic/ceramic joining techniques as well as studying and verifying non destructive investigation processes for the purpose of testing components. [Copyright &y& Elsevier]