Design, Manufacturing and Assembly of the STORT Hypersonic Flight Experiment Thermal Protection System

Abstract

STORT is a DLR project focused on testing of key technologies for flight at hypersonic Mach numbers of higher than 8 for a relatively long time. The overarching aim of the project is to support cost reduction of future space transportation systems while at the same time keeping them highly reliable. To this end, reusability of all stages of future launcher systems is a prerequisite. For first stages, a Mach number of 8-10 seems to be the optimum staging velocity, which means that technologies for the return flight of first stages at those speeds need to be developed and validated. Consequently, STORT aimed at achieving operating conditions representative of such high-energetic reentry flights for reusable first stages at Mach 8, to support the optimization and validation of technologies and simulation tools for the development of future space transportation systems. The present paper thus describes the design, manufacturing and integration of the rocket forebody assembly up to the launch of the vehicle. In addition, an overview of the collected flight data from the thermal protection system sensors is given. The forebody thermal protection system requires the use of ceramic matrix composite material for protection from the high heat loads experienced during the flight. In the present case the thermal protection system was constituted by C/C-SiC composite structures built in-house by DLR. The main elements were a conical nose element and four thin-walled shell segments manufactured via filament winding of carbon fibers. Via an in-situ joining process, integral fixation brackets from CMC material were permanently attached to the shells. The underlying forebody main structure to which the thermal protection system structures were connected was made from aluminum.