I was 7 years old when I watched diffused pictures of Aldrin and Armstrong on the moon, and ever since the Apollo program, my dream has been to participate in space exploration. After school, I studied electronics and aerospace science at German universities. In 1991, I began to work as a scientist at the German Aerospace Centre (DLR). The first task was the design of a fuselage concept for the German "Sänger" project, which was a concept for a two-stage-to-orbit transport system. The next step was the design of an advanced ceramic-based thermal protection system (TPS) for this vehicle. After cancellation of the Sänger program, my task was to build up high-temperature test facilities for TPS and hot structures needed for the European "Hermes" space taxi. In parallel, further TPS concepts for reusable space vehicles were designed.
Today, I am the project manager for the TPS nose development of the Crew Return Vehicle (CRV) for the International Space Station. The CRV is designed to offer a safe return to Earth in case of emergency evacuation for up to seven astronauts on board the space station. It is planned to launch the CRV within the cargo bay of the space shuttle and dock it to the station where it will stay for up to 2 years. In case of an emergency, the astronauts will move into the CRV and release it from the station. After ignition of the de-orbit module, the CRV will reenter Earth's atmosphere and will automatically be guided to a suitable landing site. The final approach will be performed via a controlled large parafoil. The shape of the CRV is taken from the X-24 lifting body, which flew in the early 1970s during development of the space shuttle.
The design lead for the CRV is at NASA. However, a significant share of the vehicle's structure and avionics will be delivered by European companies. One part of this is the TPS nose cap, which is under development at DLR. Located at the tip of the vehicle, the nose cap has to withstand very high thermal and mechanical loads. The surface temperature during reentry is estimated up to 1750°C for 15 minutes. This is much higher compared to what the space shuttle experiences, which does not exceed 1500°C. The challenge during design was to handle the thermal expansion of the nose shell and to insulate the aluminium substructure against the high surface temperature within a very small distance of 50 mm.
Nose of Crew Return Vehicle X-38.
One flight hardware set of the nose cap system has already been delivered to NASA and will be mounted on the X-38, which is a prototype of the CRV. X-38 is nearly finished and is planned to have its unmanned maiden flight including a real reentry in 2003. The development of the X-38 hardware took approximately 4 years from the first concept drawings until delivery of the hardware. During this time, it was necessary to deal with aerothermodynamics, new materials like fibre-reinforced ceramics and high-temperature resistant metals, static and dynamic structure analysis, thermal analysis, quality assurance, and management. It was exciting to have a close cooperation with different national and international companies and agencies.
Aerospace is a rather young science for engineers and scientists. The first powered aircraft flew only 100 years ago, and the first modern rocket had its lift-off only 60 years ago. Both types of vehicles allowed humankind to enter a new sphere. At present, the fascination of technology and the possibility of leaving Earth is alive. Air transport is a fast-growing market and brings people together. The world becomes smaller. Flying into space opens a new horizon in looking back to Earth from an even greater distance. Exploring other planets is the great adventure of our generations and generations of the future.
Working in the field of aerospace science was and is a big challenge for me. You are working close to the limits of technical feasibility. One requirement for having success is teamwork and national and international cooperation. Aerospace science covers a lot of disciplines like structural architecture, fluid- and thermodynamics, electronics, mathematics, physics, etc. Thus, specialists and people who are able to combine all aspects are needed. You have to be open for new ideas and visions.
The current outlook for aerospace engineers and scientists is good. The civil aircraft industry in Europe is growing. Space activities are mainly supported by public money. Thus, the market for engineers and scientists depends on politics and is a little more uncertain. Nevertheless, an education in aerospace science also offers very good chances within other fields of technology.