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The European ARIANE 5 launcher is designed to put a payload mass of about 6.0 t into geostationary transfer orbit. It consists of a lower central stage with two solid propellant strap-on boosters and a single-engined storable propellant upper stage. The ARIANE 5 was successfully launched on October 30th, 1997. This paper deals with the thermal protection of the ARIANE 5 upper stage. The tanks, the actuators, the instrumentation and electronic equipment have to be protected from the heat input of the hot engine nozzle during the 1100 second thrust phase and maintained operational for a further time period for passivation or re-ignition of the engine. The paper provides a short history of the upper stage development and the thermal design for the configuration of the qualification flights. For the production phase the optimization potential with regard to mass saving and simplified integration has been investigated.

With the successful retrieval of EURECA, the EUROPEAN RETRIEVABLE CARRIER, again a long term orbit satellite (11 month in space) is available for the space material community to investigate the influence of low earth orbit environment on materials which stayed in orbit for a prolonged time. EURECA, designed, manufactured and launched to carry out numerous experiments in the fields of fluid- and solar physics, materials science, biology and astronomy under orbital conditions, in parallel presents a huge material expositon experiment in itself, providing detailed insight into the possible orbital degradation mechanisms due to the synergistic effects of atomic oxygen, UV radiation, thermal cycling, high vacuum and micrometeorite/debris impacts. In order to exploit the valuable information, an integrated ESTEC/ERNO team has been established to perform a detailed investigation of the EURECA surface and - as far as accessible -internal structural parts and experiments.

The new European ARIANE 5 launcher being designed to put a payload mass of 6.8 t into geostationary transfer orbit is scheduled to be operational in 1995. It consists of a lower central stage with two solid propellant strap-on boosters and a single-engined storable propellant upper stage. The ARIANE 5 upper stage tank section has to be protected from the heat input of the hot engine nozzle during the 800 second firing period. Furthermore, the tank section and its components have to be thermally controlled for up to 3 hours after upper stage firing in order to maintain all equipment in an operational condition for possible passivation of the stage or re-ignition of the engine. This paper describes the thermal protection system development program with emphasis on the heat shield. The optimization process is shown starting with material selection combined with analysis and is followed by test verification. The foreseen manufacturing and integration approach is outlined as well.

The European Retrievable Carrier (EURECA) is the first European reusable experiment platform, which is scheduled to be transported in 1988 into orbit by NASA's Space Shuttle. EURECA is designed for five free-flying missions in a 500 km and 28.5° inclination orbit, each with a 6-month operational and a 3-month dormant phase. The capabilities of the baseline Thermal Control Subsystem design have been investigated for future missions with regard to extended lifetime as well as applying a purely passive design according to the mission requirement. This paper describes the thermal concept for various EURECA missions expected to be realized in the near future. Moreover, a general outlook on future EURECA flights is presented. The work has been performed under the contract of the European Space Agency (ESA).

The payloads to be flown on the German Spacelab D1 mission in October 1985 located in the Module are thermally accommodated by a combined air/water cooling system, whilst the experiments on the Unique Support Structure are designed for autonomous operation. This paper describes the work performed on the thermal system under contract of DFVLR to satisfy the requirements of the experiments and those of the Space Shuttle.