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CryoSat is the first satellite of ESA's Living Planet Programme realised in the framework of the Earth Explorer Opportunity Missions. CryoSat is a radar altimeter mission dedicated to determine trends in the ice masses of the Earth. The overall spacecraft configuration was driven by the budget constraints applicable for the opportunity mission, the high inclination orbit with drifting orbit plane and the stringent stability requirements for the radar altimeter antennas. Innovative thermal design solutions were needed for the following items: The instrument antennas have to comply with very stringent pointing stability requirements. The star trackers need to be mounted at a thermally adverse position and still have to be maintained on low temperature levels.

The launch and activation of ESA's Columbus module in early 2008 marked the completion of more than 10 years of development. Since then the Columbus ECLS is operating, including its major European ECLSS assemblies such as Condensing Heat Exchanger (CHX), Condensate Water Separator, Cabin Fans and Sensors. The paper will report the experiences from the first year of operations in terms of events, failures and lessons learned. Examples of this is the description of some off-nominal situations (such as Condensate Removal and IMV Return Fan failure, and relevant troubleshooting), and the preparation to Columbus Reduced Condensation Mode, as requested by NASA in order to minimize the crew time needed to empty Condensate Water Tanks in US Lab.

The Columbus Orbital Facility (COLUMBUS) is the main European contribution to the ISS. Its Temperature and Humidity Control (THC) subsystem consists of the Condensing Heat Exchanger and Filter Assembly (CHXFA), the Condensate Water Separator Assembly (CWSA) and the Cabin Temperature Control Unit (CTCU). The paper provides a description of the THC subsystem and its equipment focusing on the humidity removal function which has shown to be the major design challenge. Design solutions have been realised by optimising all equipment of the THC with respect to its system needs. Test results both on equipment and on THC subsystem level are presented demonstrating that the humidity removal performance is adequate to meet the system requirements in the wide operational range of COLUMBUS.

In the range of the Columbus Orbital Facility (COL) program, the European contribution to the International Space Station (ISS), DASA Dornier developed and qualified four new supporting devices for the Environmental Control and Live Support System (ECLSS) as listed below: 1. The Vacuum & Venting Pressure Sensor (VVPS). Based on the Pirani principle, it utilizes the pressure dependence of the gas thermal conductivity. 2. The Humidity Sensor (HS) provides information for the Thermal & Humidity Control System (THC). It works according to the dew point principle, guaranteeing a long stability over at least 10 years. 3. The Air Flow Sensor (AFS), working according to the hot wire anemometer principle, is dedicated to identify low air flow conditions. 4. The Waste Gas Line Shut-Off Valve (WLSOV), a DC motor driven ball type vacuum valve, was adapted to the space station requirements (e.g. noise and micro-g).

Metop (METeorological OPerational satellite) is a series of three satellites designed to monitor the climate and improve weather forecasting. This paper describes the thermal analysis, thermal testing performed, and relevant lessons learned. For the thermal analysis campaigns it focuses on: exchange and correlation of reduced thermal mathematical models established in various software formats sizes and content of the models, in particular automatic generation of reduced models from the detailed models uncertainties definitions of thermal interfaces The lessons learned from the thermal testing campaigns apply to: selection of test environment, using solar simulation and/or infra-red techniques selection of test cases based on thermal design driving parameters and/or test chamber capabilities adequate instrumentation (i.e. thermocouples, test heaters) for all critical components (un)expected events e.g.

In 1995 the European Space Agency did award a C/D Contract for the design & development of an ECLS Subsystem for the Multi Purpose Logistics Module (MPLM) to Astrium’s ECLS ‘Center of Competence’ that built the ECLSS for Spacelab already. Actually first MPLM modules were successfully flown to the ISS with the Astrium built ECLSS qualified as ‘excellent’ by the crew having asked permission to sleep in there. In parallel the design and development of an ECLS for Europe’s Columbus module did commence and is actually close to completion. In view of the above a broad set of qualified and even space proven ECLS equipment is now ‘on-hands’ to thoroughly compose respectively derive the ECLS subsystems of future applications e.g. HabModule, CRV and Space Hotel at a limited delta design and validation effort thus fitting into the tighter financial budgets of the manned space programs to come.

The Herschel satellite is a space based telescope designed for the investigation of sub millimeter radiation from astronomical objects. The cryogenic system is an essential part of the telescope’s Extended Payload Module (EPLM). The cryogenic system has to provide an environment of sufficiently low temperatures to assure the proper functioning of the scientific payload. Main component of the cryogenic system is the cryostat, a huge vacuum vessel (see: Figure 1) with various cryogenic components inside. In order to qualify the components of the cryogenic system, multiple tests such as leak tests, thermal cycle tests, pressure cycle tests and vibration tests are performed. In this paper the test program for two cryo components, the rupture disc and a safety valve is discussed. The testing philosophy is presented and selected results of tests at ambient and low temperatures are shown.