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Final preparation and configuration of the Columbus module at the Kennedy Space Center (KSC) required the performance of system level tests with the Active Thermal Control System (ATCS). These tests represented the very last system level activities having been concluded on the Columbus module before handover to NASA for space shuttle integration. Those very last tests, performed with the ATCS comprised the final ATCS Leakage Test, the final calibration and adjustment of the Water Flow Selection Valves (WFSV) and Water On/Off Valves (WOOV) as well as a sophisticated ATCS Residual Air Removal test. The above listed tests have been successfully performed and test data evaluated for verification closeout as well as input delivery for operational Flight Rules and Procedures. Some of the above mentioned tests have been performed the first time hence, a succeeding lessons learned collection followed in order to improve the perspectives of future tests.

Columbus has been delivered to Kennedy Space Center (KSC) in summer 2006 for final integration, test and mission preparation. In the frame of these “last” phase activities also the Active Thermal Control System (ATCS) had to be finalized and prepared for the launch resp. mission. Due to unexpected late failures resp. malfunctions detected on component/unit level of the ATCS, refurbishment, integration / exchange of the relevant components and re-testing of their system level functions had to be done. Moreover, the still outstanding system level fluid leakage test of the ATCS had to be revised and completed. In addition to the required late refurbishment, integration and test activities, in certain cases also operational workarounds had to be evaluated. They should help to cope with similar contingency situations during operation of the ATCS on-orbit.

Verification of the Integrated Overall Thermal Mathematical Model (IOTMM) is one of the last tasks in the thermal and environmental control area of the Columbus module. For this purpose a specific test covering as well thermal-hydraulic performance tests as Environmental Control and Life Support (ECLS) cabin temperature control functions has been defined and performed on the european Columbus Protoflight Model (PFM) in Bremen in 2003. This Environmental Control System test was successful for all Active Thermal Control System (ATCS) related thermal-hydraulic functions and could provide sufficient data for a proper IOTMM correlation. However, it failed to verify the ECLS related functions as cabin temperature control and ventilation. Data, which have been generated during this first test, could not be used for a successful IOTMM correlation related to ECLS subsystem performance and modelling.

The change in mode status of the Attached Pressurized Module (APM), termed a mode transition, is due to the need of changing the APM configuration triggered by nominal or contingency events, i.e: initial system activation and further de/reactivation, payload activation, crew, ground or station initiated mode changes, etc. Past simulations of the APM Cabin Air Loop, for individual operational modes, have been performed by Dornier. This paper presents the results of the hydraulic and thermal analyses of the APM Cabin Air Loop for mode transition with the new version of the European Space Agency (ESA) supported software EcosimPro. The range of analysis has now been extended to long duration simulation of transitions between modes, which was impractical in the past.

In a harmonized ESA/NIVR project the performance of membrane gas absorption for the simultaneous removal of carbon dioxide and moisture has been determined experimentally at carbon dioxide and humidity concentration levels representative for spacecraft conditions. Performance data at several experimental conditions have been collected. Removal of moisture can be controlled by the temperature of the absorption liquid. Removal of carbon dioxide is slightly affected by the temperature of the absorption liquid. Based on these measurements a conceptual design for a carbon dioxide and humidity control system for the Crew Transport Vehicle (CTV) is made. For the regeneration step in this design a number of assumptions have been made. The multifunctionality of membrane gas absorption makes it possible to combine a number of functions in one compact system.

In an on-going harmonized ESA/NIVR project, performed by Stork Comprimo and TNO-MEP, the removal of the carbon dioxide with membranes is studied. The use of membrane gas absorption for carbon dioxide removal is currently hampered by the fact that the commonly used alkanolamines result in leakage problems when using polyolefin membranes. This prevents the use of membrane gas absorption for carbon dioxide in spacecrafts. TNO has recently discovered classes of liquids for carbon dioxide absorption which are suitable for use with cheap polyolefin membranes. This opens the possibility for using membrane gas absorption for carbon dioxide control in spacecrafts. In the project the performance of membrane gas absorption for the removal of carbon dioxide from gas streams having a chemical composition representative of spacecraft conditions are determined experimentally.

A new configuration of centrifugal waste liquid separator is presently under development in Microtecnica. Its main feature is the single shaft configuration, which means only one motor drives both the separator sub-assy and the fan, which is unusual for this class of separator. This paper will describe all the reasons for this selection, the features of the system, the performances and the results obtained at the present stage of development.

The outermost fabric of an astronauts space suit is directly exposed to the various space environmental hazards and therefore has to withstand the various loads arising during EVA operation. In a previous study phase the Outer Fabric for a European Space Suit (OFFES) has been developed using advanced technology and special surface protection components. Different design versions have been manufactured - using 3-D weaving as well as 3-D knitting technology - and were subjected to a test campaign covering the investigation of mechanical/tribological, chemical, thermooptical and micrometeorite and debris (M/D) protection properties of the material. The current phase is concerned with the further development of the fabric for its application on a space suit. For this purpose an arm segment of a thermal and micrometeorite protection garment (TMP) has been manufactured using a further improved version of the OFFES fabrics.

The separation of gases and liquids under microgravity conditions is a common task to be accomplished in Life Support Systems of Spacecraft. Separation has to be achieved in two main domains: water separators separate water from an air stream coming e.g. from the slurper holes of a condensing heat exchanger gas traps have to safeguard sensitive devices in water loops, like e.g. centrifugal pumps or passages with small inner diameter, against blockage by gas bubbles. This paper describes the evaluation of a two-membrane concept fur use in microgravity. The concept originally had been developed for medical application and features a hydrophilic screen for retaining gas bubbles in a water stream; the bubbles are then vented via a hydrophobic membrane to the ambient. Commercial blood gas bubble filters were successfully tested in parabolic flight proving the feasibility of the concept for application as gas trap in microgravity.

During Extravehicular Activities (EVA) an astronaut has to be protected against various external factors ranging from mechanical hazards to solar radiation and micrometeoroids. An important element in this external protection is the outermost fabric layer. It has to ensure the mechanical protection of the pressure retention bladder and at the same time - by its thermooptical properties - plays an important role in the thermal control of the space suit. New weaving and knitting technologies enable the fabrication of so-called 3-D fabrics with interconnected layers and local variation of properties in one manufacturing step. By this a tailored design of protection properties is possible. A study has been performed to define concepts adapted for use on a European Space Suit. Different fabric samples were manufactured and tested, amongst others, for strength, flexibility, puncture and wear resistance, UV stability, flammability, out/offgassing and micrometeoroid protection effctiveness.

In the frame of ESA's Basic Technology Research Programme an integrated Fan-Pump-Separator (FPS) unit, for the European EVA Space Suit System, was developed up to breadboard level. The development was carried out by TECHNOFAN (F) as subcontractor to DORNIER (D) under contract of the European Space Agency. Concept Trade-offs and design definition confirmed the advantages in power, mass and volume of integrating all three functions into a single unit. The unit is driven by one common brushless DC motor. The performance requirements for the three basic functions (oxygen circulation, coolant water circulation and water separation) were derived from the system layout of the life support system for the European EVA Space Suit. The separate functional units were comprehensively tested in preliminary development tests. Final assembly of the functional units led to an integrated breadboard, which was successfully tested.