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The Total Off-gassing test purpose is to determine the identity and quantity of trace gas contaminants offgassed in areas of spacecraft where the crew will breathe the atmosphere. Two different air sampling methods were adopted in parallel during the off-gassing tests on the Multi-Purpose Logistics Modules (MPLM) by Alenia Spazio. The first method, based on NASA (National Aeronautics and Space Administration) requirements, foresees storage of collected air samples into stainless steel pressure cylinders. The second method proposed by ESA (European Space Agency), uses trace contaminants adsorption on Carbopack™ filled ceramic tubes. Sample lines route the samples collected inside the MPLM cabin, to the respective external collection points. Successively, the stored samples are chemically analyzed by Gas Chromatography / Mass Spectrometry (GC/MS) techniques and the module offgassing rates are calculated.

Two-phase capillary loops are being extensively studied as heat collection and rejection systems for space applications as they appear to satisfy several requirements like low weight, low volume, temperature control under variable heat loads and/or heat sink, operation under on ground and micro gravity conditions, simplicity of mounting and heat transfer through tortuous paths. In 1998–2000 Alenia defined and Lavochkin Association developed the Deployable Radiator on the base of honeycomb panels, axial grooved heat pipes and Loop Heat Pipe. It was designed for on-ground testing.

The COLUMBUS Attached Pressurized Module (APM) is the European orbiting laboratory which will be permanently attached to the International Space Station Freedom (SSF). It is designed to provide a range of laboratory facilities in a microgravity environment for payload experiments originating from the international payload-user community. The individual payloads will in general be mounted in payload racks which can be accommodated in fixed positions on the left and right hand sides of the laboratory and in the ceiling. International standard payload racks (ISPR) can be located in any of the SSF laboratory elements and find compatible interface conditions subject to agreements made between the international partners (NASA, NASDA and ESA). The APM design provides a water cooling capability by means of moderate temperature (MT) and low temperature (LT) pumped fluid loops. The cooling loops serve both the APM essential subsystem equipment as well as the payload users.

The Columbus Attached Pressurised Module (APM) Active Thermal Control System (ATCS) water loop collects the APM waste heat and transfers it to the Space Station Freedom (SSF) Central Thermal Bus (CTB). The interface between the APM water loop and the SSF ammonia loops is achieved with two ammonia/water interloop heat exchangers (IH/X), one being low temperature (LT) and the other moderate temperature (MT). The APM internal water loop provides cooling to payload and subsystem users which have varying temperature requirements at their heat rejection interfaces, and can be categorized as cold branch and warm branch users, (e.g. condensing heat exchanger (CHX) and refrigerator are cold branch users, while Avionic heat exchanger (AHX) and furnace payloads would be warm branch users.)

Manned Space Systems are usually designed to support the crew atmospheric conditions equivalent to those at sea level. In phases with frequent Extra Vehicular Activities (EVA), a reduced pressure environment is preferable to facilitate the EVA suit prebreathing procedures. The Columbus Attached Pressurised Module (APM) will face both pressure scenarios during its life. Operation at different pressure levels primarily affects the performance of the Environmental Control System (ECS) of the pressurised elements. A lower air density results in reduced heat exchange, adversely affecting both the crew comfort and the electronics air cooling. This paper reports the results of a study performed to identify the constraints and the numerous potential problem areas related to APM operations at reduced pressure. Effects of the reduced pressure on the environmental parameters have been investigated.

The Mini Pressurized Logistic Module (MPLM) is designed to transport supplies and return cargo requiring a pressurized environment to and from the Space Station Freedom (SSF) via the National Space Transportation System (NSTS) Shuttle. The MPLM provides accommodation for a number of cargo racks, including two Freezer/Refrigerators (F/Rs) and one subsystem rack. The maintenance of the habitable conditions for the crew and the control of the MPLM thermal environment are carried out by the Environmental Control and Life Support System (ECLSS) and the Thermal Control System (TCS). The ECLSS and TCS functional concepts are tailored to the peculiarities of the MPLM design, based on mass and volume minimization, maximum simplification and exploitation of the resources available at the SSF interface.

The Attached Pressurised Module (APM) is the European element of the NASA Space Station Freedom (SSF). The environmental control of the APM is obtained through the combined effort of the Water Loops of the Thermal Control Subsystem (TCS) and the Cabin and Avionics Loops of the Environmental Control and Life Support Subsystem (ECLSS). Although the specific functions of ECLSS and TCS are separately verified at subsystem (S/S) level, their overall qualification is completed only after having carried out the functional and performance verification of the integrated Environmental Control System (ECS) inside the APM. To this purpose too, an APM Engineering Model (EM) development has been included in the programme. The Engineering Model is the element prototype, fully representative of the APM Flight Model (FM) but for the quality of the EEE components, as they are requested to be MIL-grade but not Hi-Rel.

Microorganism accumulation and growth onboard a spacecraft may impact adversely on crew efficiency and safety as well as system, subsystems and payload. The results of test campaigns performed at Alenia Spazio in Summer 1993 are reported here. From them, some simple and effective prevention methods to be applied during the manufacturing and integration phases of a pressurised spacecraft have been identified and are here discussed. Although data obtained from Earth experience may be considered useful, it is uncertain and unfit for space station operational lifespan. Therefore, it is necessary to build a model of the phenomenon, able to provide a series of quantitative data as a function of different parameters related to environmental characteristics, crew, and on-board activities.

At present, limited tools are available to model atmosphere control and supply systems simply, in order to allow quick design assessments based on analytical performances. In this context, the utilization of PC based ESACAP adapted as an Atmosphere Control and Supply (ACS) simulation tool is described. The analyses results shown in this paper refer to the activities of MPLM baseline re-definition carried out in accordance with the Space Station re-configuration. As a consequence, in several cases the described analyses reflect conservative assumptions and have been performed in a parametric way so as to take the uncertainties into account.

The Mini Pressurised Logistics Module (MPLM), a cooperative project between NASA and ASI that will be designed, developed, produced, integrated and delivered by Alenia, is a pressurised volume devoted to the resupply and return of Space Station (SS)containerized cargo requiringapressurised environment, via the National Space Transportation System (NSTS). As a servicer for the SS, the MPLM will have to accomplish several trips between Earth and SS in support of logistic needs. Since the active payloads launched with MPLM (freezers and refrigerators) require resources during the transportation phase inside the NSTS, the MPLM has the peculiar capacity to exchange power, data and fluids with the Orbiter before docking to SS. Once docked to SS, the MPLM will be required to provide its full performance, making use of the resources available from the SS Node; nevertheless, in this phase some of the MPLM functions are demanded from the SS.

The redesign of Space Station Freedom (SSF) and the requirement of the Columbus programme board to reduce costs have led ESA to change the design and development strategy of the Attached Pressurised Module (APM). A revised APM reference design for integration with the SSF Alpha has been produced with sufficient flexibility to allow adaptation as part of a global space station or to permit operations as part of a European Free Flyer. The main objectives of the redesign have been to simplify the design, reduce the costs and provide increased autonomy from the SSF. The key groundrules for the redesign have been an AR5/ATV launch from the Centre Spatial Guyanais (CGS) into an orbit inclined at 51.6 degrees. The APM has a length equivalent to 5 double racks and a net launch mass of 1200 kg. It will be delivered to the SSF at an altitude of 407 km for a 10-year operational life. Safe disposal will be by ATV.

The Columbus fire suppression procedure is based on a centralized CO2 distribution system which injects the CO2 stored in a tank into the volume where the fire has to be extinguished. The fire is detected in each volume by means of the so-called REP (Rack Essential Package), which contains a fan and the smoke sensor. In order to assess the Fire Detection and Suppression design concept and to identify possible critical areas, Alenia Spazio - with the support of Flowsolve UK, and on behalf of EUROCOLUMBUS - has performed an analysis using a Computational Fluido-Dynamic (CFD) tool. The rack containing the water pump assembly and other electronic equipment has been chosen for the study. As far as the Fire Detection is concerned, the simulation intends to predict the flow field established in the rack by the ventilation system and the transport of smoke by this velocity field from a supposed point source.

A Human Factors Engineering (HFE) analysis has been involved in the design process of the Mini Pressurized Logistics Module (MPLM) for the International Space Station (ISS) since the beginning, as an integrated part of the design support activities. The support of HFE in the configuration process has been directed towards the optimization of the MPLM design through the analysis and evaluation of all the interfaces occurring in the module - nominal and non-nominal - between the crew, the system and the subsystem equipment. In order to identify and analyze all the crew interfaces occurring inside the module, a systematic approach, involving different disciplines, is necessary. The integration of three different tools such as computer simulation, task analysis and mock-up test activities has been employed as an organic unit, in order to establish a comprehensive collection of useful data.

The MPLM (Mini Pressurized Logistic Module) is one of the Elements constituting the ISSA (International Space Station Alpha). With respect to the other Elements, the MPLM is not permanently attached to the ISSA, but it is transported by the Orbiter several times from/to the Earth, since its primary use is to resupply and return cargos. The MPLM capability to support the logistic flights is guaranteed during several mission phases (ground, Orbiter transportation, on-orbit docked to the Station). Since the installed cargo can be passive or active, the required MPLM functions are based on the actual flight. This paper presents an overview of the activities performed in Alenia Spazio to identify the criticality and peculiarity of the MPLM mission scenarios from the thermal point of view. The best technical solutions, foreseen up to now, have been implemented in the design to guarantee the reliability requested by such an important and unique Space Station Element.

Under the guidelines established by the European Space Agency (ESA), a specific effort was devoted to define the preliminary design concepts for a Crew Transport Vehicle (CTV) compatible with the Ariane 5 launcher. The mission objectives of this vehicle include the possibility of transporting 4 people (and a limited amount of pressurized payload) to the International Space Station Alpha (ISSA), and returning them to Earth safely. Different options were identified at system level, however a modular vehicle was commonly adopted: a Crew Module (CM) designed to withstand the typical phases of the atmospheric re-entry and provide an adequate environment for the crew during all the mission a Resource Module (RM) envisaged to provide the propulsion provisions for orbital transfer and deorbiting; in addition it carries all the necessary resources to support the mission from lift-off until separation from the CM.

In the overall planning of a manned mission to Mars, all the issues related to human involvement are critical. To a certain extent, they dictate the most severe constraints on the mission scenario and spacecraft architecture. Despite this unanimously recognized importance, limited efforts have been devoted up to now to dedicated research activities on human-related aspects, partially neglected w.r.t. more technical areas like orbital dynamics, propulsion, power generation, etc. This paper summarizes the major results of a survey on the human factors of long duration missions performed by Alenia Spazio in the frame of an ESA study, MARSEMSI, whose aim was to identify possible scenarios and related infrastructure requirements for a manned mission to Mars.

Thermo-hydraulic mathematical models of manned modules of the International Space Station [ISS] require to simulate also air-vapour flow in Environmental Control Systems [ECS] circuits. Although this can be obtained with available S/W, a complementary solution was developed, in order to overcome some S/W limitations and to ease exchange of models. It consists of a set of FORTRAN subroutines, that can be added to ESATAN/FHTS and SINDA/FLUINT thermo-hydraulic models for dry air, and simulate the effect of vapour in the airflow.