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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 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 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.

In the frame of the HERMES re-orientation activities, a set of studies has been started to define the most suitable scenario for a Man Transportation System (MTS). The possibility to use a non-winged vehicle to cope with different missions and requirements has been widely investigated, in a competitive study lead by Alenia Spazio as System responsible and performed in collaboration with Dassault Aviation. The study has concentrated first on the selection, from a large number of candidate shapes, of 2 promising vehicle concepts, one in the family of blunt bodies and one in the family of slender bodies. Then the design of the two selected shapes and the assessments of their expected performances have been investigated in greater detail in order to consolidate and validate the conclusions of the trade-offs performed during the first part of the study. This paper focuses on the thermal control issues of the two selected vehicle shapes.

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.

As a consequence of the reduced funding by the ESA Member States contributing to the Columbus and Manned Transportation Programmes, the Columbus Project has undergone two major cost reduction exercises since 1993. An important cost reduction was achieved in mid '93 by downsizing the Attached Pressurized Module (APM) from 8 to 5 Double Racks equivalent length. To reduce the costs further, in 1994 the European space industry took the opportunity of exploiting specific features of the APM common with those of other projects, potential candidates being the Mini Pressurized Logistic Module (MPLM), developed by the Italian Space Agency (ASI) for NASA, or the European developed Russian Data Management System (DMS-R). In addition simplifications in System Function and in the Verification approach and maximum use of Off-the-Shelf and Commercial/Aviation/Military (CAM) hardware were investigated.

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.