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In the course of CRYOSYSTEM phase B (development phase) financed by the European Space Agency, AIR LIQUIDE (France) and Astrium Space Infrastructure (Germany) have developed an optimized design of a −183°C freezer to be used on board the International Space Station for the freezing and storage of biological samples. The CRYOSYSTEM facility consists of the following main elements: - the CRYORACK, an outfitted standard payload rack (ISPR) accommodating up to three identical Vial Freezers - the Vial Freezer, a dewar vessel capable of fast and ultra-rapid freezing, and storing up to approximately 900 vials below −183°C; the dewar is cooled by a Stirling machine producing > 6 W at 90 K. The Vial Freezer is operational while accommodated in the CRYORACK or attached to the Life Science Glovebox (LSG). One CRYORACK will remain permanently on-orbit for several years while four Vial Freezers and two additional CRYORACKs support the cyclic upload/download of samples.

In the frame of the CRYOSYSTEM A-phase study financed by the European Space Agency, AIR LIQUIDE (France) and ORBITAL HYDRAULIC-BREMEN (Germany) have been studying a -183°C freezer to be used on-board the International Space Station for freezing and storing biological samples.

As humans move into outer space, need for air, clean water and food require that green plants be grown within all planetary colonies. The complexities of ecosystems require a sophisticated understanding of the interactions between the atmosphere, all nutrients, and life forms. While many experiments must be done to find the relationships between mass flows and chemical/energy transformations, it seems necessary to develop generalized models to understand the limitations of plant growth. Therefore, it is critical to have a robust modelling capability to provide insight into potential problems as well as to direct efficient experimentation. Last year we reported on a simple leaf model which focused upon the mass transfer of gases, radiation/heat balances, and the production of photosynthetically produced carbohydrate. That model indicated some of the plant processes which had to be understood in order to obtain parameters specific for each species.

In the design of fluid systems plumbing for aircraft engines, the designer is continually challenged by the problem of component location and routing. In order to achieve accessibility and maintainability, and to avoid physical interferences, plumbing design is accomplished through extensive graphical projection and mockups. The solution to this problem must also satisfy tubing stress limits, resonant frequencies, bracket or clamping positions available and future space requirements. To facilitate and expedite this design procedure a digital computer technique has been developed which determines the clearances between tubing and other engine components. Though not a substitute for graphical projection, this program provides a means for accurate checking for interference. It also serves a valuable purpose in the storage of previous or alternate plumbing routing arrangements for comparison.

The system that will be presented consists of a Crawling Portable Robot (CPR) for drilling large air frame components as a part of the whole assembly process of fuselage or wing type sub-structures. Currently, the drilling of such components is massively fulfilled manually in a very labour intensive and “craft-based” manner. The operations are conducted in cramped, dangerous conditions and often involve unhealthy postures. The alternative to this situation consists in the use of large fixed-base multi-axis machines mounted upon a foundation on the shop floor. These machines are quite expensive, and also have a number of operational limitations. Because of their large working envelope, it is difficult for these machines to hold close tolerances over the entire range of all movement axes of the machine. Hence, there is a need to probe and calibrate the machine to the workpiece one or more times during work operations with the consequent negative impact in productivity.

A dynamic simulation model has been developed for a vapor-cycle cooling system designed for aircraft applications using the latest technology developments. The heat exchanger models use multiple-, lumped-parameter, fixed-length elements based on coupled thermal and mass storage effects, and flow equations that incorporate the effects of thermal expansion and contraction. This model is developed to include the two-phase constant pressure temperature gradient unique to refrigerant mixtures. The full system model incorporates global mass conservation which is essential for accurate pressure levels and, thus, dynamic response and steady state performance. Phase boundary-based coordinate transformations on the nonazeotropic refrigerant mixture property data result in improved accuracy and computation efficiency. The simulation is developed with modular components with causality defined to minimize connection states and thus execution time.

Cooling detectors down to 0.1K will be of great importance for future far infra red and submillimeter space telescopes during the next few years. This objective can be reached using a Stirling Cryocooler and a Joule Thomson (JT) expansion stage to precool to 4K. The low temperatures are then obtained by an open cycle dilution refrigerator circulating 3He and 4He. This system does not need any cryogenic reservoir and can be launched at room temperature. In this paper, we present the characteristics and performances of the two parts of the refrigerator measured separately, showing the feasibility of such a system. Expected performances of the complete system are a base temperature of 100mK with 100nW heat load and a life time of 5 years with a reasonable gas storage weight (20-50 kg).

This paper describes the development of a packaging technique using the new dual in-line package. Part one tells why this package was developed and gives some advantages this technique has over present trends in packaging. Part two gives a complete explanation and description of the component parts of the package. The third part elaborates on the heart of the package, namely the interconnection matrix. Details are given on converting from a systems logic diagram to a graphic format used in the development of the matrix layout. Part four explains the step by step procedure used in manufacturing the dual in-line module on both the prototype and production level. The fifth and final part of the paper tells of other packaging techniques using as a basic building block, the internal parts of the dual in-line module.

A CELSS has been defined based on current or near-term technology. The CELSS was sized to support the metabolic load of four people on the Moon for ten years. A metabolic load of 14 MJ/person/day is assumed, including an average of 2.6 hr of EVA/person/day. Close to 100% closure of water, and oxygen, and 85% closure of the food loop is assumed. With 15% of the calories supplied from Earth, this should provide adequate dietary variety for the crew along with vitamin and mineral requirements. Other supply and waste removal requirements are addressed. The basic shell used is a Space Station Freedom 7.3 m (24 ft) module. This is assumed to be buried in regolith to provide protection from radiation, meteoroids, and thermal extremes. A solar dynamic power system is assumed, with a design life of 10 years delivering power at 368 kWh/kg. Initial estimates of size are that 73 m2 of plant growth area are required, giving a plant growth volume of about 73 m3.

An examination of the development of intermodal air/surface containerization based to a large extent on the lessons gained in marine containerization and how this experience has transferred to the new opportunities that are apparent for air shippers. The paper examines the history and growing sophistication of air/surface container leasing and how the concept of high-service leasing can be readily applied to air cargo carriers and shippers. A detailed rationale for service-oriented leases spells out the benefits for air shippers who deal with leasing companies including the availability of quality containers; flexibility in acquiring additional containers when required; incerchangeability with other pool customers; and easing of the burdens of container control, maintenance, repair and administration.

Airport land and operational constraints will force future air cargo terminals to assume a new look if they are to accommodate continued air cargo growth. Improved terminal utilization coupled with cooperative airline endeavors in the use of modular container terminals offers a viable solution which can reduce container handling costs by 40 percent and better through economies of scale. Using a building-block approach with innovative and state-of-the-art equipment, a universally applicable container terminal module is derived which can accommodate growth in customer service level as required, and in multiples can accommodate increasing air cargo flow levels. Example module requirements to the year 2005 are derived for representative U.S. cities.

This paper outlines the selection, design, and testing of a prototype nonventing regenerable astronaut cooling system for Extravehicular Activity (EVA) space suit applications, for mission durations of four hours or greater. The selected system consists of the following key elements: a radiator assembly which serves as the exterior shell of the portable life support subsystem (PLSS) backpack; a layer of phase change thermal storage material, n-hexadecane paraffin, which acts as a regenerable thermal capacitor; a thermoelectric heat pump; and an automatic temperature control system. The capability for regeneration of thermal storage capacity with and without the aid of electric power is provided.

As electronic components and circuits get smaller the problems of mounting and interconnecting elements into a system become more difficult. This paper indicates how one packaging concept using a carrier-mother board, rack approach, interconnected by wire-wrap techniques solves some of the problems imposed by these small components. Flexibility, cost, reliability and their influence on the selection of the final configuration are investigated. The application of hot gas soldering for mounting flat packs to carriers is described along with the advantages gained by its use.

This paper presents a novel concept of acclimatized container to increase people comfort in case of temporary housing. It is based on the ZEBRA concept (Zero Energy Building Renewable Addicted) concept studied by Università of Modena e Reggio Emilia. The original concept developed for industrial building has been extended to mobile metallic housing systems such as the containers transported by trucks which are used for troops and military command during field operations. This system does not require any external source of energy. It requires only the presence of a water well or drilling a hole to place inside a closed loop exchanger which is used to stabilize temperature of internal water which is used as a dynamic thermal barrier which maintains in the wellness conditions inside the mobile housing equipment. Energetic costs of this system are related only to the very reduced energy necessary for water pumping operations.

Advanced electrical power conditioning systems for the More Electric Aircraft Initiative involve high currents and high voltages with the attendant waste heat generation and cooling problems. The use of solid state switching devices such as MCTs for these systems will result in power dissipation of several hundred Watts per square centimeter. Conventional forced air or low velocity single phase fluid cooling is inadequate to handle the waste heat dissipation of these high power devices. More advanced and innovative methods of cooling which can use fluids available in the aircraft and also easy to package are sought. A new approach called “venturi flow cooling concept” is described. It is shown that localized cooling up to 200 W/cm2 is possible at the venturi throat region where the MCTs can be mounted. PAO coolant with Pr = 56 at 40°C can be conveniently used in aircraft.

Many components used in the aerospace industry are complex-shaped, without symmetric axes and parallel surfaces. Fabricating and repairing these components often require fixturing system to support manufacturing processes such as drilling, surface finishing, inspections and assembly. Currently available fixturing systems can be divided into dedicated and flexible fixtures. Among these, the flexible fixtures are suitable for rapidly changing fabricating processes and handling several complex-shaped components using same fixturing system. Background research suggested that the pin type fixturing system is the predominant design used in such applications to fix complex-shaped components. In pin type fixturing systems, force is applied to a single point of contact. This increases the pressure applied to the work piece and possibility of damaging these components. Further, conventional pins use rigid designs, which cannot adapt to the shape of the work piece.

In the past testing of airborne electronics equipment has for the most part fallen into the category of either completely manual or fully automatic. While manual test equipment is relatively simple and inexpensive, it is too slow for testing many of today's multiple-output electronic packages. To reduce checkout time, more sophisticated automatic test systems have been built. However, the automated equipment requires elaborate programming and storage facilities, and the overall cost of this equipment tends to be astronomical. This paper presents an examination of current maintenance problems in the Tactical Air Command and investigates problems associated with some of the automatic test systems in use today. The merits of semiautomatic test equipment are discussed as a possible optimum solution to many of these problems. As an illustration, a design problem is presented along with a practical approach and solution.

A review of the progress in the aeronautical and aerospace spares management which has occurred roughly from the mid 1940's through 1963. Areas covered include Commercial Airline, Army, Navy, Air Force and NASA. It includes some of the past history of spares management and improvements gained. The paper covers, in each of the above areas, the range of spares management from provisioning, ordering, inventory control and distribution through packaging and handling. Progress has been considerable over the past 20 years, and it is anticipated that more efficient spares management is imminent as refinements and improvements are continued.

Due to expensive transportation cost, utilization of waste water treatment technologies is regarded as more cost effective than shipping clean water from Earth for long term space missions. As larger than required water treatment capacity is a waste of resources and cost, the relationship among crewmembers and crops water consumption and production, water treatment capacity, water storage tank capacity and water supply required from Earth is explored in this study. Two scenarios and two mission durations are studied to investigate the impacts of crop addition and time length, respectively, on the water subsystem cost. Crops are grown to meet crewmembers' energy requirements. Crewmembers and crops water consumption and production, number of crewmembers and mission type are assumed based on educated guesses and references to documented sources and real life scenarios.