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The Globalstar program schedule requirements calls for a very high production rate: 48 satellites -plus a minimum of 8 spares -have to be integrated, tested, and launched in less then two years with a production rate of four satellites per month. New design solutions, assembly process and testing techniques have been developed to achieve this goal because the classical spacecraft assembly, integration, and test (AIT) approach would have been impractical to achieve the required satellite production rate. At the same time production flow considerations and production rate requirement led to a satellite AIT facility design based on the 'Island Concept', where the satellites are rolled and built along the various islands. This is an innovative solution with respect to the present traditional approach that foresees the spacecraft built and kept in a fixed stand. This paper presents the Alenia Spazio approach for the assembly, integration, and test of the Globalstar satellites by highlighting the techniques and methodology used to cope with the required production rate far above the present norm of space industry. (Author) ABSTRACTGlobalstar is an international program aiming to provide a worldwide communication service, including mobile and fixed voice and/or data messaging and user position location. Globalstar system includes a space segment composed of a 48 satellites constellation placed on 8 orbital planes with 6 satellites each, operating at 1400 Km altitude orbit. Such constellation is planned to be preoperational on mid 1998 and fully operating by beginning 1999.In the frame of this program, Alenia Spazio has the responsibility of integrating and testing the Qualification Model and all the Flight Models satellites constituting the space segment constellation. TheGlobalstar program schedule requirements calls for a very high production rate: 48 satellites -plus a minimum of 8 spares -have to be integrated, tested and launched in less then two years with a production rate of four satellites per month.New design solutions, assembly process and testing techniques have been developed to achieve this goal because the classical spacecraft assembly, integration and test (AIT) approach would have been impractical to achieve the required satellite production rate. At the same time production flow considerations and production rate requirement led to a satellite AIT facility design based on the "Island Concept", where the satellites are rolled and built along the various islands. This is an innovative solution with respect to the present traditional approach that foresees the spacecraft built and kept in a fixed stand. This paper will present the Alenia Spazio approach for the assembly, integration and test of the Globalstar satellites by highlighting the techniques and methodology used to cope with the required production rate far above the present norm of space industry.

COSMO-SkyMed di Seconda Generazione (CSG) is the Italian satellite system for Earth observation composed of two satellites embarking a high resolution Synthetic Aperture Radar. CSG is the follow-on of the dual-use COSMO-SkyMed mission, aimed at providing operational continuity with increased performance, flexibility and ability to respond to updated civilian and defence user needs. CSG programme will encompass the necessary upgrading of the ground segment and of the Integrated Logistic Support and Operations segment, as needed to enhance the system capability to manage and satisfy heterogeneous and complementary dual use requirements. The experience gained with the operational exploitation of the first generation system shows that users have various needs according to their domain of belonging (defence, civilian institutional, civilian scientific and commercial). These needs have been continuously monitored and reviewed during the development of the system. In particular, during the Phase C, the mission requirements have been refined as a result of: an iterative process involving the Civilian and Defence Final Users; the exploitation of the bandwidth widening foreseen by International Telecommunication Union for Earth observation in X band; the introduction of new and innovative acquisition modes; the Concurrent Engineering with the currently operational first generation system; the evolution of the agreements between the Italian Space Agency (ASI) and Italian Minister of Defence (It-MoD). The iteration with the Final Users allowed a significant improvement of the requirements in terms of provided services, leading to the introduction and the definition of new asynchronous services, namely the "Very Urgent" and the "Last Minute Planning", which provide the Users with the possibility to serve also last minute requests. Due to the ASI/It-MoD agreements evolution, new concepts for the programming rights have been introduced on the basis of the optimisation of the system resources exploitation improving also the fairness of the resource usage among all the Partners (Civilian and Defence). As regards the acquisition modes, the capability to serve more products in a specified area has been achieved by a state-of-the-art exploitation of both instrument and platform agility.