Geostationary communication satellites are classically delivered into the elliptical Geostationary Transfer Orbit (GTO). A large portion of the satellite's propellant is used for the transfer manoeuvre to Geostationary Orbit (GEO) and the satellite bus design is largely driven by the accommodation of propellant. Currently new satellite propulsion systems are under study, which potentially allow a more advanced bus design. The most radical solutions are satellites using electric propulsion systems not only for the orbital life phase, but also for a part of the transfer to GEO. These propulsion systems have specific impulses, characterising the system's efficiency, far beyond chemical systems and thus save mass. The problem is the low thrust level of such systems, which extends the transfer time to GEO and requires optimisation of the insertion orbits to be provided by the launcher. For the launch of such satellites, different initial orbits were studied by Astrium. Strategies comprise the launch into Medium Height Earth Orbits (MEO), Super GTO and GTO PLUS. To most of the new insertion orbits ballistic phases and upper stage re-ignition become mandatory. As there will be at least a long transition phase from chemical to electric satellites a mixed dual-launch into with a chemical and an electric satellite on a second orbit may occur, requiring an optimised injection strategy for the launcher. Besides the use of a re-ignitable upper stage, concepts with a dedicated transfer stage, were studied. The objective of the study carried out at Astrium was to assess the interest of electric propulsion for GEO satellites and the impacts on satellite and launcher. A further objective was to analyse whether Ariane 5 is well adapted to the launch of full electric satellites. Astrium Space Infrastructure builds the EPS (Storable Propellant Stage) upper stage, the AESTUS engine, the Vehicle Equipment Bay (VEB) and develops the ESC-A (Cryogenic Upper Stage) of Ariane 5. Furthermore Astrium provides thrust chambers and equipment for other Ariane 5 stages. Ariane 5 is a programme of the European Space Agency ESA. ESA has delegated the programme management to the French National Space Agency CNES.
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