Servicing of the future European stations/platforms through European means

Abstract In order to get a better knowledge of servicing problems and scenarii of the future European In Orbit Infrastructure, CNES (French Space Agency) decided to fund two separate servicing analysis, respectively conducted by Aerospatiale and MATRA. Aerospatiale work deals with several possible manned stations, taking into account a previous study, while MATRA work deals with polar platform aspects. The first part (Servicing of manned Space Stations) deals with a possible optimization of the roles to be played both by the future Ariane 5 launcher in automatic mode and by the Hermes Spaceplane for the servicing of some future manned space stations: the Columbus pressurized module on the U.S. Space Station, a non-evolutive one-module autonomous station and a multi-module one with a growth capability. After having identified the potential cargoes required for the maintenance and servicing of these stations (analysis of payloads, maintenance ORUs, consumales, crew exchange) and the possible frequencies of such a servicing, it is intended to show how it can be achieved through European means. Established scenarii make use of the Ariane 5 launcher combined either with the Hermes vehicle or with an automated payload. Solutions using payload carriers and/or logistic modules are examined, and possible impacts on stations and/or vehicles are identified further, following investigations on orbital transfer operations. The second part (Servicing of polar platforms) describes the possible scenarii of in-orbit implementation and servicing of a polar platform (number of Ariane 5 launches, modes of transfer, type of service vehicles, servicing orbit, …). This part is focused on the in-orbit operation to exchange on ORU (Orbital Replaceable Unit), once both platform and Hermes (or other servicing vehicle) are attached. After a review of the main tasks to be performed and the possible means to be used as manipulator or EVA, the paper describes the scenario (extraction of an ORU, integration of a new one). Moreover, some ORUs, such as sensors and instrumentation payloads, may require a specific in-orbit alignment; the main problems raised by such a requirement are identified.