Saft has signed a contract with EADS Space Transportation to provide flight batteries for the next 30 Ariane 5 launch vehicles, including the latest Ariane 5 ECA satellite launch vehicle, which is capable of placing 10 tonne payloads into orbitThe Ariane 5 ECA represents a major milestone for the European Space Agency (ESA). It has been developed to keep pace with trends in the commercial launch market, especially the need to launch larger and heavier satellites, while reducing launcher production costs. Equipped with the Vulcain 2 main engine and the new cryogenic upper stage (ESCA), it is capable of boosting payloads of up to 10 tonnes into geo-stationary transfer orbit for a single or dual launch project.The generic version of Ariane 5 has already enjoyed 18 successful flights and one world record: the largest telecommunications satellite ever to be placed into geo-stationary transfer orbit - the Thaïcom 4-Ipstar, launched on August 11 2005.For the generic Ariane 5, Saft is providing a total of 18 individual battery systems to power key elements, including the Vehicle Equipment Bay (VEB), which is often called the 'brains' of a launcher. Situated on top of the main cryogenic stage its computer systems provide autonomous control for all the systems required to control a flight throughout its duration, such as Vulcain engine ignition, and the separation of the boosters and storable propellant upper stage.Power for the inertial guidance and control systems is provided by two 60V silver oxide-zinc (AgOZn) primary batteries, each comprising 39 14 PNS cells capable of supplying 17A for 65 minutes. Also in the VEB, four rechargeable 30V nickel-cadmium (Ni-Cd) batteries, each comprising 25 VR1.6CE cells, power the pyrotechnic and safety systems.The EPC main cryogenic stage is essentially an aluminium tank with two compartments: one for liquid oxygen and one for liquid hydrogen. At the base is the Vulcain engine, which operates for approximately ten minutes until the main stage separates. Power for the EPC guidance and control systems is again provided by two 60V AgOZn batteries, while six 30V Ni-Cd batteries power the pyrotechnics - for stage and booster separation - and safety systems.The Ariane 5 EAP solid propellant boosters, attached to both sides of the main cryogenic stage, are the largest solid rocket boosters ever produced in Europe. Each contains around 238 tonnes of propellant and together they provide 630 tonnes of thrust, 92 percent of the thrust needed at lift-off. Two 30V Ni-Cd batteries power the EAP telemetry systems and a further two 30V Ni-Cd batteries power the booster recovery systems that indicate their position when they have fallen back to earth.As well as the more powerful Vulcain 2 main stage engine and enhanced solid boosters, the key element in the Ariane 5 ECA is a new more powerful cryogenic upper stage, powered by the Ariane 4 launcher's HM-7B engine. This requires three additional 40V batteries to power the cryogenic pump that supplies fuel to the engine.All these batteries proved their capabilties in the successful first qualification flight of the Ariane 5 ECA in February 2005, resulting in the EADS Space Transportation's contract to supply all the flight batteries for the Ariane 5 programme through to 2010. These are currently being designed and manufactured at Saft plants in Poitiers and Bordeaux, France.