The Galileo constellation is ESA’s satellite navigation system and is expected to be completed by 2020. Galileo will provide Europe with an alternative to the American GPS and Russian GLONASS constellations, but will be interoperable with both systems.
The Ariane 5 ES (Evolution Storable) has an estimated LEO launch capacity of 21,000 kg (46,000 lb). It includes all the performance improvements of Ariane 5 ECA core and boosters but replaces the ESC-A second stage with the restartable EPS used on Ariane 5 GS variants. It was used to launch the Automated Transfer Vehicle (ATV) into a 260 km circular low Earth orbit inclined at 51.6° and has been used 3 times to launch 4 Galileo navigation satellites at a time directly into their operational orbit. The Ariane 5 ES flew 8 times from 2008 to 2018 with no failures.
