An upgradable launcher
Two evolution programmes, Ariane 5 Evolution initiated in 1995 and Ariane 5 Plus in 1998, developed new variants of the launcher with increased lift capacity.
These upgrades were geared towards boosting performance for launches into geostationary transfer orbit (GTO). Improved performance was obtained by optimizing the lower stage composite with a new, more powerful Vulcain 2 engine, more propellant mass in the EAP solid booster stages and a lighter internal payload bearing structure for dual launches.
The launcher’s generic upper stage was replaced with a cryogenic upper stage offering increased performance to enable Ariane 5 to adapt to a diverse range of payloads, especially for orbiting heavier telecommunications satellites.
Ariane 5 ECA was thus equipped with a cryogenic upper stage called ESC-A, offering a lift capacity of 9.4 tonnes into GTO.
The new launcher failed on its maiden flight on 11 December 2002 when the nozzle of its Vulcain 2 engine ruptured. After exhaustive checks and some improvements, the launcher successfully completed its qualification flight on 12 February 2005.
Ariane 5 ECA qualification flight on 12 February 2005. Credits: CNES/ESA/Arianespace/CSG Service optique, 2005
The Ariane 5 Evolution family also includes the ES variant with a storable-propellant upper stage derived from the upper stage of the generic Ariane 5, enhanced to enable several restarts after ballistic flight phases. On 9 March 2008, this variant successfully launched the Automated Transfer Vehicle (ATV) designed to resupply the International Space Station (ISS), with a cargo capacity of 20 tonnes.
Ariane 5 Infrastructure and ARTA
A series of support projects were decided in 1995 to optimize the Ariane 5 organization. The Ariane 5 Infrastructure project got underway in 1996.
Its initial goal was to assure the continued operation of Europe’s launcher system during the transition from Ariane 4 to Ariane 5. Since 2002, it has also made upgrades at the Kourou launch base.
Vulcain 2 engine on Ariane 5 ECA. Credits: CNES/ESA/Arianespace/CSG Service optique, 2006
Since 1996, the ARTA programme (Ariane Research and Technology Accompaniment) has sought to sustain Ariane 5’s long-term operability. Its goal is to verify reliability and maintain performance, while qualifying all upgrades to the launcher. ARTA also addresses unexpected technical events related to equipment design, during both ground and flight tests.
ARTA encompasses a range of activities including equipment testing, evaluations and maintenance of test facilities. CNES had technical and financial oversight responsibility for this ESA programme up to 2007.
Looking to the future
Ariane 5 ECA is currently Europe’s workhorse launcher, but increased performance is now needed to respond to evolving payload requirements.
The ESA Ministerial Council meeting in November 2008 decided to develop an enhanced variant of the launcher dubbed Ariane 5 ME—for Mid-life Evolution—that would not only boost performance but above all enable more complex missions using a restartable upper stage powered by the new Vinci engine.
In 2014, Europe dropped the Ariane 5 ME programme in favour of reinventing the venerable launcher once again with Ariane 6. This new launcher designed by teams from CNES, ESA and industry will be tailored to launching government and commercial satellites, offering 2 variants—Ariane 62 and Ariane 64—with a restartable upper stage and lower production costs. It could be ready to make its maiden flight from the Guiana Space Centre (CSG) in 2020.
Looking beyond Ariane 6, engineers are already at work on new generations of launchers using new modes of propulsion—pulse detonation, solar thermal and electric—particularly for upper stages.With crewed or unmanned exploration of the solar system now increasingly a factor to be considered for the future, launch capabilities will need to be rethought or improved in line with mission goals.