THE LAUNCHER ARIANE 5 ECA

The launcher Ariane 5 ECA represents a major milestone for the European space industry. The new generation launcher was developed to keep pace with trends in the commercial launch market, especially larger and heavier satellites, and to satisfy governmental needs. Equipped with the Vulcain 2 main engine and with the new cryogenic upper stage ESC-A the launcher is capable of boosting up to 10 tonnes into geostationnary transfer orbit (GTO) for a single or dual launch (two satellites at once). Using a reignitable storable propellant upper stage it can also carry the ATV towards the International Space Station into low Earth orbit (LEO). The increased-performance Ariane 5 ECA is now in full commercial service following the successful flight 164 on February 12th, 2005. The next ECA flight, which is both the last qualification and first commercial flight, will take place in summer this year.

EADS SPACE Transportation has built up extensive expertise, unrivalled in Europe, as prime contractor for large-scale strategic space programmes. This position reflects its capability to lead a team of companies offering the wide range of skills and expertise needed to design and develop such complex projects.

Starting with the next production batch of Ariane 5 (PA batch), EADS SPACE Transportation is single Prime Contractor for the Ariane 5 system. As such it is responsible for the delivery to Arianespace, who commercialises the launches of satellites from the European spaceport of Kourou in French Guyana, of the complete and fully tested launch vehicle, and manages all the contracts associated with its manufacture. The company also supplies all elements for Ariane 5, including the stages manufactured in its facilities at Les Mureaux (France), Bremen (Germany) and Kourou (French Guyana), the equipment bay, the flight software as well as numerous sub-assemblies.

Furthermore, EADS SPACE Transportation is becoming the sole point of contact for the European Space Agency for future developments of the launcher fulfilling also in this domain the role of single Prime Contractor.

EADS SPACE Transportation has the multidisciplinary expertise needed to handle such a complex programme:

EADS SPACE Transportation is responsible for all stages of Ariane 5, which comprises the main cryogenic stage, the solid boosters and the upper stage versions.

The main stage is integrated at the company’s vast Les Mureaux complex near Paris. On this complex is located Cryospace, a joint venture of EADS SPACE Transportation and Air Liquide, which produces the cryogenic propellant tanks for the stage. Also nearby is the functional simulation facility, where EADS SPACE Transportation developes the launcher’s electrical system and software, as well as its guidance-flight control and navigation system.

To ensure safety, the solid-propellant boosters are manufactured at the launch site in French Guyana. EADS SPACE Transportation integrates these huge strap-on boosters at the Guyana Space Centre, starting with the MPS solid propellant motor delivered by Europropulsion, and adding electrical, pyrotechnic, hydraulic, parachute recovery as well other elements delivered from Europe. Ariane 5 marks the first time that a major part of an Ariane launcher is constructed in French Guyana. A complete Ariane 5 “assembly line” and launch system was built in French Guyana from 1988 to 1996. It includes not only the production facilities for the solid boosters, but also assembly buildings for launcher components shipped from Europe, and all payload-processing facilities.

The Ariane 5 ECA upper stages are manufactured in the EADS SPACE Transportation site of Bremen, northern Germany. Today, several upper stages can be assembled simultaneously. The location of Ottobrunn, near Munich, together with the other German site, Lampoldshausen, provides the thrust chamber for the Ariane 5 main engine Vulcain 2 and the Aestus engine for the storable propellant upper stage version.

International competition in the launch services market heats up, with Russian and Ukrainian launchers and with the new-generation American heavy lifters. The latter are advantaged by substantially higher domestic market compared to Europe. To guarantee an independent access to Space, the European Space Ministers decided further investment to enhance the competitiveness of the Ariane system.

The European space industry must meet this challenge by sustaining Ariane’s commercial leadership, which will to a large extent depend on decreasing the launcher’s production costs and easier organisation structures. For that reason, EADS SPACE Transportation became the single prime contractor of the Ariane 5 programme.

As industrial leader, EADS SPACE Transportation oversees henceforth the European cost reduction initiative by co-ordinating the actions of European partners, and enhancing production capabilities. Industry is engaged to reduce production costs significantly, of about 30%, starting with the next batch of production (30 vehicles).

The new launch vehicle version offers a payload capacity of up to 10 tonnes for a dual launch into GTO. It relies on proven technologies and incorporating the long experience of previous programmes. Main parts of the launcher are EADS SPACE Transportation products:

L’Etage Principal Cryotechnique (EPC) ou étage central développé par EADS SPACE Transportation, est essentiellement constitué d’un grand réservoir en alliage d’aluminium, d’un bâti-moteur transmettant la poussée du moteur cryogénique à l’étage et d’une jupe avant, assurant la liaison avec le composite supérieur et transmettant la poussée des deux étages d’accélération à poudre.

Le réservoir est formé de deux compartiments contenant 174 tonnes d’ergols cryotechniques à très basse température. Le moteur cryotechnique, dénommé Vulcain 2, peut être dirigé suivant deux axes pour le contrôle du vol via le dispositif de commande du moteur. Il fournit une poussée d’environ 135 tonnes.

L’étage central opère en continu pendant 530 secondes, procurant la plus grande partie de l’énergie cinétique requise pour le placement d’une charge utile en orbite. Lorsqu’il s’éteint, le lanceur se trouve à une altitude de 130 à 420 kilomètres, en fonction de la mission. Cet étage n’est pas satellisé.

The main cryogenic stage (EPC), or core stage, developed by EADS SPACE Transportation in Les Mureaux primarily comprises a large aluminium alloy tank, a thrust frame that transmits the engine’s thrust to the stage, the cryogenic main engine and a forward skirt, which interfaces with the upper composite and transmits the thrust from the two giant solid boosters.

The tank comprises two compartments containing 174 tonnes of very low temperature cryogenic propellants. The cryogenic engine, so-called Vulcain 2 can be steered in two axes for flight control, via the engine actuation unit. It delivers about 135 tonnes of thrust.

The core stage operates continuously for 530 seconds, providing most of the kinetic energy needed to place a payload in orbit. When it shuts down, the launcher is at an altitude of 130 to 420 kilometres, depending on the mission. This stage is not placed into orbit.

The two solid boosters (EAP), also developed by EADS SPACE Transportation in France are the largest solid rocket motors ever built in Europe. Each of the two solid boosters (EAP) contains some 240 tonnes of solid propellant. The motor comprises a casing made of seven steel cylindrical sections, and a nozzle mounted on a flexible bearing, that can be steered up to 6 degrees by the nozzle actuation unit. The propellant is loaded in three segments.

Each solid rocket motor delivers thrust ranging from about 540 tonnes at lift-off to a maximum of 600 tonnes (1,320,000 lb.). Each motor generates as much thrust as an Ariane 4 at lift-off. The two solid boosters are ignited a few seconds after ignition of the main cryogenic stage, to make sure that the main engine is operating correctly.

With a combined thrust of 1,200 tonnes the two solid boosters provide some 90% of the total lift-off thrust. They burn for about 140 seconds. After burnout, they are separated from the main stage by a pyrotechnic system at an altitude of 55 to 70 kilometres (depending on the mission). They continue on a trajectory peaking at 80 to 140 kilometres, then deploy parachutes and fall back into the sea about 150 kilometres from the launch base. They are regularly recovered for inspection and analysis.

The brand-new cryogenic upper stage, ESC-A, developed by EADS SPACE Transportation in Bremen completes the orbital injection of the payload(s) into the targeted orbit(s) and ensures payload separation and orientation. Carrying 14.4 tonnes of cryogenic propellants (liquid oxygen and hydrogen), this stage operates for about 1,000 seconds on the GTO mission. It uses many elements of Ariane 4 third stage, the so-called H-10 and its HM-7B which delivers vacuum thrust of 65 tonnes. It is also equipped with a hydrogen tank of brand-new design and built on a new graphite interstage skirt of 5.4 m in diameter developed by EADS Casa Espacio. The nozzle of the HM-7B engine is gimballed in two axes for thrust vector control. ESC-A uses a cold gas-based attitude control system, providing roll control during its powered phases and attitude control of the upper composite during payload release.

The vehicle equipment bay (VEB) developed by EADS SPACE Transportation is composed of a lightweight graphite cylindrical structure and a cone supporting a payload adapter and the upper stage. The VEB contains most of the flight control and telemetry equipment and is also equipped with high-performance inertial systems based on one single three-axis rate sensor.

Speltra, the French acronym for Ariane launch external support structure, enables the simultaneous launch of several payloads. For launch, the different payloads are mounted either on or inside the Speltra, depending on their shape and mission requirements.

The Sylda dual launch system also enables the simultaneous launch of two payloads. It is an internal structure, located inside the fairing. Depending on the satellites’ shapes and mission requirements, they are placed on top of or inside the Sylda. It is available in different heights, to make optimum use of the upper part of the launcher.

The cone-shaped fairing protects the payload during its passage through the atmosphere, while also maintaining the required launcher’s aerodynamics. It is released about 200 seconds after lift-off, at an altitude of approximately 110 kilometres. The Ariane 5 fairing is built by Oerlikon Contraves, with the pyrotechnic separation system made by EADS SPACE Transportation. Three different fairing models exist: short, medium and long.

EADS SPACE Transportation is the European specialist for access to space and manned space activities. It develops and produces Ariane launchers, the Columbus laboratory and the ATV cargo carrier for the International Space Station, atmospheric re-entry vehicles, missile systems for France's deterrent force, propulsion systems and space equipment.

EADS SPACE Transportation is a wholly owned subsidiary of EADS SPACE, which is dedicated to providing civil and defence space systems. In 2004, EADS SPACE had a turnover of €2.6 billion and 11,000 employees in France, Germany, the United Kingdom and Spain.

EADS is a global leader in aerospace, defence and related services.

In 2004, EADS generated revenues of €31.8 billion and employed a workforce of more than 110,000.

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