Airbus Defence and Space

Ariane – a family matter

The Ariane success story has been founded on two launchers sufficiently well designed to allow for their progressive adaptation to meet the demands of an ever-changing market. Ariane 4 was the outcome of its predecessors, Ariane 1, 2 and 3. With Ariane 5, a new family emerged, the next version of which will be the Ariane 5 ME.

When the new European launcher came into being on a French space agency drawing board in 1972, it was no more than a Europa 3 substitute launch vehicle, the design of which was based on existing technical solutions – a first-stage concept devised at the ballistics and aerodynamics research laboratory LRBA* with engines under development at SEP**. The aim was to replace, at lowest cost, the Europa 3 which Europe was having difficulty in progressing via the European Launcher Development Organisation (ELDO) following the Europa 1 and Europa 2 failures. So as to avoid any further reference to Europa, the ‘E’ of the code name E-3S was changed to ‘L’ to give L-3S. This would ultimately become Ariane 1.

The first version was consequently based on Europa 3 specifications, with a performance of 1.3 tonnes to geostationary transfer orbit (GTO), in order to match the American Atlas Centaur launchers. Replacement of the HM-4 cryogenic engine of the third stage with the HM-7 led to a rapid increase in performance to over 1.8 tonnes to cater for the upcoming generation of Intelsat 5 satellites.

Europeanised by the skin of its teeth at the Brussels Ministerial Conference on 1 August 1973, in 1979 the Ariane programme achieved the impossible – delivery of an entirely new launcher to the launch pad, on schedule and inside the budget envelope agreed six years earlier. Ariane was born under a favourable star. Ariane 1 lifted off at Christmas Eve 1979 to place an instrument capsule with a mass of 1,645kg, the heaviest payload launched by Europe at that time, into orbit.

Dual launches and modularity

Even before the first Ariane launch, improvements to the launcher had been under examination since 1978. To establish a competitive position, Ariane had to be able to execute dual launches. Using a SYLDA dual structure developed by Aerospatiale, Ariane 1 could carry two satellites of up to 700kg each. However, satellites of almost 1,200kg were just around the corner. So, with a stretched cryogenic third stage, Ariane 1 became Ariane 2. The addition of two solid propellant boosters then resulted in Ariane 3. On its first flight, on 4 August 1984, Ariane 3 beat the record for the heaviest civil payload placed into orbit previously held by the Americans, with a mass value of 2,576kg.

This was just a beginning. Other launchers were appearing on the drawing boards, incorporating a stretched first stage designed to carry 50% more fuel and accompanied by solid and liquid propellant boosters. There were six different modular versions of the new Ariane 4 launcher, capable of placing payloads of up to 4.4 tonnes into GTO. Development of Ariane 4 was decided on in 1982, and the launcher flew for the first time on 15 June 1988. In the meantime, the American Shuttle had experienced a major failure with the explosion of Challenger just after lift-off on 28 January 1986. The Shuttle would indeed return to flight, but its commercial career was over, and as the production lines for the American Delta and Atlas launchers had been shut down, Ariane was, for a while, the only launcher available to serve the commercial market.

The Ariane order book literally took off. The launch rate doubled, from three to four flights per year carrying five to six satellites, to six to eight flights with 10 and 12 passengers. This success led to the first genuine scale-up of Ariane production. An order for 50 Ariane 4 launchers (batch P9) was confirmed in February 1989, to cater for launch rates of between 10 and 12 flights per year over the period 1995–2000. When Ariane 4, by then too costly for the market, was withdrawn from service in 2003, its performance had risen to almost five tonnes to GTO, and the P9 production batch covered a total of 95 launchers.


From a launcher designed for Hermes to a new commercial launcher

Back in 1978, CNES plans also included an ultimate version of the original Ariane concept, involving the existing Ariane 4 first stage capped by a cryogenic upper stage of 40–55 tonnes powered by an HM-60 engine. This precursor version of Ariane 5, bearing a strong resemblance to a ‘pumped-up’ version of the Europa 3 concept, would have had the task of placing up to 10 tonnes into low Earth orbit, and could therefore have carried the Hermes space plane. The concept was abandoned in the early 1980s in favour of an entirely new launcher architecture. The upper stage was tripled in size and became the main cryogenic stage, initially powered by the HM-100 and later the Vulcain engine, flanked by two solid propellant boosters six times larger than the Ariane 4 solid boosters, and with a bi-liquid upper stage for the orbit injection phase. Dimensioning of this Ariane 5 was revised a number of times as the estimated mass of Hermes increased from 15 to 20 tonnes.

The Ariane 5 design was adopted by ESA in 1987, with a configuration providing for a payload mass of 6.5 tonnes to GTO. Production of this giant called for new, suitably adapted industrial infrastructures, including the SuperSIL (launcher integration site) in Les Mureaux, and the UPG (Guiana propellant plant) in Kourou.

Regarded at the time as too powerful – its performance having been dictated by the Hermes space plane project, abandoned in 1992 – Ariane 5 was to prove entirely suitable for the market which it would have served from 1995/1996 if problems encountered during the qualification phase had not put back its commercial introduction to 1999. By that time, Ariane 5 could easily carry two three-tonne satellites, but market demand had risen to mass values of between 3.7 and four tonnes, and satellites of 4.5 to five tonnes were already on the way. At the Ministerial Conference of 1995 in Toulouse, the development of a cryogenic upper stage was postponed, as Germany was in the throes of absorbing the cost of its reunification. The design and production of two new stages was decided upon in Brussels in 1999. The ESC-A version, powered by an Ariane 4 HM-7 engine, was put into production immediately to raise transfer orbit capacity to 10 tonnes. The ESC-B version, requiring a longer development phase, would have a reignitable Vinci engine and a payload capacity of 12 tonnes.

The age of maturity

With a crisis-affected launch market, and in the face of extremely aggressive competition, the hunt for manufacturing cost reductions was in full cry. Negotiations for the second Ariane 5 production batch, which included the initial ECA launchers, were proving a very hard task. Efficient configuration management was a real headache. What with the different types of fairing, SYLDA, booster segments and adaptors, there are over 600 possible combinations. A victim of its own success, for which all parties have claimed their share, the Ariane programme had really become a many-headed hydra. Between ESA (acting as employer for the 12 member states), CNES (development prime contractor and design authority), Arianespace (operator and production prime contractor), Airbus Defence and Space (industrial architect) and the galaxy of first- and second-tier subcontractors (including numerous Airbus Defence and Space entities), streamlining of the situation was essential if Ariane 5 was to avoid meeting the same fate that Europa had 30 years earlier.

The failure of the first Ariane 5 ECA flight on 11 December 2002, which forcibly highlighted the limits of the existing programme management organisation, led to a complete rethink. The consolidation of responsibilities was agreed in a matter of months, and ratified at the Ministerial Conference of May 2003 in Paris. Airbus Defence and Space then became industrial prime contractor for the Ariane system, for both production and development. This new task-sharing arrangement took effect as of the PA production batch for which the order was placed in May 2004. The first of the 30 PA-batch launchers (L527) lifted off in March 2006.

“This was a real revolution,” recalls Pierre Verzat, Head of the Airbus Defence and Space Competence Centre until July 2009. While this transfer of responsibilities had been awaited for some considerable time, it came at the worst possible moment: “Such a transfer of responsibilities could only work if we were able to get Ariane 5 ECA back into operational service at the same time. This we managed to do.”

The new programme management structure bore fruit, as Michel Freuchet, Head of Airbus Defence and Space’s Launchers Business Division, describes: “We got rid of a tired and inefficient organisation, replacing it with genuine industrialisation of the launcher, and we moved on from a launch rate of three per year with launchers still behind schedule, to a rate of seven flights with launchers always ready on time.” Pierre Verzat adds: “We achieved this under difficult contractual conditions, conditions which only allowed us a minimum margin. For the current PB batch, we will work better and more efficiently still.”

With this new production batch, Ariane 5 must achieve a balanced financial position without support from the EGAS (European Guaranteed Access to Space) operational subsidy programme, as this programme terminates in 2010. “Provided the member states continue to cover the cost of maintaining the infrastructures in operational condition,” emphasises Michel Freuchet. “Whatever anyone says, Ariane 5 is not a commercial system any more than any other launcher in the world, but commercial activity means that we can maintain a system of strategic importance for Europe in operational service.”

At the same time, experience acquired with the launcher will make it possible to obtain a further payload capacity increase of 400kg between now and 2011, merely by optimising margins.

The next Ariane

The next challenge to be met is development of the Ariane 5 ME (Midlife Evolution) version, for which the design phase was decided on at the Ministerial Conference in The Hague in November 2008. For the first time it is industry – Airbus Defence and Space – that is responsible for Ariane development project management.

“Ariane 5 ECA was initially intended to serve as an interim launcher. It has not been optimised and a number of items, in particular in regard to the HM-7 engine, will induce problems of obsolescence,” notes Michel Freuchet.

Externally, Ariane 5 ME will look very like the Ariane 5 ECB as imagined 10 years back, but will have the benefit of technological advances made during the last decade, in particular with regard to electronics and some of the materials used. The Vinci engine, which was no more than a concept in 1999, has now reached the test-bed stage.

To prepare for Ariane 5 ME, Airbus Defence and Space will also have the backing of new development methodologies and technologies, involving the use of ‘virtual platforms’ where the engineers will be able to work concurrently on digital models without leaving their desks. “Germany will invest to a greater extent in this version, and it will consequently be necessary to restore the balance between industrial activities,” explains Pierre Verzat. “We have a year to set up this new arrangement.”

“Our aim is not to develop and fly a new prototype, but rather to develop an operational launcher substantially more rugged in terms of production than Ariane 5 ECA, accompanied by reduced costs and enhanced quality performance,” concludes Michel Freuchet.

LRBA: Laboratoire de recherches balistiques et aérodynamiques – Ballistics and Aerodynamics Research Laboratory.

** SEP: Société Européenne de Propulsion.

Launcher SystemArianeAriane 5