ESA has shown and continues to show that, despite their differing perceptions and interests, scientists, engineers, industry and governments can overcome national and institutional barriers in the pursuit of a common goal. ESA, in fact, is intended to be not merely an agency dedicated to space, but also an organisation that combines technology and industrial policy at the European level.
Over the last 30 years, Europe has managed to develop a strong capability in all sectors of space activity, and to keep pace with the high-technology developments that the space era has brought in all areas, ranging from space science to space transportation. Cooperation in space research, achieved by combining European scientific and technological potential, is one of Europe's most visible and truly great achievements.
The Ariane family of launchers, which gives Europe autonomous access to space at an affordable cost, is an outstanding example of European success achieved through collaboration.
The Ariane family has stead fly evolved over time, with mission objectives and the performance of the launchers continuously being modified to meet commercial needs and remain competitive. In turn, the production and launch facilities have also had to be regularly upgraded.
In November 1987, the Ministers of ESA's Member States agreed to finance the Ariane-5 development programme, thereby giving Europe the means to develop the launcher it needs for the next century. As part of that programme, all facets of production have had to be redefined.
The industrial facilities to produce, test and integrate the launcher elements had to be set up very early in the development phase, to be ready for the production of the first ground test and flight demonstration models, and for system validation.
More than 100 companies and 6000 people from 12 European countries have been involved in the development. The industrial organisation established was based on European industry's experience gained through the development of the earlier launchers, Ariane-1 to Ariane-4, and on the principles of ESA's industrial policy. ESA delegated the technical and financial management of the programme to CNES, the French space agency. After completion of three qualification flights, the operation and exploitation of the launch system will be entrusted to Arianespace. As it currently is for Ariane-4, that company will also be responsible for managing and financing the production of Ariane-5 vehicles, marketing launch services world-wide and carrying out launch operations at the Guiana Space Centre in Kourou, French Guiana.
In addition, many launcher elements have to be shipped from Europe to the launch site in Kourou. New containers have been developed to transport elements that are very large or require safe handling from the production facilities, across Europe and the Atlantic Ocean to the recently-upgraded harbour in Kourou. They are moved by road, rail, river or sea to major European harbours, loaded onto seagoing vessels and shipped across the ocean (Fig. 1).
Figure 1. Launcher elements are transported by road, rail, river and sea from their production site to a major European port and then by ship to Kourou. The inset shows a main-stage transport trailer being rolled off from the transatlantic vessel in Kourou harbour
The design of the production facilities was greatly influenced by both the criteria imposed on the development of the launcher and the production design principles adopted.
To minimise risk, several criteria have been applied to the development of the Ariane-5 launcher and the associated ground facilities. They are:
Given the planned production rate of at least eight launchers per year for the next 15 years, several technical and industrial choices had to be made to ensure the following:
The basic approach taken was to produce the Ariane elements in Europe and to integrate them at the Guiana Space Centre for safety reasons, the booster propellant plant (UPG), the booster integration building (BIP), and the booster test stand (BEAP) were built in French Guiana).
Approximately 30% of Ariane-5 facilities were built in Europe and 70% in French Guiana. Approximately one billion ECU (European Currency Units) have been invested in the ground facilities, representing 20% of the total cost of the Ariane-5 development programme.
Only the Ariane-5 facilities involving major dedicated ESA and/or industry investment are considered here.
The EAP is composed of four main subsystems (Fig. 2): the solid propellant motor; the forward skirt; the aft skirt, which supports the whole launcher on the launch platform until lift-off; and the nozzle control system*. Together, the two EAPs provide 90% of the launcher's thrust at lift-off, transmitting it to the core stage via the forward attachment device on the front skirt.
* The EAP manufacturing, integration and test facilities in Kourou were described in ESA Bulletin No. 75 (August 1 993).
Figure 2. The solid propellant stage (EAP) and its components. The photograph shows a fully integrated solid booster leaving the Booster Integration Building at the Guiana Space Centre
Some Ariane-5 launchers will also carry a special 'recovery kit' with parachutes located inside the front skirts of the EAR These parachutes will be used to recover the boosters from the sea, after a launch. The boosters will then be analysed at the Guiana Space Centre, and some components will be returned to Europe.
The main propulsion stage is made up of five main components: the front segment S1, the central segment S2, the aft segment S3, the nozzle, and the igniter.
The industrial cycle starts at the MAN-Technologie plant in Augsburg (Germany) with the manufacture and proof-testing of the metal cases of the segments. The S2 and S3 segments are each made up of three cylinders, assembled in Augsburg with 'factory joints' of the clevis-tang type. The S1 segment consists of only one cylinder.
These activities are carried out in two buildings: the case production building and the proof-test building. The most important item of equipment is a counter-roller flow-turning machine. Weighing 500 t, it cold-forms cylinders from a blank of special steel, reducing their wall thickness from 40 mm to 8 mm and increasing their length from approximately 1 m to 3.5 m. A precise heat tempering/quenching treatment then gives these thin-walled sections a breaking strength of 1500 N/mm2.
A booster consists of seven such sections plus a front dome and an aft dome, which are later joined in a shear pin connection, yielding an overall length of 25 m. The clevis-tang joints withstand a traction force of 50 000 kN during the ignition phase of a launch, and must meet tolerance ranges calibrated in hundredths of a millimetre.
The booster metal cases are shipped from Augsburg (Germany) to Colleferro, near Rome (Italy), where the internal thermal insulation is installed at the dedicated Fiat Avio plant. The insulation is made of rubber (silica and kevlar-filled EPDM) produced by SNECMA/SEP in Bordeaux (France). The metal case degreasing system, the blasting system, the rubber application system, and the autoclave for vulcanisation of the rubber insulation are the main elements of the thermal protection plant.
The thermally-protected front segment S1 is then sent to the propellant plant, also located in Colleferro-Rome, for casting operations. The insulated central and aft segments are shipped directly to the Guiana Propellant Plant (UPG) in Kourou for casting.
The nozzle is manufactured at a dedicated SNECMA/SEP plant in Bordeaux (France) and shipped to Kourou for integration with the EAP. The igniter is cast and assembled at the Fiat Avio plant, and then shipped to Kourou for integration with the EAP.
The forward and aft skirts are manufactured by SABCA near Brussels (Belgium).
The EPC is composed of five subsystems (Fig. 3): the Vulcain engine and its actuation system, the main tank, the thrust frame, and the forward skirt.
Figure 3. The cryogenic main stage (EPC) and its main components. The photograph shows a fully integrated main stage being brought to vertical position at the Launcher Assembly Building in Kourou
Vulcain engine
The Vulcain engine is made up of four main components: the hydrogen turbopump, the oxygen turbopump, the combustion chamber and the nozzle. The hydrogen turbopump is manufactured by SEP in Vernon (France), the oxygen turbopump by Fiat Avio in Turin (Italy), the combustion chamber by Daimler Benz Aerospace (DASA) in Ottobrunn (Germany), and the nozzle by Volvo Aero Corporation in Trollhättan (Sweden).
The engine is assembled in the SNECMA/SEP cryogenic motor assembly building in Vernon. Firing tests to support the development of the Vulcain engine started in 1990 on two identical, specially-built test stands, the PF50 stand at SEP in Vernon and the P5 stand at DLR in Lampoldshausen (Germany).
Main tank
The main tanks is made of aluminium composite and is divided into two volumes by a common bulkhead. It contains 130 t of liquid oxygen at -180°C and 25 t of liquid hydrogen at -250°C. The metal case is made up of three bulkheads and seven cylinders.
The main tank production cycle starts at DASA/Dornier in Oberpfaffenhofen (Germany) with the manufacture of three tank bulkheads: the forward bulkhead (oxygen tank), the aft bulkhead (hydrogen tank) and the common bulkhead. Each bulkhead is made up of eight sectors and a Y-ring which provides an interface between the bulkhead and the other EPC components. The most sophisticated pieces of equipment in the facilities are the three welding machines.
The seven cylinders, each one comprising three pre-formed and welded panel are manufactured at the Cryospace plant in Les Mureaux (France). The cylinders and the bulkheads are then welded together, pressure-tested, insulated, equipped, and finally delivered to Aerospace's plant on the same site, for assembling into the EPC stage.
Forward skirt
The forward skirt is made of aluminium and fibre composites. It transmits the thrust generated by the boosters through two fittings to the launcher's central body. These fittings also contain the booster forward jettison mechanisms.
The forward skirt structure is manufactured at MAN-Technologie in Augsburg (Germany). It is then delivered to Aerospatiale in Les Mureaux, where measurement, control, telemetry and pyrotechnic items are installed.
Thrust frame
The thrust frame is assembled at Fokker's Special Products plant in Hoogeveen (The Netherlands) and then shipped to Aerospatiale in Les Mureaux.
The engine thrust actuation unit, the hydraulic system that activates the thrust vector control of the Vulcain engine, was developed and is manufactured at SABCA near Brussels (Belgium).
EPC assembly
All EPC elements and related electrical systems are assembled and then tested using a specific checkout installation in the Aerospatiale assembly building on the banks of the Seine in Les Mureaux. The checkout equipment used during the launcher integration campaign in Kourou is fully compatible with that in
Les Mureaux, enabling the same verifications to be run both in Europe and French Guiana.
Once completed, the EPC is placed in a special transport container and shipped to Kourou via the French port of Le Havre (Fig. 1).
Figure 4. Although the Vulcain engine is integrated into the main stage in Europe, the necessary tooling and procedures are in place in case an engine has to be replaced at the launch site
The Vehicle Equipment Bay (VEB) contains electrical and electronic equipment that performs launcher guidance and control during flight (Fig. 5). It consists of a mechanical structure, including the main structure made up of a cylindrical section and an internal cone, made of aluminium alloy and built by CASA in Madrid (Spain). Casa developed special cylinder and cone assembly tooling for this purpose. The structure is delivered to Matra Marconi Space in Toulouse (France) for integration of the electrical and electronic equipment. Those subsystems include:
Figure 5. The Vehicle Equipment Bay (VEB). The photograph shows a VEB being mated on top of the main stage in Kourou
Figure 6. The Functional Simulation Facility at Aerospatiale used to verify the flight-specific software for each launch (Photo courtesy of Gonin/Aerospatiale)
ETCA (Belgium) has developed a functional checkout system foe the VEB, as well as most of the software. Equivalent checkout systems are used at the integration site in Toulouse and the launcher assembly site in Kourou.
Once integrated, the VEB is taken by road to Les Mureaux, for onward ship transport to Le Havre and Kourou.
The EPS is composed of three major subsystems (Fig. 7): the Aestus engine, the mechanical structure and the propellant tanks. The stage was developed by DASA in Bremen (Germany), where stage integration is also performed during the production phase.
Figure 7. The storable propellant stage (EPS). The photograph shows a fully integrated EPS
The Aestus engine is manufactured by DASA in Ottobrunn (Germany). The engine development tests were carried out at the DLR test stands in Lampoldshausen (Germany).
The mechanical structure was designed as a truncated cone with an upper flange to interface with the VEB. It is manufactured at the CASA plant near Madrid (Spain) and transported to Bremen by road.
Each propellant tank consists of a cylindrical section and two hemispheres made of an aluminium composite. Special equipment has been set up at the Zeppelin plant in Friedrichshafen (Germany) for spin-forging of the cylinders, spin-forming of the hemispheres, heat treatment, and welding of the spheres onto the cylinders.
The assembly, integration and testing of the EPS is carried out on a test stand at the DASA facility in Bremen. This stand is composed of two EPS assembly jigs, and separate electric and pneumatic check-out units. The stand's design affords easy access for integration of stage elements and components since it can handle the hardware in vertical, roll and pitch positions.
The assembled EPS stage is shipped from Bremen to Kourou, via Rotterdam and Le Havre. In Le Havre, it is loaded with other Ariane elements onto a single, custom-built vessel.
External carrying structure for multiple payloads (SPELTRA)
The major structural components of the SPELTRA (Fig. 8) are the carbon-fibre reinforced panels in the cylindrical and conical parts, and the rings. DASA/Dornier in Friedrichschafen (Germany), which is responsible for the development of the SPELTRA, has set up special manufacturing and inspection equipment for the components, and an assembly stand (Fig. 10).
Figure 8. The SPELTRA and its components
Figure 10. The SPELTRA being assembled at Daimler Benz Aerospace in Germany
The complete SPELTRA is loaded in the harbour at Kehl on the Rhine and shipped to Kourou via Rotterdam and Le Havre.
Flight adaptors
These are the conical interfaces between launcher and spacecraft. They are made by CASA in Spain using an aluminium honeycomb core reinforced with carbon-fibre layers. Saab (Sweden) provides the clamp-bands for securing the spacecraft during launch, which are released pyrotechnically for spacecraft injection into orbit.
Fairing
The fairing (Fig. 9) is manufactured by Oerlikon Contraves in Zurich (Switzerland).
Figure 9. The fairings and their components
A vertical integration station in the integration building used for Ariane-4 at the Swiss Federal Aircraft Plant in Emmen has been upgraded for Ariane-5fairing integration (Fig.11).
Figure 11. Vertical integration of a fairing
Once completed, each half shell is placed in a custom-made container and transported to the harbour at Basle on the Rhine, and then shipped to Kourou via Rotterdam and Le Havre.
Flight data evaluation
To ensure that optimum launcher performance is maintained, flight data will be evaluated after each launch and, if any anomalies are detected, vehicles in production at that time will be modified.
Although a quick-look evaluation of launcher telemetry is done in real time, it covers only a small proportion of the data. A much more detailed analysis of hundreds of parameters relating to propulsion, guidance, and stage separations for example, is performed after each launch. They are recorded during flight at the Ariane downrange stations. Raw data are then sent, after the flight, through dedicated high-speed links to CNES in Toulouse, where they are decoded, precisely time-stamped and pre-validated.
From Toulouse, processed flight data are sent to CNES in Evry and to SEP in Vernon, where the various launcher manufacturers can log in and analyse the data, beginning as soon as four days after launch. Any flight anomalies identified must be fully understood and the production process modified accordingly.
At the current stage of the programme, the industrial facilities are well adapted to production of the new Ariane-5 launcher. One or two need to be upgraded to be compatible with the planned launch rate of eight or more vehicles per year for at least 15 years. Additional installations (buildings, machinery, tooling) are currently being developed, taking into account both the lessons learnt during the development of the launcher and the market expansion that is forecast by Arianespace, the launch operator.
An initial batch of 14 Ariane-5's was ordered by Arianespace from industry in 1995, and a second batch of 20 launchers is to be ordered in 1998 as part of a global commitment for 50 launchers. Once the three qualification flights (501 to 503) have been completed, operational
ESA Bulletin Nr. 93.