Figure 1. Layout of facilities at the Guiana Space Centre, Europe's Spaceport
Once ESA had decided in 1987 to develop Ariane-5, Europe's new generation of heavy-lift launcher, it became clear that the facilities at the Guiana Space Centre had to be adapted to the new missions, in addition to building a new launch complex *. The 'CSG 2000 Programme', funded jointly by ESA and CNES, was instituted in 1991 to enable Ariane-4 and Ariane-5 launches to be supported with increased reliability and at reduced cost until at least 2015. It involves a thorough modernisation of all major systems at the Spaceport. The development efforts and equipment installation are being managed by CNES and performed by contractors from the ESA Member States, including local suppliers in French Guiana. The overall investment, in excess of 130 million ECU, covers the period from 1991 to 1998, but most of the new systems will be operational for the first Ariane-5 launch at the end of 1995.
* The production, assembly and launch facilities for Ariane-5 were described in ESA Bulletins Nos. 75 and 79.
The French Government committed itself to the construction of a launch base in its overseas department of Guiana in 1964. The land around the coastal town of Kourou was assigned to CNES, which built the first facilities. In 1966, the European Launcher Development Organisation (ELDO), one of ESA's forebears, decided to build its own launch facilities at CSG (Centre Spatial Guyanais). Following the 1973 decision to start the Ariane launcher programme, ESA committed itself to contribute substantially to the investment and operating costs of what was to become Europe's Spaceport .
About 1300 permanent employees now work at CSG, more than half of them locally recruited, the other half being specialists drawn from metropolitan France and other ESA Member States.
There are two distinct sets of facilities at CSG (Fig. 1), each falling within a specific management framework: those dedicated to launcher production and launch and to spacecraft preparation, and the general spaceport and range facilities:
Facilities for launcher production and launching and for spacecraft preparation
These have been built and
are owned by ESA, which entrusts their operation to external entities. About 400 people are employed
in this set of facilities, which include:
Range facilities
These support functions are mainly located at the 'Technical Centre' and associated
facilities and tracking stations. An Agreement between the French Government and ESA defines the
management rules applicable at CSG, as well as the financing scheme for the investment and operating
costs. The ESA-financed part represents two-thirds of the total annual budget of about 110 million ECU.
The remaining third is covered by CNES, which also manages everyday activities at the Spaceport with
the support of several industrial contractors (a total of 900 employees).
The CSG 2000 Programme described here is part of the Spaceport's annual investment plan.
Figure 1. Layout of facilities at the Guiana Space Centre, Europe's Spaceport
The CSG 2000 Programme, begun in 1991, is designed to guarantee successful fulfilment of the Spaceport's main missions through 2015, namely:
Protection of persons, property and the environment
One of the Spaceport's main roles is to perform the
tasks involved in assuming 'launching State' liability, under the 1972 Convention on International Liability
for Damage Caused by Space Objects. This includes the protection of persons, facilities and the
environment both during ground operations ('ground safety') and during launches ('in-flight safety').
High-quality launch-service support
This support includes:
Figure 2. Kourou's geographical situation allows launches over a wide azimuth range. A network of down-range stations is used to acquire uninterrupted launcher telemetry
Safety during ground operations Before a new type of hazardous operation is authorised, such as filling a new type of spacecraft, launching into a new trajectory or performing a static firing test, a detailed 'safety submission' process is undertaken by the CSG safety engineers.
When potentially hazardous operations are to be carried out, a strict set of constraints laid down in legislation and in CSG's Internal Safety Rules have to complied with, i.e. maximum number of operators on site, minimum safety distances for all other personnel, verification procedures to be followed before, during and after the operation, etc.
Hazardous operations may be carried out at different CSG sites at the same time, i.e. road transport of propellant, spacecraft or launcher filling, solid-propellant mixing and casting, or booster assembly. Safety engineers are posted at different sites to monitor such operations and to advise the site managers in a decentralised scheme, but centralised safety coordination is needed to ensure that operations running in parallel are compatible, and to coordinate actions in the event of an accident.
The CSG 2000 Ground Safety Coordination (CSS) project includes the development and installation of a control and command building for the safety coordination team, and new control rooms for the fire brigade. This CSS building, located at the Technical Centre, is linked by voice, video and data lines to all sites where hazardous operations are conducted, as well as with the other Spaceport systems. The sophisticated tools available in the event a mishap include a computer system capable of simulating the evolution of a leakage cloud under the prevailing conditions and superimposing it on the site map.
The installation of CSS equipment and the first tests were completed at the end of 1994, and training in the operation of the new systems has been in progress since early 1995.
In-flight safety
Before each mission, the Flight Safety Team must approve the trajectory being proposed
by the launch operator. For this task, known as 'safety submission', powerful computing and simulation
tools are employed.
From lift-off onwards, the Flight Safety Team needs real-time information on the launcher's behaviour and flight path in order to evaluate any potential danger to populated areas. The launcher itself also needs protection from spurious commands. A flight-termination system is available to remotely command destruction of the vehicle in flight. The launcher itself can also generate a termination command if its on-board computer should detect a structural failure or abnormal stage separation (Fig. 3).
Real-time computer processing of tracking-radar and telemetry data allows the Flight Safety Officer to monitor a display of the launcher's predicted impact point in the event of an abnormal interruption in propulsion. The CSG 2000 development programme has included new safety software that computes the impact zone of the debris shower in the event of an in-flight explosion, taking into account the effects of winds and atmospheric drag.
New equipment with high reliability, redundancy and built-in self-check devices was installed for Ariane-4 launches in 1991; the Ariane-5-specific equipment is being installed and tested during the first half of 1995.
Figure 3. Protection of populated areas in the event of abnormal launcher performance requires a complex but reliable vehicle-destruct system
Tracking the launcher
Until 1987, Ariane
tracking relied exclusively on 'external' sensors, i.e. tracking radars on the ground, along the launcher's
trajectory. The only tracking information provided by the launcher itself was an amplified signal sent back
to the ground radars by its on-board radar transponders.
As the on-board inertial guidance has proved to have sufficient accuracy and reliability, this 'internal' tracking sensor has increasingly been used for a number of functions:
The CSG 2000 Tracking and Plotting upgrade project (SLT), started in 1991, involves:
Figure 4. The Ariane-4 telemetry acquisition and processing system for eastward launches DT =digital designation of target CVI =quick-look telemetry display
The down-range telemetry stations
For both Ariane-4 and Ariane-5 launches, for eastward (Geostationary
Transfer Orbit) and northward (Sun-Synchronous Orbit or Low Earth Orbit) trajectories (Fig. 2), the full
vehicle trajectory until the end of its mission* has to be covered, seamlessly, by down-range stations that
receive, record and dispatch the telemetry data to the processing centres. Telemetry stations all along
the trajectory's footprint are used for this purpose: in French Guiana, a Cassegrain-type antenna is
located on the Montagne des P res, a hill some 25 km southeast of the launch pads (Fig. 1). A nearby
antenna belonging to the CNES satellite control network is used as a back-up on launch days.
For eastward launches (Fig. 5), which are the most common (more than 80% of all Ariane launches are to GTO), the network is as follows:
Northward launches from Kourou are far less frequent, and agreements between ESA, NASA and the Canadian Space Agency are set up on a case-by-case basis for using the US Bermuda station and the Canadian Prince Albert station. A mobile station will also be used in northern French Guiana to overcome signal masking by the plumes of Ariane-5's solid-rocket boosters.
* With payloads correctly injected into orbit and upper stage 'passive' with its fuel tanks empty to avoid possible explosion and generation of unnecessary debris.
Figure 5. Typical Ariane-4 eastward-mission profile
Figure 6. The Natal station in Brazil (photos courtesy Concorde Europe Films)
Figure 7. The Ascension Island (UK) station in the South Atlantic (photos courtesy of Concorde Europe Films)
Figure 8. The Libreville station in Gabon, West Africa (photos courtesy of Concorde Europe Films)
This project (SYSTA) is gradually providing an increase in the reliability of all down-range stations. To avoid the cost of installing two redundant antennas at each station, a thorough upgrading of the mechanical and electrical antenna drive systems is being carried out.
The tracking performance of the telemetry antennas is also being increased. The launcher transmits its telemetry signals in two circular-polarisation modes; until recently, only one of these could be received at a time, with the risk of receiving the weaker signal and possibly losing the link. A new reception system has been developed that automatically chooses the polarisation providing the best signal. Also, a velocity memory feature has been introduced, allowing continuation of antenna movement (rather than an antenna stop) in the event of signal loss. For Ariane-5, a new telemetry standard recommended by the International Consultative Committee for Space Data Systems (CCSDS), with a grid-structured signal and a Reed-Salomon-type coding, is being introduced. This new standard simplifies signal processing on the ground and improves the launcher-to-ground link quality (transmission rate 1 Mbit/s).
The storage capacity at the stations is also being enlarged and their telemetry transmission rates are being increased. In addition, remote monitoring tools are being developed to improve the reliability of station operation during countdown. The latter is the only SYSTA subsystem not yet implemented, but it will be operational in 1996.
With the crucial involvement of so many scattered sites, CSG operations require careful planning and coordination. The CNES/CSG Operations Division includes a team of Operations Directors (called DDOs, from the French Directeurs d Op rations), each being assigned one launch and one team of assistants well in advance. The DDO's responsibility is twofold:
The CSG 2000 Programme has provided a new computerised operations planning tool (PLO) which uses a large database of standard 'operations sheets' to simplify the work of the operations and site managers, as well as safety, quality and cost control. This new tool was installed in 1994 and is being validated during the first half of 1995.
The new multi-mission range Control Centre (CDC, Fig. 9) is being built in the new Jupiter 2 building. Information from the specialised, remotely located control rooms (launcher control room, tracking and telemetry stations, etc.) converges on the CDC, from which final launch authorisation is given. The new CDC has been designed to handle Ariane-4 as well as Ariane-5 launches.
Figure 9. Mockup of the interior of the new Jupiter 2 building. From front to back: the cabins for the Press, the VIP
Room seating 250 and, behind the glass partition, the main Mission Control Room (CDC)
The telecommunication networks have been completely upgraded with the installation of an extensive fibre-optic network linking all CSG sites. The synchronisation system drives equipment that requires precise and synchronised timing, including launcher checkout systems, tracking and telemetry networks, flight safety systems, etc.
The supply and distribution of air conditioning and back-up power is also being upgraded with more powerful and more reliable equipment. Lightning protection for sensitive areas is also being upgraded.
CSG's Weather Station provides a fully fledged meteorology service (forecasting, monitoring and a statistical archive) for operations purposes. The CSG 2000 Programme is providing state-of-the-art equipment for both local measurements of temperature, electrical fields and wind speed (including wind shear at altitude), and larger-scale observations with weather radar, satellite imagery and meteorological charts.
The public-relations facilities at CSG are also being substantially upgraded in time for the first Ariane- 5 launch at the end of the year. They will include a new Space Museum, with a full-scale mock-up of Ariane-5, next to the Technical Centre, and several observation sites close to the launch pads (Fig. 9, Fig. 10). There will also be a new VIP room (seating 250), and a new Press Centre in the Jupiter 2 building.
Figure 10. Construction of the Space Museum Jupiter 2 complex under way in October 1994. The launch facilities, 14
km away, can be seen at the top of the picture
Figure 11. The infrastructure of the Jupiter 2 building was completed early in 1995. Installation of the exhibit material in the Space Museum is progressing
Figure 12. The Guiana Space Centre, ready to serve Ariane and its customers for the next twenty years
The CSG 2000 Programme, when completed, will enable the Guiana Space Centre, Europe's Spaceport, to maintain its reputation as one of the best launch bases in the world. The regular upgrading of the equipment and training of personnel will ensure optimum performance for many years to come.
The authors wish to express their thanks to Mr Philippe Noël, Deputy Director of Operations at CNES/CSG, for his valuable contributions to this article.
ESA Bulletin Nr. 83.