ESA AND SPACE TRANSPORT SYSTEMS

A sine qua non for an independent and ambitious space programme is the setting up of an independent launch system. This was realised from the early 1960s by the future Member States of ESA, and drawing on the experience gained with the earlier Europa programme the Agency was able in record time to decide on the Ariane programme and bring it to fruition, thus giving the Old Continent its own launcher. A remarkably clear-sighted management of this new system, and its rapid transfer to private operation, have yielded the success it enjoys today, and have given ESA the impetus to develop the Ariane-5 heavy-lift launcher and to study the space transport systems that will follow in the years to come.

Ariane -1 to 4

An Ariane-4 on the launch pad in Kourou Putting an ambitious space programme in place entails acquiring independent access to Space. The Europeans realised this from the outset, and their efforts took concrete form in July 1973 in Brussels, with the adoption of the Ariane programme by the countries who subsequently formed the European Space Agency.

Based on proven technologies and a European know-how gained in the various national programmes, the Ariane programme has given ESA a reliable launcher of its own, and thus its own means of access to space.

The European Ariane rocket, which first flew on 24 December 1979, has become a commercial launcher, taking bookings from many countries for launching their satellites.

It was designed from the start specially for putting satellites, e.g. for telecommunications and meteorology, into geostationary transfer orbit, and has brought down the cost by regularly launching two at a time.

Arianespace, the international company that markets the Ariane launchers, today holds more than half of the launch market, with customers in Europe, the US, Japan, Canada, India, Brazil and elsewhere around the world.

As the mass of satellites was getting ever larger, Ariane-1 gave way, from 1984, to the more powerful Ariane-2 and Ariane-3, and these were in turn superseded, when the Ariane-4s arrived in 1988. As Europe's "space workhorse", Ariane-4 is available in six versions one "bare", and the others fitted (depending on the mass to be put into orbit) with two or four, solid or liquid strap-on boosters.

With its eighty-fourth launch on 13 March 1996, Ariane had put a total of 153 satellites into orbit. Operating Ariane has allowed Europe to win fresh credibility in space affairs, and to introduce the idea of commercial space transportation.

Ariane - 5
The Ariane-502 Success: A Demonstration of Europe’s Commitment

Liftoff on October 30 1997 of the second Ariane 5 qualification flight from the Guiana Space Centre, Europe's Spaceport As just reward for 16 months of  intense effort by the ESA and CNES Teams, the second Ariane qualification flight, V502, took place successfully on 30 October.

The Launch Readiness Review for flight 502, held at the Guiana Space Centre, in Kourou, on 27 and 28 October had conducted a detailed analysis of the status of Europe’s new-generation Ariane 502 launcher, its payload and all of the ground facilities, including the launch-base and down-range stations that would track the flight, and had declared them ready for the launch. The Director Generals of ESA and CNES accordingly authorised the start of  the countdown for the 30 October lift-off, and the launcher itself was rolled out from the Final Assembly Building on the morning of  29 October.

Lift-off occurred  at 10h43 local time (01.43 p.m. GMT), 7 seconds after ignition of the main-stage Vulcain engine. Ariane-5’s two solid-propellant boosters powered the launcher during the first part of its flight, before their separation from the main stage. The fairing that protects the payloads during the ascent phase were jettisoned 3 minutes after lift-off.

27 minutes into the flight, the Maqsat-H and Maqsat-B platforms, carrying instruments to analyse the launcher’s flight behaviour, and the TeamSat technology satellite were injected into orbit.

A preliminary analysis of the Ariane 502 flight data immediately after launch confirmed that all propulsion systems - the two solid boosters, the main cryogenic stage and the storable-propellant stage - had functioned correctly, as too did  the launcher’s software, guidance, attitude control and electrical systems. A disturbance in the movement of the main cryogenic stage, the source of which is still under investigation, resulted in a lower than expected orbit for Teamsat, which fortunately has not adversely affected the execution of the payload’s experiments.

Commenting in Kourou on the success of this second qualification flight of Ariane-5, Antonio Rodotà, ESA’s Director General, voicing his first thoughts and those of all of the ESA and CNES staff who had worked so hard to achieve this goal after the intense disappointment of the first flight, said: “….This is another good example of what European cooperation can do!… All of us who have consistently believed in Ariane have today witnessed the start of a new success story…...

Teamsat
First indications are that the Teamsat (Technology, science and Education experiments Added to Maqsat) payload is functioning well. Its five experiments were proposed and delivered for integration in record time - just 7months- by a number of European Universities working under the coordination of ESTEC’s Automation and Informatics Department. The unique pictures shown here were taken by TeamSat’s Visual Telemetry System (VTS) of three cameras designed to acquire images of critical operations. The sequence  shows the Ariane-5 Speltra/upper-stage composite falling behind 19, 29 and 64 seconds after separation at an altitude of 600 km, with Africa in the background.

The third Ariane-5 qualification flight, under ESA and CNES responsibility, is scheduled for Spring 1998. Commercial Ariane-5 flights, which will be managed by Arianespace,  will then begin with the fourth launch, currently planned for the second half of 1998.

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