Esa Bulletin November 1997 [antikvár]

The Ariane-502 Success: A Demonstration of Europe's CommitmentThe 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.As just reward for 16 months of intense effort by the ESA and CNES Teams, the second Ariane qualification flight, V502, took place on 30 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 also 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 was 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 did not adversely affect the execution of the payload's experiments.Commenting in Kourou on the results of this second qualification flight of Ariane-5, Antonio Rodota, 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 dol All of us who have consistently believed in Ariane have today witnessed the start of a new success story "First indications are that the Teamsat (Technology, science and Education experiments Added to Maqsat) payload has functioned well. Its five experiments were proposed and delivered for integration in record time just 7 months by a number of European Universities working under the coordination of ESTEC's Automation and Informatics Department. The spacecraft itself was built using spare parts from other satellites, and technicians and engineers at ESTEC devoted many hours to helping the youngsters in its realisation. The unique picture shown here was taken by Teamsat's Visual Telemetry System (VTS) of three cameras designed to acquire images of critical operations. It shows the Ariane-5 Speltra/upper-stage composite lagging behind 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.The successful achievement of this major milestone in the Ariane-5 development programme is the result of the dedication and hard work of the 6500 people who have been involved in various capacities in the development of Europe's new launcher over the past ten years!Lesa5