Soyuz launch vehicle

The Soyuz launch vehicle is an expendable launch system designed by the Soviet Union and used as the launcher for the manned Soyuz spacecraft. However it is a general purpose launch vehicle with other uses, including commercial launches marketed and operated by the Starsem[?] company. There were 11 Soyuz launches in 2001 and 9 in 2002. Soyuz vehicles are launched from the Baikonur Cosmodrome in Kazakhstan and the Plesetsk Cosmodrome in northwest Russia. They are manufactured in Samara, Russia.

The launcher was introduced in 1966, deriving from the Vostok launcher, which in turn was based on the R-7a intercontinental ballistic missile. It was initially a three-stage rocket with a Block I upper stage. Later a Molniya variant was produced by adding a fourth stage, allowing it to reach highly elliptical orbits. A later variant was the Soyuz U. The production of Soyuz launchers reached a peak of 60 per year in the early 1980s.

In the early 1990s plans were made for a redesigned Soyuz with a Fregat upper stage. The Fregat engine was developed by NPO Lavochkin[?] from the propulsion module of its Phobos interplanetary probes. Although endorsed by the Russian Space Agency[?] and the Russian Ministry of Defence[?] in 1993 and designated "Rus" as a Russification and modernisation of Soyuz, and later renamed Soyuz 2, a funding shortage prevented implementation of the plan. The creation of Starsem[?] in July 1996 provided new funding for the creation of a less ambitious variant, the Soyuz-Fregat or Soyuz U/Fregat. This consisted of a slightly modified Soyuz U combined with the Fregat upper stage, with a capacity of up to 1,350 kg to geostationary transfer orbit. In April 1997, Starsem obtained a contract from the European Space Agency to launch two pairs of Cluster 2 plasma science satellites using the Soyuz-Fregat. Before the introduction of this new model, Starsem launched 24 satellites of the Globalstar constellation in 6 launches with a restartable Ikar upper stage, between September 22, 1999 and November 22, 1999. After successful test flights of Soyuz-Fregat on February 9, 2000 and March 20, 2000, the Cluster 2 satellites were launched on July 16, 2000 and August 9, 2000. The only other planned Soyuz-Fregat launch is the ESA's Mars Express probe from Baikonur in June 2003. It is then due to be replaced by the new launcher, now named Soyuz/ST.

A long string of successful Soyuz launches was broken on October 15, 2002 when the unmanned Soyuz U launch of the Photon-M satellite from Plesetsk exploded 29 seconds after lift-off. One person was killed and eight injured.

The Soyuz is expected to experience increased use in 2003 to help mitigate the temporary suspension of the US space shuttle program. The Soyuz will be carrying supplies and exchanging crew in the International Space Station which the shuttle program would otherwise have provided. The US space shuttle program is expected to be suspended for at least a year for safety reviews in response to the Columbia space shuttle disaster.

External links

• Starsem (http://www.starsem.com)
• Soyuz launch log at Starsem (http://www.starsem.com/soyuz/log.htm)
• Soyuz U/Fregat (http://www.orbireport.com/Launchers/Soyuz_U-Fregat/)