Soyuz ST Launch Vehicle
The Soyuz-ST is a modification of the three-stage Soyuz-2 rocket with a Fregat upper stage adapted for launch in high heat and humidity prevalent in Kourou. Despite its external similarities with the older spacecraft, the Soyuz-2 is an entirely new launch vehicle. Its cargo capacity was increased by 700kg. The first rockets are able to put over 8 metric tons into a near-earth orbit, and in the future when the third stage of the rocket is equipped with new engines manufactured at the Voronezh factory, the cargo capacity will be increased by another 500kg. Apart from its high technical performance, the new launcher differs from its predecessors in that all the components of the new rocket are manufactured in Russia.
The increased cargo capacity is only one of the Soyuz-2's improvements. It is also very important that the launch vehicle is equipped with an entirely new advanced digital control system which would allow the launch vehicle to place space vehicles in more precise stationary orbits. This, in turn, is vital for the successful mission of the cargo - a satellite.
The new control system enables the length of the launch vehicle's nose to be increased from 7.7 meters to 11.4 meters and its diameter to be increased from 3.7 to 4.1 meters. This means that the size of the cargo can also be increased considerably (orbiting 1kg of cargo costs about $30,000 on the world market).
The modernized version of Soyuz features the following major upgrades:
- A Digital control system with a digital computer and inertial measurement unit (IMU) based on proven technology, giving the Soyuz improved navigation accuracy and control capability. The digital control system is located primarily in the equipment bay of the third stage and was flight-qualified during the inaugural flight of a Soyuz 2-1a launch vehicle performed on November 8, 2004 from the Plessetsk Cosmodrome. The introduction of the digital control system leads to the following advantages: A more flexible and more efficient attitude control system (ACS) capable of handling the increased aerodynamic instability generated by the larger ST fairing; Increased accuracy in the flight of the first three stages of the Soyuz; The ability to perform in-flight roll maneuvers as well as in-plane yaw steering (dog-leg) maneuvers.
- The ST-type fairing with an external diameter of 4.110 m and a length of 11.400 m. The ST fairing enables the Soyuz to accommodate standard medium-class GTO telecommunications spacecraft in a dedicated configuration and to carry smaller payloads in a multiple-manifest configuration for LEO, MEO, SSO and escape missions. The ST fairing was flight-qualified on October 19, 2006.
- The RD-0124 engine is a staged combustion engine powered by a multi-stage turbopump spun by gas from combustion of the main propellants in a gas generator. These oxygen-rich combustion gases are recovered to feed the four main combustion chambers where kerosene, coming from the regenerative cooling circuit, is injected. Attitude control is provided by main engine activation along one axis in two planes. LOX and kerosene tanks are pressurized by the heating and evaporation of helium coming from storage vessels located in the LOX tank. The RD-0124 engine adds an additional 34 seconds of Isp, significantly increasing the overall launch vehicle performance.
A smaller number of people are needed for the new vehicle's pre-launch preparations. Currently, it takes 70 people to complete the Soyuz's pre-launch preparations, while only 15-20 people are needed to service the Soyuz-2. Only two people are required to service the new control system, as compared to the 40 people that are required for the previous Soyuz.
The Lavochkin Aerospace Association in Moscow, one of Progress' partners, has developed the Fregat booster unit for the Soyuz-2. The booster will help place spacecraft in near-earth orbits as well as put them on trajectories to other planets.
Europe did not have a medium-class launch vehicle like the Soyuz. Since Kourou is closer to the Equator than Baikonur, the cargo capacity of Russian spacecraft launched from Kourou will triple from 1.5 metric tons to 4 metric tons. It would be widely used by the European Space Agency for launching probes and spaceships from the European spaceport facility in Kourou in French Guiana. Kourou's position close to the Equator makes for the maximum possible harnessing of the natural rotation of the Earth for the purposes of space launches.
Construction of infrastructure for launches of Souyz spacecraft from the Kourou space center in French Guiana start in December 2005 and was expected to be completed in July 2008. The contract on the approximately 135-million euros project was signed on April 11, 2005 by CNES Director of Launchers Michel Eymard and Pierre Berger, the chairman of Vinci Construction Grands Projets, which represents the especially established industrial group Soyuz-Infrastructure. The program of cooperation between the European Space Agency and the Russian Space Agency envisages launches of Russian Soyuz-ST space carriers from the Kourou space center and the work on the construction of the three-stage carrier, Soyuz-2-1B. The first launch of Soyuz spacecraft from the French space center was initially planned for the second half of 2008.
On 30 September 2013, Russia orbited four 03b Networks satellites to provide broadband Internet access in remote areas, and on November 20 will send up the Gaia telescope for the European Space Agency. The O3b Networks satellites are designed and built by Thales Alenia Space to become a part of the first medium-Earth-orbit satellite constellation providing broadband Internet access in remote areas of the world.
In 2014, Soyuz-ST rockets were to orbit a Galileo navigation satellite, new O3b clusters and a Sentinel satellite as part of the ESA’s Global Monitoring for Environment and Security program. There are no plans to increase the number of launches from Kourou.
An evolution of the currently operational Soyuz, the new version of the launch vehicle meets the market's needs for a versatile, flexible vehicle capable of performing a wide range of commercial missions. With its successful inaugural flight on December 27, 2006 from the Baikonur Cosmodrome, the evolved Soyuz marks the latest step in a cooperative European/Russian evolution program and became a centerpiece of the European launcher fleet flying from French Guiana starting in 2011. A Soyuz launcher took off from Europe’s Spaceport in French Guiana on 21 October 2011. This was a historic event because it was the first time that a Soyuz was launched from a spaceport other than Baikonur or Plesetsk. It also marked a milestone in the strategic cooperation between Europe and Russia on launchers.
The evolution began with Starsem in 1999 and the addition of the restartable Ikar upper stage to the three-stage Soyuz, which then launched 24 satellites of the Globalstar constellation in six flights. Following this success, Starsem introduced the flexible, restartable Fregat upper stage from NPO Lavochkin with significantly more propellant capacity than the Ikar.
The decision of the ESA member states to introduce the new modernized Soyuz to the European Space Port in French Guiana (CSG) is a major step in widening the range of accessible missions for the Soyuz. Following the construction of a new Soyuz launch pad coordinated between the European, French and Russian Space Agencies, the launch vehicle's inaugural flight from the European Space Port was scheduled for 2011. With the introduction of the Soyuz to CSG, this famed Russian launch vehicle became an integral part of the European launcher fleet, together with the heavy-lift Ariane 5 and the lightweight Vega. To be offered exclusively by Arianespace to the commercial market, the Soyuz from CSG is Europe's reference medium-class launch vehicle for governmental and commercial missions.
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