CSTS

From Wikipedia, the free encyclopedia

This article or section may contain original research or unattributed claims. Please help Wikipedia by adding references. See the talk page for details.

For the trade union, see Confederation of Cameroon Trade Unions

CSTS or ACTS (Crew Space Transportation System and Advanced Crew Transportation System respectively) is a crew transportation system which is jointly studied by the European Space Agency (ESA) and the Russian Space Agency (Roskosmos) with the objective to design a spacecraft for LEO operations such as servicing the International Space Station but also capable of exploration of the Moon and beyond. This study was conceived as a basic strategic plan to keep a viable European human space program alive because NASA officials have announced that NASA's Vision for Space Exploration Orion spacecraft will be developed without participation of international partners. According to press releases and ESA official Manuel Valls, JAXA could join the cooperation as well.^[1] CSTS is currently in an initial study phase, which shall last for 18 months from September 2006 to spring 2008. The outcome of the study is planned to be presented to the ESA full member state conference in 2008.^[2]

Contents 1 Background 1.1 CSTS as answer to the Orion 1.2 Cooperation with Russia 1.3 Farnborough Air Show 2 Overall Design 2.1 Three module design[8] 2.2 The re-entry module 2.3 The habitation module 2.4 The service module 3 Missions beyond LEO 4 Launch Sites 5 See also 6 References 7 External links

[edit] Background

[edit] CSTS as answer to the Orion

In 2004 George W. Bush announced the Vision for Space Exploration, a program that includes the United States return to the Moon by 2020 and a manned mission to Mars by 2030.

For these purposes the Crew Exploration Vehicle, Orion, is currently being developed. ESA officials have inquired whether they could be part of this program for exploration,^[3] however received a negative response. Jean-Jacques Dordain, ESA's General Director stated with regard to this rejection by NASA: "I have been told by Mike Griffin and Marburger that the CEV is not for international cooperation. But if Europe is not involved in the next-generation transportation systems, we will stay forever a second-class partner."^[1] In this statement Griffin speaks of a general cooperation, not a cooperation in developing the Orion, the actual vehicle to be used for Moon missions, which will be an entirely American built spacecraft.

Because the Orion will not be developed or used in cooperation with ESA, ESA faces a major obstacle for continuation of its manned spaceflight program with the end of the Space Shuttle program by 2010 and the contemplated end of the International Space Station program by 2015/2016.

[edit] Cooperation with Russia

Since 2004, ESA had been in talks with Roskosmos on cooperation for the development of Kliper, the Russian successor project to the Soyuz spacecraft which has been in service for nearly 40 years. While ESA's management was enthusiastic about this cooperation, ESA member states turned down funding for a design and collaboration study in December 2005, mainly because certain member states felt that ESA would just be a minor industrial contributor to the program, while Russia would actually develop and design the Kliper spacecraft.

After the December 2005 rejection of Kliper by ESA, Jean-Jacques Dordain emphasized that a collaboration with Russia on a new spacecraft could still be decided in June 2006. On June 13, 2006 the press reported that the winged Kliper project has been replaced by a study to develop a capsule under the Advanced Crew Transportation System program that ESA is funding.^[4] This rejection by ESA notwithstanding, Kliper was a Russian program that might still be funded entirely by Roskosmos - although this is unlikely if Russia and Europe really go forward with CSTS together. Reasons for going with CSTS include that it gives Europe the possibility to be a full partner in a Russian-European program, because the modular structure (see below) allows for a division of design responsibilities between the partners (for instance, Russia could be in charge of the overall design of the reentry capsule, while ESA works on the habitation module etc.)

About €15 million were pledged for the CSTS program at ESA's regular meeting on June 21 and June 22, 2006 ^{[citations needed]}. Further funding of the study was to have been asked for at the next ESA meeting in July.^[1] Both partners, Russia and ESA, will bear their own costs in the first 2 years of the program. "We are now entering a phase of working with the Russians where we will establish a preliminary design of the vehicle, establish all the legal framework for the operation, delineate the work share for the parties, and outline the aspects of development," said Manuel Valls, head of Policy and Plans Department in ESA's Directorate of Human Spaceflight, Microgravity, and Exploration Program.^[1]

On July 4, 2006 Russian media reported that the head of the Russian Space Agency Anatoly Perminov had met with Jean-Jacques Dordain to discuss the CSTS proposal; however, no agreement was signed between the Russians and Europeans as a result.^[5]

On July 18, 2006 Anatoly Perminov, head of Roskosmos, announced that the Russian tender for the Kliper spacecraft had been cancelled.^[6] It was noted that the ACTS proposal had gained more support among ESA member states than the Kliper design.

[edit] Farnborough Air Show

Jean-Jacques Dordain announced on the Farnborough Air show on July 25, 2006 that the collaborative study together with Roskosmos on the ACTS spacecraft would begin in September 2006 and end early in 2008: So in 18 months' time we will have got a proposal to make to our ministers for the development of such a vehicle.^[7] It was confirmed that ESA's financial contribution to this study would be 15 million EUR, shared among seven ESA member states. The work areas of the study are:

• preliminary system design examining the vehicle's configuration
• detailed subsystem design including a docking mechanism
• development of co-operation mechanisms and agreements, as well as workshare decisions for a full-scale development
• manned lunar flights

[edit] Overall Design

[edit] Three module design^[8]

CSTS ^{[citations needed]}, designed for exploration missions, will feature as re-entry vehicle an improved, Soyuz-type capsule, having increased resources for extended missions duration, improved thermal protection system for reentry into Earth's atmosphere with a higher velocity than just from LEO, new interplanetary navigation systems and possibly an increased size to accommodate a larger crew of 4 members. It will also include a habitation module (like the orbital module on the Soyuz) large enough to accommodate the necessary equipment and resources, as well as to provide the necessary living space to the crew for the longer duration missions. A service module, including attitude control thrusters, oxygen tanks, TCS, Motion Control Systems data handling and distribution, command system, telemetry and feedback the main propulsion system and other subsystems, including solar arrays, electrical power control system, etc.^[4]

The three-part design of CSTS is similar to the one used on Soyuz. The advantages of using such a system instead of the two-part Orion structure (only a crew module that is also used as re-entry module and one service module), is that the re-entry module can be stripped down to a minimum size and weight, as it is not necessary for the crew to stay in the re-entry module for the whole mission duration but the crew can use the habitation module as well. Because the habitation module is discarded before reentry into Earth's atmosphere, it can be made out of light-weight material that does not need to withstand the forces of a re-entry. This approach reduces overall weight of the spacecraft.

[edit] The re-entry module

Soyuz uses a bell-shaped re-entry module that has space for three cosmonauts. Its weight is approximately 2.8 metric tons. The CSTS study will have to decide whether they are using the same bell-shaped form for the 4 crew re-entry module or which other configuration the re-entry module will take (cone-shaped such as the Apollo or the Orion spacecraft). What is clear today is that the re-entry module will be a capsule and not a lifting body ^{[citations needed]}, which reduces complexity of the system. While the Orion crew module is currently designed to weigh over 9 metric tons, the CSTS re-entry capsule will probably weigh much less, as living space for the whole spacecraft is divided into the re-entry module and habitation module.

[edit] The habitation module

For spaceflights beyond LEO, it is necessary to accommodate certain equipment and appliances (toilet etc.) in a spacecraft. This habitation module could be derived from hardware that has already been developed by ESA, that is the Automated Transfer Vehicle or the Columbus Orbital Laboratory ^{[citations needed]}.

[edit] The service module

Power and propulsion needs to be provided by another module. Heritage for this module may come from both the Soyuz spacecraft or the Automated Transfer Vehicle. In light of a mission beyond LEO this module will however be by far the largest of the three modules the spacecraft consists of ^{[citations needed]}.

[edit] Missions beyond LEO

To understand the CSTS mission parameters it is first important to describe what limitations CSTS will have to deal with. Manuel Valls, head of Policy and Plans Department in ESA's Directorate of Human Spaceflight, Microgravity, and Exploration Program noted on the question of available launch vehicles for the CSTS spacecraft that "although nothing at this stage is definitive, [...] both the Russians and we think that it is only prudent, and most efficient and effective, to go with 2 stages and not one. The 1-stage has been done already with Saturn V and Apollo. To do that now would entail the development of quite a new launcher and that will take time and money like hell, if I may say. Going with two stages is far more effective [...] because we could use – and this is our intention – existing launch vehicles or launch vehicles with minimal development."^[1] This means that CSTS will have a tight mass budget, as only launchers with a maximum payload capacity in the class of Ariane 5, Proton or Angara will be available for a launch. With two stages and LEO docking that means that CSTS together with an Earth Departure Stage will not be able to weigh more than about 45 to 50 metric tons in LEO (note however that this is just for the lunar spacecraft, a lunar lander is not integrated in this calculation).

An ESA presentation^[8] from June 13, 2006 however presents a lunar orbital mission of the CSTS spacecraft with 3 launches, of which two are propulsion modules to propel the spacecraft to a trans-lunar trajectory. Such a scenario, while more complicated than the 2-stage approach mentioned by Manuel Valls, gives more leeway in terms of the CSTS' mass budget.

EADS Astrium Space Transportation concepts for adapting the Ariane 5 ECB for lunar exploration could increase Ariane 5 LEO performance to 27 tonnes ^{[citations needed]}. These performance adaptions would entail the use of a composite solid rocket casing, and upgrades to the Vulcain Mk III and Vinci (ECSB) engines.

No information presently available with regard to the CSTS outlines a clear lunar mission scenario.

[edit] Launch Sites

Both the ESA's launch site at French Guiana and the Russian spaceports at Baikonour and Plesetsk are discussed to be utilized for CSTS ^{[citations needed]}.

[edit] See also

• Kliper
• Soyuz
• Orion

[edit] References

1. ^ ^{a b c d e} http://www.planetary.org/news/2006/0628_Europe_and_Russia_Join_Forces_to_Study.html
2. ^ http://www.sron.nl/files/PB/downloads/ESA%20Exploration.pdf^{[citations needed]}
3. ^ http://www.spiegel.de/wissenschaft/weltall/0,1518,443901,00.html
4. ^ ^{a b} Kliper dropped for lunar capsule
5. ^ http://www.mosnews.com/news/2006/07/04/russianasaiss.shtml
6. ^ http://www.flightglobal.com/Articles/2006/07/18/Navigation/177/207935/Farnborough+Russia's+Federal+Space+Agency+cancels+manned+spacecraft.html
7. ^ http://www.flightglobal.com/Articles/2006/07/25/Navigation/177/208008/Farnborough+Crew+transport+work+to+start.html
8. ^ ^{a b} http://www.belspo.be/belspo/eisc/pdf/docu2p_eisc/DeWinne.pdf

[edit] External links

• Russia New Russian spaceship will be able to fly to Moon - space corp
• Ariane 5 – A European Launcher for Space Exploration
• RSC Energia: Concept Of Russian Manned Space Navigation Development
• ESA presentation on CSTS dated June 13, 2005 (pdf)
• Europe and Russia Join Forces to Study Advanced Crew Transportation System
• Russia FSA cancels manned spacecraft tender
• ESA, Russia to Collaborate on New Spacecraft Design
• ESA to finalise manned capsule contributions at July meeting