One of the challenges Russian designers faced in developing the next-generation spacecraft in the first decade of the 21st century was the need for a new rocket to launch it. Since the future ship replacing Soyuz would have to carry six instead three crewmembers and weigh from 12 to 23 tons, it would need much larger launch vehicle than existing Soyuz rocket capable of carrying just seven tons to the low-Earth orbit. Developers had few options to consider among existing rockets:
Although several ways of upgrading the Soyuz rocket had been evaluated in the middle of decade within Soyuz-2-3 and Soyuz-3 programs, Russian space agency ultimately came to realize that the overall architecture of the Soyuz rocket was too obsolete for the new tasks of the 21st century;
Any idea of using the existing Proton rocket, which did have required lifting capacity, would be out of the question, since the vehicle used toxic propellants and the agency’s policy was to phase out the rocket, as soon as the replacement Angara family becomes available;
The Proton replacement — the Angara rocket — had been in development since the beginning of the 1990s and with considerable investments already committed to the project, it was expected to fly its first mission in 2011. However the vehicle was primarily intended for delivering military and commercial satellites from its newly built launch pad in Plesetsk. Giving the role of the manned launcher to Angara would essentially leave the entire Russian rocket fleet in the hands of a single contractor — Khrunichev enterprise, clearly to be avoided “all eggs in one basket” strategy. In the meantime, existing “alternative” developer of the Soyuz rocket — TsSKB Progress in Samara — could be out of the job.
The Zenit rocket could carry a minimal mass considered for the next-generation spacecraft and it also provided a newer design than that of Soyuz and Proton. It could potentially upgraded for higher payloads. However, after the collapse of the Soviet Union, the production of the vehicle ended up outside Russia, in Ukraine, making it politically unacceptable for nation’s goal of maintaining independent access to space. Organizing production of the Zenit in Russia could be considered, however it would require sizable investments, perhaps approaching the potential cost of the development of the whole new rocket. In the meantime, the vehicle itself would provide only marginal capability for lunar missions.
Development of the whole new family of rockets
Around 2008, the development of the whole new family of rockets for manned spaceflight had become attractive to the Russian government, especially in light of a decision in the previous year to build a new Vostochny launch site.
A strategic decision to place the space center in the Russian Far East brought up the issue of transporting the vehicles to the region from the industrial centers in western Russia. The size of rocket stages would either have to be limited by the capabilities of railway transport, or the Russian government would have to commit to the development of a compatible air transportation system. Finally, the third alternative would be the development of a whole new manufacturing base right there in the Far East. Despite being probably the most expensive and economically difficult proposition, it would match the political goal of the Russian government to industrialize this isolated and sparsely populated region.
Choosing the developer
Upon committing to the development of the new vehicle, Russian space agency had to decide about the design of the future rocket and choose its manufacturer. During 2008, all major rocket “firms” competed with their configurations for the role of building a future manned launcher. In the third quarter of 2008, the “system evaluation” of possible architecture of the future vehicle was completed and several proposals for the rocket were apparently submitted to Roskosmos by Sept. 1, 2008.
Although Roskosmos made no formal announcement on the matter at the time, unofficial postings on the forum of the Novosti Kosmonavtiki magazine indicated that the agency favored a two-stage launch vehicle developed by the conglomerate of RKK Energia in Podlipki, TsSKB Progress in Samara and KB Mashinostroeniya in Miass. TsSKB Progress would have bear overall responsibility for the launch vehicle and its second stage. KB Mashinostroeniya would develop the first stage. Finally, RKK Energia was expected to have over responsibility for the manned transport system. Thus, all key players in the industry would retain their traditional responsibilities and preserve their workforce.
Design requirements
The first stage of the medium-lifting rocket favored by Roskosmos would apparently consist of three standard boosters equipped with RD-180 engines. Its unmanned version would have to deliver 23.8 tons to the 200-kilometer orbit with the inclination 51.7 degrees after the launch from Vostochny. The man-rated version would have to be capable of delivering a 18.8-ton spacecraft to a minimum 135 by 440-kilometer orbit, from which its descent module would be able to conduct an emergency reentry and landing just north of the launch site, while subjecting the crew to no more than 12 g. In case of a single-engine failure on the first stage, the rocket was required to make a splashdown in the Pacific Ocean, using the thrust of two remaining engines.
In an interview with BBC, Aleksandr Chulkov, the head of launch vehicle and infrastructure directorate, confirmed that the launch vehicle would have to be able to carry at least 20 tons and maximum 23 tons to the low-Earth orbit. Within Russian nomenclature, the new rocket would be classified as a medium-lifting vehicle, while heavy-lifting vehicles would be capable of delivering from 35 to 50 tons to the low-Earth orbit. Chulkov said that requirements for heavy-lifting capabilities within the manned space program would be met by the Angara family of rockets. Still, the new rocket equipped with five standard boosters on the first stage instead of three would be able to deliver 35 tons to the low-Earth orbit, while another variation, including four standard boosters on the first stage and one on the second stage, could carry 50 tons.
Since the Technical Assignment for the program reportedly required the construction of as many as 15 launchers, it could require the production of as many as 45 engines a year. With the moderate rate of four launches a year, 12 engines would be required annually. Due to such high numbers of required engines and the need to produce same hardware for the American Atlas rocket, it looked possible that an additional manufacturer based in the city of Perm would be brought into the project. The same company was responsible for mass production of RD-191 engine for the Angara rocket.
The second stage of the vehicle had to be powered either by kerosene or hydrogen according to the Technical Assignment of the Russian space agency. The head of the Russian space agency, Roskosmos, Anatoly Perminov told Russian press that hydrogen would be used on the second stage.
According to unofficial reports, a formal opening of envelopes with industry proposals on the new rocket would take place on March 16, 2009. The commission was then expected to make a decision on March 19. Chulkov said that Roskosmos would have 10 days to complete the formal review of all proposals and the agency would pick a winner by March 25, 2009. The key consideration would be cost-effectiveness of the proposal, Chulkov said. The decision would be followed by the preliminary development of the project, which was expected to last for around one year.
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