Ares Crew Launch Vehicle (CLV)
Going forward, the Agency will need a launch system for the CEV, one which does not at present exist. Two possibilities exist by which NASA might obtain such a vehicle. The first is to develop a launch system derived from Shuttle components, specifically the SRB with a new upper stage. The second option is to upgrade the proposed heavy-lift versions of EELV with a new upper stage. A key aspect of the Agency's analysis of alternatives will be to capitalize on existing technical and workforce assets in a cost-effective and efficient way. NASA's goal is to develop a CEV capable of operating safely soon after the retirement of the Space Shuttle.
The space transportation capabilities necessary to carry out space exploration will be developed consistent with US Space Exploration Policy, dated 14 January 2004. Consistent with that direction, the Administrator of the National Aeronautics and Space Administration were directed on 21 December 2004 by National Security Presidential Directive-40 (NSPD-40) U.S. Space Transportation Policy to develop, in cooperation with the Secretary of Defense as appropriate, options to meet potential exploration-unique requirements for heavy lift beyond the capabilities of the existing Evolved Expendable Launch Vehicles.
These options will emphasize the potential for using derivatives of the Evolved Expendable Launch Vehicles to meet space exploration requirements. In addition, the NASA Administrator was directed by NSPD-40 to evaluate the comparative costs and benefits of a new dedicated heavy-lift launch vehicle or options based on the use of Shuttle-derived systems.
Analysis found that significant campaign cost reductions were available by replacing the 5- and 7 core EELV with Shuttle derived side-mount LV. The vast majority of payloads are launched on SDLV -- the CEV + TLI is launched on 1 SD LV reducing the number of in-space rendezvous. In one abalysis, this decreased in number of launches by 17 (from 80 to 63); decreased in number of EELV cores by 404 (from 421 to 17); increased the probability of no LOM events during campaign from 5.4% to 35.0%; and decreased the LOC for a campaign from 1 in 24 to 1 in 68. Mission risk and Crew risk were dramatically decreased by the use of shuttle derived launch vehicles. Overall, campaign programmatic and technical risks were reduced significantly.
As of mid-2005 plans called for the spacecraft required for lunar missions would be launched on a 40-story tall booseter built around a modified version of the shuttle's external fuel tank. This heavy lift launch vehicle would be developed between 2010 and 2018. Propulsion would consist of five Space Shuttle Main Engines, and larger versions of the Solid Rocket Motors. Some variants could carry a payload of 125 tons into Low Earth Orbit, nearly equal to the Saturn 5. The projected launch cost of $540 million per flight, comparable to some calculations of the cost of a shuttle mission [other estimates sugggest the Shuttle is closer to one billion per flight].
The new booster would have a new upper stage, the Earth Departure Stage [EDS], whihc would be used place payloads into a lunar-bound trajectory. The EDS would also be derived from the shuttle's External Tank, with a pair of upgraded J-2 engines used on the Saturn 5's upper stages.
The Crew Exploration Vehicle would be launched on a separate rocket, derived from the Solid Rocket Motor. The booster's new second stage would feature a single SSME derived engine. Starting in June 2011, the $280 million missions initially conduct space station flights. The booster would later be used to put crews into low Earth orbit to embark on trips to the moon.
In June 2006, NASA announced the launch vehicles under development by the Constellation Program have been named Ares, a synonym for Mars. The booster that will launch Orion will be called Ares I, and a larger heavy-lift launch vehicle will be known as Ares V.
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