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Dragon V2 (aka Crew Dragon, or Dragon 2, and formerly, DragonRider) is the second version of the SpaceX Dragon spacecraft which will be a human-rated vehicle capable of making a terrestrial soft landing.〔 〕 It includes a set of four side-mounted thruster pods with two SuperDraco engines each which can serve as a Launch Abort System (LAS) or be used for propulsive landings. In addition, it has much larger windows, landing legs which extend from the bottom of the spacecraft, new computers and avionics, and redesigned solar arrays, all packaged in a spacecraft with a changed outer mold line from the initial cargo Dragon that has been flying for several years. The spacecraft was unveiled on May 29, 2014—after originally being expected to be unveiled in 2013 —a crew-carrying variant of Dragon that varies considerably from the cargo-carrying Dragon, which has been operational since 2010. Dragon V2 could make its first flight as early as late 2016, with its first flight with people as early as 2017. A launch pad abort test of Dragon V2 was completed on 6 May 2015, although it had earlier been planned to occur as early as late-2014.〔 〕〔 〕〔 〕 NASA has signed a contract to procure up to six crew-carrying flights to the International Space Station under the Commercial Crew Development. ==Dragon V2 development history== The crewed variant of Dragon was initially called ''DragonRider''.〔 〕 It was intended from the beginning to support a crew of seven or a combination of crew and cargo. It was planned to be able to perform fully autonomous rendezvous and docking with manual override capability; and was designed to use the NASA Docking System (NDS) to dock to the ISS.〔(【引用サイトリンク】title=Dragon Overview )〕 For typical missions, DragonRider would remain docked to the ISS for a period of 180 days, but would be designed to be able to do so for 210 days, the same as the Russian Soyuz spacecraft. From the earliest design concepts which were publicly released in 2010, SpaceX planned to use an integrated pusher launch escape system for the Dragon spacecraft, claiming several advantages over the tractor detachable tower approach used on most prior crewed spacecraft.〔With the exception of the Project Gemini spacecraft, which used twin ejection seats: ("Encyclopedia Astronautica: Gemini Ejection" ). Astronautix.com. Retrieved 24 January 2013.〕〔("Spaceship teams seek more funding" ). MSNBC Cosmic Log. 10 December 2010. Retrieved 14 December 2010.〕 These advantages include the provision for crew escape all the way to orbit, reusability of the escape system, improved crew safety due to the elimination of a stage separation, and the ability to use the escape engines during the landing phase for a precise solid earth landing of the Dragon capsule. An emergency parachute system will be retained as a redundant backup for water landings.〔 , the Paragon Space Development Corporation was assisting in the development of DragonRider's life support system. In 2012, SpaceX was in talks with Orbital Outfitters regarding the development of a spacesuit that would be worn during launch and re-entry. At a NASA news conference on 18 May 2012, SpaceX confirmed again that their target launch price for crewed Dragon flights is $160,000,000, or $20,000,000 per seat if the maximum crew of 7 is aboard, and if NASA orders at least four DragonRider flights per year.〔 〕 This contrasts with the 2014 Soyuz launch price of $76,000,000 per seat for NASA astronauts. In October 2014, NASA selected the Dragon spacecraft as one of the candidates to fly American astronauts to the International Space Station under the Commercial Crew Program. SpaceX plans to use the Falcon 9 launch vehicle for launching Dragon V2.〔http://www.spacex.com/news/2014/09/16/nasa-selects-spacex-be-part-americas-human-spaceflight-program〕〔 SpaceX intends to certify their propulsive landing scheme in parallel with the parachute-to-water-landing method for Dragon V2, with the goal to hold to the development schedule and "ensure U.S. crew transportation safely and reliably in 2017. Land landing will become the baseline for the early post-certification missions" while precision water landing under parachutes was proposed to NASA as "the baseline return and recovery approach for the first few flights of Crew Dragon."〔 Following the successful test of the launchpad abort system in May 2015, Elon Musk indicated that the Dragon capsule platform, launched on a Falcon Heavy launch vehicle, could be used to transport robotic science payloads across much of the solar system, including the Jovian moon Europa, Mars, or Earth's Moon.〔 〕 Musk indicated that Dragon could transport of useful payload to the surface of Mars. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Dragon V2」の詳細全文を読む スポンサード リンク
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