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The VSS ''Enterprise'' (tail number: N339SS〔(【引用サイトリンク】title=FAA N Number Registration for "VSS Enterprise" )〕) was the first SpaceShipTwo (SS2), built by Scaled Composites for Virgin Galactic. As of 2004, it was planned to be the first of five commercial suborbital SS2 spacecraft planned by Virgin Galactic.〔 〕〔 (【引用サイトリンク】 Scaled Composites PROJECTS )〕 It was also the first ship of the Scaled Model 339 SpaceShipTwo class, based on upscaling the design of record-breaking SpaceShipOne. The VSS ''Enterprises name was an acknowledgement of the USS ''Enterprise'' from the ''Star Trek'' television series.〔 (【引用サイトリンク】 SpaceShipTwo )〕 The spaceplane also shared its name with NASA's prototype space shuttle, as well as the aircraft carrier USS ''Enterprise''. It was rolled out on 7 December 2009.〔 (【引用サイトリンク】 url = http://www.virgingalactic.com/news/item/spaceshiptwo-roll-out/ )〕 SpaceShipTwo made its first powered flight in April 2013. Richard Branson said it "couldn't have gone more smoothly". ''Enterprise'' was destroyed during a powered test flight on 31 October 2014, killing one pilot and seriously injuring another. A preliminary investigation suggests the "feathering" system, the ship's descent device, deployed too early. ==Flight test program== Initial projections by Virgin Galactic in 2008 called for test flights to begin in late 2009 and commercial service to start in 2011.〔 〕 This schedule was not achieved, with captive carry and glide flight tests beginning in 2010, and the first test flight under rocket power was not until 2013. In October 2009, Virgin Galactic CEO Will Whitehorn outlined the flight test program for SpaceShipTwo. The test program includes seven phases: # Vehicle ground testing # Captive carry under White Knight Two # Unpowered glide testing # Subsonic testing with only a brief firing of the rocket # Supersonic atmospheric testing # Full flight into suborbital space # Execute a detailed and lengthy appraisal process with the FAA/AST to demonstrate the system's robustness and eventually obtain a commercial launch license to begin commercial operations. On 22 March 2010, the SpaceShipTwo vehicle VSS ''Enterprise'' underwent a captive carry test flight, with the parent White Knight Two aircraft, VMS ''Eve'', performing a short flight while carrying the ''Enterprise''. A second test flight was made on 16 May 2010,〔 (【引用サイトリンク】title= WhiteKnightTwo/SpaceShipTwo Test Summaries )〕 reaching SS2's launch altitude (51,000 feet) and lasting nearly five hours, in order to facilitate "cold soak" testing of SS2's avionics and pressurization system. Thereafter, "a simulated spaceship descent/glide mission was made from () altitude."〔 〕 Between these two flights, the SpaceShipTwo airframe was modified by the addition of two interior fins, with one fin being added to the inside (rocket-side) of each of the craft's twin vertical stabilizers.〔 〕 On 15 July 2010, VSS ''Enterprise'' made its first crewed flight. The craft remained attached to VMS ''Eve'' as planned, and underwent a series of combined vehicle systems tests. The flight lasted a total of 6 hours and 21 minutes. A second, similar crewed flight of VSS ''Enterprise'' and VMS ''Eve'' was carried out on 30 September 2010, lasting approximately 5 hours. Among the objectives of these flights was the improvement of pilot proficiency, and the results of the flights were deemed to show that the systems were capable of supporting future glide missions.〔 (), ''Virgin Galactic'', accessed 17 July 2010.〕 On 10 October 2010, VSS ''Enterprise'' made its first manned gliding test flight. It was released from VMS ''Eve'' at 13700 m feet and glided to a safe landing at the Mojave Air and Spaceport.〔 〕 A second gliding test flight took place on 28 October 2010 and a third on 17 November 2010.〔 〕 , Scaled reported that the flight test program is exceeding expectations.〔 〕 The fourth test flight took place on 13 January 2011, while the fifth and sixth glide flights occurred on 22 and 27 April 2011, respectively. Following this, the feathered reentry configuration was tested in flight on 4 May 2011,〔 with weekly test flights continuing through the end of May.〔 On 9 June 2011, SS2 failed to separate from White Knight Two during its 11th planned glide flight due to a technical problem.〔(【引用サイトリンク】title= WhiteKnightTwo flight test summaries )〕 Testing resumed with five successful glide flights in June 2011.〔 In July 2011, after 15 successful glide flights, flight testing of SS2 was halted for two months while planned revisions to the spaceplane were made.〔 〕 Flight tests resumed in late September 2011, although the 16th glide flight – on 29 September – was marred by a brief loss of control aboard SS2, forcing the crew to utilise the feathered wing configuration to land safely. This test was followed by another hiatus, during which some of the spacecraft's engine components were installed. In June 2012, Scaled Composites received an FAA permit to conduct rocket-powered supersonic test flights.〔(【引用サイトリンク】title= SpaceShipTwo Gets Thumbs Up for Rocket-Powered Flights )〕 SpaceShipTwo flight tests resumed in June 2012.〔〔(【引用サイトリンク】title= Virgin Galactic successfully completes SpaceShipTwo glide flight test and rocket motor firing on same day )〕 In September 2012, Virgin Galactic announced that the unpowered subsonic glide flight test program was essentially complete. The company thereafter stated its intention to fit the hybrid rocket motor and control system to the vehicle, before resuming the glide flight test program with the rocket motor installed, in order to recharacterize the spacecraft's glide performance with slightly different weight distribution and aerodynamics. In October 2012, Scaled Composites installed key components of the rocket motor, and SpaceShipTwo performed its first glide flight with the engine installed in December 2012.〔 The spacecraft's first powered test flight took place on 29 April 2013, briefly driving SpaceShipTwo to a supersonic velocity.〔 Richard Branson said it "couldn't have gone more smoothly".〔 On 5 September 2013, the second powered flight was made by the SpaceShipTwo. It broke the sound barrier achieving a speed of mach 1.43, and climbed to 69.000 feet (21 km) over the Mojave Desert under rocket power and descended using its tilt-wing "feathering" maneuver.〔(【引用サイトリンク】url= http://www.forbes.com/sites/alexknapp/2013/09/05/virgin-galactics-spaceshiptwo-succeeds-in-second-rocket-powered-flight/ )〕 Space journalist Doug Messier reported that "the engine plume featured white smoke, not the black smoke seen on the April flight."〔 〕 On 10 January 2014, the third powered flight climbed higher than the previous flights, testing a new coating on the tail boom and other systems.〔 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「VSS Enterprise」の詳細全文を読む スポンサード リンク
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