Dream Chaser

From Wikipedia, the free encyclopedia
  (Redirected from Dream Chaser (spacecraft))
Jump to navigation Jump to search

Dream Chaser Cargo System
Dream Chaser flight test vehicle in 2013
Dream Chaser flight test vehicle in 2013
ManufacturerSierra Nevada Corporation
Country of originUnited States
OperatorNASA
ApplicationsISS resupply
Specifications
Spacecraft typeRobotic cargo vehicle
Payload capacity5,000 kg (5.0 t; 11,000 lb) pressurized, 500 kg (0.50 t; 1,100 lb) unpressurized
Production
StatusIn development
Related spacecraft
Derived fromHL-20 Personnel Launch System

The Dream Chaser Cargo System is a US reusable lifting body spaceplane being developed by Sierra Nevada Corporation (SNC) Space Systems. Originally intended as a crewed vehicle, the Dream Chaser Space System would have been capable of carrying up to seven people to and from low Earth orbit.

The cargo Dream Chaser will resupply the International Space Station with both pressurized and unpressurized cargo. The vehicle will launch vertically on a Vulcan Centaur rocket[1] and autonomously land horizontally on conventional runways.[2]

Spacecraft[edit]

Dream Chaser engineering test article

The Dream Chaser design is derived from NASA's HL-20 Personnel Launch System spaceplane concept,[3] which in turn is descended from a series of test vehicles, including the X-20 Dyna-Soar, Northrop M2-F2, Northrop M2-F3, Northrop HL-10, Martin X-24A and X-24B,[4][5][6] and Martin X-23 PRIME.[7]

Technology partners[edit]

In 2010, the following organizations were named as technology partners for the original passenger Dream Chaser:[8]

Propulsion[edit]

On-orbit propulsion of the Dream Chaser was originally proposed to be provided by twin hybrid rocket engines capable of repeated starts and throttling. At the time, SNC Space Systems was also developing a similar hybrid rocket for Virgin Galactic's SpaceShipTwo.[11] In May 2014, SNC involvement in the SpaceShipTwo program ended.[12]

After the acquisition of Orbitec LLC in July 2014, Sierra Nevada Corporation announced a major change to the propulsion system. The hybrid rocket engine design was dropped in favor of a cluster of Orbitec's Vortex engines. The new engines would use propane and nitrous oxide as propellants.[13]

Crewed version[edit]

Artist's conception of the Dream Chaser Space System in the launch configuration

The originally planned Dream Chaser Space System is a human-rated version designed to carry from two to seven people and cargo to orbital destinations such as the International Space Station.[14] It is to have a built-in launch escape system[11] and could fly autonomously if needed.[15] Although it could use any suitable launch vehicle, it is currently planned to be launched on a human-rated Atlas V 412 rocket.[15][16] The vehicle is to be able to return from space by gliding (typically experiencing less than 1.5 g on re-entry) and landing on any airport runway that handles commercial air traffic.[17][8] Its reaction control system thrusters burn ethanol-based fuel,[15][17] which is not an explosively volatile material, nor toxic like hydrazine, allowing the Dream Chaser to be handled immediately after landing, unlike the Space Shuttle.[15] Its thermal protection system (TPS) will be made up of silica-based tiles and a new composite material called Toughened Unipiece Fibrous Reusable Oxidation Resistant Ceramic (TUFROC).[18][19]

CRS-2 cargo version[edit]

Artist's conception of the crewed Dream Chaser docked to ISS

Currently[when?] under development, the cargo version of the SNC Dream Chaser is called the Dream Chaser Cargo System and will fly resupply flights to the ISS under NASA's Commercial Resupply Services-2 program. Featuring an expendable cargo module mounting solar panels, the spacecraft will be capable of returning 1,750 kg (3,860 lb) to Earth while undergoing maximum re-entry forces of 1.5G.[20][21]

To meet CRS-2 guidelines, the cargo Dream Chaser will have folding wings and fit within a 5 m diameter payload fairing, in contrast to Crew Dream Chaser, which is intended to launch without a fairing. The ability to fit into a payload fairing allows the cargo version to launch on any sufficiently capable vehicle, such as Ariane 5 as well as Atlas V. An expendable cargo module will launch attached to the aft end of the spacecraft, expanding the cargo uplift capacity and supporting the disposal of up to 3,250 kg (7,170 lb) of trash. Total uplift is planned for 5,000 kg (11,000 lb) pressurized and 500 kg (1,100 lb) unpressurized, with a downlift of 1,750 kg (3,860 lb) contained within the spaceplane.[22]

On August 14, 2019, it was announced that all six Dream Chaser CRS-2 flights will be carried into orbit by ULA's Vulcan launch vehicle, with the first Dream Chaser flight being the second Vulcan flight in late 2021.[1][23]

Program history[edit]

The name "Dream Chaser" had been previously used for two separate space vehicle concepts. The first was planned to be an orbital vehicle based on the HL-20, with the second suborbital vehicle proposed by the Benson Space Company for the purposes of space tourism.[24]

The Dream Chaser was publicly announced on September 20, 2004.[25] In April 2007, SpaceDev announced that it had partnered with the United Launch Alliance to pursue the possibility of using the Atlas V booster rocket as the Dream Chaser's launch vehicle.[26] In June 2007, SpaceDev signed a Space Act agreement with NASA.[27]

On 21 October 2008, Dream Chaser was acquired by the Sierra Nevada Corporation for US$38 million.[28]

CCDev phase 1[edit]

On 1 February 2010, Sierra Nevada Corporation was awarded $20 million in seed money under NASA's Commercial Crew Development (CCDev) phase 1 program for the development of the Dream Chaser.[29][30] SNC completed the four planned milestones on time, including hybrid rocket test fires and the preliminary structure design.[31] Further initial Dream Chaser tests included the drop test of a 15% scaled version at the NASA Dryden Flight Research Center.[32]

CCDev phase 2[edit]

Sierra Nevada proposed Dream Chaser for the CCDev phase 2 solicitation by NASA in October 2010, with an estimated project cost of less than $1 billion.[33][34] On 18 April 2011, NASA awarded $80 million to Sierra Nevada Corporation for Dream Chaser.[35] Since then, nearly a dozen further milestones have been completed under that Space Act Agreement. Some of these milestones included testing of an improved airfoil fin shape, integrated flight software and hardware, landing gear, a full-scale captive carry flight test, and a Systems Requirement Review (SRR).[36][37]

By February 2012, Sierra Nevada Corporation stated that it had completed the assembly and delivery of the primary structure of the first Dream Chaser flight test vehicle. With this, SNC completed all 11 of its CCDev milestones that were scheduled up to that point. SNC stated in a press release that it was "on time and on budget."[38]

On 29 May 2012, the Dream Chaser Engineering Test Article (ETA) was lifted by an Erickson Skycrane helicopter in a captive carry test to better determine its aerodynamic properties.[39][40] In May 2013, the ETA was shipped to the Dryden Flight Research Center in California for a series of ground tests and aerodynamic flight tests.[41] A second captive carry flight test was completed on 22 August 2013.[42]

On 12 June 2012, SNC announced the commemoration of its fifth year as a NASA Langley partner in the design and development of Dream Chaser.[43] The NASA/SNC team had worked on aerodynamic and aerothermal analysis of Dream Chaser, as well as guidance, navigation, and control systems. Together with ULA, the NASA/SNC team performed buffet tests on the Dream Chaser and Atlas V stack.[43]

On 11 July 2012, SNC announced that it successfully completed testing of the nose landing gear for Dream Chaser.[44] This milestone evaluated the impact to the landing gear during simulated approach and landing tests as well as the impact of future orbital flights. The main landing gear was tested in a similar way in February 2012. The nose gear landing test was the last milestone to be completed before the free flight approach and landing tests scheduled for later in 2012.[44] In August 2012, SNC completed CCiCap Milestone 1, or the ‘Program Implementation Plan Review’. This included creating a plan for implementing design, development, testing, and evaluation activities through the duration of CCiCap funding.[45] By October 2012 the "Integrated System Baseline Review", or CCiCap Milestone 2, had been completed. This review demonstrated the maturity of the Dream Chaser Space System as well as the integration and support of the Atlas V launch vehicle, mission systems, and ground systems.[45]

CCiCap[edit]

On 3 August 2012, NASA announced the award of $212.5 million to Sierra Nevada Corporation to continue work on the Dream Chaser under the Commercial Crew Integrated Capability (CCiCap) Program.[46] On 30 January 2013, SNC announced a new partnership with Lockheed Martin. Under the agreement, SNC will pay Lockheed Martin $10 million to build the second airframe at its Michoud facility in New Orleans, Louisiana. This second airframe is slated to be the first orbital test vehicle, with orbital flight testing planned to begin within the next two years.[9]

In January 2013, Sierra Nevada announced that the second captive carry and first unpowered drop test of Dream Chaser would take place at Edwards Air Force Base, California in March 2013. The spaceplane release would occur at 12,000 feet (3,700 m) altitude and would be followed by an autonomous robotic landing.[9][10]

On 13 March 2013, NASA announced that former space shuttle commander Lee Archambault was leaving the agency in order to join SNC. Archambault, a former combat pilot and 15-year NASA veteran who flew on Atlantis and Discovery, will work on the Dream Chaser program as a systems engineer and test pilot.[47][48]

On October 26, 2013, the first free-flight occurred. The test vehicle was released from the helicopter and flew the correct flightpath to touchdown less than a minute later. Just prior to landing, the left main landing gear failed to deploy resulting in a crash landing.[49] The vehicle skidded off the runway in a cloud of dust, but was found upright with the crew compartment intact and all systems inside still in working order.[50][51]

In January 2014, SNC announced it had signed a launch contract to fly the first orbital test vehicle on a robotically controlled orbital test flight in November 2016.[52]

Dream Chaser model being tested at NASA Langley.

In early 2014, Sierra Nevada completed its wind tunnel testing as part of its CCiCAP Milestone 8. The wind tunnel testing involved analyzing the flight dynamics characteristics that the vehicle will experience during orbital ascent and re-entry. Wind tunnel testing was also completed for the Dream Chaser Atlas V integrated launch system. These tests were completed at NASA Ames Research Center at Moffett Field, California, CALSPAN Transonic Wind Tunnel in New York, and at NASA Langley Research Center Unitary Plan Wind Tunnel in Hampton, Virginia.[53]

On 1 August 2014, the first completed piece of the orbital Flight Test Article (FTA) composite airframe was unveiled at a Lockheed Martin facility.[54]

CCtCap[edit]

On 16 September 2014, NASA did not select the Dream Chaser for the next phase of the Commercial Crew Program. This occurred despite previous Commercial Crew Development awards in every phase since 2009,[55] due to lack of maturity.[56]

On 26 September, Sierra Nevada filed a protest to the US Government Accountability Office (GAO).[57] On 22 October 2014, a Federal Judge ruled the contract awards to Boeing and SpaceX valid, allowing NASA to proceed.[58]

On 29 September 2014, Sierra Nevada introduced the "Dream Chaser Global Project" which would provide customized access to low Earth orbit to global customers.[59]

Despite not being selected to continue forward under NASA's Commercial Crew transportation Capability (CCtCap) phase of the effort to send crews to orbit via private companies, SNC completed the milestones assigned under earlier phases of the CCP.[60] On December 2, 2014 SNC announced that it completed NASA's CCiCap Milestone 5a related to propulsion risk reduction for the Dream Chaser space system.[61]

By late December, details had emerged that "a high-ranking agency official"—"William Gerstenmaier, the agency's top human exploration official and the one who made the final decision"—"opted to rank Boeing's proposal higher than a previous panel of agency procurement experts." More specifically, Sierra Nevada asserted in their filings with the GAO that Gerstenmaier may have "overstepped his authority by unilaterally changing the scoring criteria."[62]

On January 5, 2015, the GAO denied Sierra Nevada's CCtCap challenge, stating that NASA made the proper decision when it decided to award Boeing $4.2 billion and SpaceX $2.6 billion to develop their vehicles. Ralph White, the GAO's managing associate counsel, announced that NASA "recognized Boeing's higher price but also considered Boeing's proposal to be the strongest of all three proposals in terms of technical approach, management approach and past performance, and to offer the crew transportation system with most utility and highest value to the government." Furthermore, the agency found "several favorable features" in SNC's proposal "but ultimately concluded that SpaceX's lower price made it a better value."[63]

CRS-2 selection[edit]

In December 2014, Sierra Nevada proposed Dream Chaser for CRS-2 consideration.[64] In January 2016, NASA announced that Dream Chaser had been awarded one of the CRS-2 contracts and committed to purchasing a minimum of six resupply missions to the ISS.[65] The cargo spacecraft will fly alongside spacecraft from the existing CRS-1 contract holders SpaceX and Orbital Sciences.[66]

In October 2015, the thermal protection system was installed on the Engineering Test Article (ETA) for the next phase of atmospheric flight testing. The orbital cabin assembly of the Flight Test Article (FTA) was also completed by contractor Lockheed Martin.[67]

In 2015, the ETA had reportedly been given the name Eagle,[41] while the FTA was originally named Ascalon before being changed to Ascension.[68]

On 11 November 2017, the Dream Chaser ETA was released from an altitude of 3,700 m and successfully landed at Edwards AFB.[69][70]

As of August 2019, the first ISS flight of the Dream Chaser is planned for 2021.[1] As of March 2019, completion of NASA's Integrated Review Milestone 5 (IR5) confirms that development is still on schedule.[71][72]

Dream Chaser Global Project[edit]

In December 2013, the German Aerospace Center (DLR) announced a funded study to investigate ways in which Europe might take advantage of the Dream Chaser crewed spaceplane technology. Named the DC4EU (Dream Chaser for European Utilization), the project will study using it for sending crews and cargo to the ISS and on missions not involving the ISS, particularly in orbits of substantially greater altitude than the ISS can reach.[73]

In January 2014, the European Space Agency (ESA) agreed to be a partner on the DC4EU project, and will also investigate whether the Dream Chaser can use ESA avionics and docking mechanisms. ESA will also study launching options for the "Europeanized" Dream Chaser, particularly whether it can be launched within the Ariane 5's large aerodynamic cargo fairing – or, like the Atlas V, without it. In order to fit within the fairing, the Dream Chaser's wing length will have to be reduced slightly, which is thought to be easier than going through a full aerodynamic test program to evaluate and prove it along with the Ariane for flight without the fairing.[74]

In late January 2014, it was announced that the Dream Chaser orbital test vehicle was under contract to be launched on an initial orbital test flight, using an Atlas V rocket, from Kennedy Space Center in November 2016. This is a privately arranged commercial agreement, and is funded directly by Sierra Nevada and is not a part of any existing NASA contract.[52]

In September 2014, SNC announced that it would, with global partners, use the Dream Chaser as the baseline spacecraft for orbital access for a variety of programs, specializing the craft as needed.[75]

On 5 November 2014, SNC's Space Systems team publicly presented the challenges and opportunities related to landing the Dream Chaser spacecraft at public-use airports.[76] Dream Chaser uses standard landing aids and non-toxic propellants that require no special handling.[77]

Dream Chaser for European Utilization[edit]

On February 3, 2015, the Sierra Nevada Corporation's (SNC) Space Systems and OHB System AG (OHB) in Germany announced the completion of the initial Dream Chaser for European Utilization (DC4EU) study.[78]

The study found that Dream Chaser is suitable for a broad range of space applications and could be used to advance European interests in space.[79] The cooperation was renewed in April 2015 for additional two years.[79]

United Nations[edit]

The United Nations Office for Outer Space Affairs (UNOOSA) selected the cargo Dream Chaser for its first space launch. This launch is intended to last for at least two weeks in freeflight to provide space access to United Nations member states that have no space programs of their own. The proposed mission would launch as soon as 2021.[80]

See also[edit]

Spaceplanes

Other ISS cargo vehicles:

Other ISS crew vehicles:

References[edit]

  1. ^ a b c "SNC Selects ULA for Dream Chaser® Spacecraft Launches". Sierra Nevada Corporation (Press release). August 14, 2019. Retrieved August 14, 2019.
  2. ^ "Dream Chaser Model Drops in at NASA Dryden" (Press release). Dryden Flight Research Center: NASA. December 17, 2010. Archived from the original on January 7, 2014. Retrieved August 29, 2012.
  3. ^ Dream Chaser Builds on Decades of Experience, source, Beforeitsnews
  4. ^ H. Phillips, Edward (July 15, 1991). "Langley Refines Design, Begins Human Factors Tests of Personnel Launch System". Aviation Week & Space Technology. p. 52. ...The HL-20’s baseline design has evolved from manned lifting bodies flown for the Defense Dept, during the 1960s and owes much of its overall layout to the Martin X-24A...
  5. ^ Wallace, Lance E. (1996). "Flights of Discovery: 50 Years at the NASA Dryden Flight Research Center" (PDF). NASA. p. 72. Archived from the original (PDF) on February 17, 2015. ...The lifting-body program came to an official end in 1975. Yet like a Phoenix rising from the ashes, the concept has appeared several times since then in proposed NASA spacecraft. When the Langley Research Center revealed its HL-20 design for an emergency crew return vehicle or small mini-Shuttle in 1990, the shape was remarkably similar to the HL-10 and X-24A designs...
  6. ^ R. Asker, James (September 24, 1990). "NASA Design for Manned Spacecraft. Draws on Soviet Subscale Spaceplane". Aviation Week & Space Technology. p. 28. ...A mock-up of the proposed “space taxi,” called the HL-20 Personnel Launch System, closely resembles a Soviet subscale spaceplane flown on four orbital missions in the 1980s...However, Piland, chief of the space systems division at the Langley Research Center, was quick to point out the Soviet test vehicle seems to have evolved from U. S. lifting-body configurations flown from 1966 to 1975—such as Northrop’s HL-10, M2-F2 and M2-F3 and Martin's X-24A and X-24B....
  7. ^ R. Dale, Reed (1997). "Wingless Flight The Lifting Body Story" (PDF). NASA. p. 180. Archived from the original (PDF) on December 18, 2014. ...The NASA lifting-body program has been well documented in about 100 technical reports on the program's 222 flights and 20,000 hours of wind-tunnel tests. Many of these publications are unclassified. The Soviet Union purchased copies of these reports from NASA Headquarters in Washington, D.C., then designed its own lifting body. In 1982, the Soviets flight-tested an unpiloted, 10-foot-long, subscale version of their lifting body, the BOR-4, including a maneuvering re-entry over the Indian Ocean from space orbit. The flight test of the BOR-4 closely resembled that of our PRIME (X-23) vehicle in 1966...
  8. ^ a b Frank Morring, Jr (February 19, 2010). "Sierra Nevada Building On NASA Design". Aviation Week.[permanent dead link]
  9. ^ a b c Rosenberg, Zach (January 30, 2013). "Lockheed to build second Dream Chaser airframe for Sierra Nevada". Flightglobal. Sutton, Surrey, UK. Archived from the original on January 7, 2014. Retrieved March 25, 2013.
  10. ^ a b Dean, James (January 30, 2013). "Sierra Nevada's Dream Chaser will get Lockheed Martin's help". Florida Today. Melbourne, Florida. Archived from the original on February 17, 2013. Retrieved February 11, 2013.
  11. ^ a b Klingler, Dave (September 6, 2012). "50 years to orbit: Dream Chaser's crazy Cold War backstory: The reusable mini-spaceplane is back from the dead—again—and prepping for space". ars Technical. Boston: Conde Nast. p. 3. Archived from the original on November 4, 2013. Retrieved September 7, 2012.
  12. ^ Doug Messier (May 24, 2014). "Virgin Galactic Hails RocketMotorTwo Milestone". ParabolicArc.
  13. ^ Messier, Doug (August 19, 2014). "SNC Abandons Own Hybrid Motors on Dream Chaser". Parabolic Arc. Retrieved March 26, 2016.
  14. ^ "NASA Deputy Administrator Lori Garver touts Colorado's role". Youtube.com. February 5, 2011. Retrieved August 29, 2012.
  15. ^ a b c d Sirangelo, Mark (August 2011). "NewSpace 2011: Sierra Nevada Corporation". Spacevidcast. Retrieved August 16, 2011. Sirangelo, Mark (August 24, 2014). "Flight Plans and Crews for Commercial Dream Chaser's First Flights: One-on-One Interview With SNC VP Mark Sirangelo (Part 3)". AmericaSpace.
  16. ^ "Moving Forward: Commercial Crew Development Building the Next Era in Spaceflight" (PDF). Rendezvous: Where Today Meets Tomorrow. 4 (2): 10–15. Summer 2010. Archived (PDF) from the original on May 10, 2013. Retrieved January 6, 2014.
  17. ^ a b "The Space Show : Mark Sirangelo interview". David Livingston. January 4, 2012. Retrieved January 7, 2012.
  18. ^ "Tile Shop Prepping Heat Shields for Future Flights". blogs.nasa.gov. Retrieved November 10, 2018.
  19. ^ Toughened Uni-piece Fibrous Reinforced Oxidation-Resistant Composite (TUFROC) backgrounder, NASA, 14 July 2015, accessed 23 November 2018.
  20. ^ "Sierra Nevada Hopes Dream Chaser Finds "Sweet Spot" of ISS Cargo Competition". SpaceNews. March 18, 2015. Retrieved February 20, 2016.
  21. ^ Jeff Foust (March 13, 2015). "Lockheed Martin Pitches Reusable Tug for Space Station Resupply". Space News.
  22. ^ Jeff Foust (March 17, 2015). "Sierra Nevada Hopes Dream Chaser Finds "Sweet Spot" of ISS Cargo Competition". Space News.
  23. ^ "SNC Selects ULA for Dream Chaser® Spacecraft Launches: NASA Missions to Begin in 2021". United Launch Alliance. August 14, 2019. Retrieved August 14, 2019.
  24. ^ Klingler, Dave (September 6, 2012). "50 years to orbit: Dream Chaser's crazy Cold War backstory: The reusable mini-spaceplane is back from the dead—again—and prepping for space". ars Technical. Boston: Conde Nast. p. 2. Archived from the original on January 4, 2014. Retrieved September 7, 2012.
  25. ^ Mewhinney, Michael. "NASA, SPACEDEV TO COLLABORATE ON FUTURE SPACE TRANSPORTATION". NASA Ames Research Center. NASA Ames Research Center. Retrieved January 15, 2016.
  26. ^ "SpaceDev and United Launch Alliance to Explore Launching the Dream Chaser(TM) Space Vehicle on an Atlas V Launch Vehicle" (Press release). Poway, California: SpaceDev. Market Wire. April 10, 2007. Archived from the original on January 6, 2014. Retrieved January 6, 2014.
  27. ^ "NASA Signs Commercial Space Transportation Agreements". NASA. June 18, 2007. Retrieved August 16, 2011.
  28. ^ Fikes, Bradley J. (October 21, 2008). "SpaceDev agrees to be acquired". U-T San Diego. Archived from the original on January 7, 2014. Retrieved January 6, 2014.
  29. ^ "SNC receives largest award of NASA's CCDev Competitive Contract". SNC. February 1, 2010. Archived from the original on February 7, 2010.
  30. ^ "Text of Space Act Agreement" (PDF).
  31. ^ "Commercial Crew: Sierra Nevada". NASA. Retrieved July 25, 2012.
  32. ^ "Dream Chaser Model Drops in at NASA Dryden". NASA. January 31, 2017.
  33. ^ Chang, Kenneth (February 1, 2011). "Businesses Take Flight, With Help From NASA". New York Times. p. D1. Archived from the original on August 9, 2014. Retrieved August 29, 2012.
  34. ^ "Sierra Nevada Space Systems Adds Key Former Nasa Leaders to Its Dream Chaser Orbital Space Vehicle Team" (Press release). Louisville, Colorado. July 5, 2011. Archived from the original on January 6, 2014. Retrieved January 6, 2014.
  35. ^ Dean, James. "NASA awards $270 million for commercial crew efforts" Archived April 19, 2011, at the Wayback Machine. space.com, April 18, 2011.
  36. ^ "Sierra nevada corporation's dream chaser space system passes preliminary design review". SNC Release. June 6, 2012. Archived from the original on August 13, 2012.
  37. ^ "Sierra nevada corporation begins flight test program of the dream chaser orbital crew vehicle". SNC Release. May 30, 2012. Archived from the original on August 13, 2012.
  38. ^ "Sierra Nevada Corporation's Space Systems Delivers the Dream Chaser® First Flight Test Vehicle Structure, Completing a Major Milestone for NASA's Commercial Crew Program" (Press release). Archived from the original on April 8, 2013.
  39. ^ "Sierra Nevada's Dream Chaser spacecraft tested at Broomfield airport". dailycamera.com. May 29, 2012. Archived from the original on May 31, 2012. Retrieved May 29, 2012.
  40. ^ Lindsey, Clark (May 14, 2013). "More about SNC preparations for drop tests of Dream Chaser prototype". NewSpace Watch. Retrieved May 14, 2013.
  41. ^ a b Bergin, Chris (May 12, 2013). "Dream Chaser ETA heads to Dryden for drop tests". NasaSpaceFlight.com. Archived from the original on December 16, 2013. Retrieved May 14, 2013.
  42. ^ Wall, Mike (August 26, 2013). "Dream Chaser space plane dangles from helicopter for second flight test". NBC News. New York. Archived from the original on January 8, 2014. Retrieved January 6, 2014.
  43. ^ a b "SNC and NASA Langley announce Five Years of Partnership". Archived from the original on July 31, 2012.
  44. ^ a b "Sierra Nevada Corporation Announces Successful Completion of Dream Chaser Cew Vehicle Nose Gear Landing Test". SNC. Archived from the original on August 7, 2012. Retrieved August 15, 2012.
  45. ^ a b "Sierra Nevada Completes Dream Chaser Safety Review". May 10, 2013. Retrieved May 15, 2013.
  46. ^ "Boeing, SpaceX and Sierra Nevada Win CCiCAP Awards". spacenews.com, August 3, 2012.
  47. ^ Bolden, Jay (March 13, 2013). "NASA Astronaut Lee Archambault Leaving Agency". NASA. Retrieved March 25, 2013.
  48. ^ "NASA Astronaut Lee Archambault Joins Sierra Nevada as Test Pilot". March 13, 2013. Retrieved March 25, 2013.
  49. ^ Bergin, Chris (October 26, 2013). "Dream Chaser suffers landing gear failure after first flight". NASA Spaceflight. Archived from the original on February 28, 2014. Retrieved January 6, 2014.
  50. ^ Harwood, William (October 29, 2013). "Sierra Nevada investigates Dream Chaser landing mishap". CBS News. New York. Archived from the original on January 6, 2014. Retrieved January 6, 2014.
  51. ^ David, Leonard (October 29, 2013). "Private Dream Chaser Space Plane Skids Off Runway After Milestone Test Flight (Video)". Space.com. New York. Archived from the original on January 30, 2014. Retrieved January 6, 2014.
  52. ^ a b "Dream Chaser mini-shuttle given 2016 launch date". BBC News. January 24, 2014.
  53. ^ "Dream Chaser passes Wind Tunnel tests for CCiCap Milestone". NASASpaceflight.com. May 19, 2014. Retrieved January 2, 2015.
  54. ^ "First Piece of Private Dream Chaser Space Plane Unveiled". Space.com. August 6, 2014.
  55. ^ Schierholz, Stephanie; Martin, Stephanie (September 16, 2014). "NASA Chooses American Companies to Transport U.S. Astronauts to International Space Station". www.nasa.gov. Retrieved September 17, 2014.
  56. ^ Norris, Guy. "Why NASA Rejected Sierra Nevada's Commercial Crew Vehicle" Aviation Week & Space Technology, October 11, 2014. Accessed: 2014-10-13. Archived on October 13, 2014
  57. ^ Keeney, Laura (October 3, 2014). "So Sierra Nevada protested NASA space-taxi contract, but what's next?". Denver Post. Retrieved October 5, 2014.
  58. ^ Browne, Clayton (October 22, 2014). "NASA Wins; Boeing and Space X Shuttle Contracts Ruled Valid". ValueWalk. Retrieved January 15, 2016.
  59. ^ "Sierra Nevada Corporation Introduces Dream Chaser Global Project Spaceflight Program Sept. 30". SpaceRef. December 29, 2014. Retrieved September 29, 2014.
  60. ^ "Sierra Nevada completes Dream Chaser's milestone 15a for prior phase of Commercial Crew". Spaceflight Insider. December 3, 2014. Retrieved December 3, 2014.
  61. ^ "SNC Tests Dream Chaser Propulsion System". NASA Blog blogs.nasa.gov. December 2, 2014. Retrieved December 2, 2014.
  62. ^ Messier, Doug (December 23, 2014). "Sierra Nevada Alleges Boeing Benefitted From Commercial Crew Criteria Changes". Parabolic Arc. Retrieved December 25, 2014.
  63. ^ Davenport, Christian. "GAO denies Sierra Nevada's legal challenge to NASA space contract". Washington Post. Retrieved January 5, 2015.
  64. ^ Christian Davenport (February 13, 2015). "Grounded: Left behind in the contracting race to restore Americans to space". The Washington Post.
  65. ^ "NASA Awards International Space Station Cargo Transport Contracts". NASA News. January 12, 2016. Retrieved January 15, 2016.
  66. ^ Dan Leone (January 24, 2015). "Weather Sat, CRS-2 Top U.S. Civil Space Procurement Agenda for 2015". SpaceNews.com.
  67. ^ "Dream Chaser preps for 2nd free-flight test and first orbital test". Space Daily. October 9, 2015.
  68. ^ "Dream Chaser still fighting for her place in space". www.nasaspaceflight.com. October 6, 2015.
  69. ^ Kenneth Chang (November 11, 2017). "Dream Chaser Space Plane Aces Glide Test - The New York Times". The New York Times. Retrieved November 15, 2017.
  70. ^ "Dream Chaser through critical landing test, prepares for orbital flights". nasaspaceflight.com. November 24, 2017. Retrieved January 28, 2019.
  71. ^ Sampson, Ben (March 27, 2019). "Dream Chaser spacecraft passes testing milestone". Aerospace Testing International. Retrieved August 14, 2019.
  72. ^ "Dream Chaser® Spacecraft Passes Another NASA Milestone". Sierra Nevada Corporation (Press release). March 21, 2019. Retrieved August 14, 2019.
  73. ^ Messier, Doug (December 16, 2013). "German Space Agency Funds Study on Uses of Sierra Nevada's Dream Chaser". Parabolic Arc. Mojave, California. Archived from the original on December 16, 2013. Retrieved December 16, 2013.
  74. ^ Clark, Stephen (January 8, 2014). "Europe eyes cooperation on Dream Chaser space plane". Spaceflight Now. Archived from the original on January 9, 2014. Retrieved January 9, 2014.
  75. ^ "Sierra Nevada Corporation to Introduce Dream Chaser® Global Project Spaceflight Program Sept. 30". SNC. September 29, 2014.
  76. ^ "Sierra Nevada Corporation to Present Progress on Evaluating Dream Chaser Landing at Public Use Airports". WFXS FOX55 WAUSAU. November 5, 2014. Archived from the original on November 7, 2014. Retrieved November 1, 2014.
  77. ^ "Challenges and Opportunities Related to Landing the Dream Chaser® Commercial Reusable Space Vehicle at a Public-Use Airport". ERAU Scholarly Commons. November 5, 2014. Retrieved November 1, 2014.
  78. ^ Completion of the initial DC4EU study (March 2, 2015). "http://www.sncorp.com/AboutUs/NewsDetails/749"
  79. ^ a b de Selding, Peter B. (April 17, 2015). "DLR Renews Cooperation with SNC on Dream Chaser". Space News. Retrieved April 21, 2015.
  80. ^ Robin Seemangal (October 3, 2016). "Dream Chaser: The Spacecraft That Will Transform Humanity's Access to Space". The Observer (New York).

External links[edit]