Misplaced Pages

Dream Chaser

Sierra Space Dream Chaser at NASA’s Neil Armstrong Test Facility in 2024
Manufacturer	Sierra Space
Country of origin	United States
Operator	NASA
Applications	International Space Station (ISS) resupply
Specifications
Spacecraft type	Robotic cargo vehicle version, also Crewed orbital spaceplane version
Payload capacity	5,000 kg (11,000 lb) pressurized, 500 kg (1,100 lb) unpressurized
Crew capacity	0 (cargo) 3–7 (crew)
Regime	LEO
Production
Status	Active
Built	3
Launched	0 (4 atmospheric tests)
Operational	1
Related spacecraft
Derived from	HL-20 Personnel Launch System
Launch vehicle	Vulcan Centaur

Dream Chaser is an American reusable lifting-body spaceplane developed by Sierra Space. Originally intended as a crewed vehicle, the Dream Chaser Space System is set to be produced after the Dream Chaser Cargo System cargo variant is operational. The crewed variant is planned to carry up to seven people and cargo to and from low Earth orbit. Sierra plans to manufacture a fleet of the spaceplane.

The Dream Chaser was originally started in 2004 as a project of SpaceDev, a company that was later acquired by the Sierra Nevada Corporation (SNC) in 2008. In April 2021 the project was taken over by the Sierra Space Corporation (SSC), spun off from the Sierra Nevada Corporation as its own fully independent company.

The cargo Dream Chaser is designed to resupply the International Space Station with both pressurized and unpressurized cargo. It is intended to be launched vertically on the Vulcan Centaur rocket and autonomously land horizontally on conventional runways. A proposed version to be operated by European Space Agency (ESA) would launch on an Arianespace vehicle.

The Dream Chaser concept and design is a descendant of NASA's HL-20 Personnel Launch System.

Spacecraft

The Dream Chaser spaceplane is designed to be launched on the top of a typical rocket and land like an airplane on a runway. The design has heritage going back decades. Currently, the Dream Chaser will resupply the ISS with cargo. Per the company's website, a crew version is planned for a later date.

Sierra Space is currently contracted under CRS-2 to perform resupply missions to the ISS over the next few years.

Propulsion

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, the SSC's predecessor, the SNC was also developing a similar hybrid rocket for Virgin Galactic's SpaceShipTwo. In May 2014, SNC involvement in the SpaceShipTwo program ended.

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 unit would be a pressure-fed three-mode engine. At low- and mid-power regimes it uses monopropellant fuel – hydrogen peroxide – and in high-power demand, the engine adds injection of RP-1 fuel. This increased thrust will be useful to shorten the de-orbit burn duration of the Dream Chaser.

Thermal protection system

Its thermal protection system (TPS) is made up of silica-based tiles (for most of the belly and upper portion of the heat shield), and a new composite material called Toughened Unipiece Fibrous Reusable Oxidation Resistant Ceramic (TUFROC) to cover the nose and leading edges.

Shooting Star module

In 2019, it was announced that an expendable Shooting Star cargo module would be part of the Dream Chaser cargo system for CRS-2 flights. The module is a 15-foot-long (4.6 m) attachment to Dream Chaser that will allow the spacecraft to carry an additional 10,000 pounds (4,500 kg) of pressurized and unpressurized cargo to ISS. The module supports disposal of unwanted cargo by burning up upon re-entry.

In addition to carrying cargo, the Shooting Star module includes solar panels that supply up to 6 kW of electrical power. It also supplies active and passive thermal management; provides Dream Chaser translation and rotation capability via six mounted thrusters; and supports berthing or docking (in different configurations) to the ISS. Access from ISS to Dream Chaser will involve crew passing through Shooting Star (which supports a shirt-sleeve environment) and through a hatch that separates Shooting Star from Dream Chaser. Sierra Nevada says the module is capable of additional types of missions in LEO or to cis-lunar destinations; they have developed a free-flying variant with additional capabilities.

In July 2020, Sierra Nevada announced a contract with the Defense Innovation Unit (DIU) to use its Shooting Star expendable cargo vehicle as a possible commercial solution for a high-powered uncrewed orbital outpost.

Technology partners

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

• Aerojet – reaction control system technology
• AdamWorks – composites
• Charles Stark Draper Laboratory – guidance, navigation, and control
• Lockheed Martin – airframe construction and human rating of the spaceplane
• MDA – systems engineering
• University of Colorado – human-rating

History

The Dream Chaser design is derived from NASA's HL-20 Personnel Launch System spaceplane concept, 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, and Martin X-23 PRIME.

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.

The Dream Chaser was publicly announced on September 20, 2004. 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. In June 2007, SpaceDev signed a Space Act agreement with NASA.

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

CCDev phase 1

On February 1, 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. SNC completed the four planned milestones on time, including hybrid rocket test fires and the preliminary structure design. Further initial Dream Chaser tests included the drop test of a 15% scaled version at the NASA Dryden Flight Research Center.

CCDev phase 2

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. On 18 April 2011, NASA awarded $80 million to Sierra Nevada Corporation for Dream Chaser. 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).

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."

On May 29, 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. 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. A second captive carry flight test was completed on August 22, 2013.

On June 12, 2012, SNC announced the commemoration of its fifth year as a NASA Langley partner in the design and development of Dream Chaser. 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.

On July 11, 2012, SNC announced that it successfully completed testing of the nose landing gear for Dream Chaser. 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. 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. 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.

CCiCap

On August 3, 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. On January 30, 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.

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.

On March 13, 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.

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. 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.

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.

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.

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

CCtCap

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

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

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

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. 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.

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."

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."

CRS-2 selection

In December 2014, Sierra Nevada proposed Dream Chaser for CRS-2 consideration. 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. The cargo spacecraft will fly alongside spacecraft from the existing CRS-1 contract holders SpaceX and Northrop Grumman Innovation Systems.

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.

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

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

In March 2019, completion of NASA's Integrated Review Milestone 5 (IR5) confirmed that development was still on schedule. In August 2019, SNC announced the first ISS flight of the Dream Chaser, known as SNC Demo-1, was planned for 2021. However, on November 17, 2020, SNC announced it would be delayed until early 2022.

In April 2021 SNC spun off its Dream Chaser division, creating the fully independent Sierra Space Corporation, which assumed responsibility for the further development of the Dream Chaser space vehicle system. In May 2022, it was announced by the deputy manager of ISS, Dana Weigel, that the mission was scheduled for February 2023. In May 2024, it was announced that Dream Chaser Tenacity completed initial flight testing and was headed next to Kennedy Space Center to prepare for launch. It arrived later that month for launch preparation. The Vulcan Centaur to be used for the launch arrived to KSC in late June 2024. However, the Orlando Sentinel reports, June 26, "Dream Chaser dropped from next Vulcan launch as ULA targets national security certification". The mission has since been delayed to no earlier than May 2025.

Variants

Crewed version

The originally planned Dream Chaser Space System is a human-rated version designed to carry from three to seven people and cargo to orbital destinations such as the International Space Station. It was to have a built-in launch escape system and could fly autonomously if needed. Although it could use any suitable launch vehicle, it was planned to be launched on a human-rated Atlas V N12 rocket. The vehicle will 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. Its reaction control system thrusters burned ethanol-based fuel, 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.

As of 2020, the Sierra Nevada Corporation said it still planned to produce a crewed version of the spacecraft within the next 5 years. The company said it "never stopped working" on the crewed version and fully intended to launch it after the cargo version, and is still committed to the crewed version as of 2021.

In November 2021, Sierra Space Corporation reported that it received a $1.4 billion investment in Series A funding, which it would use to develop a crewed version of Dream Chaser and fly astronauts by 2025. On October 25, 2021, Blue Origin and Sierra Space, released their plan for a commercial space station. The station, called Orbital Reef, is intended as a "mixed-use business park". Sierra Space Corporation's Dream Chaser was chosen as one of the commercial spacecraft to transport commercial crew to and from the space station, along with Boeing's Starliner.

CRS-2 cargo version

The cargo version of the SSC Dream Chaser is called the Dream Chaser Cargo System (DCCS) and after development is completed, 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.

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 the Crewed 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 the (retired) Ariane 5 as well as the (soon to be retired) Atlas V. An expendable cargo module will launch attached to the back 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. The expendable cargo module is called "Shooting Star".

On August 14, 2019, it was announced that all six Dream Chaser CRS-2 flights would be carried into orbit by ULA's Vulcan launch vehicle, with the first Dream Chaser flight being the second Vulcan flight in late 2021. However, on February 9, 2022, Ken Shields, Sierra Space's Director of Commercial Market Development, announced that the first flight would be pushed to January 2023. The launch has been further delayed; as of October 2024, it is scheduled for no earlier than May 2025.

National Security version

On November 19, 2021, Sierra Space announced that it is considering a third Dream Chaser version specialized for National Security missions, though it declined to comment on what the differences compared with other versions would be.

Dream Chaser Global Project

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.

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 from the Guiana Space Centre, 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. The Ariane 5 launch vehicle was designed from its inception to be crew rated, in order to launch the Hermes Spaceplane, an ESA crewed vehicle which was proposed in the 1980s and 1990s, but was cancelled.

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 was a privately arranged commercial agreement, and was funded directly by Sierra Nevada and was not a part of any existing NASA contract.

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.

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

Dream Chaser for European Utilization

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. 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. The cooperation was renewed in April 2015 for an additional two years.

United Nations

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, and carry up to 35 payloads. The United States will pay for the mission and provide all support facilities.

List of vehicles

Missions

A demonstration and six missions are currently planned to be launched from Cape Canaveral SLC-41 on Vulcan Centaur, and one more flight has been ordered to fly for the United Nations on board an Arianespace vehicle.

List includes only completed or manifested missions. NET means 'no earlier than'. Launch and landing dates and times are listed in UTC.

1. ^ A helicopter used for lifting the vehicle

See also

Spaceplanes

• RLV Technology Demonstration Programme
• Boeing X-37
• Space Rider
• NASA X-38
• Boeing X-20 Dyna-Soar
• Mikoyan-Gurevich MiG-105
• Hermes (spacecraft)
• RSC Energia Kliper

Other ISS cargo vehicles:

• Comparison of space station cargo vehicles
• Commercial Resupply Services
• Automated Transfer Vehicle
• Cygnus (spacecraft)
• SpaceX Dragon 1
• SpaceX Dragon 2
• H-II Transfer Vehicle
• Progress (spacecraft)
• Soyuz GVK

Other ISS crew vehicles:

• Commercial Crew Development
• Boeing Starliner
• SpaceX Crew Dragon
• Orel (spacecraft)
• Soyuz (spacecraft)

References

1. ^ Foust, Jeff (January 14, 2020). "Sierra Nevada explores other uses of Dream Chaser". spacenews.com. Retrieved July 11, 2020.
2. "Sierra Space Dream Chaser® Spaceplane Successfully Completes First Phase of Pre-Flight Testing". www.businesswire.com. March 7, 2024. Retrieved May 15, 2024.
3. ^ De Chiara, Giuseppe (November 19, 2012). "From HL-20 to Dream Chaser The Long story of a little spaceplane". NASASpaceflight.com. p. 26. ...Once that the HL-20 program was ceased it seems that such small spaceplane should be quickly forgotten except for a bunch of space enthusiast all over the world. The HL-20 story was no to end since in mid 2004 Jim Benson announced that the HL-20 development would be continued by his SpaceDev as Dream Chaser spacecraft. The SpaceDev was acquired by Sierra Nevada Corporation at the very end of 2008...
4. ^ "SNC Selects ULA for Dream Chaser® Spacecraft Launches". Sierra Nevada Corporation (Press release). August 14, 2019. Retrieved August 14, 2019.
5. "Dream Chaser Model Drops in at NASA Dryden" (Press release). Dryden Flight Research Center: NASA. December 17, 2010. Archived from the original on January 6, 2014. Retrieved August 29, 2012.
6. "NASA Selects Sierra Nevada Corporation's Dream Chaser Spacecraft for Commercial Resupply Services 2 Contract". Sierra Nevada Corporation (SNC). Retrieved January 28, 2024.
7. ^ 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 Technica. Boston: Conde Nast. p. 3. Archived from the original on November 4, 2013. Retrieved September 7, 2012.
8. Doug Messier (May 24, 2014). "Virgin Galactic Hails RocketMotorTwo Milestone". ParabolicArc.
9. Messier, Doug (August 19, 2014). "SNC Abandons Own Hybrid Motors on Dream Chaser". Parabolic Arc. Archived from the original on March 16, 2016. Retrieved March 26, 2016.
10. "Tile Shop Prepping Heat Shields for Future Flights". blogs.nasa.gov. 2015. Retrieved November 10, 2018.
11. "Toughened Uni-piece Fibrous Reinforced Oxidation-Resistant Composite (TUFROC)". NASA. Retrieved April 1, 2023.
12. Thompson, Amy (November 21, 2019). "Sierra Nevada Unveils 'Shooting Star' Cargo Module for Dream Chaser Space Plane". Space.com. Retrieved July 20, 2020.
13. Jelen, Bill. "Sierra Nevada Corporation Shows Off "Shooting Star" Cargo Module at KSC". We Report Space. Retrieved July 20, 2020.
14. "SNC'S "SHOOTING STAR" ARRIVES AT NASA'S KENNEDY SPACE CENTER". SNC. Sierra Nevada Corporation. Retrieved July 20, 2020.
15. "SNC Shooting Star Transport Vehicle" (PDF). SNC. Sierra Nevada Corporation. Retrieved July 20, 2020.
16. Ben, Evans (July 17, 2020). "SNC Shooting Star Wins Contract for Unmanned Orbital Outpost". AmericaSpace. Retrieved July 20, 2020.
17. ^ Frank Morring, Jr (February 19, 2010). "Sierra Nevada Building On NASA Design". Aviation Week.
18. ^ 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.
19. ^ 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.
20. "Dream Chaser: Sierra Nevada's Design for Spaceflight". space.com. November 14, 2017. Retrieved May 2, 2021.
21. 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...
22. 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...
23. 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...
24. R. Dale, Reed (1997). Wingless Flight The Lifting Body Story (PDF). NASA. p. 180. ISBN 9780160493904. 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...
25. 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.
26. Mewhinney, Michael. "NASA, SPACEDEV TO COLLABORATE ON FUTURE SPACE TRANSPORTATION". NASA Ames Research Center. Archived from the original on August 3, 2009. Retrieved January 15, 2016.
27. "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 7, 2014. Retrieved January 6, 2014.
28. "NASA Signs Commercial Space Transportation Agreements". NASA. June 18, 2007. Archived from the original on June 21, 2007. Retrieved August 16, 2011.
29. 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.
30. "SNC receives largest award of NASA's CCDev Competitive Contract". SNC. February 1, 2010. Archived from the original on February 7, 2010.
31. "Text of Space Act Agreement" (PDF). Archived from the original (PDF) on April 28, 2023. Retrieved June 28, 2010.
32. "Commercial Crew: Sierra Nevada". NASA. Archived from the original on July 23, 2012. Retrieved July 25, 2012.
33. "Dream Chaser Model Drops in at NASA Dryden". NASA. January 31, 2017. Archived from the original on June 12, 2012. Retrieved February 6, 2011.
34. 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.
35. "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.
36. Dean, James. "NASA awards $270 million for commercial crew efforts" Archived April 19, 2011, at the Wayback Machine. space.com, April 18, 2011.
37. "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.
38. "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.
39. "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.
40. "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.
41. Lindsey, Clark (May 14, 2013). "More about SNC preparations for drop tests of Dream Chaser prototype". NewSpace Watch. Retrieved May 14, 2013.
42. ^ 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.
43. 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.
44. ^ "SNC and NASA Langley announce Five Years of Partnership". Archived from the original on July 31, 2012.
45. ^ "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.
46. ^ "Sierra Nevada Completes Dream Chaser Safety Review". May 10, 2013. Archived from the original on June 10, 2013. Retrieved May 15, 2013.
47. "Boeing, SpaceX and Sierra Nevada Win CCiCAP Awards". spacenews.com, August 3, 2012.
48. Bolden, Jay (March 13, 2013). "NASA Astronaut Lee Archambault Leaving Agency". NASA. Retrieved March 25, 2013.
49. "NASA Astronaut Lee Archambault Joins Sierra Nevada as Test Pilot". March 13, 2013. Archived from the original on March 17, 2013. Retrieved March 25, 2013.
50. Bergin, Chris (October 26, 2013). "Dream Chaser suffers landing gear failure after first flight". NASASpaceflight.com. Archived from the original on February 28, 2014. Retrieved January 6, 2014.
51. 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.
52. 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.
53. ^ "Dream Chaser mini-shuttle given 2016 launch date". BBC News. January 24, 2014.
54. "Dream Chaser passes Wind Tunnel tests for CCiCap Milestone". NASASpaceflight.com. May 19, 2014. Retrieved January 2, 2015.
55. "First Piece of Private Dream Chaser Space Plane Unveiled". Space.com. August 6, 2014.
56. Schierholz, Stephanie; Martin, Stephanie (September 16, 2014). "NASA Chooses American Companies to Transport U.S. Astronauts to International Space Station". www.nasa.gov. Archived from the original on September 19, 2014. Retrieved September 17, 2014.
57. 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
58. Keeney, Laura (October 3, 2014). "So Sierra Nevada protested NASA space-taxi contract, but what's next?". Denver Post. Retrieved October 5, 2014.
59. Browne, Clayton (October 22, 2014). "NASA Wins; Boeing and Space X Shuttle Contracts Ruled Valid". ValueWalk. Retrieved January 15, 2016.
60. "Sierra Nevada Corporation Introduces Dream Chaser Global Project Spaceflight Program Sept. 30". SpaceRef. December 29, 2014. Retrieved September 29, 2014.
61. "Sierra Nevada completes Dream Chaser's milestone 15a for prior phase of Commercial Crew". Spaceflight Insider. December 3, 2014. Archived from the original on December 8, 2014. Retrieved December 3, 2014.
62. "SNC Tests Dream Chaser Propulsion System". NASA Blog blogs.nasa.gov. December 2, 2014. Retrieved December 2, 2014.
63. Messier, Doug (December 23, 2014). "Sierra Nevada Alleges Boeing Benefitted From Commercial Crew Criteria Changes". Parabolic Arc. Archived from the original on December 25, 2014. Retrieved December 25, 2014.
64. ^ Davenport, Christian. "GAO denies Sierra Nevada's legal challenge to NASA space contract". Washington Post. Archived from the original on May 13, 2015. Retrieved January 5, 2015.
65. Christian Davenport (February 13, 2015). "Grounded: Left behind in the contracting race to restore Americans to space". The Washington Post.
66. "NASA Awards International Space Station Cargo Transport Contracts". NASA News. January 12, 2016. Retrieved January 15, 2016.
67. Dan Leone (January 24, 2015). "Weather Sat, CRS-2 Top U.S. Civil Space Procurement Agenda for 2015". SpaceNews.com.
68. "Dream Chaser preps for 2nd free-flight test and first orbital test". Space Daily. October 9, 2015.
69. Bergin, Chris (October 6, 2015). "Dream Chaser still fighting for her place in space". NASASpaceflight.com. Retrieved April 7, 2021.
70. Kenneth Chang (November 11, 2017). "Dream Chaser Space Plane Aces Glide Test - The New York Times". The New York Times. Retrieved November 15, 2017.
71. "Dream Chaser through critical landing test, prepares for orbital flights". NASASpaceflight.com. November 24, 2017. Retrieved January 28, 2019.
72. Sampson, Ben (March 27, 2019). "Dream Chaser spacecraft passes testing milestone". Aerospace Testing International. Retrieved August 14, 2019.
73. "Dream Chaser® Spacecraft Passes Another NASA Milestone". Sierra Nevada Corporation (Press release). March 21, 2019. Retrieved August 14, 2019.
74. Foust, Jeff (November 18, 2020). "First Dream Chaser mission slips to 2022". spacenews.com. Retrieved April 7, 2021.
75. Michael Sheetz (May 17, 2022). "Weigel: The second Vulcan flight, carrying the first @SierraSpaceCo cargo Dream Chaser to the ISS, is currently scheduled for February 2023. "We'll be ready when they're ready."" (Tweet) – via Twitter.
76. Gamillo, Elizabeth (May 9, 2024). "Dream Chaser spaceplane completes tests at NASA's Neil Armstrong facility". Astronomy Magazine. Retrieved May 10, 2024.
77. "NASA, Sierra Space Deliver Dream Chaser to Florida for Launch Preparation - NASA". May 20, 2024. Retrieved May 20, 2024.
78. ^ Garcia, Mark (October 15, 2024). "Crew-8 Awaits Splashdown; Expedition 72 Stays Focused on Science". NASA. Retrieved October 16, 2024. The first flight of Sierra Space's Dream Chaser to the International Space Station is now scheduled for no earlier than May 2025 will carry cargo to the orbiting laboratory and stay on board for approximately 45 days on its first mission.
79. "NASA Deputy Administrator Lori Garver touts Colorado's role". Youtube.com. February 5, 2011. Retrieved August 29, 2012.
80. ^ 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.
81. "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.
82. ^ "The Space Show : Mark Sirangelo interview". David Livingston. January 4, 2012. Retrieved January 7, 2012.
83. "DREAM CHASER ON TRACK FOR 2021 CARGO MISSION, CREW WITHIN 5 YEARS". spacepolicy.com. Retrieved July 11, 2020.
84. "Sierra Nevada Corporation to spin off space division". spacenews.com. April 14, 2021. Retrieved April 22, 2021.
85. "With a huge infusion of cash, Sierra Space hopes to get its Dream Chaser spaceplane and space station off the ground". washingtonpost.cim. Retrieved November 21, 2021.
86. Davenport, Justin (October 27, 2021). "Blue Origin, Sierra Space, and Boeing announce Orbital Reef". NASASpaceflight.com. Retrieved November 30, 2021.
87. Chappell, Bill (October 25, 2021). "Blue Origin says it will build an orbiting mixed-use business park in space". NPR. Retrieved November 30, 2021.
88. Grush, Loren (October 25, 2021). "Blue Origin reveals plans for future commercial space station called Orbital Reef". The Verge. Retrieved November 29, 2021.
89. "Sierra Nevada Hopes Dream Chaser Finds "Sweet Spot" of ISS Cargo Competition". SpaceNews. March 18, 2015. Retrieved February 20, 2016.
90. Jeff Foust (March 13, 2015). "Lockheed Martin Pitches Reusable Tug for Space Station Resupply". Space News.
91. Jeff Foust (March 17, 2015). "Sierra Nevada Hopes Dream Chaser Finds "Sweet Spot" of ISS Cargo Competition". Space News.
92. "SNC Selects ULA for Dream Chaser® Spacecraft Launches: NASA Missions to Begin in 2021". United Launch Alliance. August 14, 2019. Retrieved August 14, 2019.
93. "Interview with Sierra Space: Dream Chaser launch set for January 2023, Orbital Reef space station, manufacturing in space, & more". Space Explored. February 9, 2022. Retrieved February 23, 2022.
94. "Sierra Space raises $1.4 billion". SpaceNews. November 19, 2021. Retrieved January 5, 2022.
95. 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.
96. 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.
97. "Sierra Nevada Corporation to Introduce Dream Chaser® Global Project Spaceflight Program Sept. 30". SNC. September 29, 2014.
98. "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.
99. "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.
100. Completion of the initial DC4EU study (March 2, 2015). "http://www.sncorp.com/AboutUs/NewsDetails/749"
101. ^ de Selding, Peter B. (April 17, 2015). "DLR Renews Cooperation with SNC on Dream Chaser". Space News. Retrieved April 21, 2015.
102. ^ Pesce, Ottavia; Schwandt, Kimberly (October 22, 2019). "UNOOSA and Sierra Nevada Corporation announce Call for Interest to provide landing site for Dream Chaser spacecraft mission carrying experiments from UN Member States". Sierra Nevada Corporation (Press release). Retrieved February 26, 2020.
103. Seemangal, Robin (October 3, 2016). "Dream Chaser: The Spacecraft That Will Transform Humanity's Access to Space". The Observer (New York).
104. @SierraSpaceCo (May 20, 2022). "@DutchSpace DC-101" (Tweet) – via Twitter.
105. "Sierra Space completes first Dream Chaser". spacenews.com. November 6, 2023. Retrieved November 6, 2023.
106. David, Leonard (November 8, 2024). "Sierra Space expands spaceplane fleet with in-house mission control". SpaceNews. Retrieved November 9, 2024.
107. OIG Staff (April 26, 2018). Audit of Commercial Resupply Services to the International Space Center (PDF). NASA Office of Inspector General (Report). Vol. IG-18-016. NASA. pp. 27–28. Retrieved December 11, 2023. In August 2017, ISS Program officials said Sierra was considering building a second Dream Chaser to be completed by 2021, but no decision had been made as of October 2017. In the event of a failure, Sierra officials told us in June 2017 that a second spacecraft could be built from spare parts without additional costs to NASA. This article incorporates text from this source, which is in the public domain.
108. Sawyer Rosenstein (February 8, 2024). "Dream Chaser undergoes NASA testing ahead of first flight". NASASpaceflight.com.

External links

• Sierra Space web site
• Sierra Space Dream Chaser page
• SpaceDev web site
• United Launch Alliance web site
• CG rendering of Dream Chaser servicing ISS
• Video animation – SpaceDev International Lunar Observatory Human Servicing Mission concept

v t e Cargo spacecraft
Active	Cygnus Cargo Dragon 2 Progress Tianzhou
In development	Blue Moon Dragon XL Dream Chaser HTV-X Soyuz GVK Starship Argo
Retired	ATV Dragon 1 TKS HTV (Kounotori)
Proposed	TGK PG
Cancelled	Andrews Cargo Module ARCTUS Jupiter Kistler K-1 Parom S-550 OMV
Comparison of space station cargo vehicles

• Spaceplanes
• Private spaceflight
• Proposed spacecraft
• Aircraft first flown in 2013
• Lifting bodies
• Sierra Nevada Corporation aircraft
• American spacecraft
• Reusable spacecraft
• Proposed crewed spacecraft