thumb|Dream Chaser flight test vehicle in 2013
Dream Chaser is an American reusable lifting-body spaceplane developed by Sierra Space. Conceived as a crewed vehicle, it is being developed in a cargo configuration known as the Dream Chaser Cargo System for missions to the International Space Station (ISS) under NASA's Commercial Resupply Services program.
Development of Dream Chaser began in 2004 as a project of SpaceDev, which was acquired by Sierra Nevada Corporation (SNC) in 2008. and the spacecraft's initial mission in late 2026 will no longer dock at the ISS as originally planned.
The Dream Chaser’s design is derived from NASA's HL-20 Personnel Launch System, a lifting-body concept studied in the 1980s and 1990s.
Spacecraft
thumb|Dream Chaser engineering test article, being driven along the runway by a pickup truck after an atmospheric test
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 was contracted under CRS-2 to perform resupply missions to the ISS, but in a September 2025 contract change Sierra Space only needs to perform a free flight demonstration, with NASA optionally booking resupply missions.
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.
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.
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 attachment to Dream Chaser that will allow the spacecraft to carry an additional 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: 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. 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.
thumb|Dream Chaser model being tested at NASA Langley, aboard an [[Atlas V mock-up]]
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."
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,
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.
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 was subsequently delayed to no earlier than May 2025, and had still not been scheduled for a specific date as of September 2025. The spacecraft is also no longer contracted to complete seven resupply missions to the ISS.
Variants
Crewed version
thumb|upright|Artist's conception of the Dream Chaser Space System in the launch configuration of the [[Atlas V ]]
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. and is still committed to the crewed version
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, although this ultimately did not occur. 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
thumb|Artist's conception of the crewed Dream Chaser docked to [[International Space Station]]
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 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 of trash. Total uplift is planned for pressurized and unpressurized, with a downlift of 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; it is scheduled for no earlier than May 2025, and as of February 2026, the mission is targeted to launch in late 2026.
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.
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.
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
{| class="wikitable" style="font-size:90%;"
| style="text-align:left" |
|}
{| class="wikitable sortable" style="font-size:small"
! Type
! style="width:6em" | Serial
! style="width:6em" | Name
! Status
! Flights
! Time in flight
! class="unsortable" | Notes
|-
| style="background:#ff9e3d;" | Prototype
|
|Eagle
|
| 4
| data-sort-value="4" | ~5 minutes
| Engineering Test Article (ETA) used for captive carry and atmospheric drop tests
|-
| style="background:#ff9e3d;" | Prototype
|
| Ascension
|
| 0
|
| Flight Test Article (FTA) to be used for atmospheric tests
|-
| style="background:#3d9eff;" | Cargo
|
| Tenacity
|
| 0
|
| Spacecraft to be flown on SSC Demo-1 mission.
|-
| style="background:#3d9eff;" | Cargo
|
| Reverence
|
| 0
|
| Construction on hold ; company estimates 18 months of work remain.
|}
Mockups
{| class="wikitable"
|+
!Name
!Location
!Status
!Notes
|-
|Dream Chaser
|Wings Over the Rockies Air and Space Museum
|On Display
|Replica of a crewed Dream Chaser spaceplane. Originally constructed in 1990 as an HL-20 mockup prior to the program's cancellation.
|-
|Tenacity
|Kennedy Space Center Visitor Complex
|On Display
|Replica of Tenacity mated to Shooting Star module. Located in Gateway section of the complex.
|}
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.
{| class="wikitable sticky-header"
! Mission
! Spacecraft
! Launch
! Landing
! Launch vehicle
! Remarks
! Outcome
|-
! Captive Test 1
| ETA Eagle
| May 29, 2012
| May 29, 2012
| Erickson Skycrane
| 1st atmospheric test
|
|-
! Captive Test 2
| ETA Eagle
| August 22, 2013
| August 22, 2013
| Erickson Skycrane
| 2nd atmospheric test
|
|-
! Drop Test 1
| ETA Eagle
| October 26, 2013
| October 26, 2013
| Erickson Skycrane
| 1st free flight test
|
|-
! Drop Test 2
| ETA Eagle
| November 11, 2017
| November 11, 2017
| Boeing-Vertol 234
| 2nd free flight test
|
|-
! SSC Demo-1
| DC101 Tenacity
| NET Late 2026
| NET Late 2026
| Vulcan Centaur
| First orbital flight, originally an approximately 45-day ISS resupply mission, now will not visit the ISS.
|
|-
! CRS SSC-1
| DC101 Tenacity
| TBA
| TBA
| Vulcan Centaur
| 1st contracted CRS mission for NASA
|
|-
! CRS SSC-2
| DC101 Tenacity
| TBA
| TBA
| Vulcan Centaur
| 2nd contracted CRS mission for NASA
|
|-
! CRS SSC-3
| DC101 Tenacity
| TBA
| TBA
| Vulcan Centaur
| 3rd contracted CRS mission for NASA
|
|-
! CRS SSC-4
| DC102 Reverence
| TBA
| TBA
| Vulcan Centaur
| 4th contracted CRS mission for NASA
|
|-
! CRS SSC-5
|
| TBA
| TBA
| Vulcan Centaur
| 5th contracted CRS mission for NASA
|
|-
! CRS SSC-6
|
| TBA
| TBA
| Vulcan Centaur
| 6th contracted CRS mission for NASA
|
|-
! DC UNOOSA-1
|
| TBA
| TBA
| Arianespace vehicle
| To carry 35 payloads for the United Nations Office for Outer Space Affairs.
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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