Sierra Nevada prepares for spring landing test of Dream Chaser
Continuing on a developmental track as part of its CRS-2 contract award from NASA, the Sierra Nevada Corporation has shipped the Engineering Test Article of their Dream Chaser space plane to Edwards Air Force Base, California, ahead of a planned spring 2017 free-flight to test the vehicle’s low-atmosphere control and landing capabilities – ahead of operational flights for NASA and the United Nations in the coming years.
The return of Dream Chaser:
While Dream Chaser never really left the arena of spaceflight, its initial long-term prospects looked relatively grim following NASA’s decision not to accept it as part of the 2014 Commercial Crew Transportation Capabilities contract awards for the International Space Station (ISS).
Nonetheless, the Sierra Nevada Corporation stated that it would continue to develop Dream Chaser on its own in the initial aftermath of that decision – following a failed appeal of NASA’s decision.
This was followed closely thereafter by an extension of NASA’s Space Act Agreement (SSA) with Sierra Nevada to cooperatively continue development of Dream Chaser until March 2016 – at which point Dream Chaser would pass from a Preliminary Design to a Critical Design Review.
That SSA was then subsequently extended again to June 2017.
Extension of the SSA with NASA significantly worked to Sierra Nevada’s favor when NASA solicited bids for its Commercial Resupply Services-2 (CRS-2) contracts.
For CRS-2, Sierra Nevada submitted a proposal to use the Dream Chaser space plane in an uncrewed, cargo-only configuration.
While NASA was initially expected to award two CRS-2 contracts, the agency formally announced in January 2016 that three companies would be awarded contracts – including Sierra Nevada for Dream Chaser alongside current CRS-1 contract holders SpaceX and Orbital ATK.
With CRS-2 contract flights scheduled to begin No Earlier Than 2019, Sierra Nevada is proceeding with a final testing sequence of Dream Chaser – capitalizing on previously conducted tests of the Engineering Test Article (ETA) of the spaceplane.
This spring, one of the most visible precursors to Dream Chaser’s first spaceflight will come in the form of a free-flight test at Edwards Air Force Base, CA.
The spring 2017 free-flight will be the second free-flight test of Dream Chaser following the first which occurred on 26 October 2013.
That October 2013 test saw Dream Chaser hoisted to altitude underneath a helicopter before being released for an autonomous flight to the runway.
The 2013 test was designed to verify and validate Dream Chaser’s low-atmosphere aerodynamics, flight control surfaces, flight characteristics for approach, flare and landing, and landing systems.
Overall, the test went extremely well after Dream Chaser was released from the helicopter, with the space plane flying itself toward the ground and runway for a landing approximately one minute after release.
However, as it approached the runway, and landing gear deployment was commanded, the left landing gear failed to deploy fully, resulting in the vehicle skidding off runway 22L at Edwards.
Nonetheless, post-test recovery of Dream Chaser showed that while the craft suffered minor damage, the crew compartment was intact and all of its systems were still operational – accidentally demonstrating Dream Chaser’s robust capability to survive a landing gear out scenario at landing.
After repairs and refurbishment, in October 2015 – three months before its official selection as part of the CRS-2 contract program – the ETA Dream Chaser had its thermal protection system installed for the next phase of atmospheric flight testing.
That same month, the first orbital Dream Chaser – known as the Flight Test Article (FTA) – completed orbital cabin assembly at Lockheed Martin’s Michoud Assembly Facility in Louisiana.
Spring 2017 free-flight:
While the 2013 free-flight of Dream Chaser was deemed a success by both Sierra Nevada and NASA (despite sliding off the runway), Dream Chaser’s teams elected to repeat the ground tests in an effort to gather more data and fly Dream Chaser in a more robust flight environment, stated Phil McAlister, Director of Commercial Spaceflight Development at NASA, during a NASA Advisory Council Human Exploration and Operations committee meeting in July 2016.
The new series of tests will once again take place at Edwards Air Force Base and NASA’s Armstrong Flight Research Center and will in many ways mirror the series of tests performed in 2013.
Before Dream Chaser takes to the air, a series of ground tests will be performed on the ETA to verify the vehicle’s systems, towing ability, landing gear performance, breaking, software upgrades, and a host of improvements that have been made to the vehicle since 2013.
Once these tests are completed, Dream Chaser will be hoisted into the air for captive carry test.
Then, it will be taken to the air by helicopter and released for a one minute controlled flight through the lower atmosphere toward one of the runways at Edwards.
In many ways, these free-flight tests, while verifying the aerodynamic and flight control ability of the vehicle, will mirror the series of Approach and Landing tests conducted by NASA using the Space Shuttle Enterprise in the late 1970s.
Those tests were deemed crucial to verifying the Shuttle Orbiter’s overall aerodynamic and flight control capabilities in the crucial final minute of flight as the iconic vehicle descended unpowered toward the runway.
Now, some 40 years later, Dream Chaser will continue that vision with an upgraded series of systems that, unlike the Shuttle, allow the spacecraft to be operated completely autonomously and independently of a crew.
If these tests are successful, Sierra Nevada will continue – as they already are – to press forward with finalization of the design and build of the cargo variant of Dream Chaser.
If current funding levels and schedules hold, Sierra Nevada anticipates the first cargo Dream Chaser flight to the ISS to take place in the second half of 2019.
The current CRS-2 contracts grant Sierra Nevada, as well as SpaceX and Orbital ATK, six flights each for resupply services to and from the Station – for a total of 18 commercial cargo runs between 2019 and 2024.
Dream Chaser – not just for NASA and Station:
One of the truly unique elements of the Dream Chaser design – both in its cargo and crew configurations – is its integration, accessibility, and usefulness to organizations outside the United States.
In 2013, Sierra Nevada and OHB, a European multinational technology corporation headquartered in Bremen, Germany, began a multi-year investigation into the potential uses of Dream Chaser for a variety of crewed and uncrewed flights to Low-Earth Orbit to support microgravity science, satellite servicing, and active debris removal initiatives.
The initial investigation culminated in February 2015 with an extremely favorable opinion regarding Dream Chaser’s potential utilization by the European community.
This led to an official extension of the cooperation between Sierra Nevada and OHB – an extension that is scheduled to last until at least April 2017.
Moreover, the Dream Chaser design also caught the eye of the United Nations, which has selected Dream Chaser to perform the first UN space mission in 2021.
Specifically, the United Nations Office for Outer Space Affairs (UNOOSA) recognized Dream Chaser’s ability – through the UN system – to provide member nations that do not have access to space or space programs of their own to tap into the LEO microgravity research environment/market.
The goal of the first-of-its-kind mission is to allow United Nations member states to conduct research that cannot be done on Earth.
The planned 2021 flagship mission will be an uncrewed flight of the Dream Chaser cargo craft, is expected to last at least two weeks, and will not rendezvous with the International Space Station – making it the first independent microgravity research flight since the 2003 flight of the Space Shuttle Columbia on STS-107.
(Images: Sierra Nevada and L2 artist Nathan Koga – The full gallery of Nathan’s (SpaceX Dragon to MCT, SLS, Commercial Crew and more) L2 images can be *found here*)