27.09.2025

NASA has modified its ISS resupply contract with Sierra Space, which builds the robotic Dream Chaser space plane.

Sierra Space's first Dream Chaser space plane, named Tenacity, is seen inside a hangar. (Image credit: Sierra Space)

The International Space Station (ISS) may never again be visited by a space plane.

NASA's space shuttle orbiters were instrumental in building the ISS, and in keeping it operational for its first decade; these reusable spacecraft ferried astronauts to and from the orbiting outpost until the fleet was fully retired in 2011. Five years later, the agency opened the door to more space plane meetups, signing a cargo deal with Sierra Space, the Colorado-based company behind the robotic Dream Chaser vehicle.

That 2016 contract awarded Sierra Space a minimum of seven ISS resupply flights with Dream Chaser and its companion cargo module, called Shooting Star. Nine years later, however, Dream Chaser has still not reached space — and its cargo deal has just been changed.

"After a thorough evaluation, NASA and Sierra Space have mutually agreed to modify the contract, as the company determined Dream Chaser development is best served by a free flight demonstration, targeted in late 2026," agency officials said in an emailed statement on Thursday (Sept. 25).

"Sierra Space will continue providing insight to NASA into the development of Dream Chaser, including through the flight demonstration," they added. "NASA will provide minimal support through the remainder of the development and the flight demonstration. As part of the modification, NASA is no longer obligated for a specific number of resupply missions; however, the agency may order Dream Chaser resupply flights to the space station from Sierra Space following a successful free flight as part of its current contract."

The timeline is getting a bit tight for possible Dream Chaser ISS missions, given the orbiting lab is scheduled to be deorbited in 2030. However, NASA is encouraging the development of commercial stations in low Earth orbit to fill the void left by the ISS' impending departure, and it's possible that Dream Chaser could visit one or more of those in the coming years.

In a different statement released on Thursday, Sierra Space (which spun off from the aerospace firm Sierra Nevada Corp. in 2021) invoked that and other potential use cases for Dream Chaser. Company officials stressed the space plane could still fly a variety of missions down the road, even if the vehicle never makes it to the ISS.

"Dream Chaser represents the future of versatile space transportation and mission flexibility," Fatih Ozmen, executive chair at Sierra Space, said in the statement.

"This transition provides unique capabilities to meet the needs of diverse mission profiles, including emerging and existential threats and national security priorities that align with our acceleration into the Defense Tech market," Ozmen added. "Together with NASA, we are seeking to preserve the exceptional potential of Dream Chaser as a national asset, ensuring its readiness for the next era of space innovation."

Two private American companies currently fly robotic resupply missions to the ISS for NASA — SpaceX, with its Dragon capsules, and Northrop Grumman, which uses a spacecraft called Cygnus. The agency also tapped SpaceX to deorbit the ISS in a controlled fashion in 2030, using a modified version of Dragon.

Quelle: SC

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DREAM CHASER SLIPS TO END OF 2026 FOR FREE-FLYER DEMO ONLY

NASA said today they are requiring Sierra Space to conduct a free flyer demonstration of the Dream Chaser spacecraft before the first cargo mission to the International Space Station. The contractual requirement that NASA buy seven cargo flights is also eliminated. Dream Chaser has yet to make a spaceflight after more than a decade of development and the demonstration flight is not even expected until the end of 2026. Sierra Space called the changes a “strategic transition.”

Sierra Space, a spin-off from Sierra Nevada Corporation, has been working on Dream Chaser for more than a decade. The company originally bid for NASA’s commercial crew program to build a human spaceflight version of the small winged vehicle. Dream Chaser resembles the space shuttle and originated at NASA in the early 1990s as studies for an HL-20 Personnel Launch System that was never built.

Sierra Space was one of the companies receiving NASA funding through the Commercial Crew Integrated Capabilities (CCiCAP) program in the early 2010s, but lost to Boeing and SpaceX for selection as one of the two Commercial Crew Transportation Capabilities (CCtCAP) awards. They protested to the Government Accountability Office, but their claims were denied.

The company decided to proceed with an uncrewed version of the vehicle instead and bid in the second round for cargo resupply of the International Space Station through the Commercial Resupply Services (CRS) program. SpaceX and Orbital ATK (now Northrop Grumman) already had CRS contracts. In 2016, Sierra Space was added as a third service provider, with plans to build the crewed version of Dream Chaser later.

Sierra Space has been reporting progress over the years. In 2020 they said cargo flights would begin in 2021 and crewed flights five years later. By 2023, the first cargo flight was said to be close at hand and expected to support NASA’s Crew 7 that was aboard the ISS from August 2023 to March 2024. None of that materialized. Last year, the United Launch Alliance (ULA) delayed the second certification launch of their new Vulcan rocket month by month expecting Dream Chaser to be ready, but finally gave up and sent Vulcan to space with only a mass demonstrator.

Little has been said about Dream Chaser since then. When asked, ULA President Tory Bruno expresses enthusiasm for  launching it when ready — Sierra Space bought six ULA Vulcan launches for Dream Chaser — and NASA has been carefully sidestepping estimates for when the first flight to the ISS will take place.

Still, today’s revelation that even a flight demonstration won’t take place for more than a year comes as a bit of surprise.

NASA said it’s requiring a free flight demonstration (not visiting the ISS) as part of Dream Chaser’s development program and will provide “minimal support” until that’s completed. In addition, they are modifying the 2016 contract, eliminating NASA’s requirement to purchase seven cargo flights. Instead it “may” order flights after the demo. The ISS is expected to be deorbited in 2030 and crews will stop flying there about a year earlier. There won’t be many opportunities for Dream Chaser to deliver cargo even if the flight demo is flawless.

NASA space station program manager Dana Weigel said this “mutually agreed to decision enables testing and validation to continue” and “demonstrating the capabilities” of Dream Chaser for future resupply missions.

Sierra Space did not reply to a request for comment by press time, but posted a photo of Dream Chaser on X (@SierraSpaceCo) with a statement confirming the first flight will be a free-flyer “targeting a launch in late 2026 to align with expected launch vehicle availability.”

In a press release, Sierra Space called it a “strategic transition” as they seek “to preserve the exceptional potential of Dream Chaser as a national asset, ensuring its readiness for the next era of space innovation.”  They added the changes aim “to provide Sierra Space with flexibility to address the nation’s most pressing National Security Space challenges, while continuing to advance Dream Chaser’s capabilities for NASA and commercial customers.”