The debut of Sierra Space’s cargo space plane Dream Chaser has delayed again and will no longer see a docking with the International Space Station. In a statement Thursday afternoon, NASA said the space agency and Sierra Space had agreed to a major modification of their space station resupply contract.
The space plane is now scheduled to launch on its inaugural flight no earlier than late 2026. Additionally, instead of docking to the ISS, the vehicle named Tenacity will now conduct a free-flyer mission.
NASA said under the contract revsion it is “no longer obligated for a specific number of resupply missions.” The original Commercial Resupply Services-2 (CRS-2) contract specified a minimum of seven flights to the ISS, with four missions awarded as part of a firm-fixed price task order “based on the needs of the space station.”
“Development of new space transportation systems is difficult and can take longer than what’s originally planned,” said Dana Weigel, manager of NASA’s International Space Station Program. “The ability to perform a flight demonstration can be a key enabler in a spacecraft’s development and readiness, as well as offering greater flexibility for NASA and Sierra Space.
“As NASA and its partners look toward space station deorbit in 2030, this mutually agreed to decision enables testing and verification to continue on Dream Chaser, as well as demonstrating the capabilities of the spaceplane for future resupply missions in low Earth orbit.”
Back in 2016, Sierra Nevada Corporation, parent company to Sierra Space, was awarded a CRS-2 contract alongside Northrop Grumman and SpaceX for a maximum potential value of $14 billion from 2016 through 2024.
In November 2024, NASA extended the CRS-2 contract with all three providers with mission award period now running through December 31, 2030. That would take the cargo flights through the approximate end of life for the space station.
Currently the SpX-33 and NG-23 missions are servicing the ISS with the Dragon and Cygnus spacecraft set to depart in December and March respectively.
Spaceflight Now reached out to NASA to ask how soon Sierra Space could reasonably be awarded a mission to the ISS, assuming a nominal free-flyer mission next year. An agency spokesperson said that’s still up in the air.
“Following a successful orbital demonstration mission and certification, NASA may order flights from Sierra Space as part of the agency’s Commercial Resupply Services-2 contract based on the agency’s needs,” a NASA spokesperson said.
Meanwhile, Sierra Space said in a press release that this free-flyer mission “is expected to prove the technology and deliver critical data to NASA” and also “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.”
Sierra Space is one of the primary partners, alongside Blue Origin, that are developing a commercial space station called Orbital Reef. Sierra Space would use Dream Chaser as a method of cargo transport and also provide its inflatable LIFE (Large Integrated Flexible Environment) Habitat modules.
Back in April 2025, NASA said Orbital Reef completed human-in-the-loop testing, demonstrating some daily operations inside a mockup of the commercial space station.
Sierra Space put a positive spin on the changes to its contract with NASA.
“Dream Chaser represents the future of versatile space transportation and mission flexibility,” Sierra SpaceExecutive Chair Faith Ozmen said in the company’s press release. “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.
“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.”
What happened to Dream Chaser?
The Dream Chaser space plane was originally imagined as a crewed vehicle that could fly as part of NASA’s Commercial Crew Program. Ultimately, NASA down-selected to Boeing’s CST-100 Starliner and SpaceX’s Crew Dragon, leaving Sierra Space to pivot on its plans.
Since then the cargo version of the vehicle has been in the works. For years, it was slated to be the payload on the second certification (Cert-2) flight of United Launch Alliance’s Vulcan rocket. ULA President and CEO Tory Bruno said last year that they waited as long as they could in the hopes of launching Dream Chaser on the Cert-2 mission, which ultimately resulted in ULA flying without a payload on that mission.
Back in February 2024, members of the media were invited to NASA’s Neil A. Armstrong Test Facility in Sandusky, Ohio, to see the Dream Chaser space plane integrated with the Shooting Star cargo module. Leadership with NASA and Sierra Space touted the capabilities of the vehicle, looking towards it first launch.
“We are coming out of years of development, years of hard work, years of resolving really tough engineering challenges that come from revolutionizing the way we do things,” said Tom Vice, the then CEO of Sierra Space. “And we are really excited that this year we enter orbital operations for NASA. It is a year that we change how we connect Earth and space.”
In May 2024, Tenacity arrived at the Space Systems Processing Facility (SSPF) at NASA’s Kennedy Space Center in Florida for “final testing and prelaunch processing.” Between then and now, there have been few official details about the work being done on the vehicle.
In response to questions from Spaceflight Now, Sierra Space said the following:
“Significant manufacturing milestones have been achieved for Dream Chaser, which is now entering final testing phases to meet rigorous pre-launch requirements. The vehicle has begun Electromagnetic Interference (EMI) testing—an essential step toward ensuring mission readiness and reliability. Sierra Space remains focused on completing the final phases of testing and preparation to ensure Dream Chaser’s successful first flight, planned for late 2025 and now anticipated in late 2026 due to launch vehicle availability.”
