NASA is downsizing its commitment to International Space Station (ISS) missions using Boeing’s Starliner CST-100.
The space agency on Monday said it and Boeing had “mutually agreed” to reduce the scope of the Commercial Crew Transportation Capability contract—awarded in 2014—from six definitive missions to four, with two options.
The first of those missions, NASA said, will be an uncrewed ISS flight intended to validate changes that engineers made following Starliner’s inaugural crew flight test (CFT), which launched to the orbital laboratory in June 2024. The mission, Starliner-1, will fly no earlier than April.
“This modification allows NASA and Boeing to focus on safely certifying the system in 2026, execute Starliner’s first crew rotation when ready, and align our ongoing flight planning for future Starliner missions based on [the ISS’s] operational needs through 2030,” Steve Stich, manager of NASA’s Commercial Crew program, said in a statement.
The CFT had been intended as the final mission before Starliner was certified for crew. But the spacecraft encountered problems almost immediately, forcing NASA to extend the planned eight-day ISS stay.
Ultimately, it returned uncrewed in September, and its passengers—NASA astronauts Butch Wilmore and Suni Williams—hitched a ride down on SpaceX’s Crew Dragon in March. SpaceX was the other recipient of NASA’s 2014 Commercial Crew Transportation Capability contract, and its Dragon is preparing for its twelfth ISS crew rotation mission in 2026.
Once human-rated, NASA expects Starliner to fly up to three crew rotation missions. Boeing in a statement said a second mission following Starliner-1 is possible in 2026.
“Boeing remains committed to supporting NASA’s goal of sustained human presence in low Earth orbit through the ongoing development and certification of the Starliner spacecraft,” a spokesperson said. “Safety remains our highest priority as we focus on the Starliner-1 mission, which incorporates our findings and learnings from previous flight tests and testing this fall.”
Why Starliner?
Boeing’s initial $4.2 billion contract award, which was later raised to $4.5 billion, called for at least one crewed test and six operational Starliner missions. SpaceX received $2.6 billion with the same expectations for its Crew Dragon.
NASA awarded the contracts amid a strategic shift as it looked to refocus its resources toward deep space missions. It sought two commercial contractors to handle routine missions to the ISS, the idea being that if one spacecraft malfunctions, the other could step in.
By outsourcing those flights to the private sector, NASA could focus on bigger priorities, such as Mars exploration. At the same time, it would reduce its reliance on Russia’s Roscosmos, whose Soyuz capsule is still used for ISS crew swaps.
The space agency has since awarded billions of dollars for nine Crew Dragon missions beyond SpaceX’s original six. Boeing has lost about $2 billion on the Starliner program due to costs exceeding its contract award, which it must pay out of pocket.
NASA in 2014 set the “goal of ending the nation’s sole reliance on Russia in 2017” by having Dragon and Starliner operational. Neither company met that timeline. But as Starliner continues to rack up delays, the scrutiny is on Boeing.
What’s Next?
Boeing is optimistic that Starliner can complete not just one but two missions in 2026. Given the spacecraft’s history, that may be ambitious.
NASA in 2015 internally predicted that the initial Starliner CFT would lift off in October 2017. But problems arose quickly. By May 2016, Boeing had shifted its CFT timeline to early 2018—the first in what would become a cascade of delays.
Starliner’s first uncrewed test flight came in 2019, and its first uncrewed trip to the ISS in 2022. That gave the space community some optimism as SpaceX entered its second year of operational Dragon missions. Ultimately, the CFT launched in June 2024.
Hours after reaching orbit, NASA and Boeing reported degraded thruster performance and a series of helium leaks within Starliner’s propulsion system. The space agency made the decision to keep the vehicle at the orbital laboratory. After a few months, it announced that a SpaceX Dragon would return the Starliner crew.
The situation garnered international attention as Wilmore and Williams reassured the public of their safety. Even President Donald Trump became involved, urging SpaceX to “go get” the astronauts, though NASA had announced its Dragon return plan months earlier.
The CFT created a public relations storm for Boeing as the company defended against claims the astronauts were “stranded” in space. More significantly for the Starliner program, it forced engineers to conduct additional ground testing—and prompted NASA to require a third uncrewed flight to validate that testing.
Boeing will have another chance to prove that Starship is human-ready in 2026. Given the time and money it has poured into the program, the outcome will undoubtedly be consequential.
