NASA’s two stranded astronauts will be brought home from the International Space Station (ISS) aboard a SpaceX vehicle in February 2025. The defective Starliner spacecraft that brought them there will then return without a crew, the agency said.
The announcement was made on a press conference on Saturday (August 24) is the final nail in the coffin for Boeing’s first Starliner crew test flight, whose astronauts Butch Wilmore and Sunita “Suni” Williams have been stuck aboard the ISS since June waiting for NASA officials to assess several technical problems that arose during the Starliner’s journey into space.
The first manned test flight of the Boeing spacecraft was originally planned to last only eight days, but was hampered by numerous helium leaks and engine failures on the outbound flight, delaying the return by more than two months.
After an agency-wide review, NASA has now concluded that there are too many uncertainties to ensure the safe return of the spacecraft and its crew.
“NASA has decided that Butch and Suni will return next February on SpaceX’s Crew-9 and that Starliner will return uncrewed,” the NASA administrator said. Bill Nelson he said at a press conference on August 24. “I want you to know that Boeing has worked very hard with NASA to obtain the necessary data to make this decision. We want to better understand the root causes and understand the design improvements so that the Boeing Starliner will be an important part of our assured access to the ISS for our crew.”
Starliner launched on its first manned test flight from the Cape Canaveral Space Force Station in Florida on June 5. But shortly after entering orbit, the spacecraft experienced a series of errors – including five Helium leaks and five reaction control system (RCS) engine failures.
This forced engineers to fix the problems from the ground. Tests conducted at the Starliner facility in White Sands, New Mexico, showed that during the spacecraft’s ascent to the ISS, the Teflon seals in the five defective RCS engines probably got hot and bulged the place to obstruct the flow of fuel, according to NASA.
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A hot-burn test conducted on July 27 while the spacecraft was docked to the ISS showed that thrust was back to normal levels, but NASA engineers still feared the problem could recur during the spacecraft’s approach to Earth. They also worried that the helium leaks could disable some of the spacecraft’s Orbital Maneuvering and Attitude Control (OMAC) system thrusters, which keep the spacecraft on a safe trajectory.
“There were simply too many uncertainties in predicting the engines,” Steve Stichthe program manager of NASA’s Commercial Crew Program, said at the press conference. “If we had a way to predict exactly what the engines would do at undocking and throughout the burn and separation sequence, I think we would have acted differently.”
NASA’s new plan is to bring the astronauts home aboard a SpaceX Dragon capsule instead. The vehicle will be sent to the ISS on September 24 with members of ISS Crew-9, who will replace the current Crew-8 aboard the space station. Instead of the usual four-person Crew-9 crew, two astronauts will fly to the ISS to make room for Wilmore and Williams, who will return in February 2025.
The Starliner capsule is scheduled to undock from the ISS in early September and make a controlled, unmanned approach to Earth, NASA said.
Boeing built the Starliner capsule as part of NASA’s Commercial Crew Program, a partnership between the agency and private companies to launch astronauts into low Earth orbit after NASA’s space shuttles were retired in 2011. The company has so far built around 1.6 billion US dollars to address numerous setbacks in the Starliner’s development that call into question its long-term involvement in the NASA program.
“We remain primarily focused on crew and spacecraft safety,” Boeing said. said in a statement posted on Saturday on X. “We are executing the mission as defined by NASA and preparing the spacecraft for a safe and successful unmanned return.”
