NASA has postponed a decision on whether to return its stranded Starliner astronauts until late August, pending a “major discussion” about the spacecraft’s readiness to fly, agency officials said.
Originally planned to last only eight days, numerous leaks and other technical problems with Boeing’s Starliner spacecraft en route to the International Space Station (ISS) in June delayed the planned return flight by more than two months and left the two astronauts Butch Wilmore and Sunita Williams stranded in space.
While engineers continue to collect and discuss test results on the spacecraft’s problems, NASA leadership is still pondering whether to send the two astronauts back on the Starliner or instead take them back seven months later in a SpaceX Dragon capsule.
“The decision of whether or not we will have a crew on board when the Starliner returns is a pretty big discussion.” Ken Bowersox, NASA’s deputy director of Space Operations Mission Directorate said at a press conference on Wednesday (August 14): “We expect the data analysis to be ready for a program board by mid to late next week and ready for a flight readiness review by the end of next week.”
Boeing built the Starliner capsule as part of NASA’s Commercial Crew Program, a partnership between the agency and private companies to transport astronauts into low Earth orbit after NASA’s space shuttles are retired in 2011.
Starliner launched on its first manned test flight from the Cape Canaveral Space Force Station in Florida on June 5. But not long after entering orbit, a series of faults occurred – 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.
Related: Fixing Boeing’s leaky Starliner – and returning stranded NASA astronauts to Earth – is a lot harder than it sounds
A hot-fire test conducted on July 27 while the spacecraft was docked to the ISS showed that thrust was normal, but NASA engineers are concerned that the previous engine problems could recur during the spacecraft’s approach to Earth. They also fear that the helium leaks could disable some of the spacecraft’s Orbital Maneuvering and Attitude Control (OMAC) system thrusters, which keep the spacecraft on its trajectory.
“The worst case scenario would be an integrated failure mechanism between the helium leaks and the RCS engines.” Steve Stichthe program manager of NASA’s Commercial Crew Program, said at an earlier press conference on August 7. “Then there could be cases that are not so easy to control – stress cases that the team is concerned about.”
NASA’s main contingency plan is to bring the astronauts home aboard a SpaceX Dragon capsule instead. The vehicle will be sent to the ISS as early as September 24 with members of ISS Crew-9, who will relieve 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.
“I want to keep this in mind: If Butch and Suni don’t come home on the Starliner, they will spend about 8 months in orbit,” Russ DeLoachNASA chief of safety and mission assurance, said at the press conference on August 14.
But despite the problems with the Starliner, NASA stated that its astronauts were safe and comfortable on board the ISS.
“This mission was a test flight… they knew this mission might not be perfect,” Joe AcabaNASA’s chief astronaut said at the press conference. “Human spaceflight is inherently risky, and as astronauts we accept that as part of our job.”
