Boeing is preparing for another attempt to launch NASA astronauts aboard its Starliner spacecraft.
It’s a key test flight — the first time a crew will fly a vehicle to the International Space Station.
The launch was originally scheduled for May 6, but the attempt was called off with about two hours left in the countdown. It is now expected to launch at 12:25pm ET on Saturday from the Cape Canaveral Space Force Station in Florida. The spacecraft will fly into orbit atop an Atlas V rocket built by United Launch Alliance, a joint venture between Boeing and Lockheed Martin.
The test flight is intended to demonstrate that the Starliner can safely transport astronauts to and from the space station. If successful, NASA may allow Boeing to make routine trips to the orbital base, giving it a long-awaited second option to SpaceX’s Crew Dragon pod.
Boeing’s May 6 launch was canceled due to a valve problem on the Atlas V rocket. NASA astronauts Barry “Butch” Wilmore and Sunita Williams were already seated and strapped into the capsule when mission control decided to stand up.
While work was underway to repair the malfunctioning booster valve, a separate problem was found in the Starliner capsule’s propulsion system, according to NASA — this time a helium leak. The discovery forced further delays to the project, which had already faced years of setbacks and budget overruns.
At a press conference last week, mission managers said the rocket’s valve had been successfully replaced, but added that the helium leak would not be repaired before the upcoming flight.
Steve Stich, manager of NASA’s Commercial Crew Program, said the slow leak was analyzed extensively and was found to be unlikely to pose a threat to the crew, mission or spacecraft.
Repairing the leak would require a much longer delay because the spacecraft would have to be disconnected from the rocket, said Mark Nappi, Boeing’s vice president for the commercial crew program.
Stich called the problem a “design vulnerability” because, in the unlikely event that a number of systems failed while the helium leak persisted, it could leave the Starliner’s pod without enough functional thrusters to perform essential maneuvers, including de-orbital burnouts. to help the astronauts return to Earth.
Ultimately, however, mission managers said they felt comfortable continuing with Saturday’s test flight.
“We could handle this particular leak if the leak rate increased even up to 100 times,” Stich said.
Representatives from NASA, Boeing and the United Launch Alliance met Wednesday to assess readiness and officially voted to continue preparations for Saturday’s launch.
Wilmore and Williams, who had been quarantined in Houston while engineers worked on the rocket and spacecraft, arrived back at NASA’s Kennedy Space Center in Florida on Tuesday.
If all goes according to plan, they will spend about a week on the International Space Station before returning to Earth and landing at the Starliner’s primary landing site at the White Sands Missile Range in New Mexico.
Boeing hopes to challenge the dominance of Elon Musk’s SpaceX, which has been ferrying NASA astronauts to and from the space station since 2020. Both companies developed their spacecraft under the Commercial Crew Program, which NASA established after its space shuttle fleet was retired. to provide incentives and help pay for the creation of commercially produced vehicles capable of reaching low Earth orbit.
However, the Starliner program experienced many bumps along the way.
In 2019, the capsule’s first unmanned flight was aborted after software glitches prevented an attempt to dock with the space station. Subsequent problems with the fuel valves caused several delays before Boeing could demonstrate in 2022 that the Starliner could dock with the ISS and return to Earth.
The company as a whole has also faced increased scrutiny after a panel on one of its 737 Max 9 jets exploded mid-flight.