Boeing is gearing up for another attempt to launch NASA astronauts aboard its Starliner spacecraft.
It’s a major test flight: the first time a crew will fly the vehicle to the International Space Station.
The launch was originally scheduled for May 6, but that attempt was canceled with about two hours remaining. Now, the launch is expected on Saturday at 12:25 PM ET from the Cape Canaveral Space Force Station, Florida. The spacecraft will enter orbit atop an Atlas V rocket built by United Launch Alliance, a joint venture of Boeing and Lockheed Martin.
The test flight must demonstrate that the Starliner can safely transport astronauts to and from the space station. If successful, NASA could allow Boeing to make routine trips to the orbiting outpost, which would give it a long-awaited second option to SpaceX’s Crew Dragon capsule.
Boeing’s May 6 launch was canceled due to a problem with a valve on the Atlas V rocket. NASA astronauts Barry “Butch” Wilmore and Sunita Williams were already trapped in the capsule when the mission controllers chose to stand down.
While work was underway to repair the booster’s faulty valve, another problem – this time a helium leak – was discovered in the Starliner capsule’s propulsion system, according to NASA. The discovery caused additional delays to a project that had suffered from years of setbacks and budget overruns.
At a news briefing last week, mission controllers 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 has been extensively analyzed and determined it is 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 separated 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 some systems failed while the helium leak persisted, the Starliner capsule could be left without enough functioning thrusters to perform crucial maneuvers, including burns from orbit . help the astronauts return to Earth.
Ultimately, however, mission managers said they felt comfortable moving forward with Saturday’s test flight.
“We could address this particular leak if the leak rate increased even up to a hundred times,” Stich said.
Representatives from NASA, Boeing and United Launch Alliance met Wednesday for a readiness review and officially voted to continue preparations for Saturday’s launch.
Wilmore and Williams, who 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 main 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 transporting NASA astronauts to and from the space station since 2020. Both companies developed their spacecraft as part of the Commercial Crew Program, which NASA established after the space shuttle fleet was retired. provide incentives and help pay for the creation of commercially built vehicles that can reach low Earth orbit.
However, the Starliner program has had many bumps along the way.
In 2019, the capsule’s unmanned debut flight was aborted after software issues prevented the capsule from docking with the space station. Subsequent fuel valve problems caused several delays before Boeing was able to demonstrate that the Starliner could dock with the ISS and return to Earth in 2022.
The company as a whole has also faced heightened criticism after a panel blew out one of its 737 Max 9 planes mid-flight.
This article was originally published on NBCNews.com
