The first launch of Boeing’s Starliner spacecraft with astronautshas been pushed back yet again.
The Starliner’s maiden crewed flight with NASA astronauts Butch Wilmore and Suni Williams was supposed to launch from the Kennedy Space Center in Florida on May 6, but two hours before launch, engineers spotted an issue with a pressure regulation valve on the Atlas V rocket’s upper stage, prompting the mission team to halt the countdown clock.
A revised schedule for the trip to the International Space Station (ISS) had targeted May 17 for launch, but on Tuesday NASA announced that it is now targeting May 21 as it needs to complete additional testing.
NASA explained that after engineers successfully replaced the valve on Saturday, a “small helium leak” had been detected on the Starliner’s service module, the source of which it has managed to trace.
“NASA and Boeing are developing spacecraft testing and operational solutions to address the issue,” the space agency said in a release on Tuesday. “As a part of the testing, Boeing will bring the propulsion system up to flight pressurization just as it does prior to launch, and then allow the helium system to vent naturally to validate existing data and strengthen flight rationale.”
The Atlas V and Starliner are currently sheltered at the Vertical Integration Facility at Space Launch Complex-41 at Cape Canaveral Space Force Station in Florida. Wilmore and Williams, meanwhile, remain in preflight quarantine and traveled back to Houston on May 10 to spend time with their families while engineers prepare the rocket and spacecraft for next week’s launch
During the highly anticipated mission, the two astronauts will spend about a week aboard the space station before returning to Earth in a parachute- and airbag-assisted landing in the southwestern U.S. After that, NASA will begin the final process of certifying Starliner and its systems for crewed rotation missions to the space station, alongside SpaceX’s Crew Dragon spacecraft.
The Starliner’s development has faced numerous delays over the years. Its first attempt to reach the space station in its first uncrewed test flight in 2019 ended in failure when the vehicle was unable to enter the correct orbit. The mission surfaced a slew of issues with the capsule’s software systems that had to be addressed before it could fly again. A second uncrewed test flight in 2022 managed to dock with the space station, but a number of new issues had to be resolved to get the Starliner ready for the first crewed flight, which will hopefully launch next week.