NASA’s Boeing crew flight tests will not begin until Friday the 17th.

05/11/2024

After a thorough data review completed last Tuesday, ULA (United Launch Alliance) has decided to replace the pressure control valve in the Atlas V rocket’s Centaur upper stage liquid oxygen tank, which was to blame for the launch cancellation.

The rocket, already at the Vertical Integration Center at the Cape Canaveral Space Station, is undergoing a series of integrity and functional checks in support of its upcoming launch attempt on the 17th.

Oscillatory behavior of the valve during pre-launch operations forced the mission teams to cancel the May 6 launch. After ground crews and astronauts Butch Wilmore and Suni Williams left Space Launch Complex 41, the ULA team was able to close the valve and temporarily dampen the vibrations.

The oscillations were repeated twice during fuel withdrawal operations. After evaluating the valve’s history, the launch attempt’s data signatures, and assessing the risks associated with its continued use, the ULA team determined that the valve was not compliant, and mission managers agreed to remove and replace it.

Mission leaders discussed details of the decision to cancel the May 6 launch during a news conference held shortly after the cancellation was announced at NASA’s Kennedy Space Center in Florida.

Wilmore and Williams will remain in the crew quarters on NASA’s Kennedy Space Station in quarantine until the next launch opportunity. The duo will be the first to fly aboard Starliner to the space station as part of the agency’s commercial crew program.