"NASA, Boeing Space and ULA Launch [United Launch Alliance] are forgoing the May 25 launch attempt for the agency's Boeing Crew Flight Test following meetings assessing flight rationale, system performance, and redundancy," the US space agency said on X.
The next possible launch opportunity is still being discussed, NASA said. The message gave no indication when this might be.
US astronauts Barry "Butch" Wilmore and Sunita "Suni" Williams were scheduled to fly in the Starliner to the International Space Station (ISS) but after previous delays, a pressure regulation valve on the liquid oxygen tank on the Atlas V rocket’s Centaur upper stage had to be released.
The first manned Starliner flight was earlier scheduled for July 2023 but has been repeatedly postponed since then as parts failed to function properly during tests. Boeing has received more than $5 billion in contracts to build the much-troubled spacecraft which is now $1 billion over budget.
Starliner was supposed to complement the reliable and now repeatedly used and successful SpaceX Dragon spacecraft which has already flown 50 astronauts, cosmonauts and civilians into orbit in 13 flights, 12 of them to the ISS.