KENNEDY SPACE CENTER, Fla. — The first attempt to launch Boeing’s CST-100 Starliner on a crewed test flight on May 6 was canceled by controllers due to a valve problem with the rocket.
The launch director for the Atlas 5 rocket called off the scheduled 10:34 p.m. Eastern launch of the Crew Flight Test mission from Cape Canaveral Space Force Station in Florida a little more than two hours before it was set to take place.
The problem was with an oxygen relief valve on the rocket’s Centaur upper stage. “The team is just not comfortable with the signatures that they’re seeing, the response out of that valve, so out of an abundance of caution, we are not going to continue with our launch operations today,” said Dillon Rice, ULA launch commentator, on NASA TV.
ULA did not immediately provide additional details about the problem and how long it might take to correct. There are backup launch opportunities for the mission currently scheduled for May 7, 10 and 11.
The cancellation was announced shortly after NASA astronauts Butch Wilmore and Suni Williams had boarded Starliner. They had no reported no issues with the spacecraft leading up to the launch scrub.
CFT is the final test of the Starliner spacecraft before NASA certifies the spacecraft for International Space Station crew rotation missions. The flight will be the first to carry astronauts after two uncrewed flights in December 2019 and May 2022.
The spacecraft is scheduled to dock with the station a little more than a day after launch. It will remain at the station for about a week before undocking and landing at White Sands, New Mexico.
Before the flight, Wilmore and Williams said they were prepared to take a launch scrub in stride. When they arrived at the Kennedy Space Center April 25 for final preparations, Williams said she had gotten advice from Bob Behnken, who flew on the first Crew Dragon spacecraft to carry astronauts, Demo-2 in 2020, with Doug Hurley. That mission suffered a weather-related scrub before launching successfully.
“May 6 isn’t magical,” Williams said of the scheduled CFT launch. “He said, ‘If you get a scrub it is actually a little bit nice because it sort of takes the pressure off a little bit.’”
