Boeing Starliner valve fault fixed after 8-month hiatus in testing: headed to ISS on May 19

May 4 news, local time Wednesday, Boeing representatives and NASA officials said,Valve fault that interrupted Boeing’s CST-100 Starliner unmanned flight test for 8 months has been fixedthe spacecraft will lift off to the International Space Station on May 19.

The Starliner spacecraft will resume its Orbital Flight Test 2 (OFT-2) mission on May 19, NASA and Boeing said. It is reported that the spacecraft was originally scheduled to perform the OFT-2 mission to the International Space Station in August 2021. But standard pre-flight inspections prior to launch revealed,Thirteen of the 24 oxidation valves in the spacecraft’s service module propulsion system failed. Boeing and NASA engineers then worked together to troubleshoot the Starship and United Launch Alliance Atlas V rockets from the launch pad. A few months later, investigators found that the probable cause of the valve failure was the reaction of the nitrous tetroxide (NTO) oxidant with moisture in the air to produce nitric acid, which in turn corroded the valve’s aluminum casing, causing the valve to fail.

Boeing representatives and NASA officials said Wednesday that the initial diagnosis was accurate and that the problem has been successfully resolved.

“Very proud of the work of the Starship team and the NASA team over the past eight months,” said Steve Stich, NASA Commercial Crew Program Manager. “I’d say it’s been a tough eight months, but it’s very satisfying that we’ve fixed the oxidant isolation valve failure and the spacecraft is about to launch.”

Michelle Parker, vice president and deputy general manager of Boeing Aerospace and Launch, explained that technicians sealed “a channel that could leak moisture” in the valve’s electrical connector. The team is also now using nitrogen to keep moisture out of the valve, she said.

“In addition, we will load the NTO oxidizer later,” Parker said. “On an operational level, every two to five days after the oxidizer is loaded, we add valve cycles until the spacecraft is launched to ensure that the valve mechanism remains functional. “

Boeing also replaced the OFT-2 Starliner with a new service module and docked the assembly with the crew module on March 12.

If the OFT-2 mission goes as planned, the Starliner spacecraft will rendezvous with the International Space Station a day after launch, where it will stay for five to 10 days, NASA officials said.

The OFT-2 mission will be the second uncrewed test mission of the Starliner spacecraft to the International Space Station. The first test flight took place in December 2019, when the mission was interrupted when the Starliner spacecraft suffered a software glitch during its flight that prevented it from docking with the International Space Station.

Boeing has signed a contract with NASA to fly astronauts to and from the International Space Station on the Starliner spacecraft. The spacecraft will not begin carrying astronauts until it completes an uncrewed flight test, which Boeing hopes to complete by the end of this year.

In addition to Boeing, SpaceX, led by Elon Musk, has NASA commercial astronaut contracts. SpaceX has recently launched Crew-4, its fourth human spaceflight mission for NASA. The four astronauts flying the Crew-3 manned space mission are currently on the International Space Station and are scheduled to return to Earth in the early hours of Friday, local time in the United States.