ULA ’s Atlas V rocket and Boeing Space ’s Starliner spacecraft on the launchpad at the Kennedy Space Center in Florida . NASA/ Joel Kowsky

NASA has announce a novel target date for the first crew flight of Boeing Space ’s Starliner spaceraft .

The space way said Wednesday that it ’s now direct no to begin with no earlier than 6:16 p.m. ET on May 17 for the launch of the Atlas V Eruca vesicaria sativa and Starliner spacecraft from the Kennedy Space Center in Florida .

ULA’s Atlas V rocket and Boeing Space’s Starliner spacecraft on the launchpad at the Kennedy Space Center in Florida.

ULA’s Atlas V rocket and Boeing Space’s Starliner spacecraft on the launchpad at the Kennedy Space Center in Florida.NASA/ Joel Kowsky

The Starliner was supposed to establish Monday , May 9 , but an issue with a valve on the upper stage of United Launch Alliance ’s rocket emergedjust two hour before liftoff , prompting the escape to be scrubbed . NASA astronauts Butch Wilmore and Suni Williams had just been strapped into their seats inside the spacecraft when news came through that the delegacy had been called off for the day .

Teams from ULA have now rolled the Starliner and Atlas V arugula to an consolidation installation to replace the faulty valve on the rocket ’s upper stage . Wilmore and Williams have return to quarantine inside NASA facilities , where they ’ll remain until next week ’s launch attempt .

“ The oscillating behavior of the valve during prelaunch operations ultimately result in mission team call a launching scrub on May 6 , ” NASA suppose in the financial statement . “ After the primer crews and spaceman Butch Wilmore and Suni Williams safely decease from Space Launch Complex-41 , the ULA squad successfully commanded the valve close and the oscillation were temporarily dampened . The oscillations then re - occurred twice during fuel remotion operations . After appraise the valve story , datum signature from the launching attempt , and assessing the hazard proportional to continued use of goods and services , the ULA team ascertain the valve exceeded its qualification and mission managers agreed to remove and replace the valve . ”

It ’s a setback for the mission team but base hit has to number first , and so engineers decided out of an abundance of precaution to halt the countdown clock and prepare launch for another Clarence Shepard Day Jr. .

When the commission finally gets afoot , Wilmore and Williams will pilot to the International Space Station ( ISS ) and stay for about a calendar week before come back home . The bearing of the flight is to confirm the operability of the Starliner ’s onboard systems so that the vehicle can be used by NASA to carry crews to and from low - Earth orbit in the same style that SpaceX ’s Crew Dragon capsule has been doing since 2020 .

The Starliner projection has been delayed many times over the years as Boeing worked on a plethora of proceeds that emerged keep abreast the spacecraft ’s first trial flight in 2019 when it go bad to reach the ISS . Another uncrewed test trajectory in 2022saw the Starliner tail with the ISSbefore returning to Earth in a successful parachute landing .