Boeing Starliner's 1st astronaut launch delayed again, this time with no new flight date

a cone-shaped spacecraft inside a tall facility with an open door to the right, showing trees and swamp down below
Boeing's Crew Flight Test Starliner spacecraft is mated to its Atlas V rocket ahead of its first astronaut launch at Cape Canaveral Space Force Station in Florida. (Image credit: NASA)

The first astronaut mission aboard Boeing's Starliner is indefinitely grounded.

Starliner will not lift off on Saturday (May 25) as planned, which was the latest launch date following several delays in recent weeks. NASA officials communicated the delay late on Tuesday (May 21), providing no specific cause yet. But the team has been examining a small helium leak in a Starliner thruster in recent weeks.

"The team has been in meetings for two consecutive days, assessing flight rationale, system performance, and redundancy. There is still forward work in these areas, and the next possible launch opportunity is still being discussed," the e-mail update read in part.

Starliner's Crew Flight Test (CFT) mission to the International Space Station or ISS, as NASA and Boeing officials repeatedly have stressed, is developmental. In past briefings, officials say they always emphasize safety over schedules. NASA CFT astronauts Butch Wilmore and Suni Williams, both former U.S. Navy test pilots, have said much the same. 

Related: 2 astronaut taxis: Why NASA wants both Boeing's Starliner and SpaceX's Dragon

 Starliner appeared to be ready to fly on May 6, but the countdown was halted just two hours before liftoff, while Wilmore and Williams were being strapped into the spacecraft. (The helium leak was also ongoing during this time, but at that time engineers did not deem that an issue for launching.)

The delay was ultimately called after United Launch Alliance (ULA) found an oxygen relief valve issue on the Atlas V rocket set to launch the duo from the coastal Cape Canaveral Space Force Station near Orlando, Florida. The Atlas V has been flying missions since 2002 with 100% launch success, but CFT will be the first crewed launch for the rocket.

ULA determined the safer option would be to address the "buzzing" valve — it was opening and closing rapidly — without astronauts on board. After a few hours of evaluation, the team elected to pull the stacked rocket back to shelter to replace the valve.

NASA astronauts Butch Wilmore (left) and Suni Williams (background, to the right of Wilmore) during the crew walkout ahead of a launch attempt for Boeing's Starliner on May 6, 2024. The launch was later delayed due to an issue with the United Launch Alliance Atlas V rocket. Williams and Wilmore, both former U.S. Navy test pilots, are the astronauts on Crew Flight Test scheduled to fly Starliner's first mission with astronauts. (Image credit: Ron Brecher)

While in the ULA facility, the team scrutinized the helium leak and announced delays, first to May 21, and then to May 25. "The additional time allows teams to further assess a small helium leak in the Boeing Starliner spacecraft's service module traced to a flange on a single reaction control system thruster," NASA officials wrote in a previous update.

Helium is a non-combustible gas and does not pose a risk during ground operations, but proper pressure is needed to send propellant to Starliner's dozens of engines. This helium leak was found in a part of the spacecraft used for small maneuvers in orbit, according to multiple media reports.

Starliner is only authorized to dock to one port of the Harmony module of the ISS on this test mission, meaning NASA needs to preserve that spot open for CFT to launch. If the fix takes several weeks, it may be difficult for NASA to hold the spot open given the ISS hosts other cargo and astronaut missions. That is likely one factor behind the uncertainty of the launch date.

Williams and Wilmore had remained in quarantine through the launch delays, flying back to NASA's Johnson Space Center in Houston in mid-May. NASA did not say if the astronauts will emerge from their quarters, but if the delay persists for many weeks it is likely they will leave to focus on other CFT training duties.

Developmental delays often arise in new space programs. Boeing and SpaceX were both tasked by NASA in 2014 to send astronauts to the ISS using commercial crew vehicles. The target date for astronaut flights at that time was 2017. 

SpaceX, borrowing from its cargo Dragon design that began flights in 2012, flew its first Crew Dragon with astronauts successfully in 2020. Starliner's waited much longer.

Starliner failed to reach the ISS during its first uncrewed test flight in 2019 due to a software glitch that stranded the spacecraft in the wrong orbit. A follow-up flight made it there safely in 2022 after addressing the dozens of issues, in addition to experiencing other delays in part due to the outbreak of the coronavirus pandemic in March 2020.

CFT was delayed further in 2023 after the team found the capsule's parachutes could carry less load than expected, and discovered flammable tape covering much of the wiring in the spacecraft. Those issues are behind the team, however, NASA and Boeing officials said in the spring.

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Elizabeth Howell
Staff Writer, Spaceflight

Elizabeth Howell (she/her), Ph.D., is a staff writer in the spaceflight channel since 2022 covering diversity, education and gaming as well. She was contributing writer for for 10 years before joining full-time. Elizabeth's reporting includes multiple exclusives with the White House and Office of the Vice-President of the United States, an exclusive conversation with aspiring space tourist (and NSYNC bassist) Lance Bass, speaking several times with the International Space Station, witnessing five human spaceflight launches on two continents, flying parabolic, working inside a spacesuit, and participating in a simulated Mars mission. Her latest book, "Why Am I Taller?", is co-written with astronaut Dave Williams. Elizabeth holds a Ph.D. and M.Sc. in Space Studies from the University of North Dakota, a Bachelor of Journalism from Canada's Carleton University and a Bachelor of History from Canada's Athabasca University. Elizabeth is also a post-secondary instructor in communications and science at several institutions since 2015; her experience includes developing and teaching an astronomy course at Canada's Algonquin College (with Indigenous content as well) to more than 1,000 students since 2020. Elizabeth first got interested in space after watching the movie Apollo 13 in 1996, and still wants to be an astronaut someday. Mastodon:

  • JoeWingNut
    Ground it permanently. Drag it over to the static display park. Let's stop wasting money on this lemon!
    Start over on Boeing's dime.
  • Ryan F. Mercer
    JoeWingNut said:

    Or just throw money at Starship. Who needs Boeing?
  • fj.torres
    At the current rate, Dream Chaser will be human rated before Starliner.
  • Mergatroid
    Just scrap the damn thing and go back to the drawing board.
    The thing is obviously not reliable, and considering who made it, I would never want to trust my life to it.
    In my eyes, Boeing has lost most of the credibility it had built up over previous decades before all these problems started becoming apparent.
    Didn't SpaceX and Boeing start the design and build at approximately the same time? Yet the Dragon capsule has successfully has how many human flights?
    From Wikki:
    "On September 16, 2014, NASA chose Boeing (Starliner) and SpaceX (Crew Dragon) as the two companies to be funded to develop systems to transport U.S. government crews to and from the International Space Station."

    Maybe they should have had something that works by now?
  • HumboldtRick
    Why do these rich idiots make their rockets look like penises??? Shows where their heads are at.
  • Classical Motion
    I was thinking of spearhead, a stick with a blade. See, it's either sex or killing.
  • Rob77
    I would start investigation whether Starliner was actually launch ready or just a publicity stunt to give them selves more time to fix issues. If they gave the appearance that they are "launch ready" it might get key investors / government off their back for a while .... hmmm
  • Eskalab
    Maybe they need to go to a hobby store and buy some Estes rockets 🚀
  • ultimatewizz
    Considering that the people launching it if they ever do, do not recover the booster and cannot come close to SpaceX in cost. So why is NASA throwing money down the toilet, they can't get their samples back from Mars, not sure they can repair Hubble. Put the money to use somewhere else.
  • Dale H
    JoeWingNut said:
    Ground it permanently. Drag it over to the static display park. Let's stop wasting money on this lemon!
    Start over on Boeing's dime.
    I agree. Boeing had a contract for $4.2 billion vs $2.6 billion for SpaceX. SpaceX has been flying to the ISS for several years now and Boeing seems to have no idea what they are doing. Time to end it and apply the remaining funds to SpaceX.