NASA Decides to Bring Starliner Spacecraft Back to Earth Without Crew

Boeing’s Starliner crew capsule docked to the Harmony module’s forward port at the International Space Station on July 3, 2024.
Photo credit: NASA

NASA will return Boeing’s Starliner to Earth without astronauts Butch Wilmore and Suni Williams aboard the spacecraft, the agency announced Saturday during a news conference. The uncrewed return allows NASA and Boeing to continue gathering testing data on Starliner during its upcoming flight home, while also not accepting more risk than necessary for its crew. The news conference is available here.

Wilmore and Williams, who flew to the International Space Station in June aboard NASA’s Boeing Crew Flight Test, have been busy supporting station research, maintenance, and Starliner system testing and data analysis, among other activities.

“Spaceflight is risky, even at its safest and most routine. A test flight, by nature, is neither safe, nor routine. The decision to keep Butch and Suni aboard the International Space Station and bring Boeing’s Starliner home uncrewed is the result of our commitment to safety: our core value and our North Star,” said NASA Administrator Bill Nelson. “I’m grateful to both the NASA and Boeing teams for all their incredible and detailed work.”

Wilmore and Williams will continue their work formally as part of the Expedition 71/72 crew through February 2025. They will fly home aboard a Dragon spacecraft with two other crew members assigned to the agency’s SpaceX Crew-9 mission. Starliner is expected to depart from the space station and make a safe, controlled autonomous re-entry and landing in early September.

NASA and Boeing identified helium leaks and experienced issues with the spacecraft reaction control thrusters on June 6 as Starliner approached the space station. Since then, engineering teams have completed a significant amount of work, including reviewing a collection of data, conducting flight and ground testing, hosting independent reviews with agency propulsion experts, and developing various return contingency plans. The uncertainty and lack of expert concurrence does not meet the agency’s safety and performance requirements for human spaceflight, thus prompting NASA leadership to move the astronauts to the Crew-9 mission.

“Decisions like this are never easy, but I want to commend our NASA and Boeing teams for their thorough analysis, transparent discussions, and focus on safety during the Crew Flight Test,” said Ken Bowersox, associate administrator for NASA’s Space Operations Mission Directorate. “We’ve learned a lot about the spacecraft during its journey to the station and its docked operations. We also will continue to gather more data about Starliner during the uncrewed return and improve the system for future flights to the space station.”

Starliner is designed to operate autonomously and previously completed two uncrewed flights. NASA and Boeing will work together to adjust end-of-mission planning and Starliner’s systems to set up for the uncrewed return in the coming weeks. Starliner must return to Earth before the Crew-9 mission launches to ensure a docking port is available on station.

“Starliner is a very capable spacecraft and, ultimately, this comes down to needing a higher level of certainty to perform a crewed return,” said Steve Stich, manager of NASA’s Commercial Crew Program. “The NASA and Boeing teams have completed a tremendous amount of testing and analysis, and this flight test is providing critical information on Starliner’s performance in space. Our efforts will help prepare for the uncrewed return and will greatly benefit future corrective actions for the spacecraft.”

NASA’s Commercial Crew Program requires spacecraft fly a crewed test flight to prove the system is ready for regular flights to and from the space station. Following Starliner’s return, the agency will review all mission-related data to inform what additional actions are required to meet NASA’s certification requirements.

The agency’s SpaceX Crew-9 mission, originally slated with four crew members, will launch no earlier than Tuesday, Sept. 24. The agency will share more information about the Crew-9 complement when details are finalized.

NASA and SpaceX currently are working several items before launch, including reconfiguring seats on the Crew-9 Dragon, and adjusting the manifest to carry additional cargo, personal effects, and Dragon-specific spacesuits for Wilmore and Williams. In addition, NASA and SpaceX now will use new facilities at Space Launch Complex-40 at Cape Canaveral Space Force Station in Florida to launch Crew-9, which provides increased operational flexibility around NASA’s planned Europa Clipper launch.

The Crew-9 mission will be the ninth rotational mission to the space station under NASA’s Commercial Crew Program, which works with the American aerospace industry to meet the goal of safe, reliable, and cost-effective transportation to and from the orbital outpost on American-made rockets and spacecraft launching from American soil.

For more than two decades, people have lived and worked continuously aboard the International Space Station, advancing scientific knowledge and demonstrating new technologies, making research breakthroughs not possible on Earth. The station is a critical testbed for NASA to understand and overcome the challenges of long-duration spaceflight and to expand commercial opportunities in low Earth orbit. As commercial companies focus on providing human space transportation services and destinations as part of a robust low Earth orbit economy, NASA’s Artemis campaign is underway at the Moon where the agency is preparing for future human exploration of Mars.

NASA, Boeing Discuss Ground Testing, Forward Work for Starliner Return

Boeing's Starliner spacecraft as it approaches the International Space Station. Also in view is the Earth below it.
Boeing’s Starliner spacecraft, with NASA astronauts Butch Wilmore and Suni Williams aboard, approaches the International Space Station for an autonomous docking as it orbited 257 miles above the South Pacific Ocean on June 6, 2024. Photo credit: NASA Television

NASA and Boeing leadership provided an update on Starliner’s Crew Flight Test during a news conference Thursday. The integrated Starliner team continues to assess the spacecraft’s propulsion system performance and complete other tasks before scheduling its undocking from the International Space Station and return to Earth. Watch the full replay of the news conference.

Engineering teams from NASA and Boeing recently wrapped up ground hot fire testing of a Starliner reaction control system thruster at the agency’s White Sands Test Facility in New Mexico. The test series involved firing the engine under conditions like those the spacecraft experienced during its approach to the space station. The tests also included various stress-case scenarios to simulate the conditions expected during Starliner’s undocking and deorbit burn, which will position the spacecraft for landing in the southwestern United States. Teams are in the process of taking apart this thruster to conduct physical inspections. Initial findings show degraded thruster performance, which aligns with what has been observed in orbit.

Additionally, NASA and Boeing will conduct a second docked hot fire test over the weekend to demonstrate the spacecraft’s thruster performance. The first docked hot fire test occurred on June 15. The upcoming test will allow checks of the helium leaks while also verifying the thrusters are operating as expected.

NASA plans to hold an agency-level readiness review no earlier than next week. Following the review, mission leadership will finalize the plan for a normal return to Earth and select a targeted undocking date for Starliner. NASA also plans to host a televised briefing with agency and Boeing leadership following the review. More news conference details will be shared when available.

NASA astronauts Butch Wilmore and Suni Williams continue to provide additional crew time and valuable contributions aboard the space station, assisting with science investigations and helping ground teams collect critical data for post-certification, long-duration Starliner flights to the orbiting complex.

Follow the commercial crew blog, @commercial_crew on X, and commercial crew on Facebook for the latest mission updates.

UPDATE: NASA, Boeing to Stream Flight Test Mission Briefing on NASA+

Image shows Boeing's Starliner spacecraft that launched NASA's Crew Flight Test astronauts Butch Wilmore and Suni Williams to the International Space Station is pictured docked to the Harmony module's forward port. This long-duration photograph was taken at night from the orbital complex as it soared 258 miles above western China.
Boeing’s Starliner spacecraft that launched NASA’s Crew Flight Test astronauts Butch Wilmore and Suni Williams to the International Space Station is pictured docked to the Harmony module’s forward port. This long-duration photograph was taken at night from the orbital complex as it soared 258 miles above western China. Photo credit: NASA

NASA and Boeing will host a news conference with mission leadership at 11:30 a.m. EDT Thursday, July 25, to provide the latest status of the agency’s Boeing Crew Flight Test aboard the International Space Station. NASA previously planned an audio-only media teleconference to host the discussion.

The agency will provide live coverage on NASA+, NASA Television, the NASA appYouTube, and the agency’s website. Learn how to stream NASA content through a variety of platforms, including social media.

Participants include:

  • Steve Stich, manager, NASA’s Commercial Crew Program
  • Mark Nappi, vice president and program manager, Commercial Crew Program, Boeing

United States-based media seeking to attend in person must contact the newsroom at NASA’s Johnson Space Center in Houston no later than 9:30 a.m. EDT Thursday, July 25, at 281-483-5111 or jsccommu@mail.nasa.gov. U.S. and international media interested in participating by phone must contact NASA Johnson or NASA’s Kennedy Space Center in Florida at ksc-newsroom@mail.nasa.gov by 10:30 a.m. the day of the event. A copy of NASA’s media accreditation policy is online.

Read the full advisory here.

NASA, Boeing to Discuss Crew Flight Test Mission, Ground Testing

Looking down at Boeing's Starliner spacecraft attached to the International Space Station.
The Starliner spacecraft on NASA’s Boeing Crew Flight Test is pictured docked to the Harmony module’s forward port as the International Space Station orbited 263 miles above the Mediterranean Sea. Photo credit: NASA

Leadership from NASA and Boeing will participate in a media teleconference at 11:30 a.m. EDT Thursday, July 25, to provide the latest status of the agency’s Boeing Crew Flight Test mission aboard the International Space Station.

Audio of the media teleconference will stream live on the agency’s website. Participants include:

  • Steve Stich, manager, NASA’s Commercial Crew Program
  • Mark Nappi, vice president and program manager, Commercial Crew Program, Boeing

Engineering teams with NASA and Boeing recently completed ground hot fire testing of a Starliner reaction control system thruster at White Sands Test Facility in New Mexico. The test series involved firing the engine through similar in-flight conditions the spacecraft experienced during its approach to the space station, as well as various stress-case firings for what is expected during Starliner’s undocking and the deorbit burn that will position the spacecraft for a landing in the southwestern United States. Teams are analyzing the data from these tests, and leadership plans to discuss initial findings during the call.

Read the full advisory here.

NASA, Boeing Complete Starliner Engine Testing, Continue Analysis

Boeing's Starliner spacecraft that launched NASA's Crew Flight Test astronauts Butch Wilmore and Suni Williams to the International Space Station is pictured docked to the Harmony module's forward port. This long-duration photograph was taken at night from the orbital complex as it soared 256 miles above the Arabian Sea off the coast of Mumbai, India.
Boeing’s Starliner spacecraft that launched NASA’s Crew Flight Test astronauts Butch Wilmore and Suni Williams to the International Space Station is pictured docked to the Harmony module’s forward port. This long-duration photograph was taken at night from the orbital complex as it soared 256 miles above the Arabian Sea off the coast of Mumbai, India. Photo credit: NASA

NASA and Boeing engineers are evaluating results from last week’s engine tests at NASA’s White Sands Test Facility in New Mexico as the team works through plans to return the agency’s Boeing Crew Flight Test from the International Space Station in the coming weeks.

Teams completed ground hot fire testing at White Sands and are working to evaluate the test data and inspect the test engine. The ongoing ground analysis is expected to continue throughout the week. Working with a reaction control system thruster built for a future Starliner spacecraft, ground teams fired the engine through similar inflight conditions the spacecraft experienced on the way to the space station. The ground tests also included stress-case firings, and replicated conditions Starliner’s thrusters will experience from undocking to deorbit burn, where the thrusters will fire to slow Starliner’s speed to bring it out of orbit for landing in the southwestern United States. For a detailed overview of the test plans, listen to a replay of a recent media teleconference with NASA and Boeing leadership.

“I am extremely proud of the NASA, Boeing team for their hard work in executing a very complex test series,” said Steve Stich, manager, NASA’s Commercial Crew Program. “We collected an incredible amount of data on the thruster that could help us better understand what is going on in flight. Next, our team has moved into engine tear downs and inspections which will provide additional insight as we analyze the results and evaluate next steps.”

Integrated ground teams also are preparing for an in-depth Agency Flight Test Readiness Review, which will evaluate data related to the spacecraft’s propulsion system performance before its return to Earth. The date of the agency review has not yet been solidified.

NASA and Boeing leadership plan to discuss the testing and analysis work in detail during a media briefing next week. More information on the briefing will be made available soon.

While testing and analysis are happening on Earth, NASA astronauts Butch Wilmore, Starliner mission commander, and Suni Williams, mission pilot, are working alongside the Expedition 71 crew. The two participated in vein scans using the Ultrasound 2 device on Monday. Doctors on the ground monitored in real-time as the pair took turns imaging each other’s neck, shoulder, and leg veins. Afterward, Wilmore scanned the veins of fellow NASA astronaut Matthew Dominick, helping researchers understand how microgravity affects the human body.

Wilmore and Dominick also spent a portion of the day taking inventory of the food stored aboard the space station. Williams worked on a pair of studies, first exploring the use of microgravity to manufacture higher-quality optical fibers than on Earth. Williams also investigated using fluid physics, such as surface tension, to overcome the lack of gravity when watering and nourishing plants grown in space.

Follow the commercial crew blog, @commercial_crew on X, and commercial crew on Facebook for the latest mission updates.

Crew Flight Test Astronauts Contribute to Station Science, Research

NASA's Boeing Crew Flight Test astronauts Suni Williams and Butch Wilmore prepare orbital plumbing hardware for installation inside the International Space Station’s bathroom
NASA’s Boeing Crew Flight Test astronauts Suni Williams and Butch Wilmore prepare orbital plumbing hardware for installation inside the International Space Station’s bathroom, also known as the waste and hygiene compartment, located in the Tranquility module. Photo credit: NASA

NASA astronauts Butch Wilmore, commander, and Suni Williams, pilot, of NASA’s Boeing Crew Flight Test, continue contributing to International Space Station research and activities since their arrival on June 6 to the orbiting laboratory. Wilmore and Williams have completed half of all hands-on research time conducted aboard the station as the expedition crew prepares for the departure of Northrop Grumman’s Cygnus. As packing takes most of the crew’s time, the extra help from Wilmore and Williams allows packing and research to happen simultaneously. To learn more about what other crew members are doing aboard the International Space Station, visit: blogs.nasa.gov/spacestation.

Media are invited to hear Wilmore and Williams discuss their mission during an Earth-to-space call at 11 a.m. EDT Wednesday, July 10. Read the agency’s coverage advisory for more information.

On July 1, Wilmore and Williams spent the morning in the Permanent Multipurpose Module, organizing stowage and tidying up. Wilmore then moved into the Japanese Experiment Module to disassemble an empty NanoRacks CubeSat Deployer in preparation for upcoming NanoRacks missions.

Later, Wilmore prepped and viewed samples for the Moon Microscope, a demonstration that allows flight surgeons on Earth to diagnose illnesses and could provide diagnostic capabilities for crews on future missions to the Moon and Mars. Meanwhile, Williams conducted some routine orbital pluming, then audited U.S. stowage items housed inside the Zarya module.

On July 2, Wilmore joined NASA astronaut Tracy Dyson to load trash and discarded gear inside Northrop Grumman’s Cygnus spacecraft. Cygnus is scheduled to be released from the Unity module later this month for disposal over the South Pacific Ocean, ending its five-and-a-half-month stay at the orbiting lab.

Williams spent most of Tuesday on Starliner operations and then assessed the air flow of the pump filter attached to the Advanced Plant Habitat. At the end of the day, Williams and all eight of her crewmates held a conference with ground teams.

Also, on July 2, teams brought the Starliner spacecraft out of quiescent mode to conduct mission data loads, or MDLs. These are files for the spacecraft’s computer to understand current inertial and relative navigation states, Earth rotation, thermal conditioning, and more. The spacecraft was commanded back to a docked quiescent mode after MDL loading was complete.

For more information on NASA’s Commercial Crew Program, visit:

https://www.nasa.gov/commercialcrew

NASA, Boeing Discuss Ground Testing, Starliner Timeline

The Starliner spacecraft on NASA's Boeing Crew Flight Test is pictured docked to the Harmony module's forward port as the International Space Station orbited 262 miles above Egypt's Mediterranean coast.
The Starliner spacecraft on NASA’s Boeing Crew Flight Test is pictured docked to the Harmony module’s forward port as the International Space Station orbited 262 miles above Egypt’s Mediterranean coast. Photo credit: NASA

During a media teleconference Friday, leaders from NASA and Boeing provided an update about Starliner’s Crew Flight Test. The integrated Starliner team continues to evaluate the spacecraft’s propulsion system performance and complete other forward work before scheduling undocking from the International Space Station. Listen to a full replay of the teleconference.

“Our goal is to bring Butch and Suni home aboard Boeing’s spacecraft, and we are working to confirm Starliner will perform as designed to return them safely to Earth,” said Ken Bowersox, associate administrator, NASA’s Space Operations Mission Directorate, NASA Headquarters in Washington. “Space station gives us the luxury of time, allowing us to look at data we gathered on the way uphill and conduct some additional testing. We’re still in the middle of a test mission, and we want to spend more time with the data before we make the final call to put the crew aboard the spacecraft for return.”

NASA and Boeing will conduct additional ground testing at White Sands Test Facility in New Mexico to better understand the spacecraft’s thruster performance. This testing will expose Starliner’s thrusters to flight-like pulse counts and thermal conditions for ground teams to inspect and analyze. The data collected also will help determine system improvements for future post-certification missions to station.

“We spent a lot of time working to determine whether we could get meaningful data from a ground hot fire to better inform our decision making in flight, and I am extremely proud of our integrated NASA and Boeing teams for coming up with some innovative options and leveraging testing plans that were already in place for future missions,” said Steve Stich, manager of NASA’s Commercial Crew Program. “Based on the continued performance of Starliner while docked, we are working with station to extend the certification of several components beyond a 45-day mission duration, if needed, so our engineering teams can take the time they need while Butch and Suni support various in-orbit activities that are critical for sustaining station operations and research.”

Engineering teams are working to finalize testing plans and a timeline for the additional ground testing, which should occur over the next two weeks. They are taking advantage of the extra time by gathering as much data as possible while docked to station, considering the service module will not be recovered at the end of the mission.

Since Starliner’s arrival on June 6 with NASA astronauts Butch Wilmore and Suni Williams aboard, mission teams have been working to complete open work related to managing five small leaks in the spacecraft’s service module helium manifolds while reaffirming the health of the spacecraft’s reaction control system thrusters. Starliner remains available in case of an emergency on the space station that would require the crew to leave orbit immediately and return to Earth.

In addition to monitoring the hardware in orbit, which is operating normally in a docked state, NASA and Boeing continue testing and analysis on the ground by exploring potential causes for the helium system leaks and analyzing instrumentation data on Starliner’s thrusters. Engineers are working to gauge potential helium leak rates that may occur after undocking, validate operational mitigations for use in flight as needed, and explore fault tree considerations beyond what the teams have already gathered from the flight data.

They also are evaluating recent ground test results that showed better than expected performance of Starliner’s thruster instrumentation. Based upon these results, engineering teams have confidence that Starliner’s thruster pressure transducers are not overheating in flight and causing premature deselects of the thrusters in orbit, which was initially considered to be a possibility. Meanwhile, simulated propulsion system contingency scenarios continue to be worked in the lab to ensure expected performance of Starliner’s backup systems and thruster combinations for use during the return if needed.

Once all the necessary ground testing and associated data analysis is complete, leaders from NASA’s Commercial Crew and International Space Station Programs and Boeing will conduct an agency-level review. During the review, senior agency leaders and mission managers will discuss their findings and options with the broader NASA community, including international partners, to formally document the agency’s acceptance of Starliner’s flight plan and evaluate future return opportunities.

NASA plans to host a televised media briefing following the agency review to discuss the next steps ahead of Starliner’s return. The agency will share details on that briefing once it is finalized.

Wilmore and Williams continue to provide additional crew time and valuable contributions aboard the space station, assisting with spacewalks and science investigations while helping ground teams collect critical data for post-certification, long-duration Starliner flights to the orbiting complex.

Follow the commercial crew blog, @commercial_crew on X, and commercial crew on Facebook for the latest mission updates.

NASA, Boeing Adjust Timeline for Starliner Return

An aurora streams below Boeing's Starliner spacecraft docked to the forward port on the Harmony module as the International Space Station soared 266 miles above the Indian Ocean southwest of Australia.
An aurora streams below Boeing’s Starliner spacecraft docked to the forward port on the Harmony module as the International Space Station soared 266 miles above the Indian Ocean southwest of Australia. Photo credit: NASA/Matt Dominick

NASA and Boeing leadership are adjusting the return to Earth of the Starliner Crew Flight Test spacecraft with agency astronauts Butch Wilmore and Suni Williams from the International Space Station. The move off Wednesday, June 26, deconflicts Starliner’s undocking and landing from a series of planned International Space Station spacewalks while allowing mission teams time to review propulsion system data. Listen to a full replay of the June 18 media briefing where NASA and Boeing leadership discussed the ongoing efforts.

“We are taking our time and following our standard mission management team process,” said Steve Stich, manager of NASA’s Commercial Crew Program. “We are letting the data drive our decision making relative to managing the small helium system leaks and thruster performance we observed during rendezvous and docking. Additionally, given the duration of the mission, it is appropriate for us to complete an agency-level review, similar to what was done ahead of the NASA’s SpaceX Demo-2 return after two months on orbit, to document the agency’s formal acceptance on proceeding as planned.”

A media telecon with mission leadership will follow the readiness review’s conclusion, and the agency will share those details as they are solidified. Boeing’s Starliner spacecraft remains cleared for return in case of an emergency on the space station that required the crew to leave orbit and come back to Earth.

Mission managers are evaluating future return opportunities following the station’s two planned spacewalks on Monday, June 24, and Tuesday, July 2.

“Starliner is performing well in orbit while docked to the space station,” said Stich. “We are strategically using the extra time to clear a path for some critical station activities while completing readiness for Butch and Suni’s return on Starliner and gaining valuable insight into the system upgrades we will want to make for post-certification missions.”

Wilmore and Williams remain integrated with the Expedition 71 crew, assisting with station operations as needed and completing add-on in-flight objectives for NASA certification of Starliner.

“The crew’s feedback has been overwhelmingly positive, and they know that every bit of learning we do on the Crew Flight Test will improve and sharpen our experience for future crews,” said Mark Nappi, vice president and program manager, Boeing’s Starliner Program.

The crew is not pressed for time to leave the station since there are plenty of supplies in orbit, and the station’s schedule is relatively open through mid-August.

Get the latest mission updates by following the commercial crew blog, @commercial_crew on X, and commercial crew on Facebook.

NASA, Boeing Progress on Testing Starliner with Crew at Space Station

The Starliner spacecraft on NASA's Boeing Crew Flight Test approaches the International Space Station.
The Starliner spacecraft on NASA’s Boeing Crew Flight Test approaches the International Space Station while orbiting 263 miles above Quebec, Canada. NASA astronauts Butch Wilmore and Suni Williams aboard Starliner docked to the orbital outpost’s forward port on the Harmony module at 1:34 p.m. EDT on Thursday, June 6. Photo credit: NASA

Orbiting Earth as part of the nine-person crew of the International Space Station, NASA astronauts Butch Wilmore and Suni Williams continue testing Boeing’s Starliner spacecraft as part of its first flight with astronauts. The testing is part of the data collection on the Starliner system for certification by NASA for regular crewed mission to the orbital complex.

As part of NASA’s Boeing Crew Flight Test, Wilmore and Williams, along with teams on the ground, are stepping through numerous flight objectives following arrival of Starliner to the space station on June 6, including:

  • Powering the spacecraft down into a minimal power mode, which it will enter during operational missions while the crew works aboard station, and then powering it up again;
  • Conducting “safe haven” checks to show the spacecraft can support a crew with its own air and consumables during in an emergency on the station;
  • Performing a habitability study, along with astronauts Tracy Dyson and Matthew Dominick, to evaluate seating positions and other factors, such as air circulation for a four-person crew;
  • Evaluating spacesuit and seat-fits, as well as checkouts of the service module’s batteries.

Meanwhile, ground teams continue to assess and monitor Starliner’s performance and planning for return of the mission no earlier than Tuesday, June 18, pending weather and spacecraft readiness. Starliner is cleared for crew emergency return scenarios from space station, if needed, in accordance with the flight rules.

While Starliner remains docked to station, ground teams are continuing to evaluate propulsion system in-flight observations.

“Butch and Suni are doing great aboard station as ground teams continue digging into the details of Starliner’s on-orbit, rendezvous, and docked performance,” said Steve Stich, manager, NASA’s Commercial Crew Program. “We expected to do a lot of valuable learning on this test flight, and I am extremely proud of how the NASA and Boeing teams are working together to ensure we can safely execute the return portion of the mission.”

One of Starliner’s aft-facing reaction control system (RCS) thrusters, capable of about 85 pounds of thrust, remains de-selected as teams continue to evaluate its performance. Ground teams plan to fire all 28 RCS thrusters after undocking to collect additional data signatures on the service module thrusters before the hardware is expended. As part of normal operations, the service module separates from crew module on return, so NASA and Boeing will gather as much data as possible to aid in system assessments.

Teams currently are assessing what impacts, if any, five small leaks in the service module helium manifolds would have on the remainder of the mission. Engineers evaluated the helium supply based on current leak rates and determined that Starliner has plenty of margin to support the return trip from station. Only seven hours of free-flight time is needed to perform a normal end of mission, and Starliner currently has enough helium left in its tanks to support 70 hours of free flight activity following undocking. While Starliner is docked, all the manifolds are closed per normal mission operations preventing helium loss from the tanks.

Engineers also are evaluating an RCS oxidizer isolation valve in the service module that is not properly closed. Ground teams performed a successful propulsion system valve checkout on Sunday. All other oxidizer and fuel valves within the service module were cycled normally. The suspect oxidizer isolation valve was not cycled in the recent checkout. It will remain commanded closed for the remainder of the mission while ground teams continue to evaluate its data signatures. The crew module propulsion valves, which are part of an independent system that steers the capsule in the last phase of flight before landing, also were successfully cycled, and all those valves are performing as designed.

Mission managers are continuing to work through the return plan, which includes assessments of flight rationale, fault tolerance, and potential operational mitigations for the remainder of the flight. NASA and Boeing will hold a pre-departure media teleconference to provide additional updates before Starliner undocks from station.

With launch and docking already completed, the last remaining dynamic phase of the mission will come at the end of the flight test when Starliner will undock from the orbiting laboratory and then adjust its orbit to move away from the space station. The spacecraft, with Wilmore and Williams aboard, will perform a deorbit burn before entering the atmosphere and landing in the southwestern United States under parachutes and landing airbags to complete the flight.

As part of the agency’s Commercial Crew Program, the mission is the first crewed flight for the Starliner spacecraft. Learn more about the mission by following the commercial crew blog,@commercial_crew on X, and commercial crew on Facebook.

NASA’s Boeing Starliner Astronauts Enter Space Station

The seven Expedition 71 crew members gather with the two Crew Flight Test members for a team portrait aboard the space station. In the front from left are, Suni Williams, Oleg Kononenko, and Butch Wilmore. Second row from left are, Alexander Grebenkin, Tracy C. Dyson, and Mike Barratt. In the back are, Nikolai Chub, Jeanette Epps, and Matthew Dominick. Credit: NASA TV
The seven Expedition 71 crew members gather with the two Crew Flight Test members for a team portrait aboard the space station. In the front from left are, Suni Williams, Oleg Kononenko, and Butch Wilmore. Second row from left are, Alexander Grebenkin, Tracy C. Dyson, and Mike Barratt. In the back are, Nikolai Chub, Jeanette Epps, and Matthew Dominick. Photo credit: NASA Television

NASA astronauts Butch Wilmore and Suni Williams entered the International Space Station at 3:45 p.m. EDT.

The Boeing Starliner spacecraft, successfully docked to the International Space Station at 1:34 p.m. The spacecraft launched on a United Launch Alliance Atlas V rocket at 10:52 a.m. June 5 from Space Launch Complex-41 at Cape Canaveral Space Force Station in Florida.

NASA will provide coverage of the post-docking news conference at 5 p.m. on NASA+, NASA Television, the NASA app, YouTube, and the agency’s website.

As part of the agency’s Commercial Crew Program, the mission is the first crewed flight for the Starliner spacecraft. Learn more about the mission by following the commercial crew blog, @commercial_crew on X, and commercial crew on Facebook.


Learn more about station activities by following the space station blog, @space_station and @ISS_Research on X, as well as the ISS Facebook and ISS Instagram accounts.

Get weekly updates from NASA Johnson Space Center at: https://roundupreads.jsc.nasa.gov/

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