NASA, Boeing Teams “Go” for Starliner Uncrewed Return

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 view is from a window on the SpaceX Dragon Endeavour spacecraft docked to the port adjacent to the Starliner.
Boeing’s Starliner spacecraft is pictured docked to the Harmony module’s forward port at the International Space Station. Photo credit: NASA

NASA and Boeing concluded a detailed Delta-Flight Test Readiness Review on Thursday, polling “go” to proceed with undocking of the uncrewed Starliner spacecraft no earlier than 6:04 p.m. EDT on Friday, Sept. 6, from the International Space Station, pending weather and operational readiness.

After undocking, Starliner will take about six hours to reach the landing zone at White Sands Space Harbor in New Mexico. The spacecraft will touch down about 12:03 a.m. on Saturday, Sept. 7, descending under parachutes and with inflated airbags to cushion the impact. Recovery teams at the landing zone will safe and prepare the spacecraft for a return to Boeing’s Starliner factory at NASA’s Kennedy Space Center in Florida.

Following NASA’s decision on Aug. 24 to return the Starliner spacecraft uncrewed, mission managers and flight controllers updated elements of the Starliner systems with specific information for this mission that will allow the spacecraft to execute the return. The uncrewed Starliner spacecraft will perform a fully autonomous return with flight controllers at Starliner Mission Control in Houston and at Boeing Mission Control Center in Florida. Teams on the ground are able to remotely command the spacecraft if needed through the necessary maneuvers for a safe undocking, re-entry, and parachute-assisted landing in the southwest United States. NASA will host a media briefing to discuss more details about return operations, and the agency will share more on the briefing schedule and return coverage.

Starliner has previously completed a successful uncrewed entry and landing during two orbital flight tests. During one of the flight tests, the spacecraft also proved it could autonomously undock with the station safely.

As part of NASA’s Boeing Crew Flight Test, agency astronauts Butch Wilmore and Suni Williams flew aboard Starliner to the station in June. Wilmore and Williams will remain aboard the orbiting complex as part of the Expedition 71/72 crew through February 2025, when they’ll return with the agency’s Crew-9 mission.

NASA Decides to Bring Starliner Spacecraft Back to Earth Without Crew

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 view is from a window on the SpaceX Dragon Endeavour spacecraft docked to the port adjacent to the Starliner.
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 view is from a window on the SpaceX Dragon Endeavour spacecraft docked to the port adjacent to the Starliner. 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 Chart Course for Starliner Return Review

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 on Wednesday, July 3, 2024. Photo credit: NASA

Engineering and spaceflight specialists from NASA and Boeing continue data analysis ahead of a decision this week on the path forward for the Starliner spacecraft’s return from the International Space Station.

NASA’s decision on whether to return Starliner to Earth with astronauts aboard is expected no earlier than Saturday, Aug. 24 at the conclusion of an agency-level review chaired by Ken Bowersox, the associate administrator of NASA’s Space Operations Mission Directorate. The agency flight readiness review is where any formal dissents are presented and reconciled. Other agency leaders who routinely participate in launch and return readiness reviews for crewed missions include NASA’s administrator, deputy administrator, associate administrator, various agency center directors, the Flight Operations Directorate, and agency technical authorities.

NASA will host a televised news conference following the review’s conclusion to discuss the agency’s decision and next steps. More information on the news conference will be shared once confirmed. After the agency-level decision, program and flight control teams will continue preparing for Starliner’s return, including training sessions and other actions as appropriate.

Ahead of the agency-level review, NASA and Boeing are working to finalize and present flight rationale to various teams across the community and to the program control board. Engineering teams have been working to evaluate a new model that represents the thruster mechanics and is designed to more accurately predict performance during the return phase of flight. This data could help teams better understand system redundancy from undock to service module separation. Ongoing efforts to complete the new modelling, characterize spacecraft performance data, refine integrated risk assessments, and determine community recommendations will fold into the agency-level review.

Alongside the crew members of Expedition 71, NASA astronauts Butch Wilmore, commander, and Suni Williams, pilot, continue supporting a host of research, maintenance, and other activities aboard the microgravity laboratory since arriving on Starliner on June 6.

NASA Leaders Discuss Review Process for Starliner Crew Flight Test

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

NASA’s human spaceflight management team provided a media update Aug. 14 on the agency’s Boeing Crew Flight Test at the International Space Station. The group, including the Associate Administrator for Space Operations Ken Bowersox, highlighted the role safety plays as a core value at NASA and how safety guides the decision-making process for the mission.

The panel also touched on numerous aspects of the Crew Flight Test as NASA and Boeing evaluate the Starliner testing data generated over the past few weeks ahead of the agency’s Commercial Crew Program control board. NASA then plans to hold a readiness review where agency leadership will finalize the plan to return astronauts Butch Wilmore and Suni Williams from the space station. Following the readiness review, mission leadership will host a televised briefing to discuss the decision and path forward.

Listen to a full replay of the media update. Other briefing participants included:

  • Joel Montalbano, deputy associate administrator, NASA’s Space Operations Mission Directorate
  • Russ DeLoach, chief, NASA’s Office of Safety and Mission Assurance
  • NASA chief astronaut Joe Acaba
  • Emily Nelson, chief flight director, NASA’s Flight Operations Directorate

Although no final decisions have been made, teams are evaluating returning Wilmore and Williams aboard the Starliner spacecraft. In parallel, NASA also is looking more closely at the capability to return the crew as part of the agency’s SpaceX Crew-9 mission. Crew-9 will launch no earlier than Tuesday, Sept. 24, and return to Earth in February 2025.

While work continues on Earth to analyze the Starliner spacecraft and its systems, Wilmore and Williams continued their work aboard the International Space Station. Since the mission is a flight test, the crew has undergone rigorous training for any duties or issues that may arise, and the astronauts are well prepared for all situations.

The main goal of the agency’s Commercial Crew Program is two unique human spaceflight systems. Should any one system encounter an issue, NASA still has the capability to launch and return crew members to ensure safety and a continuous human presence aboard the station.

The International Space Station is the world’s leading space laboratory where researchers conduct cutting-edge research and technology development that will enable human and robotic exploration of destinations beyond low Earth orbit, including the Moon and Mars.

NASA, Boeing Continue Data Analysis for Crew Flight Test Evaluation

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 view is from a window on the SpaceX Dragon Endeavour spacecraft docked to the port adjacent to the Starliner.
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. Photo credit: NASA

NASA and Boeing teams continue analyzing data from recent ground and spacecraft testing as they evaluate the Starliner spacecraft’s propulsion system during NASA’s Boeing Crew Flight Test mission.

Teams are taking their time to analyze the results of recent docked hot-fire testing, finalize flight rationale for the spacecraft’s integrated propulsion system, and confirm system reliability ahead of Starliner’s return to Earth from the International Space Station.

Forward work for the team also includes finalizing the spacecraft’s undocking procedures and operational mitigations that could be used in flight, if needed, to build further confidence in the system. Meanwhile, Starliner ground and mission support teams are continuing to prepare for undocking by participating in integrated simulations with space station operations teams.

Following the completion of Starliner’s return planning, which is expected to continue into next week, more information will be shared about the agency’s return readiness review preparations and subsequent media briefing. As always, astronaut safety remains the top priority for both NASA and Boeing.

While engineers conduct their spacecraft studies on Earth, NASA astronauts Butch Wilmore and Suni Williams are closely following the ground team’s progress while aboard the station. The duo has integrated into the daily workload of the orbiting laboratory, giving the station a crew of nine as their mission overlaps with Expedition 71.

The astronauts worked primarily on lab upkeep aboard the orbiting outpost on Wednesday. Wilmore spent time inspecting advanced plumbing hardware then packed the life support components for return to Earth. Williams set up high-definition video gear inside the Columbus laboratory module then inspected a bar code reader and radio frequency hardware. Wilmore and Williams also partnered up and organized cargo  inside the Tranquility module before calling into a Boeing mission controllers conference.