Veteran astronauts and Navy test pilots Suni Williams and Butch Wilmore will wave goodbye to the ride that brought them to the International Space Station nearly three months ago when the problem-plagued Boeing Starliner space capsule heads back to Earth — without a crew — on a flight now set for Friday evening.
NASA announced Starliner is scheduled to autonomously undock from the space station at approximately 8:04 p.m. MDT Friday, Sept. 6, to begin the journey home, weather conditions permitting. NASA and Boeing said they are targeting a landing for approximately 12:03 a.m., Saturday, Sept. 7, on the grounds of the White Sands Missile Range in New Mexico.
NASA said it will provide live coverage of Starliner’s return with streaming connections available on NASA+, the NASA app and the agency’s website.
Early on in Starliner’s mission, NASA Administrator Bill Nelson said Utah’s Dugway Proving Grounds was the “primary site” for landing the Boeing capsule.
The path to Starliner’s empty return
Boeing’s Starliner space capsule launched in early June on a test flight mission originally planned to last about a week. Last week, NASA announced its decision to keep Williams and Wilmore aboard the ISS until next year, deeming that putting the astronauts aboard Starliner for its return to Earth was too risky.
Previous reports from NASA and Boeing detailed that five of 28 maneuvering thrusters failed to perform as expected during Starliner’s docking at the ISS on June 6. Engineers also identified five small helium leaks, some of which were detected before the spacecraft launched. Helium is used in the capsule’s thruster firing procedure. Since then, engineering teams have been scrambling to identify the underlying issues with the thrusters, including reviewing massive amounts of data, conducting flight and ground testing, hosting independent reviews with agency propulsion experts and developing various return contingency plans, NASA said. The thrusters are critical for maneuvering and positioning the spacecraft.
But ultimately NASA decided that ongoing uncertainty and a lack of concurrence among engineers and other experts “does not meet the agency’s safety and performance requirements for human spaceflight, thus prompting NASA leadership to move the astronauts to the (SpaceX Dragon) Crew-9 mission.”
“Spaceflight is risky, even at its safest and most routine,” said NASA Administrator Bill Nelson in an Aug. 24 press release. “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. I’m grateful to both the NASA and Boeing teams for all their incredible and detailed work.”
Designed for pilotless flight
Boeing’s Starliner capsule is designed for autonomous flight and has previously completed two uncrewed test flights. Since the decision to send Starliner back empty, NASA has been working with Boeing engineers to update Starliner’s systems for the autonomous return flight. The ship needs to vacate its dock at the ISS before late September, when the SpaceX Dragon Crew-9 flight is scheduled to arrive.
“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 last week. “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.”
Last month, in anticipation of the possibility of an autonomous return flight for Starliner, NASA announced the SpaceX Crew 9 mission to the ISS, originally scheduled to launch Aug. 18, had been pushed back more than a month to potentially reconfigure that flight to make room for passengers when it returns next winter. Those changes include trimming Crew 9′s original four-astronaut crew to just two to make room for the stranded Starliner crew. The flight will also carry necessary equipment to the ISS, like new spacesuits, for Williams and Wilmore to join the Dragon crew.
How those decisions and mission outcomes impact Boeing’s Starliner program and the spacecraft’s future viability as a reliable vehicle remains to be seen.