Boeing Starliner astronauts: NASA set to decide how they’ll return

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The fate of two NASA astronauts — who have been in limbo aboard the International Space Station for about 80 days because of issues plaguing their Boeing Starliner spacecraft — may soon become clear.

The space agency said it will hold a formal review on Saturday to determine whether it will deem Boeing’s Starliner vehicle safe enough to return home with its crew — or if SpaceX’s workhorse Crew Dragon spacecraft will have to step in to save the day.

NASA said it will share its decision after the review concludes on Saturday. A news conference was scheduled for 1 p.m. ET, or “about an hour” after the review is over, according to an email from NASA. The space agency routinely delays news conferences, however, if discussions take longer than expected.

The Starliner vehicle, which carried astronauts Suni Williams and Butch Wilmore to the space station in early June, suffered setbacks with helium leaks and thrusters that abruptly stopped working on the initial leg of its first crewed test flight. Engineers spent weeks attempting to better understand the issues, and Boeing said as recently as August 2 that its “confidence remains high” that the spacecraft would be able to return Williams and Wilmore to Earth.

NASA revealed during an August 7 news briefing, however, that discussions within the space agency about the Starliner capsule’s safety had evolved — prompting the federal agency to more seriously consider flying the astronauts home on a SpaceX Crew Dragon vehicle, which has flown about a dozen crewed mission to space since 2020.

SpaceX had already been slated to execute a routine mission to the International Space Station, carrying four astronauts as part of standard crew rotations aboard the orbiting laboratory. But the mission, called Crew-9, could now be reconfigured to carry two astronauts on board instead of four.

That adjustment would leave two empty seats for Williams and Wilmore to occupy on the Crew-9 flight home. The astronauts would also officially join the Crew-9 team, becoming part of the official expedition. With that transition, Williams and Wilmore would remain on-site for an additional six months — the length of a routine mission to the space station.

The reassignment to Crew-9 could push the duo’s return to February 2025 at the earliest.

Starliner, in that scenario, would fly home empty. And NASA would have to decide whether the data Starliner did gather on its mission is enough to give the space agency the confidence to officially certify Starliner for human spaceflight — a step that would set up the vehicle to make routine trips to orbit.

Five of the Starliner’s 28 “reaction control thrusters” quit working during the first stretch of Boeing’s test mission. All but one were eventually recovered.

And while Williams and Wilmore expected to spend only eight days in space, their stay aboard the orbiting lab has already been extended by roughly two months as engineers on the ground have worked to better understand the thruster problems.

Officials said they were able to recreate how the thrusters in space deteriorated during flight with tests on the ground. The possible root cause was heat building up inside the thrusters that may be causing insulating seals to bulge, restricting the flow of propellant, Boeing said.

Separately, issues with helium leaks may be the result of seals that have become degraded because of exposure to propellant vapor, according to comments from Mark Nappi, Boeing’s Commercial Crew Program manager, on July 25.

Still, NASA has struggled to reach a consensus on how those issues might affect the astronauts’ return from space — and how much risk the problems would pose.

The uncertainty surrounding the level of risk is why the agency could turn to SpaceX and its workhorse Crew Dragon vessel to step in.

NASA has repeatedly said that SpaceX’s potential to step in highlights how the space agency intentionally designed its Commercial Crew Program — under which both Starliner and Crew Dragon were developed — to allow each spacecraft to serve as backup for the other.

“We’re in a kind of a new situation here and that we’ve got multiple options,” said Ken Bowersox, associate administrator for NASA’s Space Operations Mission Directorate, on August 7. “That’s something that we’re going to have to deal with in the future — we could find ourselves in a situation where we need to bring a (SpaceX) Dragon crew or a (Russian) Soyuz crew back on a Starliner.

“That’s why we want multiple vehicles — so that we have that option,” Bowersox added.

Still, the federal agency funded SpaceX’s Crew Dragon and Boeing’s Starliner at the same time in 2014. Crew Dragon has already been in operation for four years, while the Starliner program is hundreds of millions of dollars over budget and years behind schedule.

Boeing’s development process has also been plagued by missteps.

For example, the first Starliner test mission — flown in 2019 without a crew — misfired in orbit and cut the flight far short of expectations. The vehicle did not ultimately dock with the space station as intended, and the outcome was revealed to be a symptom of myriad software problems, including a coding error that set an internal clock off by 11 hours.

A second uncrewed flight test in May 2022 uncovered additional software issues, and the mission teams addressed problems with some of the vehicle’s thrusters. However, the root cause of the thruster trouble plaguing this crewed mission was missed two years ago.

Whether the Starliner vehicle ultimately becomes certified after its return to Earth will likely become a controversial issue, especially if the spacecraft does not bring Williams and Wilmore home and does not perform as intended during reentry — which is considered to be the most dangerous leg of the mission. The autonomous vehicle will have to use its thrusters to precisely orient itself as it plunges back into Earth’s thick atmosphere. The pressure and friction are expected to heat the vehicle’s exterior to roughly 3,000 degrees Fahrenheit (1,650 degrees Celsius).

Starliner’s parachutes must then deploy without issue and slow down the spacecraft before triggering airbags to expand and cushion the landing.

If the Starliner capsule is ultimately certified, it could join SpaceX’s Crew Dragon in making routine trips to the space station to rotate staff. Currently, those trips are occurring roughly every six months.

And if the spacecraft is denied certification, it would mark yet another blow to Boeing’s already badly damaged reputation. Missing the mark could cost the company many millions of additional dollars — on top of the roughly $1.5 billion the company has already recorded in losses on the Starliner program.