How Boeing's Starliner test flight got here and what NASA might do to bring astronauts home

It would be an awful outcome for Boeing: the two NASA astronauts who took Starliner on its inaugural crewed mission to the space station in June having to return home on a SpaceX Dragon.

It's also not a good look for NASA, a space expert said.

Already things haven't gone well for the Starliner Crewed Test Flight, and safety concerns mean NASA is weighing alternatives to bring astronauts Suni Williams and Butch Wilmore back home, including seeking a ride with SpaceX, Boeing's competitor. The Starliner test flight mission was intended as an approximately week-long visit to the International Space Station. Williams and Wilmore have already been there two months and, if they need to hitch a ride back on Dragon, their visit may last well into 2025.

There is still much teams do not understand about the issue plaguing Starliner, but the spacecraft has been besot with problems that started even before its June 5 launch.

When did things start to go wrong for Boeing's Starliner

Boeing's Starliner was contracted, along with SpaceX's Dragon, by NASA to fly astronauts to the station as part of the commercial crew program in 2014. That program was aimed at returning American rides to space after the retirement of the space shuttle. The initial contracts were for $4.82 billion for Boeing and $3.14 billion for SpaceX.

Since 2020, SpaceX has launched 13 crewed missions with a mix of NASA and private crews. Even though they had more funding from the start, Boeing has yet to complete one.

"Boeing was the frontrunner when NASA awarded the contract in 2014," said Laura Forczyk, head of Astralytical, a space industry consultation business.

"I do believe that because people assumed that Boeing had that long history in spaceflight that they didn't need that much oversight. And I think the problem's not only with Boeing, but with NASA just not giving that oversight needed ? holding Boeing accountable. Unfortunately, we're seeing the results here."

Problems with Starliner started early and kept coming

The first uncrewed test flight of Starliner (OFT-1) launched in 2019, and while it reached orbit, it failed to reach the ISS. The follow up flight test (OFT-2) launched in 2022, and while it met standards of docking to the ISS and successfully landed, multiple issues were discovered as Boeing crews inspected the spacecraft after its return.

From material that was found to be flammable to a parachute issue, Boeing teams worked to resolve these issues as the inaugural crewed flight test was continuously pushed back.

Finally, in May 2024, Boeing said it was ready to show its spacecraft could successfully carry NASA astronauts to the ISS. An issue with the Atlas V rocket prompted a scrub on the original launch day and it was then that a helium leak was discovered in the spacecraft's service module — the disposable underside of the spacecraft containing propulsion to move in space.

As the Atlas V rocket was repaired, the discovery of the leak prompted Boeing and NASA to investigate further.

In early June, teams concluded that the leak was small enough not to pose a concern, and Starliner was safe to fly atop the now-repaired Atlas V rocket. After a hiccup with the Atlas V's ground computer, Starliner carried Williams and Wilmore to space on June 5 ? only for teams to detect multiple other helium leaks in the spacecraft post-launch.

Forczyk cited those as examples that should have triggered greater concern.

"We have the fact that there have been waivers made. Flying with helium leaks and other discrepancies that probably should have been scrutinized before the Starliner mission ever flew a crew," said Forczyk.

Starliner reached the space station but the problems continued

Docking Starliner to the Space Station on June 6 proved to be an eventful second day of flight. Five thrusters in the service module shut off during the approach towards the station, prompting the astronauts to manually take control as they held Starliner at a safe distance from the ISS.

After teams performed a "hot fire" ? in which commands were sent to Starliner from the ground ? the thrusters were signaled to come back on and Starliner was able to safely dock to the orbiting outpost.

Both Boeing and NASA teams insisted that there wasn't reason for major concern. The astronauts were safely on the space station, and they'd take their time to work through the problems.

Being docked to the ISS, the helium sources were not needed and closed off.

NASA and Boeing officials continuously emphasized that the service module and its thruster are lost during reentry ? jettisoned off to expose the heat shield ? and teams needed to gather as much data as possible while the spacecraft was docked to the ISS. Meanwhile, teams worked to replicate and find a solution to the issue at the White Sands Test Facility in New Mexico.

Meanwhile, the return date for the astronauts kept moving from June to July to August.

Starliner thruster: what's happening

What's going on with the thrusters?

To return Starliner to Earth, the thrusters need to fire correctly at the right time to get the crew safely out of orbit.

"Clearly, you need to have thrusters to be able to position your spacecraft, to move away from the space station, to get into the position to safely reenter the Earth's atmosphere," said Don Platt, associate professor of space systems at Florida Tech.

"They claim just doing a rocket burn, they can probably make it home, but they don't know where'd they land," said Platt.

The problem lies with the propulsion system inside the service module.

"It sounds as if they've experienced a different amount of heating than expected with some of these thrusters, and had some affected things like valves that control the flow of propellant to the thrusters. So sometimes those valves will leak or not open all the way based on the amount of heat they are experiencing," said Platt.

Platt explained that the valves for these thrusters are comparable to fuel injectors in a car. They simply open and close to feed the propellant into the combustion chamber ? the end result being thrust (power).

Part of the challenge for Boeing teams is that they can't exactly replicate what the spacecraft is experiencing in space. Platt said that heat is not just created from the thruster itself, but from the Sun.

Backing away from the ISS will not be the issue ? it is the deorbit burn which has many at NASA concerned. Dana Weigel, International Space Station (ISS) Program Manager, told reporters on Wednesday that the ISS is not in any danger should Starliner's thrusters malfunction upon undocking.

"The worst case scenario would be ... if they could not use the thrusters at all, and they really didn't have control ? I think they would definitely have some level of thrust to back away from the station or they wouldn't even try. They've done the on-orbit hot fire testing at the International Space Station already," explain Platt.

The problem would be if they could "not properly orient themselves in perspective to the Earth's atmosphere."

According to the Wednesday NASA press briefing, there is some concern that Starliner could land way off its target landing spot in New Mexico. This situation would cause the astronauts to have to await search and rescue.

How will NASA bring the astronauts home

For the first time last week, NASA said they are exploring alternative options to bring the astronauts home. No decision has been made.

If not on Starliner, Williams and Wilmore might need to wait to return on the Crew-9 SpaceX Dragon in February. In this situation, NASA would only send two astronauts on the Crew-9 mission slated to launch next month with Wilmore and Williams joining in the six-month expedition. That would bump two of the already named four person crew off the mission.

Then Williams and Wilmore would join that mission and return when it completed its time on the station, currently set for February 2025.

NASA has been in talks with SpaceX on this alternative, and SpaceX suits for Williams and Wilmore would be brought up for their return if this is the option selected.

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"If Starliner does not bring back those astronauts, then it raises concern about whether the Starliner program will still work, whether or not there still needs to be another uncrewed mission before certification of the crewed craft, whether or not there needs to be (another) demo crew mission. There's just a lot of questions up in the air," said Forczyk.

There could be questions, too, about what NASA got for all of the money it spent on the Starliner. Plus, if Boeing were to repeat a test flight, it would be on their dime ? as was seen with OFT-2 in 2022, Boeing's repeat of the uncrewed flight test.

Could SpaceX just send up another Dragon specifically for Starliner crew?

Meanwhile, NASA is left in a difficult situation.

"It's not like it's a panic situation with the astronauts onboard, it's just that they don't have time in terms of the way the logistics of ISS works and the different missions that are going on. You do have Crew-9 to worry about. You do have Axiom-4 to worry about. The next Soyuz mission....you have all these things to balance," said Forczyk.

It's not immediately clear why NASA hasn't considered an option of asking SpaceX to fast track a Crew Dragon up to the station to bring the Starliner astronauts home. But that's not on the table.

"The team did not entertain the option of a new Dragon mission because the options for modifying an existing mission were sufficient in this case. As was noted in the media call, the CFT astronauts, Butch and Suni, can be folded into the Crew-9 complement if that decision is made and they can fulfill the work of that increment (Expedition 71/72) on the ISS," wrote NASA public affairs representative, Steve Siceloff, in an email to FLORIDA TODAY.

During that August 7 media called, Steve Stich, program manager for NASA's Commercial Crew Program said, “From the very beginning, we liked the option of modifying Crew-9 or Crew-8. We looked at both of those and bringing them back ... It just didn't make sense to go ahead and accelerate a flight (with) SpaceX to return Butch and Suni earlier.”

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What's next for astronauts and Starliner

While bringing Williams and Wilmore back on Starliner remains a possibility, whatever option NASA takes will impact space station operations.

Should NASA choose to bring the astronauts back with Crew-9 on a SpaceX Dragon, Starliner will have to be programed by teams on the ground to remotely undock without a crew. It is unclear at this time what will become of Starliner if this is decided.

However, a decision must be made soon. Starliner would need to undock before the Crew-9 Dragon launches in order to free the docking space ? as the space station has limited parking.

Former astronaut, Clayton Anderson, said he believes Williams and Wilmore have faith in the decisions being made. He replied to FLORIDA TODAY in a conversation on X (formerly Twitter), saying, "They want as much info on all discussions as possible. They are pros and will accept whatever decision comes, but they are also test pilots, and confident that their vehicle is safe."

Brooke Edwards is a Space Reporter for Florida Today. Contact her at [email protected] or on X: @brookeofstars.

This article originally appeared on Florida Today: Starliner's troubles continue as NASA weights options for its crew