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A SpaceX Crew Dragon capsule is bringing home two NASA astronauts who have been aboard the International Space Station for about 80 days due to problems with the Boeing Starliner spacecraft, in a stunning turn of events for the embattled aerospace giant.
The news comes after the space agency conducted a formal investigation Saturday to determine whether the Boeing Starliner vehicle is safe enough to return home with its crew, or whether SpaceX’s workhorse Crew Dragon will need to step in to save the day.
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 abruptly failing during the first portion of its first crewed test flight. Engineers spent weeks trying to better understand the issues, and Boeing said on Aug. 2 that it “remains confident” the spacecraft could return Williams and Wilmore to Earth.
However, NASA announced at a press conference on August 7 that discussions within the space agency about the safety of the Starliner capsule had evolved, prompting the federal agency to more seriously consider flying the astronauts home in a SpaceX Crew Dragon vehicle, which has flown about a dozen human space missions since 2020.
On Saturday, Nelson said NASA considered its extensive experience in spaceflight — both successful and unsuccessful — in making the decision. A poll of NASA representatives from all of the agency’s departments and research, surveillance and development centers was unanimous, agency officials said.
“We’ve made mistakes in the past: we lost two space shuttles because there wasn’t a culture of information coming forward,” Nelson said. “Space flight is risky, even at its safest and most routine. And a test flight is by its very nature neither safe nor routine.”
SpaceX is already scheduled to fly a routine mission to the International Space Station, carrying four astronauts as part of standard crew rotations aboard the orbital laboratory. But the mission, dubbed Crew-9, will now be reconfigured to carry two astronauts instead of four.
That adjustment will free up two empty seats for Williams and Wilmore to fill on the Crew 9 flight home. The astronauts will also join the Crew 9 team and be part of the official ISS expedition. With that transition, Williams and Wilmore will remain in place for another six months — the length of a routine mission to the space station.
The transfer to Crew-9 means the duo’s return will not take place until February 2025 at the earliest.
Starliner, however, will fly home empty. If the unmanned return trip goes well, NASA will face a crucial decision: whether to officially certify Starliner for human spaceflight — a step that would allow the vehicle to make routine trips to orbit — despite the fact that it didn’t complete its mission as intended.
No Boeing representatives were present at Saturday’s news conference. NASA said there was “a slight disagreement about the level of risk” compared to Boeing’s assessment, and the space agency said it needed to work on its relationship with the company.
However, Nelson added that he is “100 percent” confident that Boeing will address the issues and prepare Starliner for a crewed mission again in the future.
Boeing said in a statement Saturday that it “remains focused first and foremost on the safety of the crew and the spacecraft. We are executing the mission as directed by NASA and preparing the spacecraft for a safe and successful unmanned reentry.”
Faulty thrusters
Five of the Starliner’s 28 “reaction control thrusters” failed during the first part of Boeing’s test mission. All but one were eventually recovered.
Williams and Wilmore were expected to spend only eight days in space. However, their stay aboard the space lab has already been extended by about two months as engineers on the ground work to better understand the problems with the booster.
Officials said ground tests were able to simulate how the thrusters deteriorated in space during flight. The possible cause was heat building up inside the thrusters, which could cause insulating seals to swell and restrict the flow of fuel, Boeing said.
In addition, helium leak problems could result from seals compromised by exposure to propellant vapors, Mark Nappi, manager of Boeing’s Commercial Crew Program, said July 25.
However, NASA initially struggled to reach consensus on how these problems would affect the astronauts’ return from space, and how great a risk the problems would pose.
The uncertainty surrounding the level of risk is why the agency is turning to SpaceX and its workhorse Crew Dragon, Steve Stich, manager of NASA’s Commercial Crew Program, said Saturday.
“The bottom line with bringing Starliner back is — there was just too much uncertainty in the prediction of the thrusters,” Stich said. “It was just too risky with the crew, and so we decided to go the unmanned path forward.”
Starliner’s rocky path
NASA has repeatedly said that SpaceX’s ability to intervene highlights how the space agency deliberately designed its Commercial Crew Program — under which both Starliner and Crew Dragon were developed — so that each spacecraft could serve as a backup to the other.
“We’re in kind of a new situation here, and we have multiple options,” Ken Bowersox, deputy director of NASA’s Space Operations Mission Directorate, said Aug. 7. “That’s something we’re going to have to deal with in the future — we could end up in a situation where we have to bring a (SpaceX) Dragon crew or a (Russian) Soyuz crew back on a Starliner.
“That’s why we want multiple vehicles so we have that option,” Bowersox added.
Yet in 2014, the federal agency simultaneously funded SpaceX’s Crew Dragon and Boeing’s Starliner. Crew Dragon has been operational for four years, while the Starliner program is hundreds of millions of dollars over budget and years behind schedule.
Boeing’s development process was also plagued by missteps.
For example, the first Starliner test mission — which flew without a crew in 2019 — failed in orbit, ending its flight well short of expectations. The vehicle ultimately failed to dock with the space station as intended, and the outcome turned out to be a symptom of numerous software glitches, including a coding error that threw an internal clock off by 11 hours.
A second unmanned flight test in May 2022 revealed additional software issues, and mission teams addressed problems with some of the vehicle’s thrusters. However, the root cause of the thruster issues that plagued this manned mission was missed two years ago.
Whether the Starliner vehicle will ultimately be certified after returning to Earth is likely to be a controversial topic over what is considered the most dangerous part of the mission. The autonomous vehicle will have to use its thrusters to precisely orient itself as it falls back into Earth’s thick atmosphere. The pressure and friction are expected to heat the outside of the vehicle to about 3,000 degrees Fahrenheit (1,650 degrees Celsius).
Starliner’s parachutes must then deploy smoothly and slow the spacecraft before deploying airbags to soften the landing.
If the Starliner capsule eventually achieves certification, it could join SpaceX’s Crew Dragon to make routine trips to the space station to rotate personnel. Currently, those trips occur about every six months.
Weighing the costs
But if the spacecraft fails to achieve certification, it would be another blow to Boeing’s already badly damaged reputation. Missing the target could cost the company millions of dollars more — on top of the roughly $1.5 billion it has already lost on the Starliner program.
These cost overruns have led to recurring rumors that Boeing may not complete the Starliner program.
However, Nelson said Saturday that he recently spoke with Boeing’s new CEO, Kelly Ortberg, about the Starliner’s status.
“I told him how well Boeing worked with our team to get to this decision,” Nelson said, “and he indicated that they plan to continue working on the issues once Starliner is safely back and that we will have our redundancy and our crewed access to the space station.”
However, it is not yet clear who will bear the costs of additional testing and development needed to complete the Starliner’s development.
Nelson reiterated Saturday that the deal with Boeing is a “fixed-price contract” — meaning it is designed to be a lump sum and payments will not increase with delays as they do under alternative contracts such as “cost plus.”
Nelson added that discussions about how much Boeing is willing to pay for additional testing were not part of his conversation with the CEO.
“I don’t have the answer to that, and I don’t think we would have the answer,” Nelson said.
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