But what if it was not safe to come home, either?
"I don't know that we can come back to Earth at that point," Wilmore said in an interview. "I don't know if we can. And matter of fact, I'm thinking we probably can't."
Starliner astronauts meet with the media
On Monday, for the first time since they returned to Earth on a Crew Dragon vehicle two weeks ago, Wilmore and Williams participated in a news conference at Johnson Space Center in Houston. Afterward, they spent hours conducting short, 10-minute interviews with reporters from around the world, describing their mission. I spoke with both of them.
Many of the questions concerned the politically messy end of the mission, in which the Trump White House claimed it had rescued the astronauts after they were stranded by the Biden administration. This was not true, but it is also not a question that active astronauts are going to answer. They have too much respect for the agency and the White House that appoints its leadership. They are trained not to speak out of school. As Wilmore said repeatedly on Monday, "I can't speak to any of that. Nor would I."
So when Ars met with Wilmore at the end of the day—it was his final interview, scheduled for 4:55 to 5:05 pm in a small studio at Johnson Space Center—politics was not on the menu. Instead, I wanted to know the real story, the heretofore untold story of what it was really like to fly Starliner. After all, the problems with the spacecraft's propulsion system precipitated all the other events—the decision to fly Starliner home without crew, the reshuffling of the Crew-9 mission, and their recent return in March after nine months in space.
I have known Wilmore a bit for more than a decade. I was privileged to see his launch on a Soyuz rocket from Kazakhstan in 2014, alongside his family. We both are about to become empty nesters, with daughters who are seniors in high school, soon to go off to college. Perhaps because of this, Wilmore felt comfortable sharing his experiences and anxieties from the flight. We blew through the 10-minute interview slot and ended up talking for nearly half an hour.
It's a hell of a story.
Launch and a cold night
Boeing's Starliner spacecraft faced multiple delays before the vehicle's first crewed mission, carrying NASA astronauts Butch Wilmore and Suni Williams launched on June 5, 2024. These included a faulty valve on the Atlas V rocket's upper stage, and then a helium leak inside Boeing's Starliner spacecraft.
The valve issue, in early May, stood the mission down long enough that Wilmore asked to fly back to Houston for additional time in a flight simulator to keep his skills fresh. Finally, with fine weather, the Starliner Crew Flight Test took off from Cape Canaveral, Florida. It marked the first human launch on the Atlas V rocket, which had a new Centaur upper stage with two engines.
Sunita "Suni" Williams: "Oh man, the launch was awesome. Both of us looked at each other like, 'Wow, this is going just perfectly.' So the ride to space and the orbit insertion burn, all perfect."
Barry "Butch" Wilmore: "In simulations, there's always a deviation. Little deviations in your trajectory. And during the launch on Shuttle STS-129 many years ago, and Soyuz, there's the similar type of deviations that you see in this trajectory. I mean, it's always correcting back. But this ULA Atlas was dead on the center. I mean, it was exactly in the crosshairs, all the way. It was much different than what I'd expected or experienced in the past. It was exhilarating. It was fantastic. Yeah, it really was. The dual-engine Centaur did have a surge. I'm not sure ULA knew about it, but it was obvious to us. We were the first to ride it. Initially we asked, 'Should that be doing that? This surging?' But after a while, it was kind of soothing. And again, we were flying right down the middle."
After Starliner separated from the Atlas V rocket, Williams and Wilmore performed several maneuvering tests and put the vehicle through its paces. Starliner performed exceptionally well during these initial tests on day one.
Wilmore: "The precision, the ability to control to the exact point that I wanted, was great. There was very little, almost imperceptible cross-control. I've never given a handling qualities rating of "one," which was part of a measurement system. To take a qualitative test and make a quantitative assessment. I've never given a one, ever, in any test I've ever done, because nothing's ever deserved a one. Boy, I was tempted in some of the tests we did. I didn't give a one, but it was pretty amazing."
Following these tests, the crew attempted to sleep for several hours ahead of their all-important approach and docking with the International Space Station on the flight's second day. More so even than launch or landing, the most challenging part of this mission, which would stress Starliner's handling capabilities as well as its navigation system, would come as it approached the orbiting laboratory.
Williams: "The night that we spent there in the spacecraft, it was a little chilly. We had traded off some of our clothes to bring up some equipment up to the space station. So I had this small T-shirt thing, long-sleeve T-shirt, and I was like, 'Oh my gosh, I'm cold.' Butch is like, 'I'm cold, too.' So, we ended up actually putting our boots on, and then I put my spacesuit on. And then he's like, maybe I want mine, too. So we both actually got in our spacesuits. It might just be because there were two people in there."
Starliner was designed to fly four people to the International Space Station for six-month stays in orbit. But for this initial test flight, there were just two people, which meant less body heat. Wilmore estimated that it was about 50° Fahrenheit in the cabin.
Wilmore: "It was definitely low 50s, if not cooler. When you're hustling and bustling, and doing things, all the tests we were doing after launch, we didn't notice it until we slowed down. We purposely didn't take sleeping bags. I was just going to bungee myself to the bulkhead. I had a sweatshirt and some sweatpants, and I thought, I'm going to be fine. No, it was frigid. And I even got inside my space suit, put the boots on and everything, gloves, the whole thing. And it was still cold."
Time to dock with the space station
After a few hours of fitful sleep, Wilmore decided to get up and start working to get his blood pumping. He reviewed the flight plan and knew it was going to be a big day. Wilmore had been concerned about the performance of the vehicle's reaction control system thrusters. There are 28 of them. Around the perimeter of Starliner's service module, at the aft of the vehicle, there are four "doghouses" equally spaced around the vehicle.
Each of these doghouses contains seven small thrusters for maneuvering. In each doghouse, two thrusters are aft-facing, two are forward-facing, and three are in different radial directions (see an image of a doghouse, with the cover removed, here). For docking, these thrusters are essential. There had been some problems with their performance during an uncrewed flight test to the space station in May 2022, and Wilmore had been concerned those issues might crop up again.
Wilmore: "Before the flight we had a meeting with a lot of the senior Boeing executives, including the chief engineer. [This was Naveed Hussain, chief engineer for Boeing's Defense, Space, and Security division.] Naveed asked me what is my biggest concern? And I said the thrusters and the valves because we'd had failures on the OFT missions. You don't get the hardware back. (Starliner's service module is jettisoned before the crew capsule returns from orbit). So you're just looking at data and engineering judgment to say, 'OK, it must've been FOD,' (foreign object debris) or whatever the various issues they had. And I said that's what concerns me the most. Because in my mind, I'm thinking, 'If we lost thrusters, we could be in a situation where we're in space and can't control it.' That's what I was thinking. And oh my, what happened? We lost the first thruster."
When vehicles approach the space station, they use two imaginary lines to help guide their approach. These are the R-bar, which is a line connecting the space station to the center of Earth. The "R" stands for radius. Then there is the V-bar, which is the velocity vector of the space station. Due to thruster issues, as Starliner neared the V-bar about 260 meters (850 feet) from the space station, Wilmore had to take manual control of the vehicle.
Wilmore: "As we get closer to the V-bar, we lose our second thruster. So now we're single fault tolerance for the loss of 6DOF control. You understand that?"
Here things get a little more complicated if you've never piloted anything. When Wilmore refers to 6DOF control, he means six degrees of freedom—that is, the six different movements possible in three-dimensional space: forward/back, up/down, left/right, yaw, pitch, and roll. With Starliner's four doghouses and their various thrusters, a pilot is able to control the spacecraft's movement across these six degrees of freedom. But as Starliner got to within a few hundred meters of the station, a second thruster failed. The condition of being "single fault" tolerant means that the vehicle could sustain just one more thruster failure before being at risk of losing full control of Starliner's movement. This would necessitate a mandatory abort of the docking attempt.
Wilmore: "We're single fault tolerant, and I'm thinking, 'Wow, we're supposed to leave the space station.' Because I know the flight rules. I did not know that the flight directors were already in discussions about waiving the flight rule because we've lost two thrusters. We didn't know why. They just dropped."
After Starliner separated from the Atlas V rocket, Williams and Wilmore performed several maneuvering tests and put the vehicle through its paces. Starliner performed exceptionally well during these initial tests on day one.
Wilmore: "The precision, the ability to control to the exact point that I wanted, was great. There was very little, almost imperceptible cross-control. I've never given a handling qualities rating of "one," which was part of a measurement system. To take a qualitative test and make a quantitative assessment. I've never given a one, ever, in any test I've ever done, because nothing's ever deserved a one. Boy, I was tempted in some of the tests we did. I didn't give a one, but it was pretty amazing."
Following these tests, the crew attempted to sleep for several hours ahead of their all-important approach and docking with the International Space Station on the flight's second day. More so even than launch or landing, the most challenging part of this mission, which would stress Starliner's handling capabilities as well as its navigation system, would come as it approached the orbiting laboratory.
Williams: "The night that we spent there in the spacecraft, it was a little chilly. We had traded off some of our clothes to bring up some equipment up to the space station. So I had this small T-shirt thing, long-sleeve T-shirt, and I was like, 'Oh my gosh, I'm cold.' Butch is like, 'I'm cold, too.' So, we ended up actually putting our boots on, and then I put my spacesuit on. And then he's like, maybe I want mine, too. So we both actually got in our spacesuits. It might just be because there were two people in there."
Starliner was designed to fly four people to the International Space Station for six-month stays in orbit. But for this initial test flight, there were just two people, which meant less body heat. Wilmore estimated that it was about 50° Fahrenheit in the cabin.
Wilmore: "It was definitely low 50s, if not cooler. When you're hustling and bustling, and doing things, all the tests we were doing after launch, we didn't notice it until we slowed down. We purposely didn't take sleeping bags. I was just going to bungee myself to the bulkhead. I had a sweatshirt and some sweatpants, and I thought, I'm going to be fine. No, it was frigid. And I even got inside my space suit, put the boots on and everything, gloves, the whole thing. And it was still cold."
Time to dock with the space station
After a few hours of fitful sleep, Wilmore decided to get up and start working to get his blood pumping. He reviewed the flight plan and knew it was going to be a big day. Wilmore had been concerned about the performance of the vehicle's reaction control system thrusters. There are 28 of them. Around the perimeter of Starliner's service module, at the aft of the vehicle, there are four "doghouses" equally spaced around the vehicle.
Each of these doghouses contains seven small thrusters for maneuvering. In each doghouse, two thrusters are aft-facing, two are forward-facing, and three are in different radial directions (see an image of a doghouse, with the cover removed, here). For docking, these thrusters are essential. There had been some problems with their performance during an uncrewed flight test to the space station in May 2022, and Wilmore had been concerned those issues might crop up again.
Wilmore: "Before the flight we had a meeting with a lot of the senior Boeing executives, including the chief engineer. [This was Naveed Hussain, chief engineer for Boeing's Defense, Space, and Security division.] Naveed asked me what is my biggest concern? And I said the thrusters and the valves because we'd had failures on the OFT missions. You don't get the hardware back. (Starliner's service module is jettisoned before the crew capsule returns from orbit). So you're just looking at data and engineering judgment to say, 'OK, it must've been FOD,' (foreign object debris) or whatever the various issues they had. And I said that's what concerns me the most. Because in my mind, I'm thinking, 'If we lost thrusters, we could be in a situation where we're in space and can't control it.' That's what I was thinking. And oh my, what happened? We lost the first thruster."
When vehicles approach the space station, they use two imaginary lines to help guide their approach. These are the R-bar, which is a line connecting the space station to the center of Earth. The "R" stands for radius. Then there is the V-bar, which is the velocity vector of the space station. Due to thruster issues, as Starliner neared the V-bar about 260 meters (850 feet) from the space station, Wilmore had to take manual control of the vehicle.
Wilmore: "As we get closer to the V-bar, we lose our second thruster. So now we're single fault tolerance for the loss of 6DOF control. You understand that?"
Here things get a little more complicated if you've never piloted anything. When Wilmore refers to 6DOF control, he means six degrees of freedom—that is, the six different movements possible in three-dimensional space: forward/back, up/down, left/right, yaw, pitch, and roll. With Starliner's four doghouses and their various thrusters, a pilot is able to control the spacecraft's movement across these six degrees of freedom. But as Starliner got to within a few hundred meters of the station, a second thruster failed. The condition of being "single fault" tolerant means that the vehicle could sustain just one more thruster failure before being at risk of losing full control of Starliner's movement. This would necessitate a mandatory abort of the docking attempt.
Wilmore: "We're single fault tolerant, and I'm thinking, 'Wow, we're supposed to leave the space station.' Because I know the flight rules. I did not know that the flight directors were already in discussions about waiving the flight rule because we've lost two thrusters. We didn't know why. They just dropped."
The heroes in Mission Control
As part of the Commercial Crew program, the two companies providing transportation services for NASA, SpaceX, and Boeing, got to decide who would fly their spacecraft. SpaceX chose to operate its Dragon vehicles out of a control center at the company's headquarters in Hawthorne, California. Boeing chose to contract with NASA's Mission Control at Johnson Space Center in Houston to fly Starliner. So at this point, the vehicle is under the purview of a Flight Director named Ed Van Cise. This was the capstone mission of his 15-year career as a NASA flight director.
Wilmore: "Thankfully, these folks are heroes. And please print this. What do heroes look like? Well, heroes put their tank on and they run into a fiery building and pull people out of it. That's a hero. Heroes also sit in their cubicle for decades studying their systems, and knowing their systems front and back. And when there is no time to assess a situation and go and talk to people and ask, 'What do you think?' they know their system so well they come up with a plan on the fly. That is a hero. And there are several of them in Mission Control."
From the outside, as Starliner approached the space station last June, we knew little of this. By following NASA's webcast of the docking, it was clear there were some thruster issues and that Wilmore had to take manual control. But we did not know that in the final minutes before docking, NASA waived the flight rules about loss of thrusters. According to Wilmore and Williams, the drama was only beginning at this point.
by Eric Berger, Ars Technica | Read more:
Image: NASA
