NASA Still Deciding If Butch and Suni Will Come Home on Starliner

NASA officials said today they expect to decide in mid-August whether Boeing’s Starliner capsule will bring two NASA astronauts back to Earth or return empty. The continued uncertainty is driven in part by the fact that for the first time the agency actually has the option to return them on a different vehicle, SpaceX’s Crew Dragon. Redundancy was exactly the reason NASA wanted two commercial crew providers. Now they are weighing risks differently and decisions can take longer than expected.

Starliner lifted off on its Crew Flight Test on June 5 with NASA astronauts Butch Wilmore and Suni Williams. As NASA repeatedly stresses this is a test flight and encountering problems is no surprise. Butch and Suni, experienced astronauts and Navy test pilots, are trained to deal with contingencies.

And contingencies there have been, extending what was to have been an eight-day visit to the International Space Station to one that is nine weeks and counting.

The two issues of primary concern are that during the one-day trip from the launch pad to the ISS, five of the 28 Reaction Control System (RCS) thrusters went offline and four more helium leaks occurred in addition to one discovered before launch.

NASA and Boeing are comfortable that the helium leaks are stable and there is more than enough helium — 10 times more — to finish the mission.

As for the thrusters, four of the five came back online before Starliner docked to the ISS, but the question is what caused them to be “deselected” by software in the first place.

NASA and Boeing did tests on a similar thruster at NASA’s White Sands, New Mexico test facility and concluded that Teflon seals in a poppet valve deformed probably due to overheating and restricted propellant flow.

On July 29, NASA and Boeing conducted “hot-fire” tests of the 27 functioning RCS thrusters on Starliner as it was docked to the ISS. Today NASA said the surprise was they performed better than expected. If the Teflon seals had deformed, how could they now be fine?

That is the question styming a decision about whether Starliner is capable of bringing Butch and Suni home safely or if instead they should come home on a SpaceX Crew Dragon. NASA continues to insist they could bring them home on Starliner if there was an emergency like the ISS itself was threatened — that’s one risk calculation — but otherwise they want more data.

Ken Bowersox, a former astronaut who now heads NASA’s Space Operations Mission Directorate, said the July 29 tests added to the debate. The thrusters performed as though they were not obstructed and NASA wants to understand the physics that could make that happen. Otherwise they’ve misunderstood the problem.

Starliner and SpaceX were awarded contracts in 2014 to build commercial crew space transportation systems to ferry astronauts to and from the ISS. SpaceX’s Crew Dragon has been doing that twice a year since 2020. That means there’s another way for Butch and Suni to come home, on a Crew Dragon, with Starliner returning to Earth autonomously with no crew aboard.

After the July 29 hotfire tests, “our chances of an uncrewed Starliner return have increased a little bit,” Bowersox said.

ISS crews rotate on roughly 6-month schedules. Three members of the seven-person international crew come and go on Russian Soyuz spacecraft and four on SpaceX’s Crew Dragon. SpaceX’s ninth operational crew rotation mission, Crew-9, was targeted for August 18, but NASA just delayed it to September 24 because of the uncertainty about how and when Starliner will return.

The U.S. segment of ISS has only two docking ports (plus two for berthing). Starliner is at one and the Crew-8 Crew Dragon at the other. NASA likes to have a 5-day handover from one crew to another so Starliner must depart and free up that port before Crew-9 arrives.

The question is whether Starliner has Butch and Suni aboard when it departs or if it’s empty. NASA confirmed today it is considering launching Crew-9 with only two crew members instead of four, leaving the other two seats for Butch and Suni to return with them in February. They declined to say which two of the four would be the ones to go to ISS and which would have to wait for another assignment if — and it’s still an if — that’s the decision.

Dana Weigel, NASA ISS Program Manager, said Butch and Suni were well aware of the possibility they could remain aboard the ISS for several months instead of eight days before they launched. Both have spent long-duration missions on the ISS before and are very familiar with the maintenance and scientific activities conducted there.  Over the last nine weeks, NASA says they have completely integrated with other ISS crew members.

No decision has been made on when they will return or whether it will be on Starliner or Crew Dragon. Having multiple options “gives us a lot more to talk about” and “reasonable people could pick either path,” Bowersox said.

“What we’re trying to do is reduce that uncertainty, see if we can drive some more consensus amongst our team. At the same time getting more serious about evaluating our other options. It’s been really great to watch our team working, our Boeing team, our NASA team, the way people are speaking up, the way we’re hearing different voices, different thoughts on how critical different factors are in the decision. I think it’s been very healthy. I have to admit that sometimes when we get disagreement it’s not fun, it can be painful having those discussions, but it’s what makes us a good organization and it’s what will get us to a good decision as we approach that point here in the future. And I don’t think we’re too far away from making that call.” — Ken Bowersox

Bowersox will lead a Flight Readiness Review when the time is right to decide the path forward, but NASA Administrator Bill Nelson is the ultimate decision maker. He told Ars Technica earlier this week that he’ll be making the final decision.

As a member of the House of Representatives, Nelson flew on Space Shuttle mission 61-C in January 1986, which landed 10 days before the Challenger tragedy that killed NASA astronauts Dick Scobee, Mike Smith, Ron McNair, Judy Resnik, and Ellison Onizuka, Hughes Aircraft payload specialist Greg Jarvis, and Teacher-in-Space Christa McAuliffe.

Boeing’s Vice President and Program Manager for Commercial Crew Mark Nappi has participated in previous media telecons about Starliner, but not today. Bowersox said he wanted to use this briefing to give “the NASA team’s point of view and all the complicated issues on ISS.”  For its part, Boeing issued a statement on Friday pointing to all the tests they completed for Starliner and expressing confidence in its ability to return Butch and Suni safely to Earth.