SOPHIE BUSHWICK: When NASA retired its space shuttle program, in 2011, the agency had to find a new way to deliver astronauts and supplies to the International Space Station. Russia’s Soyuz program filled that need since then, but NASA has wanted a more local solution for a while. So they started awarding contracts to private US companies who could act as space taxis, including SpaceX with its Dragon capsule and Boeing with its Starliner capsule. The Starliner will fly on United Launch Alliance’s Atlas V rocket, but unlike SpaceX, Boeing has yet to fly humans in its spacecraft, which it plans to do no earlier than next Friday.

Here to tell us about Boeing’s rocky road to the Space Station is my guest, Brendan Byrne, Assistant News Director at Central Florida Public Media, where he covers space news. Brendan, welcome to Science Friday.

BRENDAN BYRNE: Hey. Thanks for having me.

SOPHIE BUSHWICK: And before we get to the recent updates, what is Starliner, and how does it compare to something like SpaceX’s Dragon?

BRENDAN BYRNE: Well, they’re both very similar. Listeners may be very familiar with the interior of SpaceX’s Dragon capsule. They’ve flown eight or nine missions at this point. They’re very sleek, with some cool touch screens and all that, but Boeing’s Starliner is old school looking on the inside. It’s got handles and switches and displays, but it is designed just like SpaceX’s Crew Dragon capsule to fly autonomously, so it can take the crew all by itself to the International Space Station.

SOPHIE BUSHWICK: And like you mentioned, SpaceX’s Dragon capsule has already flown some missions, and Boeing’s Starliner hasn’t. So why is Boeing so far behind SpaceX?

BRENDAN BYRNE: Yeah, that’s right. The rocky path to the International Space Station began in 2019. So it was flying an uncrewed test mission to prove to NASA that it could get to the International Space Station, before it put its astronauts on it, and a software issue prevented that from happening.

They worked out some of the coding issues and went to retry it again, in 2020. I should add, this was on Boeing’s dime. NASA didn’t pay for this refly.

It was considered a success, and leading up to this crewed mission that’s happening in a few days, last year, engineers discovered a few other issues from that second test flight. They found that the lines to the parachutes weren’t strong enough, and they also found the tape that was used to wrap the hundreds of feet of wire throughout the spacecraft were flammable. So that delayed this launch even further, then certified late last month, the capsule to fly this crewed mission that we are expecting to happen very shortly.

SOPHIE BUSHWICK: And who is going to be on this crewed mission?

BRENDAN BYRNE: Two seasoned NASA astronauts– you’ve got Butch Wilmore as the commander and Suni Williams is the pilot. They are both Navy test pilots before they became NASA astronauts. They have lived and worked on the International Space Station.

I should add, they are very, very excited to get back. Butch and Sunny were asked about what they missed the most about being in space, and Butch said it was the food. He can’t wait to get back to the International Space Station.

SOPHIE BUSHWICK: That’s not what I expected to hear.

BRENDAN BYRNE: He can’t wait to get there. There’s apparently a chocolate pudding up there that he cannot wait to dig his spoon into.

SOPHIE BUSHWICK: And they were actually supposed to launch this week, but that’s not happening. So why weren’t they able to launch on Monday?

BRENDAN BYRNE: So what kept the mission grounded was actually found in the rocket that is taking them up, a separate company United Launch Alliance. Well, there was a valve on the upper stage that regulates the pressure of the liquid oxygen that is used as a fuel. Well, it was opening and closing very, very rapidly, and we learned later that this particular valve is rated for up to 200,000 of these oscillations, and they determined that it actually had exceeded that limit. So what they have to do now is to replace that valve. So there’s a brand new valve in there.

SOPHIE BUSHWICK: And when’s the new launch date?

BRENDAN BYRNE: So the new launch date is Friday, May 17th, at the earliest, is what they’re shooting for. I hope it happens May 17th. I’ve got a vacation planned in late May. So I’d like to see this go before– before I go on vacation, but certainly, they consider astronaut safety more than they consider my vacation plans.

SOPHIE BUSHWICK: Probably, that’s a good priority for them.

BRENDAN BYRNE: A very good priority.

SOPHIE BUSHWICK: And you mentioned that SpaceX has been doing a lot of the work of ferrying supplies back and forth and starting to deliver astronauts as well. So once this capsule gets into the groove, do we have any idea of what the split will be between SpaceX and Boeing ULA for trips to the ISS?

BRENDAN BYRNE: Yeah. It’ll be evenly split. Every six months, they’ll alternate between a SpaceX Dragon capsule and a Boeing Starliner capsule. NASA really wants to have redundancy built into their rides to the International Space Station. If something were to happen to say SpaceX’s Falcon IX rocket, that could possibly ground the crew. So NASA really wants to have these redundant crews going back and forth.

SOPHIE BUSHWICK: Brendan, thank you so much for taking the time to talk with us. I really hope you enjoy the launch when it does happen.

BRENDAN BYRNE: Thank you so much, Sophie. It was fun.

SOPHIE BUSHWICK: That’s Brendan Byrne, Assistant News Director are at Central Florida Public Media.

Copyright © 2024 Science Friday Initiative. All rights reserved. Science Friday transcripts are produced on a tight deadline by 3Play Media. Fidelity to the original aired/published audio or video file might vary, and text might be updated or amended in the future. For the authoritative record of Science Friday’s programming, please visit the original aired/published recording. For terms of use and more information, visit our policies pages at http://www.sciencefriday.com/about/policies/