Rescue teams race to find missing men in submersible, including Hamish Harding

A MARTÍNEZ, HOST:

The Coast Guard says rescuers heard some kind of underwater noise while trying to find a missing submersible in the North Atlantic. That's the first positive sign so far from the international search for the vessel that set off on Sunday to view the Titanic. Coast Guard Captain Jamie Frederick told reporters the five people aboard may be running low on oxygen.

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JAMIE FREDERICK: It's a unique operation. It's a challenging operation. But right now we're focused on putting everything we can at it and searching as hard as we can and getting the assets out there as quickly as we can.

MARTÍNEZ: Those assets include ships, planes and sonar probes dropped into the sea. Terry Virts has a friend on the Titan. Virts is a retired Air Force colonel and NASA astronaut. Colonel, do you know how your friend Hamish Harding came to be on this submersible?

TERRY VIRTS: Well, Hamish is an explorer by nature. And this just is the kind of thing that he would want to do. And he, I guess, you know, looked for the company that does this. The - and this is basically it. If you want to go to the Titanic, this is probably how you're going to get there. So I think there was not a lot of other options for him.

MARTÍNEZ: Yeah. A couple of days ago, you tweeted, it was good news we haven't heard any catastrophic sounds on sonar. What sounds would have been bad news?

VIRTS: Well, sonar can pick up, you know, a crushing sound or an explosion. And I - you know, I'm not directly involved in the rescue effort, so I can't say exactly what they've seen and exactly what the latest is. But the really good news - and this was just a few hours ago that this was reported - CNN, I think, broke the story. They read some government documents. I'm not sure how that they had been hearing this banging noise apparently every 30 minutes. And that's how the rescue operation is probably going to find the folks, just taking a wrench and banging on the wall. That sound can travel through the ocean. So that was encouraging. They were banging about every 30 minutes. It's not known for sure if it's this crew or if it may be another sub in the area. But that was definitely good, positive news that we haven't heard for several days.

MARTÍNEZ: Yeah. And when you tweeted out what you tweeted out, you said there's still hope. That's how you ended the tweet. Where is your heart on that today, considering that the oxygen and the math on that doesn't feel good?

VIRTS: It's not. It's - you know, they're probably down to their last day, to be honest. The good news is they had a private company - a private energy company was letting us use their ROVs. They were not able to go all the way down to the surface. But today, two French submersibles that can go down to 6,000 meters should - they should have already been on station about right now. So they're going down. Hopefully they can find them. And a U.S. Navy crane should be on station shortly, any minute now. And once they find them, they're going to try and grab them with this crane and pull them up.

So the theory is they're stuck somehow on the bottom. We won't know until we find them. It's a search and rescue. So the first part is search, and the second part is rescue. And there's probably not much more than a day, maybe two of oxygen. So, yeah, it's very tough situation.

MARTÍNEZ: Colonel, you were an astronaut. What do you think of these kinds of trips, this particular deep-sea exploration or going to space, things like - that require years and years of training being available to just normal people?

VIRTS: It's funny. People always ask me, when can normal people go into space? And I laugh like, I guess I'm not a normal person. But a trip like this on the Titanic obviously requires a pretty good paycheck. But the good thing about it is there's scientists that are hired by the companies. They're actually studying the Titanic. It's been changing year over year, studying the sea surface. So there are scientific benefits that come from it. And right now the main - there's going to be lots of post-mortem on the whole accident. But right now we're just trying to find this crew. And that banging news is positive news. So we'll see.

MARTÍNEZ: And don't sell yourself short. You went into space. So you're as close to a superhero as we get. Terry Virts, former commander of the International Space Station, friend of Hamish Harding, a passenger on the Titan. Thank you very much.

VIRTS: Thanks for reporting this story. It's a good story. Please keep it in the news. Transcript provided by NPR, Copyright NPR.