What The Bluefin-21 Sees Underwater
PEREIRA: Welcome back to NEW DAY. Search crews this morning set once again to launch the Bluefin-21 back into Indian Ocean for a second day of using the submersible side-scanning sonar. They want to map the bottom of the ocean. We know though this is meticulous and slow process. What exactly is the Bluefin seeing down there? Well, a man who knows this very well is David Gallo. He is the co- leader in the search for Air France 447, a director of special projects of Woods Hole Oceanographic Institution. You are the guy to talk to about what the Bluefin is seeing. In fact, you brought some images for us. I want to show you this. People are probably wondering what this image is. Tell us. This is an image taken by Bluefin.</s>DAVID GALLO, CNN ANALYST: Yes. You're looking down. This is made with maybe one pass, maybe a couple of passes. You can see the shape of a ship, the stern, the bow and here we have two ships together.</s>PEREIRA: They had collided. Some sort of investigation.</s>GALLO: I believe this is a case where ships hit each other, sank together. The different colors represent intensities. So maybe something that's shallower or closer to the sonar itself.</s>PEREIRA: Could we expect then that -- and how quickly would we expect that investigators could get something of this detail if the Bluefin spot something down below?</s>GALLO: Right away but they're not looking for something we don't think anyway quite this big as big as a ship. So it would be a smaller, maybe piece or half the size of this.</s>PEREIRA: All right, let's move on to looking at this. I want to show you this because we talked about the sonar side-scanning technology. I think this illustrates it very well.</s>GALLO: It does.</s>PEREIRA: First of all, what are we looking at here?</s>GALLO: You are looking at a pass of the vehicle. The vehicle is going from -- you're looking down. That torpedo shape is move that way sending out beams. Every second, ping, ping, ping. Little by little, line by line, builds up this image. When you see bright like that bright reflection. That means its close. Here's a shadow. You can get a lot of information out of a strip like that.</s>PEREIRA: Again, this strip in the middle is very important to explain. Why is that being shown this way?</s>GALLO: Because it is side scan. The vehicle is sending out that fan of sound to either side and it leaves a gap beneath the vehicle.</s>PEREIRA: So this is the gap that is not recording the data --</s>GALLO: You need to fill that gap up because sometimes what you're looking for may end up inside that gap. Sometimes they overlap the tracks.</s>PEREIRA: Is that also why they have to have it not right on the surface. That it has to be sort of hovering above?</s>GALLO: Yes, that's partly right. The closer you get you can close the gap more, but then you start to lose the edges. You want to find -- decide what am I looking for and make it optimal for that.</s>PEREIRA: So there are ways to account for that gap.</s>GALLO: Yes.</s>PEREIRA: OK, then moving on to this. You were involved in the "Titanic" expedition and this is an image. Tell us what we're looking at. I want to give you an opportunity to draw and show us the detail here.</s>GALLO: Well, we used the Rema 6,000 vehicles. We had two. They are just like the Bluefin.</s>PEREIRA: Same technology.</s>GALLO: They go to 6,000 meters. A little bit deeper than the Bluefin. We had three of them when we found Air France 447. We used two of them here on "Titanic." You can see the seams the vehicles go up and down. It's about a mile or so long and -- or across. Those are the vehicles. The "Titanic" broke in two. This was 102 years ago today that it sank. That's the bow, this is the stern inside here. Separated by about six football fields. This is a debris field. Classic debris field. A lot of rubble. To the trained eye you notice there's something very different here.</s>PEREIRA: How can you tell? The trained eye, how can you differentiate between rock and just sediments settling?</s>GALLO: Well, you see something like this is actually a shadow behind it. Some of the things are shadows. Look at these things. We've talked about this and you noticed those before. Those look like they don't fit the natural background. In fact, pieces of "Titanic."</s>PEREIRA: Just a closer look.</s>GALLO: Closer look at the bow.</s>PEREIRA: Last but not least I want to show this because once the mapping is done they're going to send in a different type of technology.</s>GALLO: Right.</s>PEREIRA: That has a camera attached.</s>GALLO: We go from sound to using light, to using a camera. Best resolution.</s>PEREIRA: This is the picture that was taken of the "Titanic?"</s>GALLO: This was done with the Remora, which was operated by Phoenix and we can expect that down the road I think to be involved in something like recovering the black boxes. They've recovered the black boxes from Air France 447 with this vehicle.</s>PEREIRA: Is that data immediately sent? Is it a series of digital images?</s>GALLO: It's a long process because you see each one of these is one frame and there's maybe 100 frames inside there. That's the whole bow of "Titanic" where the bow broke in half. The tip where king of the world, way up inside there, the mass, the grand staircase. It takes a lot of processing to be able to put together a mosaic like this.</s>PEREIRA: Really? David Gallo, thanks so much. Appreciate it, real pleasure -- Chris.</s>CUOMO: All right, coming up on NEW DAY, Rebecca Gregory and Pete Demortino, both injured in the Boston attack, but today they are proof that love conquers all. The newlyweds will join us live.