Transcript for Black Box Pings Detected in Search for Missing Flight 370
those promising developments this morning in the search for Malaysian airlines 370. Two separate signals that could be picking from the black boxes have been picked up in resections of the Indian ocean. We want to get right to ABC's David Kerley for all of the latest. Good morning, David. Reporter: Lara, this is really the best lead since this plane disappeared 31 days allege. They were able to narrow the search to the strip of Indian ocean right here you see it and they were Chinese said they heard pings down at the bottom of the screen but end here the Australians and Americans using U.S. Gear heard the signal two different types and searchers think they may have heard both black boxes. On board this Australian vessel, the "Ocean shield" the ping locator heard something two separate times. There's been two contacts thus far and they were early on in the process. Reporter: It was in the middle of the night Saturday into Sunday when crews heard something like this. And saw it on their screens. For 2:20 they heard the signals, they turned back and heard it again for 13 minutes. The two hits about a mile apart. Clearly this is a most promising lead and probably in the search so far it's the -- it's probably the best information that we have had. Reporter: This morning, the ocean shield is crisscrossing a small search area, three square miles of the Indian ocean with depths of nearly 3 miles. And they already think they may have heard both boxes. 9 cockpit voice recorder and flight data recorder. We did hear two signals. There was very similar frequency ranges involved coming from different locations. That's actually pretty encouraging. Because, remember, there are two black boxes involved. Reporter: The searchers would like a third hit allowing them to try angulate where these signal pulses may be coming from then this underwater mapping robot will be sent to the bottom of the ocean where its sonar will look for wreckage. The best lead so far and searchers are struck they may be close without ever even seeing wreckage on the surface. The Normal telltale sign of where to look. I think it's quite, quite extraordinary and while I'd like to see now is us find some wreckage because that will -- that will basically help solve the mystery. Now, this is remarkable, that first ping in the Australians and Americans heard was when they had actually reeled in this listening device and brought it up closer to the surface to prepare for a turn and heard the first ping. The manufacturer of those pingers tells us even though we are past the guaranteed battery life, George, they believe that the searchers have three or four more good solid days of signals to try and really pinmountain if this is the wreckage. Let's hope they're right. More on this from ABC's aviation consultant Steve ganyard. I'm sitting here with one of the black boxes on 9 desk and everyone has said this is the most promising lead yet after so many false ones. It sure is, George. Very, very encouraging. We have would solid hits. If we can get one more they can try angulate a good position but even with these two I think we have a very good chance, maybe not today, maybe to the this month but we'll unravel the mystery of flight 370. And we just heard David say the manufacturer believes there could be several more days left of pinging on this black box. The range anywhere from 30 to 45 days but in part it depends how old it was. And we're down to just days so hopefully in the next couple of days they can get that hit. Even if they don't we have this side-looking sonar that makes a grainy black and white picture from the bottom of the ocean floor. Even if we lose the pingers we're in a small enough search area we'll find wreckage on the bottom. In the air France case even though the pinger had gone out they were able to find wreckage months, years later. That's correct. That's the key. It could be years later but based on what we have in terms of position now it's just a matter of time before we find it. Steve ganyard, thanks very much.
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