Transcript for No New 'Pings' in Search for Flight 370
Now, to the ships out searching for missing Malaysian airline flight 370. Trying to hear the pings from the black boxes. And standing by to drop a submersible the second they hear them. ABC's David Kerley is here with the very latest. Good morning, David. Reporter: Good morning, Lara. No new ping detected. But searchers think they have the most promising lead and they're in the right place. This upper yellow . They've broken it down to a three mile-by three mile grid. And it's being swept in a ladder grid. They're hoping for one more signal from what they believe are the black boxes. This batwing listening device is being towed thousands of people below the surface this morning, listening for those every second clicks. But after two long, suspected connections over the weekend, no new pings have been heard. There's been no further contacts with any transmission. Reporter: The batteries on those pinger, now probably fading. Malaysian officials, like the rest of the world, are waiting for a breakthrough. Nothing new, I'm afraid. Reporter: A third hit will help pinpoint where to look for wreckage. Then, this sonar robot will map the bottom, looking for pieces of a plane. All of this could take days or weeks or longer. And then, a submersible like this. The remora, will be brought in. Its mechanical arms, allowing it to dig through debris. It will actually comb through the debris field, looking for the black boxes and any other items that the investigators need to help identify what the cause of the crash. Reporter: It is very deep water, nearly three miles. Equal to 12 empire state buildings, stacked on top of one another. This morning, the best lead is still where the ocean shield is working. Without wreckage, we can't confirm that this the where the aircraft is because we haven't been able to hold the transmissions constantly. So, there's still a little bit of doubt there. Reporter: A little bit of doubt. But they continue to say this grid search, hoping to hear a transmission, if the batteries have not already died. It will take some time to search the bottom. But searchers believe they're in the right place, on the right trail. And they continue to work. Lara and George? Got to hold on to hope. It's so hard to absorb how deep that ocean is. 12 empire state buildings lined up. Thank you very much, David.
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