Transcript for Another Signal Detected as Time Runs Short in Flight 370 Search
Now, to the latest on the search for flight 370 and the new underwater signal detected this morning. ABC's David Kerley has the very latest from Washington right now. David, good morning. Reporter: Good morning, Amy. This latest signal was picked up by an aircraft. They're not sure if it was from the black box, which would help narrow the search. And this morning, we're going to take you to the bottom of the Indian ocean, to the area where they are looking. It's not flat. There are ridges and valleys here. You can see how deep some of these are. But the area they're looking at is right up here, on the northern edge of this plateau. This morning, listen to some of "The ocean shield's" actual recordings of the four ping detections. Experts say that is a manmade signal and consistent with a black box recorder. Officials say one of these plans, which have been dropping listening buoys in the area, picked up a signal. But they're not sure if it, too, is manmade. With 16 miles between two of the detections, each ping will narrow the area they will have to map. They've taken an area that was somewhat the size of Pennsylvania, and got it down to a county size. Reporter: But that is still a large area for this robot, the bluefin-21, to map the ocean bottom. As this map shows, the area they're looking at is not flat. Nearly 15,000 feet below the surface. Officials have decided to race against the life of those batteries, hoping for a few more transmissions from the pingers, narrowing the search. The bluefin, which travels very slowly as it uses its sonar to map the bottom, hasn't even been in the water yet. Just takes time. The smaller the area, the better. It reduces the time you have to search back and forth. Reporter: But having an indication of where the jetliner may be on the bottom, has allowed searchers to look at the ocean currents. And they're sending planes miles to the northwest of the underwater search, hoping they can find some debris on the surface of this vast ocean. So, this morning, the Australians are listening to what that plane heard a bit ago. If it is the black box, it's one more piece of data that will help pinpoint the wreckage. George, I should mention, they're bringing a british ship back up here to where "The ocean shield" is working. It was down south. And they'll have two listening ships within the area within a day or so. David, thanks very much. Now, to the bizarre kidnap and rescue story. A military contractor with high security clearance, abducted
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