Transcript for Missing Malaysian Plane: Chinese Ship Detects 'Signal Pulse'
We begin with those reports from the Chinese that they have detected sounds underwater one month after that plane vanished. Let's get to the map we have grown familiar with. The possible flight path of the plane and that area right there is where the signal was picked up. This is the ship. Part of the international fleet out on the water. We do a team coverage. There are a lot of questions whether this is the real thing or they heard something else. Clayton Sandell in Australia tonight. Clayton, good evening. Reporter: That's right there is a big new development tonight. But investigators are scrambled to figure out this is just another false alarm. Nearly one month after the jet carrying 239 people vanished. China's state media today claims this Chinese ship detected that signal pulse heard on the same frequency used by emergency beacons like the once attached to the black box recorders. Australia in charge of the search says what the Chinese say they heard is consistent but stressed they cannot verify any connection. To the missing aircraft. A Chinese plane reported seeing debris near where the pulse was heard. But so far, weeks of searching the Indian ocean has failed to turn up evidence. The search becoming more urgent because the pings may be just days away from going silent. Their batteries running out. I think the warrantee runs out probably on Sunday. We may get five days after that. If they're good batteries, you might get a week or so longer. We're getting close. Reporter: Today two ships launched underwater sensors. But the devices need to be within one mile to hear them. And the search area the enormous. 83,000 square miles. The size of the state of Kansas. So much territory. So few clues. But Malaysian authorities say they are not giving up. We will continue to search with the same level of vig -- vigor and intensity. Reporter: They are considering sending more teams to the area. Where the pings were heard. They are desperate to find out whether they are from Malaysia 370 or not. I want to bring in John Vance, a pilot himself. We need to learn much more about what exactly what was heard. When you learned this Chinese ship detected a pulse signal not far from the search area what did you make of it? What got my attention, the frequency they thought they picked up which is exactly the same frequency 37.5 kilohertz. As what is on these two boxes. If that is sustained, if they heard that on a continuous basis, they may have something. But you told me there are many things underwater sounds that can be detected. Absolutely. The ocean is a noisy place. One of the reasons they picked that frequency is because fish and whales don't normally communicate on that wavelength. But a nuclear submarine might emit a signal. The proof is getting over that site and hearing those signals. As we heard Clayton report, it was four week ago this weekend when the jet disappeared. The batteries have got to be nearing their end? They're getting close. The guarantee is 30 days. But it will go 45 days if the batteries were fresh when the jet took off. That gives us a bit more time but not much. Even that disk itself keeps the information intact. Probably for centuries. John, thank you. We turn next to an incredible
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