you've got pingers that may expire.is is our best guess now. >> their best guess is a remote area more than twice the size of california. >> good morning. these are all the aircraft flying today. >> the australians take over the search. and soon after the australian ship "ocean shield" lowers its towed pinger locator into the water, pings are detected. >> clearly this is a most promising lead. >> it was, wow, again. >> it was miraculous. they had just put the towed pinger locator in the water. >> i was convinced, this is it, they've got the answer. it's a matter of days. >> the robotic submarine scours the 329-square-mile area where the pings were heard. it's painstakingly slow work. then, two months later -- >> a massive setback in the search for malaysia airlines flight 370. the u.s. navy says the underwater pings are not from the plane's black boxes. >> how big a setback was that? >> oh, it was terrible. it felt like we were right back at the beginning again. >> back to the beginning. and no closer to solving the mys

those pinger locaters, et cetera. are they using anything more sophisticated now?, bpoppy, that was a different type of thing altogether to try to listen to and go to the sound of a pinger. this is actually making pings, yourself, with side scan sonar devices, underwater searching devices towed beneath the ship. they'll make an image of the bottom. they're going to be basically mowing the lawn for up to a year's time back and forth across the sea floor trying to pick up that aircraft. >> you were one of the first scientists to really explore the depths of the ocean and the surfaces and to help map this. what are the major obstacles? because you mentioned bumping into mountains on the ocean floor. i don't think people always think that it really is incredibly rough terrain down there. >> yeah, i think that was interesting to see how surprised people were that there were the greatest mountain range on earth is beneath the sea, the greatest valley is beneath the sea. underwater rivers, lakes, water falls, volcanos, earthquakes, landslides. all that stuff is fairly rou

remember so much focus was on the pinger. so that couldn't have spoebl be the plane. now without the benefit of that it is literally going be -- the ships will be taking the towed sonar device back and forth across the area. they have calculated several possible routs that it could be on. >> and the families are saying they're still not getting enough information? what kind of conversation should they be getting that they're not getting? >> well, i think what would go along a way and i talk with many family members. it's amazing what they're not getting. they are getting their news from the television and contrast that with other currencies where families of air crash victims or lost plane victims are given regularly scheduled briefings by their agencies. by the ntsb or the aaib in other countries. so it would be important at least to give them briefings as to what is going on but right now they're relying on the media. >> all right. seven months later. is it your thinking that you would have hoped there would be some kind of information? >> yes. and if not any indica