No reporter has been closer to the scene than our David Wright. Just off that p8 poseidon sub hunter you see right there. Let's go to David. Reporter: Moments ago, we touched down back here at Perth... See More
No reporter has been closer to the scene than our David Wright. Just off that p8 poseidon sub hunter you see right there. Let's go to David. Reporter: Moments ago, we touched down back here at Perth having tagged along with the U.S. Navy aboard its p8 surveillance plane on a nine-hour mission to the southern search area. This is one of their first missions to the southern search area and while we were on our way, a three-hour journey just to get there, the call came in that we were being diverted to a point that there was a promising lead. Wouldn't be clear about what it was, however, it's since become clear the Australian prime minister came forward and said, a 76 chunk of what was debris spotted is the coordinates we were sent to. Raising everybody's hopes. They even said that there were more planes behind us that were being depatched to the same location to do more searching, however, expectations raised and then disappointed. Once we got there, it became clear that that image is probably a freighter that we spotted in the water there. We saw the bridge of the freighter clearly and was not what we were looking for. There were two other radar contacts that seemed promising while searching that area for three hours, those turned out to be pods of dolphins. So, David, no sign of anything connected to the Malaysian flight? Reporter: No sign that we saw and this is a plane that gets very close to the water. Most of the time we were skimming at about 300 feet above the water. You could see a basketball if it were in the water. Plus, they had high-tech radar sweeping 16 miles on each side of the plane. If there was something there, this plane surely would have spotted it. There were watchers in the windows throughout the time that we were in that search area, however, they're pretty confident the U.S. Navy that in this 4100 square miles at least nothing from the plane is there. On the surface. Wow, David Wright pretty dramatic information right there.
This transcript has been automatically generated and may not be 100% accurate.