the search effort says there's been no major breakthrough to report at this moment. investigators are already planning what their role will be when that changes. investigators in the united states. barbara starr bring you details. >> reporter: as searchers potentially close in on finding malaysia airlines flight 370, u.s. government intelligence, law enforcement, and aviation experts are quietly talking about what comes next and at what point they'll take a bigger role in the investigation. if new pings are found from the plane's black boxes. it could still take weeks to locate the voice record cher investigators hope will tell them what was happening in the cockpit. but it's the data recorder that may tell them the most about how the plane went down. >> it's going to tell you what switches were moved, when they were moved. what your air speed was, what your altitudes were, what your heading was. it's going to give you an entire