for hours in some sort of controlled flight. you know, we talked to one very experienced triple 7 pilot that said there are a lot of catastrophic accidents, but planes don't typically fallout of the sky. even industry people are sort of looking at this notion it has to be said, brooke, there is no evidence, no evidence at this point as far as anybody knows that ties the pilot or co-pilot to this. there is no stated motive. none of that. this is certainly an idea that we are increasingly hearing people are investigating, considering, and looking at. brooke? >> we talk about theories, coalescing in the cockpit, could be key to get the files and hard drives with the fbi in a couple of days. barbara starr, thank you so much. >> sure. >> and some of the most critical information may actually come from the pings the plane sent after it dropped out of radar. we know that there was this partial ping, this is what we're talking about today, a partial ping that the plane sent out. that was its last communication.