you go to an atm, you e-mail and text. that may indicate something about intent. delook at and then delete a file, for example, and then you look at the other digital clues and say, we'll never have access to this human being but do we begin to understand what is going on in his mind? this is about understanding and intent and whether he was flying on the flight simulator that tells us what was in his mind. >> when you hear what the current fbi agents are looking for in the flight simulator, what does that tell you about their investigation, where they are, what they are looking for? >> it tells me that we're at an early stage. there are two characteristics that we're looking at here. one is, what happened to the plane? electronic? mechanical? the second is what happened inside somebody's brain. we have no access to either the crime scene or the criminal, potentially. to understand the number of