going on. >> keith mas billion dack, if only the final two hours are that which is recorded and if in fact this plane was flying on its own devices for several hours, those tapes could be blank? >> absolutely. welcome to intelligence work, law enforcement work, welcome to crash investigation, michael. it is piecing together a puzzle and every new piece of information has to be dealt with in the context of what you already have and what your assumptions are. >> there's such frustration, i feel for those families. but here in the states, around water coolers, everybody says, my god, with the technology we have today, why isn't there a solution to this? why after air france 447 have we put ourselves in a position like this? >> we had all the error messages going back to air france. we knew in realtime what was occurring, what's amazing is that the acars messages stopped