last communication between the co-pilot and air traffic control. what does that tell you? >> well it's quite interesting if it's reliable evidence. it's not been clear to me who's seen what of that acars communication system. so i'm not sure where that went, so, we've had a lot of evidence of marginal value. but if clearly that was -- if that's established as solid evidence, that this turn was programmed 12 minutes in advance of when they lost communication, okay, that would clearly point to, as many other things have pointed to, some deliberate act either by the pilot or an intruder. >> because you would tell air traffic control, presumably, that you had reprogrammed your flight path, if it was no nefarious reason, correct? >> absolutely. i mean, that's one of very many things. as soon as you turn off a transponder, if i'm flying an