now investigators have to focus in on him, his background, his capabilities, his systems knowledge of the airplane because whoever was flying this airplane and disabled at least the acars system had to have a high level of knowledge, not just your normal pilot systems knowledge. >> greg i want to be sure that i understand exactly what you're saying because investigators are still looking at passengers on board and the crew, but you seem to be really honing in on the pilots and suggesting it really might be one of the two of them. is that what you're saying? >> i am. because if you start looking at the timeline, it will be a very compressed timeline. if somebody were to try to access the cockpit, they would have had to do it in a sufficient period of time, well before that last radio call. we know that the acars system sent out a last signal and then didn't send anything else out. that was 12 to 14 minutes before