This actually says alot about the efficency and skill of the air traffic controllers in this country.
Using an obsolete system with some components using 1950s vintage computers with vacuum tubes. If we had a state of the art system, the computers would have notified controllers that the aircraft had deviated from their flight plans as soon as hijackers took control and maneuvered them.
No sh!t? Wow, that's one to make you stop and think.
So how do they get notified now- or pre 9/11- how would they know when a plane was hijacked? I mean regarding this old system. (Obviously if the hijackers call and start making demands, they know right away) But in a situation like 9/11 where the hijackers aren't interested in letting the FAA know that they have commandeered the airliner, how long would it have taken the FAA to figure it out?
I agree with the other poster, if this stuff is that old- wow, that's quite a task they accomplished that day.