Quote Originally Posted by TruBlue View Post
Apart from industry experts admitting it was possible and a mother recognising her sons voice. Additionally Airfones were available a long time prior to 9/11, have you never seen Die Hard 2.
They now work on transatlantic flights. United 93 wasn't mid Atlantic at the time of the crash, and whilst neither I nor splotty know how high it was flying, it is possible it was flying low enough to be in range of a cell tower and possibly connected via the aircraft comms system.