Some people have suggested that a system could be installed to allow ATC to control an aircraft remotely in order to take control away from hijackers who might have gained access to the flight deck.
Bad idea. Why? The technology may already exist but installing such a system would create a new vulnerability. If there is a system for remote control of an aircraft then there will be the possibility that non-suicidal terrorists could gain control of that system and use an aircraft as a missile without putting themselves in danger.
[ 15 September 2001: Message edited by: stagger ]