Originally Posted by ZENSMACK89
"Spilt-second" is quite an exaggeration. I also don't know what he means by "flipping it over" - it's not a TV remote. There is no "hijack" channel that can be selected by the push of a button.
There are four knobs, two outer knobs and two inner knobs, and in most cases all four knobs would have to be adjusted to broadcast the hijack code. Let's say the transponder was set at 2454. The left outer knob would have to rotated counter-clockwise for 3 "clicks"; the left inner, clockwise 3 clicks; the right outer clockwise 3 clicks; and the right inner counter-clockwise(or clockwise) 4 clicks....
(767 ATC/Transponder panel photo for reference)
If you think that can be done in a "split second" without any errors or fumbling around, when there are knife wielding maniacs hell bent on slitting your throat, well I don't know what else there is to say. Also, you should understand that setting the ATC panel to 7700 wouldn't exactly be the highest thing on the pilot's priority list in the event of a violent takeover attempt.