This interview discusses the details of the test which was performed prior to September 11, 2001, the violations of FAA regulations and the possibilities using such technology.
Whistleblower Reveals "Backdoor" 757 Remote Control And Flight Crew "Lockout" Technology Available Prior To 9/11.
The major suggestion is this, "Pilot, you are not in total control of your aircraft, at all times," not even if you start ripping circuit breakers out of the jammed autopilot. Now, you know WHY we've never heard the BLACK BOX recordings of those flights that were used on 9-11, you'd have heard chatter between the flight crew along the lines of, "Full yoke rotation, front back left right and the autopilot's still on. I've pulled everything out of this plane and it's still REMOTE CONTROLLED from somewhere - and the tower still isn't responding to my pleas. What the fuck's going on???"
this page (detail below) was removed from Boeing's website on Feb 03 2002:
FLIGHT DECK: A fully integrated flight management computer system (FMCS) provides for automatic guidance and control of the 757-200 from immediately after takeoff to final approach and landing. Linking together digital processors controlling navigation, guidance and engine thrust, the flight management system ensures that the aircraft flies the most efficient route and flight profile for reduced fuel consumption, flight time and crew workload. [source WAY BACK MACHINE]
this page (detail below) talks about the HOME RUN system, in the 1970's
In the mid-seventies America faced a new and escalating crisis, with US commercial jets being hijacked for geopolitical purposes. Determined to gain the upper hand in this new form of aerial warfare, two American multinationals collaborated with the Defense Advanced Projects Agency (DARPA) on a project designed to facilitate the remote recovery of hijacked American aircraft. Brilliant both in concept and operation, “Home Run” [not its real code name] allowed specialist ground controllers to listen in to cockpit conversations on the target aircraft, then take absolute control of its computerized flight control system by remote means. [source JOE VIALLS]