Originally Posted by
Gauges and Dials
To pick one simple example: If the selected track and altitude were 045 and FL390, and *all* of the displays were all showing data consistent with that, including updated GPS positions, etc. but the airplane was actually tracking 065 at FL300, how quickly do you think a crew would notice? My bet is on "never".
Ok, so lets go with this scenario. For example, spoofing GPS is clearly possible since even Wikipedia lists several suspected and/or confirmed events. But the airplane has an IRU, and that I'm almost 100% certain is hack-proof! What happens if that and GPS deviates? I'm not even a pilot so I have no idea. The idea that someone could hack _all_ the instruments required to spoof altitude and position to the pilots, _from the ground_, still sounds insane to me.
As a service technician though with access to the hardware, that would be a completely different scenario. Is that whats meant by "from the ground" =)