Originally Posted by
Ian W
The subsystem architectures may not be different but the kind of cross checking that is done between ADIRU and GPS and GPS and Altimeters and so on is far more sophisticated. Not only that but the cross checking software is replicated in different processes sometimes written in different software to the same spec. All these duplexed and triplexed subsystems are designed to watch each other for mismatched outputs and out of specification behavior. This makes it very difficult for a hacker to proceed even in the extremely unlikely event that they manage to access one of these subsystems.
I totally agree with you - which is why I said earlier that in theory it should be easier to hack earlier generation aircraft. As far as we know that has never happened to any significant degree so I feel that the danger from some hacker in Moscow steering a passenger jet into a building is somewhat overblown.