In a Reuters post recently titled 'Researchers chase goal of non-hijackable plane' :
'The researchers aim to create a "last barrier to attacks" on planes in flight.
Among the non-hijackable plane's features: computer systems designed to spot suspicious passenger behavior, and a collision avoidance system that will correct the plane's trajectory to prevent it from being steered into a building or mountain.
The researchers are also investigating the possibility -- although they say it is probably some 15 years away -- of developing an on-board computer that could guide the plane automatically to the nearest airport, in the event of a hijack.'
An auto-pilot park-itself-plane-under-hijack? Now that's 'smart'...