The Sully Scenario
A lot has been made of this. Let's look at it from the point of view of a computer program. It would go roughly like this:
a. Can I maintain altitude? No: branch to landing routine.
b. Landing routine: which airports of sufficient size can I reach? None: branch to Forced landing routine.
c. Forced Landing routine: Of the places I can reach, which poses the least hazard? List, evaluate, sort.
d. Choose least hazardous area.
Now none of this is impossible to program with today's technology. That's not a criticism of Sully: his cool evaluation of alternatives and calm actions were outstanding.
But it is entirely possible to build computer programs that would perform no worse.