For those who would say aeroplanes would be better off flying by computer (and I am sure there is none here), I would urge you to read the writings of Professor David Parnas.
Dr. Parnas was the man who finally convinced Ronald Reagan to drop his 'Star Wars' idea because, and I quote: "it would be impossible to write an application of sufficient quality that it could be trusted to prevent a nuclear attack"
The same situation is true in an aeroplane. It is not the computers that we need to worry about, for they are triplicated (save the possibility of a Byzantine failure) but the ability of our programmers and software engineers to accurately envisage and write software to handle all possible failures.
So what we need is a group of pilots with 20,000 hours of experience that want to go through six years of University education to become software engineers. Then we might be 99% sure of catching all the possible combinations of holes in the Swiss cheese.