I like the 100 year estimate. Maybe a little sooner but who really knows WHEN.

I think it has already started in the military, and gaining ground at warp speed. Sadly, the days of carrier aviation are numbered. In the next 40-50 years there will be no more people taking off and landing on boats, the $$$ will win out on that. Fighters, bombers, recon will all become automated and/or controled from ship or ground based stations.

Frieght will become the first single piloted and eventually un manned aircraft comercially operated. For pax, it will work down to single pilot with a dispatcher/co pilot working and monitoring the flight(s) from their ground station. This will lead to un manned commercial pax carriers. Remember in the future people will grow to implicably trust computers more and more, and our human error less and less. Our kids kids will grow up totally emersed in a very, VERY techno savy culture and to board an airplane where they see a guy in charge in the front, then all the doors shut and they don't see anyone till they land, they will be ok with that (no too unlike we do today is it?).

Honestly the biggest challenge will be the people searving drinks and snacks in the back that can lead if there is some type of incident......