I'd have thought that any new contemporary aircraft could easily be converted to autonomous and/or remote control given sufficiently robust computer systems, that I'm sure will evolve in my timescale. 25 years ago the concept of a personal computer looked a little far fetched, we've come a long way.
Well on the surface a fair point, however, I'm flying 20 year old aircraft now. I've just converted from flying a 40 year old aircraft. Neither had any seriously major changes or upgrades to their systems in that time despite all the possible additions for efficiency and reliablilty. The cost of certifiying the changes would outweight the potential lifetime gain.
Aviation regulators , particularly in Europe, are conservative to the point of ludditism (or however thats spelled).
For instance and I know this is not directly relevent. the C-130 has been in RAF service for 30+ years. yet you could not certify one on the UK commercial registration.
Its all very well for the military to have UAV's but IMHO it will take a very long time before we see any in a public transport role.
ps , of course we could all be taking sub orbital flights to our holiday destinations by then. Go Spaceship One
http://www.scaled.com/projects/tiero...Index/body.htm