I do think Civil aviation will go 'airborne' pilotless in time, meaning a pilot will monitor on the ground, however one pilot may (and I'm only thinking aloud here!) monitor more than one aircraft, afterall he/she only has to be alerted to something abnormal to go and deal with that aircraft.
The Military have always been the forward thinking/looking and have the budget to push the boundaries but from their innovations things filter down into civil aviation and even into every day life. Look at HUD's they were a thing of the military aircraft, however we now have commercial airliners with civilian pilots using HUD's in their normal working life.
I think CC you mentioned on here something about timescales 5-10 years I believe. I think that time frame is in my opinion totally wrong, it will be a lot longer than that.
My estimate would be that the military will keep developing their pilotless aircraft and systems, this will lead to civilian users such as fisheries patrol, highway patrols (America use them already) using larger unmanned drones over the next 10 years. Next will come the technology to apply it to cargo aircraft 20 years time. After this has proved to work it will then be applied to civilian air transport 30 - 40 years time.
I suggest it will take this long for a few reasons.
1. Although technology is moving very fast, there is still a huge amount to develop and invent for application to a civil air transport & make it totally safe)
2. Mostly though there needs to be mindset change! that will be the biggest hurdle and it will not happen with the current generation of adults, nor the next however those who are born in 10 years time and approaching their 20's in 30 years time will have been brought up in an environment where pilotless aircraft were a fact of life from the moment they were born and it will be accepted.
Look at London's DLR (driverless trains), when they first announced this concept there was uproar and people categorically saying it would fail and no one would get on a driver less train. Millions use it daily now without batting an eyelid! and before you all jump down my throat, yes I know a train is on rails and cannot fall down but it's about the concept and how peoples attitudes and mindsets change.
I am a pilot and I know that aircraft performing auto-lands do it far better than any pilot and they can do it over and over again without fault, however I currently would still not get onto a passenger airliner tomorrow if there were no pilots up front, even though I know the autopilot can fly it better than the humans but that's because I've grown up with that attitude and having no pilots up front is relatively new to me, but for those born in 10 - 20 years time it will be common place, maybe still in the military or civilian surveillance roles but the change in attitude will have already begun.
3. Legislation would have to change quite drastically
I am not suggesting that every passenger aircraft in the world will suddenly go pilotless, the majority won't but many will.
Someone said something about cost of pilots here, well I would suggest it is a huge incentive for an airline to go pilotless in terms of cost reductions.
Airlines operate with between 4 - 5 full crews per hull (1 crew being 2 pilots), so if an airline has 200 aircraft, it needs 200 x 5 = 1000 crews which equals 2000 pilots to operate it's fleet of aircraft.
Lets say the average salary between the two pilots up front is £100K (it will be more than that). £100K x 5= £500K per hull per year x by 200 hulls = £10 Million (hope my maths is correct!)
£10 million is not an insignificant amount for any company! now of course some of that will still be required to have 'ground' based pilots who would monitor aircraft in the air.
Anyway, I've rambled for far too long, it's a very interesting time in aviation and the debate about pilotless aircraft a fascinating topic. I firmly believe it will happen to passenger airlines but not in my lifetime and I reckon I still have some 30 years left in me (subject to being hit by a bus tomorrow
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