[SR2Z]

I'm not actually sure how hard landing is. Most airports that support autonomous landings do it by having ILS antennae that guide the airplane to within tens of feet of the runway, at which point the airplane switches to radar for altitude.

Automatic landings started in 1964. I think that it seems hard mostly because of how tightly regulated aviation is - modern technology could probably make things a lot better if people were more receptive to the idea of heavy automated aircraft over populated areas.

[adgjlsfhk1]

landing is easy. the hard part is landing with 20mph cross winds and one engine out (or other mechanical failures). we've had auto-land that is 99% reliable for a while now, but you need to get to 6 9s before you have a system safe enough to replace pilots

[SR2Z]

I think that as long as the autopilot is able to fly in a crosswind or with an engine failure, it can probably land with one. Autopilots are already able to do these things.

I doubt anyone has tested this in depth, but I'm not sure there are too many configurations of airplane these days where a human can safely land it and a computer can't. Maybe if a big chunk of wing or control surfaces were totally gone, but even a human pilot isn't getting 99% reliability in a situation like that.

In any case, I don't think that the first candidates for automation are gonna be passenger flights. It will probably be small cargo planes first - Cessna Caravans and other turboprop aircraft where the cost of paying pilots is roughly similar to the price of fuel.