The deciding factor here is what kind of plane are we talking about? I think many people could get a small single engine plane down without killing themselves. The success rate would be even higher if they could get someone on the radio to help explain things to them. An airliner on the other hand is a different story, then I think that only someone who already knows how to fly, has at least their private, would be able to get it down. They would also have to have someone on the radio that knew the sytems of the plane helping them.