I don't think we are ever going to get them, frankly. Or at least not passenger planes. Machines do break down, no matter how many redundant systems you put in. You want to always have someone on board who can help, even if the plane flies by itself 100% of the time during normal operation. Unless of course, that's what you meant. I mean that planes will always have to have someone familiar with flying on board, even if that person is not doing anything most of the time.