I fly for a living, and I currently work in developmental flight test. One of the programs I am working on is a UAV.

It's going to be a very, very long time before we see autonomous airliners. I'll talk about specific technical hurdles, but I think the biggest issue is psychological: it's one thing to entrust a bunch of freight to an autonomous vehicle, another thing entirely to entrust dozens of living, breathing human beings to such (the article discusses this, including the concept of "shared fate"). I am confident that autonomous airliners will only come into service when autonomous aircraft technology reaches a point where the computers are able to handle every aspect of flight safety better than humans. Right now they can already do some of those things better than humans, and those tasks have already largely been shed by human pilots and entrusted to their computers. I think there will be a gradual transition as the computers are able to take on more and more of the tasks. The article also mentions how this process is already causing basic aviation skills to atrophy in pilots who leave too much to the computers. I think this is a very real problem, and I think it was a major contributor to the Air France flight 447 crash. Prudent pilots do more manual flying than is strictly necessary because that's the only way to maintain proficiency. If this problem becomes severe enough, expect to see the FAA establish more granular proficiency requirements.

The author talks a lot about how much the military is using UAVs, and seems to think that this is a good model for civilian applications. It isn't. The military has an entirely different set of risk considerations than civil aviation. Take the example of medivac UAVs: a medivac UAV will almost certainly have a higher mishap rate than a manned medivac helo, which would be completely unacceptable for civilian purposes. However, for the military that increased mishap risk is more than offset by the risks of putting an entire human crew into harm's way just to medivac a single wounded soldier.

Military UAVs currently in use generally have much higher mishap rates than their manned counterparts, but the military tolerates this because aicrew don't die in UAV mishaps, and UAVs are generally less expensive to replace than manned vehicles. Part of the reason for this is that features designed to prevent or mitigate mishaps cost money, and it is often cheaper to leave many of them out and accept the higher mishap rate, especially when no human crew is involved. However, part of it is that autonomous systems still just aren't as good at flying safely. For the military, the benefits outweigh the costs, but I really can't see a for-profit corporation reachig the same conclusion.

>Northrop Grumman has built some sense-and-avoid savvy into the unmanned helicopters and other UAVs it's developing for the U.S. Navy.

I happen to be intimitely familiar with one such system, and somewhat familiar with another. This sentence is utter BS. I can only assume that the author was fed a line by an NGC PR-type and took it at face value. A more honest way to say it would be:

Northrop Grumman is trying to incorporate limited sense-and-avoid capabilities into the unmanned helicopters and other UAVs it's developing for the U.S. Navy.

Moreover, FAA has a requirement for "see and avoid," not "sense and avoid." The military is trying hard to sell them on the idea that it should be "sense and avoid," of which "see and avoid" would be just a subset, but so far the FAA has remained deeply skeptical. The FAA is right to be conservative about this change: none of the currently proposed systems would be as effective at collision avoidance as the Mark I Eyeball, and thus far the systems I am aware of (to which the quote from the article was referring) are still a very long way from working properly. This seems to me like the kind of technical problem that eventually can be overcome, but it's going to take a lot of work to make that happen.

Because "see and avoid" is so critical to safety of flight, and because UAVs can't currently do it, the FAA does not allow UAVs to operate in its airspace, with some tightly restricted exceptions for military and law enforcement UAVs. I doubt very highly if they would make similar exceptions for civilian purposes, and even if they did, the restrictions involved are so limiting that there aren't many viable applications.