I have posted on the subject of taking the man out of the can in the space program (see http://sigma5.blogspot.com/2010/11/space-shuttle-rip.html and http://sigma5.blogspot.com/2010/12/space-final-frontier.html). This post is about taking the man out of the can when it comes to combat aircraft.
I think a lot of people would think that one of the last places where a person could be replaced by a computer would be with respect to airplane pilots. But we have been moving in that direction for a long time. The story goes that when Boeing was developing the B-17 bomber before World War II there was a crash. The crash was attributed to pilot error. Now the pilots in this case were Boeing's most experienced and skilled test pilots. So how did they go wrong? Boeing engineers decided that the plane was just two complicated to fly if you had to remember everything. So the engineers developed a series of checklists. There was a preflight checklist, a takeoff checklist, and several others. With the memory aid of the checklists pilots stopped skipping critical steps and the B-17 eventually became one of the most successful airplanes of the WW II era. And this experience quickly spread throughout the airplane industry. It is now standard for pilots to use checklists as an aide to most aspects of flying.
We now move forward to the middle of WW II. The Germans developed two "terror" weapons during the war: the V-1 and the V-2. I have talked about the V-2 rocket elsewhere and its critical place in the history of modern rocketry. Here I want to focus on the V-1. The V-1 was a robotic jet plane. V-1's were launched from northern Europe and used to attack England. They flew in a predetermined direction until they ran out of fuel. Then they crashed and exploded. That was as sophisticated as the technology of the day permitted. And I doubt anyone would like to be aboard as a passenger. But, in fact, the V-1 was the first robot plane, and a jet plane to boot.
After the V-1s the whole notion of a robot plane was abandoned for many years. It looked like a robot plane was just not capable enough to compete with a human controlled one. But time and computer technology marched on. And while handing complete control over to a robot seemed like a bad idea, handing partial control looked like a better and better idea as time passed. The robot was usually referred to as an autopilot. Originally, autopilots were just capable of maintaining speed, direction, and altitude. This was good enough to make them useful. Long flights involve substantial periods of just flying in the same direction at the same speed and altitude. So the autopilot allowed pilots to (on large commercial planes) stretch their legs and get something to eat. Even in cramped military planes the pilot could disconnect and relax for a while.
But while no one was looking autopilots kept getting more sophisticated. After a while you could plug in a flight plan and the autopilot would change course, speed, and altitude automatically as it flew various legs of the flight plan. And aeronautical engineers continued to study what was involved in more complicated evolutions like take off and landing. For instance, there are a number of airports that have serious weather problems that result in terrible visibility problems. Various systems were evolved where the plane was controlled from the ground. The ground based people had access to radar which allowed them to know where the plane was at all times so eventually they could guide the plane to a safe landing even in "0 visibility" conditions. It turns out that takeoff and landing are more complicated than straight level flight but they can be understood enough so that the process could be reduced to computer code.
While this was going on another trend was taking place, particularly with high performance military jets. They were getting more powerful. "G" is a measure of acceleration. 1 G is that amount of acceleration we experience standing still on earth at sea level. 2 Gs represent twice that acceleration, and so on. It turns out that the human body can operate reasonably effectively while being subjected to several Gs. But there is a limit. Depending on the situation, how long the high G forces last, for instance, this limit varies. But it is somewhere between 5 and 10. As the capabilities of high performance military aircraft have improved, they have become more and more capable of inflicting high G forces on the pilots. This is particularly easy to do in tight turns. If the G force tolerance of the pilot is exceeded the pilot "blacks out" or looses consciousness. An unconscious pilot is an ineffective pilot. Modern high performance aircraft designs spend a lot of effort dealing with this issue. Tremendous effort is put into doing everything that can be done to increase the pilot's G tolerance. This has become a limiting factor on the top performance of the aircraft. The plane can be built to dish out and take more G punishment than the pilot can.
Remember that one of the ways we can subject pilots to too much G is in tight turns. This is critical in dogfight situations. This problem goes all the way back to WW I. The most famous fighter pilot of WW I was The Red Barron. He flew a Fokker Triplane. Why is this important? Because the "tri" in the name indicates that his plane had three main wings stacked one on top of the other. The benefit of doing this was that the plane had short wings. The benefit of this was that he could turn more sharply than a pilot in a plane with one or two longer main wings. That meant he could "cut the chord" (turn more sharply and get inside of the other pilot). This allowed him to get into position so that he could shoot his opponent down without exposing himself, which he did. Turning radius is critical in a dogfight.
This G issue is only one issue where the fact that you have to keep the pilot alive and functional limits the performance of a plane. Jet planes are very fast and very powerful. The Red Barron when flying his plane was primarily concerned with what was happening right now. His plane was highly maneuverable but slow. He spent little of his time worrying about what was going to be happening 20, 30, 40 seconds in the future. That would mostly depend on what he did then and not much on what he was doing now. Jets changed all that. A Jet pilot has to be thinking about the future because what he does now will have a strong influence on what the plane will be doing 20, 30, 40 seconds from now. You have to imagine what the plane will be doing in the future in order to take the right course of action now. This is very confusing and hard to do. Flying a high performance airplane at the limit of its capability is very hard to do.
In the last 10 years we have seen a tremendous increase in the use of UAVs (Unmanned Aerial Vehicles) by the military. Their mission, like that of airplanes in the early days of WW I, was initially focused on gathering intelligence. But, again like WW I, their role quickly transitioned to offensive warfare. We now regularly see stories in the news about "Predator Drone Strikes", events where a UAV was used to blow something up, not just take pictures of it. But, for the most part these UAVs were not robot piloted. They were remote piloted. A skillful person would be at the controls. It's just that he was not in the vehicle. He was connected to it by radio and was piloting it remotely.
But there has also been an evolution in the role of the remote pilot. Initially he had detailed control of the vehicle, a pilot in all but physical location. But this is hard to do. There are delays. Your vision is very limited. Since you are not in the vehicle there is no "seat of the pants" feedback. This made these vehicles very hard to operate. At the same time the power of the computers involved grew by leaps and bounds. And various "autopilot" and "ground control assist" projects had increased the level of detail and sophistication of what could be done to "assist" a pilot in flying. The industry became more and more confident they knew how to get a computer to fly an airplane.
And it is important to remember that these airplanes have no people on board. So if the computer makes a mistake and the plane crashes no lives are lost. This made it possible to push the envelope. Now more and more of the detailed flying of these UAVs is being done by a computer. The operator, no longer engaged in the detailed piloting of the UAV, concentrates on where the vehicle should go, what it should focus its camera on, etc. This means that the level of skill and the amount of concentration required of the remote operator is much reduced. This is very important because, according to the story, the U.S. now has more than 7,000 UAVs in its inventory. And many of these UAVs are specifically designed to be operated by front line troops who do not have a high level of training and skill in piloting and who may be being distracted by bad guys shooting at them.
The story was about three new UAVs. One of them was called a "Global Observer". Its top speed is 120 MPH. But it can fly as high as 65,000 feet and stay in the air for 5-7 days. This puts it in line with current UAVs. Its capabilities are greater but they generally fall into the "more of the same" category. It is the other two UAVs that are the interesting ones.
The X-47B and the Phantom Ray look like fighters. The X-47B is capable of a top speed of over 500MPH and the Phantom Ray can go more than 600MPH. These are "fighter plane" specs. They are also fighter sized and both look a lot like F-117 stealth fighters. Their specs (ceiling, range, payload weight) are also similar to the F-117. They are definitely NOT designed to be "loiter leisurely on target for long periods of time to do reconnaissance" planes. They look like first generation robot jet fighters to me.
And there is no practical reason not to go in this direction. Most dogfight maneuvers were developed during WW I so the "art" is well understood. A lot of dogfight tactics depend on geometrical considerations, who is above who, who is going faster, who is going in what direction, the relative positions of the craft, that sort of thing. Computers are good at figuring out this sort of thing and keeping it straight. The other thing fighters are used for is "stand off - fire and forget" tactics. It is even easier to reduce this kind of situation to a set of rules that a computer can understand. And, if you throw in a random number generator, computers can behave in an unpredictable manner.
Computers are now capable of making billions of computations per second. And they are small enough and cheap enough that you can easily put several of them on board, if one is not enough. They can easily be made rugged enough to remove the performance limits now imposed to keep the on board pilot alive and functioning. It may even be possible to reduce the size of the plane and increase either the performance or the payload of the UAV compared to a manned fighter. This is done by eliminating the pilot and all the support infrastructure necessary to keep him alive and functioning. All other things being equal, the higher performance plane has a big advantage.
There are two issues that can slow things down. The more minor issues is communications. Current UAVs are in something like continuous communication with ground support. It is possible that the bad guys could disrupt this communication or it might be important for the plane to go "emissions dark". This means that the plane is on its own with no "flexible" pilot on board. And in some circumstances this may be a problem. But it is also sometimes a problem that the human pilot loses focus, gets distracted, forgets something, or otherwise screws up and blows the mission. So this is a trade off that will eventually, if it doesn't currently, tilt toward the UAV.
The bigger problem is that a lot of this is run out of the Air Force. The Air Force is run by pilots and ex-pilots. These people have every interest in keeping the man in the can. They will deploy their substantial, perhaps overwhelming, political clout to make sure that the man is never taken out of the can. We can already see this in effect. In spite of the fact that both of these planes look like robot controlled fighters to me, the official list of their missions does not include active combat. Instead they will be used for "surveillance", "reconnaissance" and perhaps "electronic attack" (e.g. supporting the real warriors in the manned vehicles). Although, those sneaky Phantom Ray guys did sneak "ground strike" in. But that's probably just looking after those ground pounder infantry pukes, something the Air Force has always avoided as much as possible.
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