Tech Industry

Are laser weapons ready for duty?

newsmaker Los Alamos honcho Doug Beason says directed energy beams will soon be able to zap missiles in flight.

The next generation of weapons in the U.S. arsenal could be straight out of science fiction: laser beams and heat rays. And they could be ready for action before you know it.

By the end of this year, the Air Force plans to conduct a first, fully loaded , a jumbo jet packed with gear designed to shoot down enemy missiles half a world away, at the speed of light. The ABL also packs a megawatt-class punch--it's not exactly your garden-variety laser pointer.

For ground troops and embassy guards, meanwhile, a is being put through its paces. The ADS would provide a nonlethal form of crowd control, using millimeter waves (a cousin of microwaves) to cause an intense--but noninjurious--burning sensation meant to encourage people to flee.

That's the plan for these ambitious directed-energy weapons, but for the moment they're still largely R&D works in progress.

One person who's been championing these efforts is Doug Beason, associate director for threat reduction at the Los Alamos National Laboratory and author of the 2005 book "The E-Bomb: How America's New Directed Energy Weapons Will Change the Way Future Wars Will Be Fought." Beason, a retired Air Force colonel who's also served as a science staffer at the White House, recently spoke with CNET about getting a laser to shoot through the atmosphere and about down-to-earth weapons that give a high-tech hotfoot.

In all practicality, the only difference between the laser pointer and the Airborne Laser is just (that) the Airborne Lasers are a billion times more powerful.

Q: What are the everyday uses of directed energy; what are people familiar with?
Beason: Directed energy really is just light that is part of the electromagnetic spectrum. It could be in the form of visible light, infrared light; it could be in microwaves; it could even be in radio waves, but there are two things that distinguish directed energy. First is that the light is coherent--the light all travels in the same direction--and the second thing is that the light is all in phase; imagine soldiers all marching to the same beat. We see directed energy in everyday uses. We see it in CD players--there are very tiny lasers, the diode lasers, in CD players--we see it in DVD players; we see it in the electronic or the infrared remotes that you have with your TV set. There are some stoplights now that use diode lasers. Fiber lasers are used for telecommunications.

Q: Is it simply a matter of scale, the difference between, say, a laser pointer and an Airborne Laser--just a much larger laser--or is there something else that goes on with that?
Beason: There are a couple of differences, but the scale is the biggest difference. A laser pointer typically has an energy of about 5 milliwatts, which is five one-thousandths of a watt, and Airborne Laser has a power on the order of megawatts, that is millions of watts, so it's a factor of about a billion times. There is another difference in that the laser pointer that you use consists of visible light, and the Airborne Laser uses infrared light. The only other differences come in how you handle that type of light--for example, you yourself can keep a laser pointer beam stable by pointing it just with your arm and kind of eyeballing where you want to keep the beam, but for the Airborne Laser, because you're broadcasting this beam over up to many hundreds of kilometers, you have to have a way to stabilize that beam. But in all practicality, the only difference between the laser pointer and the Airborne Laser is just the Airborne Lasers are a billion times more powerful.

And so the Airborne Laser is going through a new phase of testing--there's still ground testing going on now, and there's a plan for a flight test by the end of the year?
Beason: The Airborne Laser has actually flown, but without the laser inside of it. Now the laser has been put inside of it, and the laser has actually lased, that is, it achieved what they call "first light" last year. So it is undergoing testing now, and the first flight probably, if it doesn't happen this year, then it will be next year, because I think the first test of shooting down a tactical ballistic missile is supposed to take place in the time frame of 2008, and so that'll be the first time that what they call a "megawatt class" (laser gets tested).

And just to be clear--sometimes when we say Airborne Laser we're talking about the plane, and then it's also a description of a weapon itself.
Beason: That's right. What they really mean by the Airborne Laser is not the 747 that carries it, but the entire weapons system, that is the COIL laser--COIL stands for chemical oxygen iodine laser--the modified 747, as well as all the associated lasers that are on board. There are several other lasers that are onboard the Airborne Laser besides the weapons-class laser. There is a tracking laser, a laser that actually acquires the target, tracks the target. There is another laser that is there for the purpose of what is known as adaptive optics. If we were just to shoot the laser out over a distance without the beam being modified in some way, then the atmosphere would scatter the light; it would absorb the light, and by the time the beam hits the target, the beam would be in a very nonoptimum configuration--that is, it wouldn't be the most powerful energy density that you can put on a target. By using adaptive optics, what the Air Force has managed to do is to precondition the beam, so that it takes all the abnormal characteristics of the atmosphere out of the beam before it's propagated, and so by the time the beam reaches the target, it evolves into a very pristine, nearly optimal shape.

All aspects of this have been tested either in the laboratory or in the field. It's never really been put together as one package, and especially on the Airborne Laser as one system.

Now, this thing is also going to take a lot of juice, right? Everything you need to power the lasers is going to be able to fit in the 747?
Beason: Absolutely, and that's why you need a 747 to carry all the chemicals necessary to generate the laser light. Basically, the laser is generated by the transition of an excited iodine atom going from its excited state to a nonexcited state, but in order to get that iodine to the excited state, there is a chemical reaction that has to occur that transfers energy from oxygen to the iodine.

With the ABL, will that be a single-shot weapon, or would you be able to fire it multiple times--or is it too early to tell?
Beason: You'll be able to fire multiple times, and basically when you lase a target, you have to lase it for some certain amount of time in order to get the weapon effect. The effect that it wants to gain on these tactical ballistic missiles is that it heats up the skin of the missile and then the internal pressure of the fuel tank actually causes the missile to explode. Also what you want is to be able to go from one target to the next in a very quick amount of time, because you don't want to give the enemy the ability to fire off three or four missiles and to overwhelm your system, so it has to have the ability not only to lase for a long time but also to jump from target to target.

(A directed energy device is) an inherently defensive weapon and not an offensive weapon, because you can't attack large amounts of areas.

And there are other laser weapons that are being studied, smaller-scale ones--there's the tactical laser, and then there's Zeus, which is not a weapon per se.
Beason: Right, the Advanced Tactical Laser is actually a smaller laser than the ABL that is being put on a smaller tactical platform. Right now, they're looking at a C-130, but it could possibly be put on a helicopter. That's a laser that is in a class that is greater than 50 kilowatts, so it's a few orders of magnitude less powerful than the Airborne Laser. Its missions are designed to supplement what the Airborne Laser is doing, that is, to help with special operations and antiterrorism and that, but at very close distances, that is, kilometer range versus the many hundreds of kilometers range that the Airborne Laser is working on.

The Zeus is actually a solid-state laser developed by the Army to heat up mines, to be able to clear minefields at a distance. In fact, the Zeus was deployed to Afghanistan, and several hundred mines were cleared by the use of this tactical weapon. There is another one called the THEL, or the Tactical High Energy Laser, that was developed for the Army, and this laser had actually shot down Katyusha rockets in White Sands Missile Range, and after over 30 Katyusha rockets were shot down, they decided to see if they could also shoot down mortars and artillery shells, and they were successful on that.

Even though all these systems have different energies and different power levels--and some are strategic, some are tactical--some of the attributes that they all have in common, and we're going to see this with high-power microwaves, is that they all travel at the speed of light and so they can deposit their energy instantaneously. Light travels 186,000 miles a second and so that means it can go around the Earth more than seven times in less than a second, and it's extremely accurate--and so therefore it's an inherently defensive weapon and not an offensive weapon, because you can't attack large amounts of areas.

The other system I want to talk about is Active Denial, the microwave weapon--this is a very different kind of system, obviously, than the laser?
Beason: The Active Denial is actually not a microwave, but what they call a millimeter wave. Microwaves are 70 times larger than millimeter waves. The Active Denial system operates at about 100GHz, and what scientists discovered a few decades ago was that millimeter wave energy at about 100GHz is absorbed about a third of a millimeter into the human skin, and so it doesn't penetrate the body, but what happens is that this energy is perceived by the body as heat. The nerve endings perceive a near instantaneous increase in heat and in fact the effect is kind of like opening up a supercharged oven and feeling this heat all over your body.

Now what the body does when it experiences this is undergo something called the "flee effect"--the body just wants to get away from it; it wants to flee. When the person moves away from the millimeter waves that are causing this effect, the effect goes away, so what the military is doing now, it is investigating using this Active Denial effect as a way to what they call "assess intent."

The idea is that, as a crowd starts to descend upon an embassy, let's say, that at first you have loudspeakers broadcasting "stay away," and then when the crowd gets closer and closer, that you can expose the crowd very selectively to this Active Denial effect. If the people turn and run away, then you know that they perhaps didn't have the intent to storm the embassy, but if they turn around and start to come back again and then you again expose them to millimeter waves, then the intent is surely one that they want to take over the embassy. And so at that time, as they get closer and closer, you can use lethal force to stop it.

Now, you've actually experienced the Active Denial System.
Beason: Yes, I did. It was back in 2001, and it was when they had first approved Active Denial for human testing. It was one of the most amazing experiments that I have had the privilege to participate in. At the time they were just exposing people's backsides to the millimeter waves, because in very strict human protocol testing, you just want to take it one step at a time. At the time I had to jump out of the way of the beam within an extremely short amount of time and, even though I was scheduled for two more tests, I was kind of reluctant to go back and do that again because I still had the memory of what it felt like, even though I didn't show any signs of being exposed to it.

Now, before I underwent the testing, I did a lot of research, because I didn't want to do the testing without knowing what was happening. I did discover that because the beam was at the millimeter part of the electromagnetic spectrum that it wasn't energetic enough to cause any type of carcinogenic effects--that is, carcinogenic effects occur with exposure to UV radiation, because the UV radiation is energetic enough to ionize some of the cells that make up the human body, but millimeter waves are too low in energy to do this--in fact it's much, much lower than sunlight or even infrared radiation, and also the amount of time that it takes to produce the Active Denial effect is much, much less than any time that it would take to cause any physiological effects.

Lasers are ready to go to the battlefield any day now, Active Denial could go to the battlefield any day.

So, in effect this works, to use science fiction terminologies, as a force field?
Beason: In fact, the joke was "phasers on stun"--you don't really stun people with this, but you can use a sweeping motion if you want to push people away as if you had a virtual force field there.

How much energy does this kind of system draw?
Beason: Active Denial has actually been put on a Humvee. I can't really say what the power levels are because that's classified, but you can actually drive around the Active Denial unit on this Humvee and have enough energy, so to speak, for missions that last a very long time--long enough to be of military significance. It's what we call a tactical system, that is, it's short-range, and remember I said an inherent advantage of directed energy is that it's really defensive because you cannot spread the Active Denial system over a large area, over a large crowd--it has to go from person to person to create this effect. You could sweep it back and forth, but you can't do it over a very large area--you can't imagine doing this over a city block or a city or anything like that.

Your book also talks about high-power microwaves--so that's different from the millimeter wave.
Beason: The difference here is that high-power microwaves are a type of directed energy that doesn't affect people but rather affects electronics. The difference is that if you look at the maturity with lasers, millimeter waves and microwaves, microwaves are the least mature type of technology. Lasers are ready to go to the battlefield any day now, Active Denial could go to the battlefield any day, but microwave research, it's going to take one or two decades until we get to the technical maturity to be able to put it on the battlefield.

Any other goodies coming out of the labs?
Beason: Not that I can talk about. (Laughs) Some of these things, like Active Denial when it was declassified back in 2001, it was a very low-key affair, but it is something that I think would completely revolutionize the way that we conduct warfare, if the military would just simply make the investments to accelerate this to the battlefield. But the problem is not with the military not wanting it; it's with the bureaucrats who are responsible for acquiring the system, because what they tend to do is to invest not in new revolutionary types of weapons, but rather evolutionary types of capabilities. They like to increase the capability of a present-day weapon system by only 1 to 5 percent a year because they know that it works, rather than spending a whole lot of money on a new system that they are not sure would work.

What kind of budget are we talking about for these systems like ABL?
Beason: ABL has been $300 (million) to $500 million a year over the past decade, and high-power microwaves is about an order of magnitude below that, about $30 million or so. The difference there is that the Airborne Laser is a weapons system, and that's right on the order that you would expect a major strategic weapons system to be funded at, but high-power microwaves are still in the laboratory.