For this year’s Fourth of July feature, The Cipher Brief revisits its coverage on electromagnetic railguns. Capable of firing projectiles at speeds of Mach 7 to strike targets over 100 miles away, electromagnetic railgun systems for the Navy and the Army are now reaching the final stages of development and could become operational for roles ranging from missile defense to naval surface warfare within the next few years. The Cipher Brief talked with Scott Forney, President of the Electromagnetic Systems Group at General Atomics to find out just how close this revolutionary technology is to practical application.
The Cipher Brief: What new advantages does the Blitzer Electromagnetic Railgun system provide for modern warfare, and what role has General Atomics-Electromagnetic Systems Group (GA-EMS) played in the development of this technology writ large?
Scott Forney: Let me tell a story that gives a picture of where we are today. General Atomics has been in the pulse power business for so many applications over the last 50 years that we had to get used to moving around and controlling thousands of kilowatts of energy in split seconds.
So, in the 1990s, we started working on new motor technology, which ended up being the catapult for new aircraft carriers called EMALS – Electromagnetic Aircraft Launch System – and in developing that technology we realized that the advent of the semiconductor and the shrinking packages for these electronics had become incredibly cost-effective. That’s when GA really started looking hard at what can we do for a modern-era railgun system.
Our first introduction to the railgun technology came in the 1980s when GA-EMS worked on the Reagan-Era “Star Wars” program, but at that time, if you wanted a pulsed power system, it would be the size of a Costco warehouse. However, over the last eight years, we’ve shrunk the footprint for equivalent energy output by a factor of eight. Now, this power system is no longer something that you need to fit into a Costco warehouse, it’s something that you can integrate into a naval vessel or carry on transportable trucks for the Army. That changed everything, because what was an interesting science experiment a decade ago is a viable system today. This was made possible by downscaling the microelectronics and the semiconductors used in the system, as well as building very small and reliable capacitors, which GA-EMS is probably the world leader in.
On to the electromagnetic railgun, the system basically pumps millions of amperes into two rails, which are separated by non-conducting ceramic material. In order to launch a hybrid missile – many people call it a projectile – electrically, you guide the projectile via riders called sabots. Once you have that you basically short the two rails in the railgun, and the current flowing through the armature – the conductive material connecting the two rails – is what accelerates that hybrid missile to 5,000 miles per hour in a fraction of a second, while the armature flies a couple hundred meters in the air and falls down.
This technology – shaping the armature into the railgun and developing a railgun that allows you to repeatedly fire a hybrid missile out – all of that was developed in the last decade to show that we could get a lot more launches out. The result today is something that you can count on for repeatability. Now, based on the testing we’ve done at General Atomics, we’ve done about 160 launches and we don’t see any wear in the railgun.
Finally, the last step in this whole process is a missile that can handle the incredible environment of a railgun. You’re shooting that missile out so fast, and at such a high rate of acceleration, that you have very high G-force loads, huge amounts of acceleration that all the electronics, and batteries, and control systems have to withstand. Therefore, it was very important to get the microelectronics hardy enough to survive that environment. If you can get them to do that repeatedly using commercial-like technology, suddenly you have a very inexpensive round, and indeed that’s what General Atomics has done. We started developing our own hybrid missile in 2012, and we now have a missile with electronic systems that can survive this very intense environment of high G-forces, high temperatures, and a very strong electromagnetic field.
By building this with technology that is readily available today you get a system that is two orders of magnitude less expensive than today’s missiles. Thus, when you start thinking about the adversary being able to launch very inexpensive missiles at the United States and our allies, possibly in swarms, we will soon be able to respond with $25,000 hybrid missiles from a railgun rather than multimillion-dollar conventional missiles.
This is the big change, and it’s why General Atomics has invested so much of its own internal money to ensure that we could make this a reality. Indeed, this year is our big test year. We are now testing at the 10-megajoule scale, which we think is the sweet spot for both Army and Navy applications; we now have our fifth-generation pulsed power system just about complete; we have our third-generation railgun built; we actually have a new mounting system that allows us to elevate and azimuth the gun to go after targets, and we’ve tested a radar system.
We are very excited about this technology, and I think it is going to revolutionize our warfighters’ capability. For once we’ll have a truly low-cost answer to any missile system out there. That is a huge deal.
TCB: Could you go through that system, the challenges you’ve had, and how it differs from the project that you’re working on for the Navy?
SF: To separate the two, we’ve developed a large 32-megajoule scale railgun for the Navy, which can reach about 125 miles of accurate range. We’ve also developed three generations of pulsed power in support of the Navy.
You have two pieces of this technology. First, as we’ve covered, it’s cost-effective, but it also has to be something where you can do burst rounds to take on swarms of targets, and you have to have pinpoint accuracy. We have been able to achieve all of this and the government is currently checking our analysis independently. We’re also creating a pseudo cruise missile of our own later this year so that we can engage it dynamically in real time, which will be the end of the test program that we’re still funding this year.
The biggest challenge of all this, to be candid, was how to accurately control the projectile, because we’ve inverted the traditional equation. With every current missile system, you start off slow and by the boost phase you go faster and faster. By the time you get to target that’s where you’re at the speed you need for the intercept. With a railgun, we’re up to speed the second we leave the barrel, and we hold that speed for a great deal of time so it is a very hard thing to calculate the guidance and navigation control systems for.
Over time, we developed that control system but one of the biggest remaining problems was that all this navigation is occurring in a hypersonic environment. To help solve that problem, we bought a boutique engineering firm called Miltec last year that focuses on hypersonic weapons systems, and this gave us the final piece of the puzzle.
Without question, developing a projectile that could survive this kind of harsh environment was the most difficult part of the project and that work is completely internally funded. We decided to go that way because we wanted to integrate all the technology instead of being teamed with some of our competitors. This was a risky move and it cost us more than $50 million but we decided that was the fastest way to be successful.
TCB: Let’s talk about the land-based Blitzer system. Can you walk me through how that will work?
SF: As I said, one of the biggest problems with the railgun for missile defense was achieving pinpoint accuracy at such high speed. So instead of trying to hit incoming missiles directly with our hybrid missile, we have packed the front end of our projectile with tungsten impactors. Those tungsten impactors are very dense, and when they end up impacting with an incoming target, you can think of it as a tungsten shield. It is essentially a tungsten shotgun shell at the tip of the projectile, which is very lethal if you can get it in the way of whatever you’re shooting at.
'Blitzer' firing - Image courtesy of General Atomics
TCB: How about the naval system?
SF: No difference actually. The only difference is we had to develop the system so it was truly transportable. That caused us to really shrink the system down. In the last three years, we’ve actually been able to double the energy density, which is a very big deal. Getting it down to that size allowed us to get it on HEMTTs (Heavy Expandable Mobile Tactical Truck) for the Army – if they choose to use HEMTTs – and it also gives us the option to deliver a portable railgun system that can fit on something like the Littoral Combat Ship.
TCB: It’s interesting that you bring up power density because this has been one of the major criticisms of the railgun, that its power needs are so great a ship would need to stop and divert all power in order to charge and fire the weapon. Is this true?
SF: Not true.
I know there are many who think that’s what the design would have to be, because you need to charge the capacitors to fire and therefore you would need a huge integrated electric propulsion or power system to charge those capacitors. But one expertise of General Atomics, specifically the Electromagnetic Systems group, is that we have developed very advanced lithium-ion battery systems. The Navy had a big problem back around 2007 with the Advanced Swimmer Delivery System, in which the lithium ion batteries caught on fire and they couldn’t put it out for several days. That’s because lithium ion is so energy dense that, if a fire occurs, it is very difficult to put out, and you need thousands upon thousands of these cells to operate a railgun.
General Atomics has, for years, been investing in ways to make those batteries safe. In essence, we found a way to control that thermal runaway. Based on this technology, our idea at GA-EMS is that we will charge up these batteries, and then we can release one shot at a time out of the batteries into the capacitors very quickly. With our unique system, if somebody says that they want 40 rounds stored, we can electrically store 40 rounds in the batteries and then charge up those capacitors every time we shoot the railgun. Meanwhile, over time you can get a trickle charge as you run the motor, just like in a car.
So instead of needing tens of megawatts of power, we need hundreds of kilowatts and that’s it.
TCB: Speaking about the timeframe then, if you had to make a guess, when do you think the first Blitzer railgun might become operational?
SF: So, our test program will drive that answer, and our plan is to demonstrate the feasibility of shooting down a moving round – that’s the pseudo cruise missile that we’re developing – by Christmas. Once that happens, I think we would be in a position to demonstrate our development system by the end of this year and move on to a tactical system. At the end of the day, we could be fielded within three years.
TCB: Railgun technology has been around for a long time and the theoretical proposals for its use vary from orbital launch to igniting fusion reactions. For you, what is the most exciting aspect of this technology, and will GA pursue some of these longer term moonshot ideas?
SF: That’s what the company has been built on, so naturally we’re interested in what comes next. There are some technologies that we’re working on, which I’m not able to talk about today. However, we have been asked twice by NASA if we could use an electromagnetic launch system to launch satellites or even payloads the size of a space shuttle. So we’ve done designs which show that yes, this is very feasible to do. And we are also in the nanosatellite business, we’re the only provider of satellites to the U.S. Army today, and we’re looking at low-cost ways to get those satellites into orbit.
I know everyone’s looking at what Elon Musk is doing at SpaceX in terms of lowering launch costs but, when you think about it, it’s not a stretch to say we could use electromagnetic technology to launch these satellites. So we’re evaluating what that path could look like, and I can say that we have been studying several options to launch satellites and similar-looking vehicles into space.
At the end of the day, we’re not trying to drive out the larger missile systems, we’re just trying to give the Army and the Navy more options for layered defense so that you don’t have to use a $10 million missile when you could use a $25,000 railgun projectile.
It’s just awesome, fantastic stuff and we’re really excited about this technology.
