From The Editor | March 27, 2017

How Far Away Are Non-Lethal, Weaponized EMPs?

Ed Biller

By Ed Biller, Editor

The mechanism depicted above is for a 400 km high-altitude burst EMP: gamma rays hit the atmosphere between 20-40 km altitude, ejecting electrons which are then deflected sideways by the earth's magnetic field. This makes the electrons radiate EMP over a massive area. Because of the curvature of earth's magnetic field over the USA, the maximum EMP occurs south of the detonation and the minimum occurs to the north. The illustration is from the 1994 U.S. Army report ADA278230, "Nuclear Environment Survivability."

On July 9, 1962, the United States launched a W49 thermonuclear warhead from Johnston Island in the northern Pacific Ocean, and detonated it at an altitude of 250 miles, creating an explosion equivalent to 1.4 million tons (1.4 megatons) of TNT. The resulting nuclear electromagnetic pulse (EMP) was much larger than expected, knocking out streetlights and telephone service in Hawaii, almost 900 miles away. You can see the test film here.

Imagine the effect that EMP would have had on a modern population center, a place dependent upon electronics to function and, indeed, to survive. Governments and scientists across the globe are pondering that very scenario — either in terms of creating it, or defending against it — minus the nuclear blast. An effective, non-lethal EMP would be invaluable on the modern battlefield, crippling an enemy while minimizing civilian casualties. But just how far away are weaponized EMPs from effective, affordable deployment?

The answer: Closer than one might think, depending on the scale of the assault. Peter Pry, director of the EMP Task force — a privately run, unfunded, bipartisan congressional commission — summed up the problems with creating a large EMP weapon to Vice: “Besides the weight, and the cost of whatever you use to generate that kind of electricity — a capacitor, a large amount of batteries, or whatever power generation method — the cost would be so high, but the damage you can do with it would be so limited, that other much cheaper methods might be more efficient when it comes to damaging the area that you're targeting.”

“Cheaper” large-scale methods could include traditional explosives strategically placed around enemy power grids, or high-altitude nuclear EMP weapons (HEMPs). Neither of those approaches is prudent if you’re trying to minimize loss of life, though, so militaries have begun to look at smaller-scale technologies to disable enemy electronics. These weapons offer the additional advantage of being able to target more specific threats, from UAVs and missiles to vehicles and radar systems.

An EMP can be created in several ways — as a radiated, electric, or magnetic field, or through a conducted electric current. Both Russia and China are working to develop electronics-frying microwave weapons, which work by bombarding a target with energy pulses between 300 and 300,000 MHz.

China’s microwave weapon is small enough to be fitted to air or land vehicles, reports Popular Science, and its development earned researchers at China’s Northwest Institute of Nuclear Technology the country’s National Science and Technology Progress Award. Russia, meanwhile, is preparing a similar system for use in unmanned versions of its sixth-generation combat aircraft, reported Russian news agency TASS last year. Vladimir Mikheev, a director of state-owned Russian electronics firm KRET, explained that the platform is only planned for unmanned aircraft because its microwave pulses will be so powerful as to be detrimental to the health of pilots.

The U.S. is looking at both long- and short-range counter-electronics weapons. Last March, the U.S. Air Force (USAF) rebooted development of its Counter-electronics High-Power Microwave Advanced Missile Project (CHAMP). On Oct. 22, 2012, Boeing announced a successful test of the CHAMP missile, stating that it took out seven different targets before self-destructing over empty desert. However, the project lay dormant until last year, when Raytheon received a $4.8-million USAF contract for directed energy activities. The contract includes integration of the CHAMP payload onto the conventional variant of the Boeing AGM-86B air-launched cruise missile (ALCM).

Then, in November, the U.S. Department of Defense (DoD) released an Army research proposal calling for development/demonstration of “innovative, cost-effective, munitions-based electronics systems that can deliver non-destructive, non-kinetic RF effects against a wide range of electronics, critical infrastructure, and computer-based systems.” The proposal calls for initial designs to fit in a 155-mm artillery projectile, though the eventual goal is to shrink the weapon to the point where a single shell can carry multiple submunitions.

The 155-mm artillery piece currently in service with the U.S. Army and U.S. Marine Corps, the M777 Howitzer, has an effective range of 25 miles when firing the Raytheon-developed, GPS-guided M982 Excalibur artillery shell. Thus, an EMP weapon fired from the same platform likely would have similar range.

To defend against EMP attacks, engineers have created metal sheets, plates, and tape, as well as conductive paints and even EMS-shielded spray-on concrete. For the civilian attempting to protect home electronics, a Faraday cage is an affordable option. On a national level, both the U.S. government and utility companies have contingency plans in place in case of a large-scale EMP, though some of these plans were built around the much more realistic possibility of geomagnetic disturbances (GMDs) caused by solar flares.

For example, the Spare Transformer Equipment Program (STEP) is among a handful of initiatives to help the electric industry — in both the U.S. and Canada — bounce back quickly in the event of a transmission outage (such as one caused by a terrorist attack). STEP coordinates utilities, increasing their inventory of spare transformers and streamlining the process of transferring those transformers to affected utilities.

Also, while dated, a 2008 report by the EMP commission discussed above gives insight into how the U.S. would recover from a large-scale EMP attack generated by a high-altitude nuclear explosion, so it’s not as if the issue was not considered well before threats of sci-fi technology surfaced. Heck, The U.S. government in 2015 returned to its underground Cheyenne Mountain facility in Colorado —which was shut down in 2006 — and inked a $700M contract with Raytheon to update its electronic systems.

“Because of the very nature of the way that Cheyenne Mountain is built, it’s EMP-hardened. It wasn’t really designed to be that way, but the way it was constructed makes it that way,” stated Adm. William Gortney, commander of U.S. Northern Command and NORAD at the time. Adm. Gortney, who retired in June 2016, added that a hardened Cheyenne Mountain is intended to preserve critical communications in the event of an EMP attack.

Still, the best defense against EMP attack remains prevention. In the case of focused assaults, defense contractors and researchers must continue to develop novel EMP-shielding technologies — making them lighter, more flexible, more effective, and less expensive. As for large-scale EMP attacks, the best (in terms of cost and convenience) way to generate such a pulse is a high-altitude nuclear detonation, a situation for which there is no grand defense, only a combination of coordinated defenses, including those mentioned above.

Even in the event of such an attack, a lot of false information has been disseminated, ranging from exaggerated, catastrophic death tolls to misinformation about the types of devices that will be affected, and to what extent. A report dispelling many of these myths was compiled by Metatech for Oak Ridge National Laboratories, and the version linked here contains additional commentary by Jerry Emanuelson of Futurescience, LLC. 

What are your thoughts on counter-electronics weapons? What is their best or most interesting application, and what defensive strategies or technologies show the most promise? Let us know in the Comments section below.