From The Editor | June 27, 2024

Directed Energy Weapons: From The Mirrors Of Archimedes To Iron Beam

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By John Oncea, Editor


The U.S., China, France, Germany, the U.K., Russia, India, Israel, and Pakistan are all working to develop military-grade directed energy weapons. While mostly in the developmental stage, they are fast becoming the practical, high-performance military option of tomorrow.

Directed energy weapons (DEWs) are a type of ranged weapon that, much like guns, artillery, rockets, and torpedoes, engage targets beyond hand-to-hand distance. They accomplish this using focused electromagnetic energy and encompass high-energy lasers and high-power electromagnetic systems, including millimeter wave and microwave weapons.

Like all ranged weapons – which researchers believe were first used as far back as 300,000 years ago – DEWs can damage or destroy a target. Unlike other ranged weapons, DEWs can neutralize targets such as drones, rockets, artillery, and mortars with temporary and reversible effects by degrading their electronic components and guidance systems rather than destroying them.

DEWs also can penetrate superficial skin layers by projecting a focused beam of electromagnetic waves at a high frequency and short wavelength resulting in pain and burning without causing ionizing radiation. Other non-lethal results of the use of DEWs include difficulty breathing, disorientation, nausea, vertigo, and systemic discomfort. 

So, what exactly are directed energy weapons, and were they really used by Archimedes?

How DEWs Function

According to the Defense Systems Information Analysis Center (DSIAC), different types of DEWs operate within specific electromagnetic spectrum ranges, encompassing all forms of light categorized by wavelength. The unique properties of different wavelengths influence penetration capabilities through various materials, like metal or biological tissue.

DEWs utilize a variety of technologies, including lasers, microwaves, particle beams, and sound beams. These weapons damage targets by focusing on highly concentrated energy rather than solid projectiles. DEWs offer several advantages over conventional weapons:

  • Precision: Light and other forms of directed energy are unaffected by gravity, wind, or Coriolis force, allowing for highly accurate targeting.
  • Speed: Lasers and other DEWs travel at the speed of light, making them suitable for intercepting fast-moving targets like missiles.
  • Logistics: DEWs eliminate the need for traditional ammunition, relying instead on a power source, which can simplify supply chains.
  • Stealth: Many DEWs operate silently and invisibly, especially those outside the visible spectrum, making them difficult to detect.

Other advantages of DEWs include the ability to precisely target specific points, lower cost per use, unlimited magazine capacity, rapid target engagement, minimal collateral damage, and through-wall capability.

Perhaps the most well-known DEW, high-energy lasers HELs emit a concentrated beam of light, typically in the infrared to visible spectrum. These lasers can be continuous or pulsed, delivering power outputs as low as 1 kilowatt. Their precision allows them to target and melt metal, plastic, and other materials. Examples include the UK’s DragonFire, a 50-kW class laser capable of engaging targets within line-of-sight, expected to be operational by 2027.

Millimeter wave weapons operate in the 1 to 10-millimeter wavelength range, delivering more than 1 kilowatt of power. They can affect multiple targets simultaneously due to their broader beam. 

High-power microwave weapons generate microwaves with longer wavelengths than lasers or millimeter waves. They’re capable of producing more than 100 megawatts of power and can disrupt multiple targets within their larger beam area. 

According to Intergalactic, taking DEWs from development to operational deployment presents challenges. For instance, their effectiveness diminishes with increased distance and adverse atmospheric conditions.

Operationally, DEWs may have more limited utility than initially believed since wide-beam DEWs can affect both friendly and enemy assets within the area of impact and they may struggle against well-shielded targets or in environments where line-of-sight is obstructed. Additionally, international norms and regulations related to DEWs are in their infancy and do not offer a clear framework by which to mitigate the risks of their use. Furthermore, there are open-ended questions about the ability of existing industrial supply chains to produce DEW capabilities at scale.

DEWs may offer practical air and surface defense applications and are best oriented to counter slower-moving and swarm threats such as drones, rockets, artillery, and mortars by disrupting or destroying their electronic components and guidance systems. DEWs are frequently cited as having potential for missile defense, including against ICBMs, but the technological challenges to such applications are currently prohibitive.

The U.S. Department of Defense claims that DEWs have the potential to counter slower-moving missile threats such as anti-ship and land-attack cruise missiles, the basic logic being that DEWs are a lower-cost way to defeat less advanced aerial threats that would allow more expensive interceptors to be saved for the faster and more troublesome ballistic threats that DEWs cannot reliably engage. It’s also possible that DEW capabilities could be used against enemy surface boats and autonomous maritime vehicles, as well as adversarial intelligence, surveillance, and reconnaissance capabilities.

2,237 90 Years Of Directed Energy Weapons

Historical research is challenging due to problems of sources, knowledge, explanation, objectivity, and the peculiar problems of contemporary history. All of this applies to trying to nail down a DEW-developmental timeline, a task further complicated by the amount of secrecy surrounding the technology. What follows, then, is a loose summation of the development of DEWs, starting with their alleged use during the siege of Syracuse in ancient Greece around 212 BCE.

What is known about this siege, according to Britannica, is the Romans stormed the Hellenistic city of Syracuse and, after many months, were able to overcome the Syracusans’ defenses and gain control of the entire island of Sicily.

Knowing the siege would prove difficult, the Romans brought unique devices and inventions such as the sambuca, a floating siege tower with grappling hooks, as well as ship-mounted scaling ladders that were lowered with pulleys onto the city walls. They needed all of this technology to overcome the defensive devices put in place by Archimedes, the prominent inventor and polymath who met his demise at the siege’s conclusion.

One of the devices historians agree Archimedes used was the Claw of Archimedes, a crane-operated hook that lifted the Roman ships out of the sea before dropping them to their doom. The Syracusans also used fire from ballistas and onagers mounted on the city walls, frustrating the Romans and forcing them to attempt costly direct assaults.

It is also alleged, first in historical writings by Lucian of Samosata and Galen of Pergamon in the second century CE, that Archimedes used polished mirrors to focus sunlight on the sails of Roman ships, setting them on fire. This is an allegation that no contemporary Greek or Roman account supports. Furthermore, modern experiments such as those conducted by the MythBusters found that Archimedes’ “death ray” was likely impractical and more myth than reality. That aside, polished mirrors could have been considered and the story serves as the first-ever attempt – at least conceptually – to harness focused energy for military purposes.

Incidentally, today, “Both engineering calculations and historical evidence support the use of steam cannons as ‘much more reasonable than the use of burning mirrors,’” according to NBC News. “The steam cannons could have fired hollow balls made of clay and filled with something similar to an incendiary chemical mixture known as Greek fire to set Roman ships ablaze. A heated cannon barrel would have converted barely more than a tenth of a cup of water into enough steam to hurl the projectiles.”

Directed Energy Weapons And World War II

Starting in the 1930s and running up to and through World War II stories were circulating that an engine-stopping ray was being developed and/or already developed by first the Germans, then the British. They appeared to have originated from the testing of the television transmitter in Feldberg, Germany, according to R.V. Jones’ 1978 book Most Secret War: British Scientific Intelligence 1939–1945. To prevent interference from electrical noise caused by car engines, guards would halt all traffic in the area for about twenty minutes during a test.

When the story was retold with events reversed, it created a narrative in which tourists’ car engines stopped first, and then they were approached by a German soldier who instructed them to wait. The soldier returned a short time later to inform them that their engine would now work, and the tourists drove off. These stories were circulating in Britain around 1938, and during the war, British Intelligence revived the myth as a British engine-stopping ray in an attempt to deceive the Germans into researching a fictional invention, thereby diverting German scientific resources.

During the 1940s, according to Weird Weapons: The Axis, Axis engineers developed a sonic cannon in the form of a methane gas combustion chamber leading to two parabolic dishes pulse-detonated at roughly 44 Hz that could cause fatal vibrations in its target body.

The amplified sound from the dish reflectors caused vertigo and nausea at distances of 220–440 yards by vibrating the middle ear bones and shaking the cochlear fluid within the inner ear. At distances of 160–660 feet, the sound waves could affect organ tissues and fluids by repeatedly compressing and releasing compressible resistant organs such as the kidneys, spleen, and liver. This had little detectable effect on malleable organs such as the heart, stomach, and intestines. Lung tissue was affected only at the closest ranges as atmospheric air is highly compressible and only the blood-rich alveoli resist compression.

In practice, the weapon was highly vulnerable to enemy fire with rifle, bazooka, and mortar rounds easily deforming the parabolic reflectors, rendering the wave amplification ineffective.

DEWs being investigated at the same time by the Nazis included X-ray beam weapons developed under Heinz Schmellenmeier, Richard Gans, and Fritz Houtermans. According to the Nevington War Museum, they built an electron accelerator called Rheotron to generate hard X-ray synchrotron beams for the Reichsluftfahrtministerium (RLM).

Invented by Max Steenbeck at Siemens-Schuckert in the 1930s, these were later called Betatrons by the Americans. The intent was to pre-ionize ignition in aircraft engines and hence serve as an anti-aircraft DEW and bring planes down into the reach of the flak.

1980: Reagan’s Star Wars Program

On March 23, 1983, Ronald Reagan announced the $30 billion Strategic Defense Initiative (SDI) as a way to protect the U.S. from nuclear ballistic missiles. Often referred to as “Star Wars,” the program sought to render nuclear weapons obsolete by leveraging advanced technologies, including DEWs such as lasers and particle beams, according to the U.S. Department of State.

The SDI Organization (SDIO) was established in 1984 to oversee the development of these technologies, according to the Notre Dame Law School Journal of Legislation. The program involved extensive research at national laboratories, universities, and private industry. Despite significant investment, the American Physical Society concluded in 1987 that the technologies required for an effective DEW system were still decades away from being feasible for several reasons, including:

  • Technological Feasibility: Many of the proposed technologies required significant advancements before they could be considered viable for missile defense.
  • High Costs: The program was extremely expensive, with estimates running into the trillions of dollars for full-scale development and deployment.
  • Strategic Concerns: Critics argued that the SDI could destabilize the doctrine of mutual assured destruction (MAD) and potentially provoke a preemptive strike from adversaries like the Soviet Union.

Although the SDI did not achieve its ambitious goals, it spurred significant advancements in various fields, including particle physics, supercomputing, and advanced materials. Some of the research and technologies developed under the SDI have been integrated into subsequent defense programs including the Neutral Particle Beam Accelerator (NPB) developed by Los Alamos National Laboratory. According to the Smithsonian Air and Space Museum, NPB was among several DEWs examined by the Strategic Defense Initiative Organization for potential use in missile defense.

In July 1989, the accelerator was launched from the White Sands Missile Range as part of the Beam Experiment Aboard Rocket (BEAR) project, reaching an altitude of 124 miles and operating successfully in space before being recovered intact after reentry.

The primary objectives of the test were to assess NPB propagation characteristics in space and gauge the effects on spacecraft components. Despite continued research into NPBs, no known weapon system utilizing this technology has been deployed.

Though the strategic missile defense concept has continued to the present under the Missile Defense Agency, most of the DEW concepts were shelved. But they were not forgotten.

During the Iraq War, electromagnetic weapons, including high-power microwaves, were used by the U.S. military to disrupt and destroy Iraqi electronic systems and may have been used for crowd control. Then, the first known use of DEWs in combat between military forces was claimed to have occurred in Libya in August 2019 by Turkey, which said it used the ALKA DEW.

The 21st Century: Iron Dome, Iron Beam, And Beyond

The Iron Dome, used by Israel for missile defense, relies on intercepting rockets with physical projectiles. However, according to Rutman IP, laser-based systems like the Iron Beam could revolutionize missile defense by offering cost-effective, precise, and rapid responses to threats.

Officially known as Magen Or (Light Shield), Iron Beam is a laser-based air defense system designed to complement the Iron Dome by targeting short-range threats like rockets and drone short-range rockets, artillery, and mortar bombs, as well as intercept UAVs.

The Economist writes that Iron Beam’s primary advantage lies in its cost-effectiveness and potentially unlimited magazine. While traditional interceptor missiles like those used in the Iron Dome system can cost tens of thousands of dollars each, Iron Beam's laser shots cost only a few dollars in electricity generation. This makes it an attractive solution for countering the high-volume, low-cost threats often employed by adversaries.

Being developed by Rafael Advanced Defense Systems, Iron Beam utilizes advanced mirror configurations to focus a powerful laser beam on targets up to 4 miles away. The system maintains impressive precision, capable of focusing 100kW of power on an area the size of a coin at a distance of 6 miles. However, its effectiveness can be limited by weather conditions, as moisture and particles in the air can absorb laser energy.

Originally conceived as a mobile system, Iron Beam has been adapted for integration with the existing Iron Dome infrastructure to reduce complexity and address power supply concerns. The Israeli military is accelerating the deployment of Iron Beam, with plans to have it operational by the end of 2025.

In addition to its land-based applications, Rafael has unveiled a Naval Iron Beam variant designed to protect ships against drone swarms and anti-ship missiles. This naval version is expected to be operational within four to five years.

While Iron Beam shows great promise, it faces some challenges. The system requires a certain dwell time to neutralize targets, making it more effective against slower threats like drones rather than rapid barrages of rockets. Additionally, the up-front cost of deploying Iron Beam batteries is significant, and evaluations are ongoing to determine if its performance justifies the investment.

As Israel continues to refine and deploy Iron Beam, other countries, including the U.S., are exploring similar laser defense technologies, highlighting the growing interest in DEWs for air defense.

The Future Of DEWs: Exotic Alternatives

Space-based lasers have evolved to incorporate ground-based lasers reflected off space-based mirrors, writes Rutman IP. This concept envisions using three mirrors on geostationary satellites to enable a ground-based laser to target any location on Earth’s surface. The ground-based approach allows for larger, more powerful lasers than those that can be deployed in space.

Free Electron Lasers (FELs), according to NASA, represent a significant advancement in laser technology. These devices use technology from particle accelerators to generate high-energy X-ray lasers. FELs operate by sending high-speed electrons through an array of magnets, causing them to wiggle or undulate. This motion results in the emission of radiation perpendicular to acceleration, with the wavelength determined by the magnet spacing and electron speed.

Another innovative concept, writes Rynam IP, is the plasma bolt. This technology uses an intense laser beam to create a conductive plasma channel in the air. Once established, this channel can carry an electric current, functioning as a directed lightning bolt. The U.S. Army's Picatinny Arsenal in New Jersey reportedly tested this technology in 2012.

The plasma bolt concept works by using a laser beam intense enough to strip electrons from air molecules, creating plasma. While flying objects are typically electrically isolated, applying extreme voltage or a directed electromagnetic pulse (EMP) could potentially damage their electronics or detonate electrically sensitive explosives.

These advancements in laser and directed energy technologies represent significant developments in space-based and ground-based defensive and offensive capabilities. However, it's important to note that many of these technologies are still in development or testing phases, and their full operational capabilities and potential applications remain to be seen.