The idea that lasers might become a real thing was first imagined in the early 1900s, but experimentation into basic lasers only really started in the 1950s. This experimentation did deliver the first low-power laser prototypes in 1960, but it would take decades of incremental improvements before lasers with military potential first saw the light.
Research to create military-grade lasers attracted little attention until U.S. President Ronald Reagan launched the Strategic Defense Initiative in 1983. Dubbed “Star Wars,” the initiative called on scientists to develop satellite-based lasers that could disable Soviet nuclear ballistic missiles before they could re-enter Earth’s atmosphere.
That program was eventually deemed impractical, but the research done for it saw some use in probably the most powerful laser created during the 1990s, the YAL 1A, a chemical laser so large that it filled the whole interior of the massive Boeing 747 that it was designed to be deployed on. With development starting in 1996, this huge airplane-laser combination first started flying in 2002, and the completed system was delivered in January 2006. The first firing of the complete laser system during flight happened in 2009. In February 2010, the system successfully destroyed a liquid-fueled ballistic missile. The huge airborne laser was supposed to patrol the skies near enemy airspace and strike at U.S.-bound nuclear missiles as they launched toward space.
However, the system was considered to be too big, too expensive, too complex to maintain, and risked an environmental catastrophe because it required flying with large volumes of toxic chemicals at altitudes higher than 40,000 feet. In December 2011, after 16 years and $5 billion in development costs, it was announced that the project would be canceled. The YAL 1A prototype made its last flight to its final resting place in February 2012.
The fate of the YAL 1A illustrated the fundamental historical problems with high-power lasers: They have always been too big to fit into mobile platforms, they required a lot of electrical energy to create focused light energy, and they created a lot of heat that could fry their own components and the components of the platforms that carried them.
However, a lot of these problems were already being solved as the aging technology of the massive YAL 1A chemical laser was being squeezed into its Boeing 747.
According to Rob Afzal, a senior laser scientist at Lockheed Martin, laser development reached a dead end in the 1980s because of a lack of scalable components. He told The Warzone in December 2020 that this problem was partly solved in the early 1990s when “billions and billions of dollars started to pour into the development of fiber-optic communications equipment — how to make the optical fiber, how to pull kilometers and kilometers of it with high purity, how to make high-speed electronics to be able to do communications, semiconductor diode lasers to send the data down the fibers.”
Afzal explained that the subsequent development of “fiber laser technology” allowed industries to develop lasers that were very efficient at converting electrical power to optical power. “The beam quality that came out of the fiber laser, meaning the ability for that beam to be focusable, to provide a high-intensity spot to do things like melt metal and drill holes, the beam quality was very high,” he added.
Of course, as Afzal explained, “It’s one thing to cut metal that’s centimeters away, it’s another thing to take out a mortar at two kilometers.” So, the next innovation that changed the game in the last decade was to figure out “how to scale fiber lasers to weapons-class power.” He added that, “The way that’s done is, instead of just building a single laser at 50 kilowatts or 100 kilowatts or something like that, we are actually taking individual fiber lasers and combining the outputs of the beams into a single high-power beam, and we do that using a technique we call Spectral Beam Combination.”
The result of these innovations is that companies like Lockheed Martin and Raytheon are currently producing relatively small laser systems that can fit on pickup trucks and Stryker infantry vehicles. Raytheon, for instance, is currently field-testing a 50-kilowatt system that fits inside a Stryker and can destroy incoming aerial drones and mortars. It is also field-testing a smaller 15-kilowatt laser that fits on a lightweight Polaris MRZR — a military grade dune buggy — giving U.S. special-operations forces the ability to destroy small to medium drones in their surrounding airspace. These systems rely on targeting subsystems that employ radars, robotics and high-quality electro-optical/infra-red (EO/IR) sensors to detect and instantly track even very small objects like mortars, rockets and small FPV drones.
The crew of a Stryker fitted with such a laser-plus-robotics-plus-sensor system simply has to make sure the system is switched on. Michael Hofle, Raytheon’s product lead for its high-energy lasers, told Task & Purpose that if a mortar or drone enters the Stryker’s airspace, the system’s radar will immediately give an audible warning and the laser’s beam director pod will immediately turn to the spot where the radar directed it. The director pod will then employ its EO/IR sensors to track the object while showing the sensor’s video feed of the object to the crew. Once the crew makes the decision to fire, the system automatically fires its laser while keeping the beam focused on the moving target. The crew also has the option to select the exact position on the drone where it wants the laser to focus its energy. Typically, a drone or mortar kill would require a few seconds of lasering.
Hofle explained that one of the most impressive aspects of these small lasers is that they can track the target so precisely, and direct their beams so exactly, that they can keep all the light energy focused on a spot as small as a dollar coin over kilometers of airspace. The crew even has the option to click on the exact part of the target object that it wants the laser focus on. So, it’s not just the advances in fiber-laser technology that enables these lasers to be fitted into small form factors, it’s also the advances in robotics and optical tracking systems.
An unexpected bonus of these vehicle-borne air-defense lasers is that they give their operators access to the high-quality night vision imaging of their EO/IR systems. This comes in handy when the vehicle is part of an expeditionary group in hostile environments, requiring it to use night vision and electro-optical imaging to scan for possible threats like enemy ground-unit assaults.
The primary value of laser systems is that they allow the defender to destroy small, cheap drones without having to use expensive anti-air missiles or expensive programmable ammunition. Once acquired, a mobile or fixed laser system can destroy a large number of cheap drones for only a few dollars worth of gasoline and maintenance. This is a big win, as air-defense missiles like the Patriot PAC-3 typically cost $4 million per missile. Even a small shoulder-fired air-defense missile like the Stinger sells for anything between $100,000 and $400,000, depending on who you ask.
Hofle said that Raytheon’s truck-borne laser can fire an average of 30 bursts in quick succession before its battery needs to recharged by its generator, a process that it says takes around 20 to 30 minutes. This means that a laser system can destroy large numbers of drones and mortars without needing to expend expensive ammunition, without needing ammo to be carted to it, and without the risk of ammo exploding next to it or while in transit to it. Unlike in sci-fi movies, the beams fired by these lasers are also invisible and quiet, which makes it hard for the enemy to detect where the system is located.
As it prepares for a possible invasion of Taiwan, China has invested heavily in all sizes of drones — from very small quadcopters to large winged drones and even rocket-powered supersonic drones. Both Chinese and Taiwanese military analysts have recently stated that China is likely to rely heavily on its large arsenal of drones during any hypothetical invasion of Taiwan. The Ukraine conflict has shown how deadly even a small quadcopter drone can be, even if it only has one video camera with which it can send back targeting data to distant artillery units. Such cheap FPV drones — some cost as little as $200 or less — are also regularly used to drop small mortars directly onto ammunition stockpiles and onto troops in trenches.
These small drones are not just dangerous and cheap, they are also very hard to spot. By deploying small laser systems paired with detection radars on trucks or fighting vehicles, Taiwan’s military would be able to quickly detect these almost-invisible infiltrators and zap them before they can cause damage.
As modern military strategy is leaning more and more toward the use of swarms of kamikaze drones to attack high-value targets, it is becoming increasingly clear that Taiwan needs to find inexpensive ways to destroy swarms of these inexpensive drones. Currently, one of the most inexpensive ways to stop such drone swarms is to use one mobile or fixed laser system to take out each drone in the swarm one by one, as quickly as possible. However, given the fact that current truck-borne laser systems require a few seconds to track and “fry” a single drone, it would seem that a single laser system might not have the power required to kill enough kamikaze drones quickly enough, if they attack as a swarm. Such cases would require multiple laser systems working together.
To counter drone swarms, another option would be to use another type of “directed energy weapon” that directs high-powered microwaves (HPM) at the swarm, rather than the directed light energy of a laser beam. Whereas lasers heat and burn drones from the outside, the electromagnetic radiation from HPM weapons pass through plastic and fiberglass and react with metals inside the electronics of the drones, thereby frying them from the inside. Such HPM weapons also create a much wider beam than a laser can and have proven to be relatively effective against drone swarms. A more expensive way to take out a drone swarm is with a “smart” autocannon like the Oerlikon Skyranger 35 that programs its programmable ammunition to explode in front of the swarm, thereby creating a cloud of fast-moving shrapnel that tears through the swarm.
The U.S. Government Accountability Office reported in April that the Department of Defense is currently developing three advanced high-energy laser (HEL) types, saying that the “DOD and each of the military departments are working toward building lasers with output in the 300-, 500-, and 1,000 kilowatt power ranges. Such systems could eventually enable HEL to engage powerful targets such as cruise missiles.” The office added that “DOD officials said they expect the laser scaling initiative to result in an HEL prototype in the 300 kilowatt class delivered in fiscal year 2023.”