Combat lasers: From sci‑fi to real-world battlefield tech

The laser itself, an acronym for Light Amplification by Stimulated Emission of Radiation, is a subset of so-called directed energy weapons. It is, in a sense, a type of lamp that emits electromagnetic radiation in various ranges through the phenomenon of stimulated emission. Laser radiation is coherent, and the beam is characterized by low divergence.

Lasers have been used militarily for decades—initially, they were mainly employed as key elements in weapon guidance systems. They continue to serve this function today, as seen in the Polish Pirat/APR-120/155 system. Additionally, laser rangefinders are standard components of fire control systems.

There are also lasers designed to injure rather than kill targets. Their primary role is to permanently blind opponents. However, such lasers are banned as inhumane under Protocol IV of the Convention on Certain Conventional Weapons from 1980. A slight exception exists for lasers that cause temporary blindness, which law enforcement may use. These lasers typically have a power output well below one kilowatt (kW).

Decidedly more powerful are true combat systems, which remain largely in advanced experimental stages but show promising results. Currently, tested combat lasers generally have power outputs ranging from tens of kW (usually 20-60 kW), with some significantly more powerful systems reaching hundreds of kW. The main goal of developing such "cannons" is to provide the future user with a cost-effective defensive system.

Lasers are often considered potential successors to small-caliber cannons and large-caliber machine guns for defensive applications. However, this requires delivering energy to the target at a rate of 4 kW per square inch of its surface, enabling the laser to burn through the object, damaging or even destroying it.

As for the targets themselves, they generally include all sorts of drones, missile and cruise missile targets, small boats (including unmanned "surface torpedoes"), and similar objects. The proliferation of inexpensive, improvised combat drones (simple FPV drones), despite their low individual effectiveness, is driving the development of laser air-defense systems due to cost-effectiveness.

The cheapest, albeit least effective, suicide drone costs around $1,000. In comparison, the cost of a single 1.2-inch programmable shell is similar, while that of a rocket projectile is many times higher. This has created a need for a more affordable alternative, and it seems that lasers might be the answer to this problem. Various estimates suggest that a single "shot" costs a few to a dozen dollars, generally offering adequate performance in range and accuracy.

Research on combat lasers is being conducted in many countries, often via multiple avenues. Leading the efforts is the USA, which developed the YAL-1 system—a type of oxygen-iodine laser cannon mounted on the nose of a Boeing 747-400F aircraft. The first trials of a similar system were conducted in the 1980s, targeting ballistic missiles. However, it never entered mass production, and the program was abandoned several years ago, although the concept persisted for some time.

A similar project, this time as an anti-satellite weapon, was attempted by Russia under the Sokół-Echelon program. Smaller lasers, according to some concepts, could form a defensive system for sixth-generation multi-role aircraft (e.g., American NGAD), serving as weapons to destroy anti-aircraft and air-to-air missiles.

In naval fleets, there is also a trend towards deploying laser weapons. The US Navy tested a laser "cannon" aboard the USS Ponce and later the USS Portland, which successfully shot down an RQ-21 Blackjack drone during tests using the SSL-TM laser. Europe is not far behind. In 2022, the German frigate Sachsen shot down multiple drones using the LWD device developed by MBDA Deutschland and Rheinmetall Waffe Munition.

LWD performed over 100 test launches from the Sachsen frigate, proving that the laser can effectively combat targets in a maritime environment. Meanwhile, the British are intensively testing the DragonFire system, which has a power output of up to 50 kW and is intended for deployment on various Royal Navy surface ships (including Type 32 frigates). The Chinese are also working on a similar system.

Developing an effective land-based laser has proven to be most challenging, as the Americans have recently realized. During May tests of the DE M-SHORAD laser air-defense system on a Stryker transporter chassis, it was found that the 50 kW system did not meet expectations in terms of effectiveness at longer distances (up to 6 miles) and was unreliable during on-the-move engagements.

Nevertheless, the US Army is funding several laser weapon programs with power outputs ranging from 10-300 kW for various applications: portable, stationary, and mobile. The most interesting land-based laser system remains the Soviet 1K17 Shatie on the 2S19 howitzer chassis, which was intended to destroy the optoelectronic equipment of enemy vehicles. Its effectiveness is not well-documented, but it was expensive to produce—one unit required about 66 pounds of synthetic rubies.

Beijing has advanced further, producing the fiber laser Silent Hunter, which is effective up to 0.6 miles and was used in combat by Saudi Arabia. It is possible that the Israeli fiber-optic Iron Beam was also used in combat during clashes in the Gaza Strip. Another interesting solution is the American Zeus-HLONS, a lightweight system with a power output of about 10 kW, mounted on the roof of an HMMWV vehicle. It serves to destroy mines and improvised explosive devices, with a range of up to 1,000 feet and the capability to fire up to 2,000 times a day.

The lasers mentioned are just selected examples of contemporary (and not only) laser weapons. They differ by country of origin, manufacturer, operational mode, and intended use, but they all share certain limitations. The laser beam is susceptible to "blooming" (beam spread and thus reduced power impacting the target), especially when the air contains impurities such as smog, dust, or dense fog. Consequently, smoke grenade launchers are used on combat vehicles to hinder laser use (usually limited to rangefinders).

Furthermore, the development of laser weapons as a defensive "shield" against missiles and drones ("sword") has led to the creation of a "counter-shield": work on coatings for missiles, drones, or aircraft that can limit the effectiveness of such systems. Lasers, especially higher-powered ones, require significant electrical energy, which must be produced, stored, and then transferred to the "cannon." This entire process generates cooling challenges. Despite these problems, the economic considerations point towards the continued development of laser combat systems. However, it remains uncertain when they will be fully incorporated into military use.