Lasers have traditionally been used in combat for secondary roles like range calculation, target designation, and weapon guidance. Law enforcement agencies have been using lasers as non-lethal weapons (NLW) for blinding target vision and optical sensors. But now High Energy Lasers (HELs) are slowly entering into the kinetic dimension of warfare as Directed Energy Weapons (DEWs). In the naval domain, HELs, once technologically mature, offer vast applications.
Traditional systems, such as missiles, have flight times that can range from seconds to minutes, whereas lasers provide near-instantaneous engagement. Similarly, lasers have no radar or acoustic signature, and a majority cannot be seen with the naked eye. These attributes make lasers less prone to enemy detection, thus enhancing the stealth advantage and survivability of laser-equipped platforms. With HELs’ accuracy, the enemy’s sensitive equipment, like sensors and targeting systems, can be disrupted to degrade the adversary’s situational awareness and target acquisition capability. Plus, in a complex combat environment where friendly forces are also present in proximity, the risk of collateral damage can be mitigated. As long as a power source is operational, lasers can continue to work without the need for resupply which also simplifies mission planning. Lasers also have a low cost-per-shot ratio when compared with traditional munitions. These characteristics are beneficial in countering artillery barrages, saturated missile strikes and drone swarm attacks.
With the proliferation of new types of threats like drone swarms, loitering munitions, kamikaze drone boats, and hypersonic missiles, the idea for HELs as an integral part of the future layered and multi-domain defensive system is gaining popularity within military circles. According to a RAND study about Air Base Defense, lasers with energy yield in the range of 15kW-50kW can take out mortars, rockets, and small drones. 300kW lasers are generally believed to be the least requirement for intercepting cruise missiles. The United States is currently developing 300kW, 500kW, and 1000kW lasers. Such powerful lasers can destroy high-end threats like missiles and aircraft from longer ranges. Besides aerial and land-based systems, HELs are actively being tested for naval applications. United States, China, the United Kingdom, Germany, and France have successfully tested shipborne HELs, stepping them closer to operational deployment.
As technology progresses, laser systems will become more scalable and modular, facilitating integration into different naval platforms.
United States Navy (USN) has been testing Laser Weapon Systems (LaWS) for the past decade. AN/SEQ-03 LaWS was first installed on USS Ponce – an Austin class amphibious warship – for field testing. AN/SEQ-03 utilises a solid-state laser array, which can be switched to high output to destroy the target with extreme heat or low work to cripple the sensors of the target. This system was devised against low-end asymmetric threats. Similarly, lasers like ODIN (Optical, Dazzling, Interdictor, Navy) have been deployed on USS Dewey – an Arleigh Burke-class destroyer. Unlike AN/SEQ-03, ODIN functions as a dazzler and blinds the enemy’s optical sensors instead of destroying them through physical damage. HELIOS (High Energy Laser with Integrated Optical–dazzler and Surveillance) is the most recent attempt by USN to employ ship-based multi-mission laser technology. Mounted on USS Preble – an Alreign Burke-class destroyer – HELIOS will eventually act as a key element of layered air-defence architecture.
Besides the United States, European navies are also experimenting with ship-based DEWs. Britain’s Dragon-Fire Laser Directed Energy Weapon (LDEW) has been successfully tested to demonstrate its tracking and engaging capability as a stand-alone system against aerial and surface threats. German Navy’s Sachsen class frigate has also successfully test-fired ship-borne laser weapon systems to engage drones at short and very short ranges. Recently, the French Navy successfully tested HELMA-P anti-drone laser weapon from the Horizon class destroyer.
China revealed a prototype of a homegrown naval laser system in 2019 and has been using low-powered lasers ever since. Recently, Chinese military scientists have claimed to develop a new cooling system that eliminates the build-up of laser’s waste heat, thus extending the engagement time, range and damage of laser weapons.
In practice, HELs are not yet combat-proven and have their own technical and operational challenges. In general, four such challenges can be highlighted. First, HELs demand a huge power supply to generate and sustain the required beam intensity. For sustained power supply of lasers, large, complex, and heavy-duty power generators and cooling systems are needed. But naval vessels have restricted space and load-carrying capacity. This suggests that with the current level of technology, integration of HELs on low-medium tonnage vessels is simply impractical.
Second, while lasers offer potential cost savings over traditional systems in terms of ammunition, the initial investment in research and development (R&D) of high-energy laser technology is very expensive. When combined with the system’s life cycle cost involving deployment, maintenance, and logistics of laser systems, the net cost gets substantially higher than traditional systems.
Third, laser efficiency is highly dependent on atmospheric conditions. Adverse environmental effects like thick clouds, heavy rainfall, smog, or even smoke can cause scattering or absorption of laser beams, thus degrading their performance. Even during clear weather conditions, lasers suffer from dispersion at long ranges. The effective range of lasers depends on the power of the laser system and the atmospheric conditions at the time of engagement.
And finally, lasers cannot target non-line of sight (NLOS) targets. Similarly, instead of delivering instantaneous damage, lasers take time to heat and burn the target down. Moreover, countermeasures, like the use of reflective or ablative coatings on aerial systems, decoys and smoke screens, can undermine the efficiency of lasers.
With advancements in technology, laser weapon systems are gradually becoming more practical than ever before. To overcome limitations associated with lasers as naval weapons, it is necessary to surmount the technological, economic, and operational barriers. Advancements in technology will allow the development of lasers with increased power and range. Efforts are underway to improve the atmospheric performance of lasers by neutralising the adverse weather conditions effects through adaptive optics and atmospheric compensation techniques. Similarly, as technology progresses, laser systems will become more scalable and modular, facilitating integration into different naval platforms. These advancements will contribute to the effectiveness, versatility, and readiness of laser weapons in maritime combat scenarios. Once that happens, laser-based defensive systems will replace all legacy gun or missile-based defensive systems. But considering the contemporary host of limitations associated with lasers, this is still a distant prospect.
