Artist’s rendering of Directed Energy Weapon System

A directed-energy weapon damages or destroys its target using focussed energy

The work of the Defence Research and Development Organisation (DRDO) has often been commended, or criticised, with reference to a handful of notable projects. These are usually the Tejas, the Arjun tank and missiles like the Agni series. Less well-known has been the DRDO's work on cutting-edge technologies and weapons, which are yet to enter widespread operational service worldwide.

One such area is the field of 'Directed-Energy Weapons' (DEW). In layman's parlance, a directed-energy weapon damages or destroys its target using focussed energy by means of lasers, microwaves or particle beams.

According to the US think tank, Lexington Institute, "Directed-energy weapons have several advantages over conventional munitions. First, they transmit lethal force at the speed of light (about 300,000 kilometres per second). Second, their beams are not affected by the constraining effects of gravity or atmospheric drag. Third, they are extremely precise. Fourth, their effects can be tailored by varying the type and intensity of energy delivered against targets."

Directed-energy weapons are already in service in the role of 'drone defence' systems. In such systems, laser beams are used to knock out parts of drones, which are becoming an integral part of the military arsenal of most nations. However, their potential extends far beyond to being able to both destroy enemy targets and defend vital infrastructure from air and missile attack.

Earlier this week, US defence website Defence News reviewed the status of hypersonic weapons and DEW programs worldwide. Defence News reported the DRDO has sought $100 million from the ministry of defence to develop a high-power laser weapon.

"The classified project, dubbed DURGA-II (Directionally Unrestricted Ray-Gun Array), will see the Indian Army receive the 100-kilowatt, lightweight directed-energy system, a service official told Defence News. A senior DRDO scientist said on condition of anonymity that the DURGA-II program is currently in the concept stage. He added that the organization is developing and improving various laser-generation techniques using solid state, fibre and chemical lasers for defensive and offensive use.

The scientist also said DURGA-II is to be integrated with land-, sea- and air-based platforms," Defence News reported.

The Defence News report noted the Laser Science and Technology Centre at Delhi was the lead laboratory in developing laser weapons. "The centre has so far made a 25-kilowatt laser that can target a ballistic missile during its terminal phase at a maximum distance of 5 kilometres," Defence News reported.

Interestingly, the existence of a DURGA project has been reported for around two decades now, dating back to the early 2000s. A study by Indian Air Force officer K.K. Nair published by the United Service Institution of India (USI) in 2008 referred to the Directionally Unrestricted Ray-Gun Array (DURGA), and noted there was little progress in the project.

In 2017, DRDO tested a 1KW laser weapon mounted on a truck at a test facility in Chitradurga, the laser hit a target 250m away. The laser test was conducted in the presence of then defence minister Arun Jaitley.

Tough To Develop

High-power laser weapons are difficult to develop, a notable problem being provision of adequate power to the system. The Economic Times highlighted challenges including “developing a cooling mechanism for the system that heats up when the laser beam is fired, ensuring a focused beam towards a distant target and optoelectronics, or optronic, involving lenses to create that focus..."

HELIOS

In January, US aerospace giant Lockheed Martin delivered the first unit of its High Energy Laser with Integrated Optical-dazzler and Surveillance (HELIOS) laser system to the US Navy. The HELIOS has power in excess of 60KW and is used primarily to damage smaller surface ships and drones. However, according to reports, upgrades to HELIOS with increased power would enable the system to target anti-ship missiles fired at ships.