Directed Energy Weapons (DEWs) and Hypersonic Missiles | Science & Technology for UPSC CSE PDF Download

Introduction

Directed Energy Weapons (DEWs) and hypersonic missiles are cutting-edge defence technologies transforming modern warfare. DEWs use focused energy, such as lasers or microwaves, to disable or destroy targets at the speed of light, offering precision and cost-effectiveness. Hypersonic missiles, traveling faster than five times the speed of sound (Mach 5), provide unmatched speed and manoeuvrability for strategic strikes. As of August 2025, these technologies are central to global arms races, with major powers like the US, China, and Russia advancing rapidly. For India, they are critical for addressing regional threats from China and Pakistan, aligning with the Atmanirbhar Bharat initiative for self-reliant defence. 

Fundamentals of Directed Energy Weapons (DEWs)

Directed Energy Weapons convert electrical or chemical energy into focused beams to engage targets. They operate at the speed of light, enabling instantaneous strikes with minimal collateral damage compared to traditional kinetic weapons.

• Core Principles: DEWs deliver energy in the form of electromagnetic radiation (lasers, microwaves) or particle beams. Their effectiveness depends on power output (measured in kilowatts or megawatts), beam quality, and the ability to propagate through the atmosphere. The energy causes thermal damage (burning or melting), mechanical disruption (shockwaves), or electronic interference (disabling circuits).
• Advantages:
  • Unlimited "magazine" as long as power is available, unlike finite ammunition.
  • Low cost per shot, ranging from $1 to $10, compared to millions for missiles.
  • Scalable effects, from non-lethal (e.g., dazzling sensors) to destructive (e.g., melting drones).
• Limitations:
  • Atmospheric interference (e.g., fog, dust, rain) reduces beam effectiveness.
  • High energy demands require advanced power sources and cooling systems.
  • Limited range for high-power systems due to beam divergence.

Types of DEWs

DEWs encompass various technologies, each suited for specific defence roles:

• High-Energy Lasers (HELs): Use coherent light to burn or melt targets. Types include solid-state lasers (compact, fibre-based) and chemical lasers (high power but bulky). Example: The US Navy’s HELIOS (60 kW) successfully targeted cruise missiles in 2024 tests.
• High-Power Microwaves (HPMs): Emit radio-frequency pulses to disrupt electronics, ideal for countering drones or missile guidance systems. China’s compact HPM gun, tested in 2025, achieved over 10,000 shots without failure.
• Particle Beam Weapons: Accelerate charged particles (e.g., protons) for kinetic impact. These remain experimental due to challenges in maintaining beam stability.
• Millimeter Wave Weapons: Cause surface heating for non-lethal applications, such as crowd control. Example: The US Active Denial System uses 95 GHz waves to repel targets.

Applications of DEWs in Defence

DEWs are versatile, addressing diverse threats in modern warfare:

• Counter-Air and Missile Defence: Neutralize drones, cruise missiles, and rockets. The US Army’s Directed Energy Manoeuvre Short-Range Air Defence (DE M-SHORAD, 50 kW) successfully countered drone swarms in 2025 trials.
• Ground and Naval Warfare: Protect military bases and ships from asymmetric threats like small boats or mortars. The UK’s DragonFire (50 kW) is slated for anti-drone and anti-mortar roles by 2027.
• Space and Electronic Warfare: Disable satellite electronics or communications via HPMs, with potential for biosecurity risks if misused (e.g., targeting critical infrastructure).
• Non-Lethal Applications: Deter crowds or disable vehicles without permanent harm, useful in peacekeeping or border security.

Global Developments in DEWs

Major powers are investing heavily in DEWs to gain strategic advantages:

• United States: Leads with multiple programs. The Navy’s HELIOS (60 kW) targets missiles, while the Army’s DE M-SHORAD counters drones. The Air Force’s THOR (HPM system) disables drone swarms. The US allocated over $1.2 billion in FY2025 for DEW scaling and deployment.
• China: Developed a compact HPM gun in 2025 for anti-drone and anti-missile roles. China also tested a laser-based railgun, showcasing integration with other advanced systems.
• Russia: Deploys the Peresvet laser for satellite blinding and air defence, though its operational use remains limited.
• Europe and Israel: The UK’s DragonFire (50 kW) aims for operational use by 2027. Israel’s Iron Beam (100 kW) is set for deployment in 2025 to counter rockets and mortars.
• Other Players: France and Japan are developing tactical laser systems for naval and air defence.

India’s Initiatives in DEWs

India is advancing DEW capabilities through the Defence Research and Development Organisation (DRDO) and private sector collaboration:

• Key Projects:
  • KALI (Kilo Ampere Linear Injector): An HPM system generating high-energy pulses for electronic disruption.
  • DURGA (Directionally Unrestricted Ray-Gun Array): A laser-based system targeting drones and missiles. DRDO tested a 10 kW DEW in 2024, with plans for a 100 kW system by 2027.
  • Sudarshan Chakra: A 2025 anti-drone DEW, integrated with India’s S-400 air defence system for layered protection.
• Developments in 2025: Successful trials of low-power lasers against small drones; integration with electronic warfare suites by Bharat Electronics Limited (BEL).
• Strategic Role: Counter China’s HQ-19 missile defence system and Pakistan’s drone incursions along borders. Enhances maritime security in the Indian Ocean Region.
• Challenges:
  • Limited power generation and thermal management technologies.
  • Funding constraints, with approximately ₹15,000 crore allocated for DEW R&D.
  • Need for skilled workforce and private sector scaling.

Challenges and Ethical Issues in DEWs

• Technical Challenges:
  • Beam divergence reduces effectiveness over long ranges.
  • High power requirements demand compact, reliable energy sources.
  • Weather dependency limits operational reliability.
• Ethical Concerns:
  • Potential for indiscriminate harm, raising questions under the Geneva Conventions.
  • Autonomous DEWs risk unintended escalations, necessitating human-in-the-loop protocols.
  • Dual-use potential (e.g., bioterrorism via HPMs targeting infrastructure) requires stringent controls.
• Regulatory Gaps: No specific international treaties govern DEWs, though calls for bans on fully autonomous systems are growing.

Fundamentals of Hypersonic Missiles

Hypersonic missiles travel faster than Mach 5 (approximately 6,174 km/h) and are designed for manoeuvrability, making them difficult to intercept.

• Core Principles: Operate in the upper atmosphere with unpredictable trajectories. Two main types: Hypersonic Glide Vehicles (HGVs) boosted by rockets then glide to targets, and Hypersonic Cruise Missiles (HCMs) powered by scramjet engines for sustained flight.
• Advantages:
  • Evade traditional missile defence systems due to speed and manoeuvrability.
  • Enable rapid, precise strikes on time-sensitive targets.
  • Enhance deterrence by compressing adversary response times.
• Limitations:
  • Extreme heat (2,000°C+) requires advanced materials like carbon composites.
  • High development and production costs.
  • Guidance challenges in plasma sheaths formed at hypersonic speeds.

Types of Hypersonic Missiles

• Hypersonic Glide Vehicles (HGVs): Launched by ballistic missiles, glide at low altitudes. Examples: China’s DF-17 (Mach 10), Russia’s Avangard (Mach 20+).
• Hypersonic Cruise Missiles (HCMs): Use scramjet engines for sustained flight. Examples: Russia’s Zircon (Mach 9), India’s BrahMos-II (Mach 8 projected).
• Boost-Glide Systems: Combine rocket boost with gliding warheads. Example: US AGM-183 ARRW (Mach 5+).

Applications of Hypersonic Missiles in Defence

• Strategic Strikes: Target high-value assets like aircraft carriers or command centres, supporting anti-access/area denial (A2/AD) strategies.
• Tactical Roles: Neutralize time-critical targets, such as mobile missile launchers.
• Deterrence: Alter nuclear and conventional balance by reducing reaction times, impacting strategic stability.

Global Developments in Hypersonic Missiles

• United States: Tested SM-6 Block IB (2025) for hypersonic capabilities; Hypersonic Air-breathing Weapon Concept (HACM) funded at $517 million in FY2025. Long-Range Hypersonic Weapon (LRHW) faced delays but progressed in 2025 trials.
• China: DF-27 (Mach 10, 5,000 km range) operational since 2019; deployed in Indo-Pacific to counter US forces.
• Russia: Oreshnik (Mach 11) used in Ukraine (2024); Kinzhal (Mach 10) deployed on MiG-31 aircraft.
• Other Players: UK, Australia, and Japan collaborate under AUKUS for hypersonic missiles, with tests planned for 2025.

India’s Initiatives in Hypersonic Missiles

India is emerging as a key player in hypersonic technology, driven by DRDO and private partnerships:

• Key Projects:
  • Long-Range Hypersonic Missile (LR-HM): Tested in 2024 at Mach 6, 1,500 km range.
  • BrahMos-II: A scramjet-powered missile aiming for Mach 8, expected by 2027.
  • ET-LDHCM (Project Vishnu): Mach 8, 1,500 km range, under development for multi-platform launches.
  • Hypersonic Technology Demonstrator Vehicle (HSTDV): Successful scramjet tests in 2024, achieving a world-record sustained flight.
• Developments in 2025: Over 1,000 seconds of scramjet testing; glide vehicle development on track for 2027 induction.
• Strategic Role:
  • Counter China’s DF-17 and HQ-19 systems in the Indo-Pacific.
  • Deter Pakistan with rapid, precise strike capabilities.
  • Enhance maritime strike capabilities against hostile naval assets.
• Challenges:
  • Sustained hypersonic flight requires advanced thermal materials.
  • High costs and complex guidance systems delay full operationalization.
  • Target induction timelines of 2026–2027.

Challenges and Ethical Issues in Hypersonic Missiles

• Technical Challenges:
  • Thermal management for sustained flight at extreme temperatures.
  • Accurate guidance through plasma sheaths disrupting signals.
  • Scaling production for cost-effective deployment.
• Ethical Concerns:
  • Escalation of arms races, destabilizing global security.
  • First-strike capabilities risk miscalculations in nuclear contexts.
  • Lack of international treaties governing hypersonic weapons.
• Defence Needs: India is developing anti-hypersonic interceptors (planned by 2031) to counter adversary systems.

Directed Energy Weapons and hypersonic missiles are reshaping modern warfare, offering India strategic tools to counter regional threats and assert technological prowess. DEWs provide cost-effective, precise defence against drones and missiles, while hypersonic missiles enable rapid, evasive strikes. As of August 2025, India’s advancements, such as the Sudarshan Chakra DEW and LR-HM tests, align with global leaders like the US and China. However, technical challenges, ethical concerns, and the need for robust counter-technologies demand attention.