Defence Technology and Missiles Notes for UPSC

Defence technology is a favourite area of the UPSC Civil Services Examination because it joins science, security and current affairs. Prelims asks about missiles, their range, the organisations that make them and new platforms such as aircraft carriers, submarines and fighter jets. Mains asks about self-reliance in defence (Atmanirbharta), defence exports and modern threats such as cyber war and drones. This note explains the main missiles, systems and policies in simple language, with tables for quick revision.

DRDO and the Defence Ecosystem

The Defence Research and Development Organisation (DRDO), set up in 1958 and headquartered in New Delhi, is the main agency for defence research. It works under the Ministry of Defence and has many laboratories across the country. Other important bodies are Hindustan Aeronautics Limited (HAL), which makes aircraft such as Tejas and helicopters; Bharat Electronics Limited (BEL), which makes radars and electronics; Mazagon Dock and Cochin Shipyard, which build warships; and the Ordnance Factory Board, which was converted in 2021 into seven defence public sector companies. The late Dr. A. P. J. Abdul Kalam led the Integrated Guided Missile Development Programme (IGMDP) in 1983, which gave India its first set of missiles and earned him the title "Missile Man of India".

Classification of Missiles

A missile is a guided weapon. By launch and target, it can be surface-to-surface, surface-to-air, air-to-air, air-to-surface or anti-tank. By range, short-range missiles travel up to about 1,000 km, medium-range 1,000 to 3,000 km, intermediate-range 3,000 to 5,500 km and intercontinental ballistic missiles (ICBMs) more than 5,500 km. By speed, subsonic missiles are slower than sound, supersonic missiles are faster than sound (Mach 1 to 5), and hypersonic missiles travel at more than five times the speed of sound. By path, a ballistic missile is powered at first and then follows a curved path to its target under gravity, while a cruise missile flies low and powered all the way, like a small aircraft.

Important Indian Missiles

India is a member of the Missile Technology Control Regime (MTCR) since 2016, which controls the spread of missile technology. In 2024, India also tested a long-range hypersonic missile, adding to its efforts in this field.

Air Defence and Missile Defence

India has the Ballistic Missile Defence (BMD) programme with two layers: the Prithvi Air Defence (PAD) for high altitude and the Advanced Air Defence (AAD) for low altitude interception. It has also bought the S-400 Triumf long-range system from Russia. The Integrated Air Defence Weapon System and Mission Sudarshan Chakra aim to create a national shield. In May 2025, the Indian forces used a mix of such systems and drones during Operation Sindoor, which showed their importance in modern conflicts.

Aircraft, Ships and Submarines

The Tejas Light Combat Aircraft, built by HAL, is India's indigenous fighter, and the improved Tejas Mk1A and the fifth-generation Advanced Medium Combat Aircraft (AMCA) are in development. The Indian Air Force also operates the Rafale (bought from France), Sukhoi-30MKI and the Apache and Chinook helicopters. The Navy's INS Vikrant, commissioned in 2022, is India's first indigenous aircraft carrier, built at Cochin Shipyard, while INS Vikramaditya is a second carrier. India operates nuclear-powered submarines such as INS Arihant and INS Arighaat, which carry nuclear missiles, completing the sea leg of its nuclear triad. The nuclear triad means the ability to launch nuclear weapons from land, air and sea, which supports India's policy of "No First Use" and credible minimum deterrence.

Self-Reliance Policy: Atmanirbhar Bharat in Defence

India was once the world's largest importer of arms. To change this, the government introduced a series of steps: the Defence Acquisition Procedure gives priority to "Buy (Indian-IDDM)" category; the FDI limit in defence was raised to 74 percent through the automatic route; positive indigenisation lists ban the import of hundreds of items; the Defence Industrial Corridors in Uttar Pradesh and Tamil Nadu support production; the iDEX (Innovations for Defence Excellence) scheme supports start-ups; and a Defence Testing Infrastructure scheme is being built. India's defence exports have grown to more than 20,000 crore rupees a year, with items such as BrahMos missiles, Akash systems and artillery sent to friendly countries.

Emerging Areas: Drones, Cyber and Space

Modern wars are fought with drones, cyber attacks, electronic warfare and satellites. India has set up the Defence Cyber Agency, the Defence Space Agency and the Defence AI Council. Directed energy weapons, such as laser systems tested by DRDO, aim to destroy drones. In 2019, India demonstrated an anti-satellite weapon in Mission Shakti, becoming the fourth country with this ability. The government also created the post of Chief of Defence Staff (CDS) in 2019 to improve coordination among the three services, and theatre commands are being planned.

Challenges and Way Forward

Challenges are delays in projects, dependence on imported engines and key parts, a small private role, a large pension bill that leaves less money for modernisation and the need to match fast-changing threats from the neighbours. The way forward includes more funding for research, closer links among DRDO, private firms, start-ups and universities, faster procurement, stronger testing facilities, skilled manpower and carefully chosen foreign partnerships that give technology transfer and not just purchases. A balanced answer will highlight that strong defence supports economic growth and diplomatic strength too.

India's Nuclear Doctrine

India conducted its first nuclear test, Smiling Buddha, in 1974 at Pokhran, and a series of tests, Operation Shakti, in May 1998. After these, India declared a voluntary moratorium on further testing. Its nuclear doctrine, released in 2003, rests on four ideas. First, India will build and maintain a credible minimum deterrent. Second, it follows a policy of No First Use, which means nuclear weapons will not be used first, but only in retaliation against a nuclear attack on Indian territory or on Indian forces anywhere. Third, the retaliation will be massive and designed to inflict unacceptable damage. Fourth, India will not use nuclear weapons against states that do not have them. Command and control is with the Nuclear Command Authority, headed by the Prime Minister, along with the Strategic Forces Command to manage the weapons. Remember that India is not a signatory of the NPT or CTBT, and has joined export-control groups such as the MTCR, the Wassenaar Arrangement and the Australia Group, but not yet the Nuclear Suppliers Group.

How Defence Technology Helps Civilian Life

Many defence projects have helpful side effects for citizens. Satellite navigation and remote sensing developed for security also support farming and transport. Light-weight materials, radar technology, advanced sensors and drones first built for the military are used in health, disaster relief and logistics. DRDO has developed low-cost artificial limbs, bullet-proof jackets, water purification kits, oxygen systems and the COVID-19 drug 2-DG. This dual-use nature of technology is a good point to add in an answer on why defence research deserves long-term funding. At the same time, remember that the main aim is national security and the protection of citizens from external threats.

Study Tip for Defence Topics

Do not try to memorise every number. Instead, make one page with three columns: the name of the weapon, the category and the single most important fact. For example, write Agni as a ballistic missile that is nuclear-capable, BrahMos as a supersonic cruise missile built with Russia, and Akash as a surface-to-air missile for air defence. Then add the name of the maker, such as DRDO, HAL or BEL. Review this page every week and update it from newspaper reports on tests and exercises. This light method gives you strong recall for Prelims and enough examples for Mains answers without wasting time.

Quick Revision

• DRDO: 1958; IGMDP led by Dr. Kalam from 1983; MTCR member since 2016.
• Agni: ballistic, nuclear-capable. BrahMos: supersonic cruise missile, India-Russia.
• INS Vikrant: first indigenous aircraft carrier (2022). INS Arihant: nuclear submarine.
• Policy: No First Use, positive indigenisation lists, iDEX, 74 percent FDI.

Defence topics need clear tables and simple logic. Memorise each missile with its type, range class and unique fact, link platforms to the organisation that builds them, and add the current news on exports and exercises, and you will do very well on this part of the syllabus.

Related Notes to Read Next

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Frequently Asked Questions (FAQ)

What is DRDO?

The Defence Research and Development Organisation is the main research agency of the Ministry of Defence, set up in 1958, which develops weapons and military technology for India.

Who is called the Missile Man of India?

Dr. A. P. J. Abdul Kalam is called the Missile Man of India for leading India’s missile development programme.

What is the IGMDP?

The Integrated Guided Missile Development Programme was launched in 1983 to develop missiles such as Prithvi, Agni, Akash, Trishul and Nag.

What is the difference between ballistic and cruise missiles?

A ballistic missile is powered at the start and then follows a curved path under gravity, while a cruise missile flies at low altitude with power throughout its flight.

What is BrahMos?

BrahMos is a supersonic cruise missile developed jointly by India and Russia, which can be launched from land, sea, air and submarines.

What is a hypersonic missile?

A hypersonic missile travels at more than five times the speed of sound (Mach 5), which makes it very difficult to intercept.

What is the Agni missile series?

The Agni series is a family of nuclear-capable surface-to-surface ballistic missiles of India, with ranges from about 700 km to over 5,000 km.

What is the nuclear triad?

It is the capability to launch nuclear weapons from land, air and sea. India completed its triad with nuclear submarines like INS Arihant.

What is INS Vikrant?

INS Vikrant is India’s first indigenously built aircraft carrier, built at Cochin Shipyard and commissioned in 2022.

What is iDEX?

Innovations for Defence Excellence is a scheme that supports start-ups and innovators to develop new technologies for the Indian armed forces.

What is the Missile Technology Control Regime?

MTCR is a group of countries that controls the export of missile and unmanned delivery technology. India became a member in 2016.

What is Mission Shakti?

Mission Shakti was a 2019 test in which India shot down a satellite in low Earth orbit, showing its anti-satellite capability.