Defence Technology for UPSC: Ballistic and Cruise Missiles, THAAD, FOBS, Fifth-Generation Fighters, Drone Swarms and Stealth
How UPSC Tests Defence Technology
🎯 Exam priority: Tier-2. Defence technology is a small slice of Science and Technology (4 of 104 questions) but is rising with news. UPSC asked: INS Astradharini (2016); THAAD (2018); what drones can do (2020); the Fractional Orbital Bombardment System (2022); ballistic versus cruise missiles (2023); fifth-generation fighters (2024); UAVs and Indian defence aircraft (2025); and, in 2026, stealth technology, black boxes and drone swarms (provisional key).
Three boxes: missiles (what they are and who has them), aircraft and unmanned systems and detection and defence (radar, stealth, missile defence).
Missiles, Missile Defence and 2025 Tests
Missiles
Type | Features | Exam fact |
Ballistic missile | Rocket-powered at launch, then follows a high arc under gravity; very fast | Agni series (India); intercontinental ballistic missiles reach over 5,500 km. The 2023 question wrongly said ballistic missiles are 'jet-propelled at subsonic speed' |
Cruise missile | Jet-propelled (air-breathing), flies low and level through its flight, guided throughout | BrahMos is a supersonic cruise missile; Agni-V is not a cruise missile (2023: both statements wrong) |
Air-to-air missile | Fired from fighters at aircraft | Astra is a beyond-visual-range air-to-air missile; it was test-fired from an LCA prototype on 12 March 2025 with a direct hit |
Surface-to-air missile and air defence | Akash and its variants engage aircraft and drones | ECIL integrated the first production module of Akash-Prime, capable of 360-degree engagement of multi-directional attacks from aircraft and drones |
FOBS (Fractional Orbital Bombardment System) | A warhead is put in a low orbit and brought down on the target before a full orbit is complete | 'A missile is put into a stable orbit around the Earth and deorbits over a target' (2022); hard to track |
Anti-ballistic missile defence | Intercepts ballistic missiles in flight | THAAD (Terminal High Altitude Area Defense) is an American anti-missile system (2018) |
2025 tests (secondary sources): Agni-5 from Chandipur on 20 August 2025; Pinaka Long Range Guided Rocket (LRGR-120) maiden flight on 29 December 2025 at 120 km range; two Pralay missiles salvo-launched on 31 December 2025. DRDO obtained about ₹1.30 lakh crore of procurement approvals for indigenous systems in 2025, the highest in a year.
Navy: INS Astradharini is a torpedo launch and recovery vessel (2016).
Aircraft, Drones, Stealth and Black Boxes
Aircraft and unmanned systems
Fighter generations: fifth-generation fighters combine stealth shaping, internal weapon bays, supercruise and sensor fusion. The Rafale and Tejas Mk-1 are fourth-generation class and the MiG-29 is also fourth generation, so none of the three in the 2024 question is fifth-generation. India's own fifth-generation project is the AMCA.
UAVs: not every UAV can land vertically, hover automatically or run only on batteries; fixed-wing and fuel-powered drones exist (2025 PYQ: none of the 'all types' statements is correct). Drones can spray pesticides, inspect volcano craters and collect whale breath for DNA analysis (2020 PYQ: all three).
Drone swarms (2026, provisional key): individual drones communicate with each other, and GPS spoofing is a common counter. Swarms do not use the terahertz band to talk to the command centre.
Indian defence aircraft pairs (2025): Dornier-228 is a maritime patrol aircraft and the C-17 Globemaster III a military transport; the IL-76 is also a transport aircraft, not a supersonic combat plane.
Detection and defence
Stealth (2026, provisional key): stealth objects have a very small radar cross-section and are coated with radar-absorbing material; radars on particular frequencies can still detect them. Metamaterials are used to reduce, not increase, scattering.
Black boxes (2026, provisional key): two recorders, one for cockpit voice and one for flight data; they are painted bright orange for visibility and their memory units are protected in stainless steel or titanium. The underwater locator beacon sends acoustic pings (not red light pulses).
Other indigenous systems: the Department of Atomic Energy's ECIL has built a CBRN (chemical, biological, radiological and nuclear) protection system, launcher interface units for the Agni launcher and a weapon control system for the Astra vertical-launch short-range surface-to-air missile tested on a naval ship.
How UPSC Could Ask This Next
Missile classes and examples: ballistic versus cruise, range classes, hypersonic glide vehicles and scramjets.
Platforms: which aircraft or ship is of which type or generation.
Counter-systems: missile defence, counter-drone, electronic warfare.
Indigenisation: DRDO tests and acceptances of necessity.
Further Reading
NCERT Biology (Class 12) and Geography textbooks, the India State of Forest Report, the MoEFCC Annual Report, the Economic Survey and the official lists cited in this note — the primary sources behind every figure above.
Test Yourself: Practice Questions and PYQs
Twelve practice questions on missiles, aircraft, drones, stealth and black boxes, followed by the real UPSC Prelims questions.
Practice Questions
Q1. Ballistic missiles are best described as
(a) rocket-powered missiles that follow a high arc after the boost phase
(b) jet-propelled missiles that fly low throughout
(c) unpowered gliders
(d) guided bombs dropped by aircraft
Show answer
Answer: (a) — Cruise missiles are air-breathing and fly low.
Q2. BrahMos is a
(a) torpedo
(b) beyond-visual-range air-to-air missile
(c) solid-fuelled intercontinental ballistic missile
(d) supersonic cruise missile
Show answer
Answer: (d) — UPSC's 2023 key rejected the reversal of Agni-V and BrahMos.
Q3. Astra is a
(a) beyond-visual-range air-to-air missile
(b) intercontinental ballistic missile
(c) ship-launched torpedo
(d) anti-tank mine
Show answer
Answer: (a) — It was tested from an LCA prototype on 12 March 2025.
Q4. THAAD, sometimes seen in the news, is
(a) an American anti-missile system
(b) an Israeli radar system
(c) a Japan-South Korea collaboration
(d) India's indigenous anti-missile programme
Show answer
Answer: (a) — UPSC's 2018 key.
Q5. A Fractional Orbital Bombardment System
(a) places a probe on a comet
(b) lands a spacecraft on another planet
(c) puts a missile into a stable orbit and de-orbits it over its target
(d) launches a missile to destroy asteroids
Show answer
Answer: (c) — UPSC's 2022 key.
Q6. Which of the following are considered fifth-generation fighter aircraft? 1. Rafale 2. MiG-29 3. Tejas Mk-1. How many of them are?
(a) Only two
(b) None
(c) All three
(d) Only one
Show answer
Answer: (b) — UPSC's 2024 key.
Q7. Stealth technology works mainly by
(a) flying at supersonic speed
(b) making it perfectly invisible to every sensor
(c) giving the object a very small radar cross-section and radar-absorbing coatings
(d) increasing the scattering of radar waves
Show answer
Answer: (c) — Radars on specific frequencies can still detect stealth objects.
Q8. A flight 'black box' consists of
(a) a radar beacon only
(b) a fuel gauge
(c) a single camera
(d) a cockpit voice recorder and a flight data recorder
Show answer
Answer: (d) — Their memory units are protected by stainless steel or titanium.
Q9. Which pair of Indian defence aircraft is correctly matched?
(a) Dornier-228: supersonic fighter
(b) IL-76: supersonic combat aircraft
(c) C-17 Globemaster III: maritime patrol
(d) Dornier-228: maritime patrol aircraft
Show answer
Answer: (d) — UPSC's 2025 key: two of the three given pairs were correct.
Q10. INS Astradharini is
(a) an amphibious warfare ship
(b) a torpedo launch and recovery vessel
(c) an aircraft carrier
(d) a nuclear-powered submarine
Show answer
Answer: (b) — UPSC's 2016 key.
Q11. Which of the following can drones do at the present level of technology?
1. Spray pesticides on a crop field
2. Inspect the craters of active volcanoes
3. Collect breath samples from spouting whales for DNA analysis
(a) 2 and 3 only
(b) 1, 2 and 3
(c) 1 and 3 only
(d) 1 and 2 only
Show answer
Answer: (b) — UPSC's 2020 key.
Q12. The Pinaka Long Range Guided Rocket (LRGR) had its maiden flight in December 2025 at a maximum range of
(a) 1,200 km
(b) 12 km
(c) 20 km
(d) 120 km
Show answer
Answer: (d) — The flight was at Chandipur, Odisha (secondary sources).
UPSC Previous Year Questions (PYQs)
Real UPSC Prelims questions, checked against the official paper and answer key.
Q1. (2016) Which one of the following is the best description of 'INS Astradharini', that was in the news recently?
(a) Nuclear-powered aircraft carrier
(b) Amphibious warfare ship
(c) Torpedo launch and recovery vessel
(d) Nuclear-powered submarine
Show answer
Answer: (c) — INS Astradharini is a torpedo launch and recovery vessel of the Indian Navy.
Q2. (2018) What is “Terminal High Altitude Area Defence (THAAD)”, sometimes seen in the news?
(a) A defence collaboration between Japan and South Korea
(b) An Israeli radar system
(c) An American anti-missile system
(d) India's indigenous anti-missile programme
Show answer
Answer: (c) — THAAD, the Terminal High Altitude Area Defense, is an American anti-ballistic-missile system.
Q3. (2020) Consider the following activities:
1. Spraying pesticides on a crop field
2. Inspecting the craters of active volcanoes
3. Collecting breath samples from spouting whales for DNA analysis At the present level of technology, which of the above activities can be successfully carried out by using drones?
(a) 1, 2 and 3
(b) 2 and 3 only
(c) 1 and 2 only
(d) 1 and 3 only
Show answer
Answer: (a) — Drones can spray pesticides on fields, inspect volcano craters and collect the breath of spouting whales for DNA analysis. All three.
Q4. (2022) Which one of the following statements best reflects the idea behind the “”Fractional Orbital Bombardment System” often talked about in media ?
(a) A missile is put into a stable orbit around the Earth and deorbits over a target on the Earth.
(b) A hypersonic missile is launched into space to counter the asteroid approaching the Earth and explode it in space.
(c) A spacecraft lands on another planet after making several orbital motions.
(d) A spacecraft moves along a comet with the same speed and places a probe on its surface.
Show answer
Answer: (a) — A fractional orbital bombardment system puts a warhead into a low stable orbit and brings it down on its target before a full orbit is complete, which makes the missile hard to track.
Q5. (2023) Consider the following statements:
1. Ballistic missiles are jet-propelled at subsonic speeds throughout their flights, while cruise missiles are rocket-powered only in the initial phase of flight.
2. Agni-V is a medium-range supersonic cruise missile, while BrahMos is a solid-fuelled intercontinental ballistic missile.
Which of the statements given above is/are correct?
(a) 2 only
(b) 1 only
(c) Neither 1 nor 2
(d) Both 1 and 2
Show answer
Answer: (c) — Ballistic missiles are rocket-powered and follow a high arc, while cruise missiles are jet-propelled and fly low, so statement 1 is reversed. Agni-V is an intercontinental ballistic missile and BrahMos is a supersonic cruise missile, so statement 2 is reversed too.
Q6. (2024) Consider the following aircraft:
1. Rafael
2. MiG-29
3. Tejas MK-1
How many of the above are considered fifth generation fighter aircraft?
(a) All three
(b) Only two
(c) None
(d) Only one
Show answer
Answer: (c) — Rafale and Tejas Mk-1 are fourth-generation class fighters and the MiG-29 is also a fourth-generation fighter, so none is a fifth-generation aircraft.
Q7. (2025) With reference to Unmanned Aerial Vehicles (UAVs), consider the following statements:
1. All types of UAVs can do vertical landing.
2. All types of UAVs can do automated hovering.
3. All types of UAVs can use battery only as a source of power supply.
How many of the statements given above are correct?
(a) None
(b) All the three
(c) Only one
(d) Only two
Show answer
Answer: (a) — Fixed-wing and fuel-powered UAVs cannot land vertically, hover automatically or run only on batteries, so none of the 'all types' statements is correct.
Q8. (2025) With reference to India's defence, consider the following pairs:
Aircraft type : Description
1. Dornier-228 : Maritime patrol aircraft
2. IL-76 : Supersonic combat aircraft
3. C-17 Globemaster III : Military transport aircraft
How many of the pairs given above are correctly matched?
(a) Only two
(b) None
(c) All the three
(d) Only one
Show answer
Answer: (a) — Dornier-228 is a maritime patrol aircraft and the C-17 Globemaster III is a military transport. The IL-76 is a transport aircraft, not a supersonic combat plane. Two pairs are right.
Q9. (2026, provisional key) Which of the following statements with regard to stealth technology is/are correct?
1. Stealth objects have a very small radar cross-section and are coated with Radar Absorbing Material.
2. Stealth objects can be detected using specific frequencies.
3. Stealth objects are coated with metamaterials to increase the scattering of electromagnetic radiation.
Select the answer using the code given below :
(a) 1 only
(b) 2 and 3 only
(c) 1, 2 and 3
(d) 1 and 2 only
Show answer
Answer: (d) — Stealth aircraft have a very small radar cross-section and radar-absorbing coatings, and radars on particular frequencies can still detect them. Metamaterials are used to reduce, not increase, scattering, so statements 1 and 2.
Q10. (2026, provisional key) Which of the following statements with regard to Black Boxes used in modern aircrafts is/are correct?
1. They carry a beacon emitting red light pulses to facilitate underwater detection.
2. They record both the cockpit voice and flight data.
3. Their memory units are made using either stainless steel or titanium.
Select the answer using the code given below :
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 only
(d) 1, 2 and 3
Show answer
Answer: (b) — Black boxes record cockpit voice and flight data, and their memory units are protected by stainless steel or titanium. The underwater locator beacon sends acoustic pings, not red light pulses, so statements 2 and 3.
Q11. (2026, provisional key) Which of the following statements with regard to drone swarms is/are correct ?
1. They use Terahertz band of frequency to communicate with the command centre.
2. Individual drones in the swarm can communicate with other drones in the swarm.
3. GPS Spoofing is a commonly used technique to counter drone swarm attack.
Select the answer using the code given below :
(a) 2 and 3 only
(b) 1, 2 and 3
(c) 1 only
(d) 1 and 2 only
Show answer
Answer: (a) — Drones in a swarm communicate with each other, and GPS spoofing is a common way to counter a swarm. Swarms do not use the terahertz band to talk to the command centre, so statements 2 and 3.
Mains Practice Questions
Use these to frame full-length answers. You don't have to answer one exactly — they show the angles UPSC tests, so let them guide which points you cover.
Distinguish between ballistic and cruise missiles with Indian examples, and explain India's missile defence efforts.
How are drones and drone swarms changing warfare? What counter-measures exist, and what is India's progress?
Explain stealth technology and why it is not perfect invisibility.
What does 'fifth-generation fighter' mean? Assess India's AMCA programme and the need for indigenous engines.
Evaluate the role of DRDO and private industry in self-reliance in defence.
UPSC Mains — Previous Years’ Questions on this topic (last 10 years)
No direct GS Mains question has been asked specifically on this topic in the last decade — it is primarily a Prelims area. Use the practice prompts above to stay exam-ready.