GS Paper III · Science & Technology · Defence
⚙ Vikas Engine & Kaveri Engine — India's Propulsion Story
Vikas Engine (ISRO) · Named after Vikram Sarabhai · PSLV/GSLV/LVM3 · Throttling Test · Gaganyaan · Kaveri Engine (DRDO/GTRE) · 40-year journey · Dry Kaveri · Kaveri 2.0 · 1,000-sec test · AMCA · Updated 2024–2026 · PYQs & MCQs
⚙
Vikas Engine — Definition & Background
Named after Vikram Sarabhai · ISRO's Workhorse Liquid Engine
📖 Definition (Exam-Ready)
The Vikas Engine (named in honour of Dr. Vikram Ambalal Sarabhai, founder of ISRO) is a family of liquid-fuelled rocket engines developed by ISRO's Liquid Propulsion Systems Centre (LPSC) during the 1970s. It is the workhorse liquid engine powering the second stages of PSLV and GSLV, and the core liquid stage of LVM3.
Inspiration: Derived from the European Viking Engine (Société Européenne de Propulsion / SEP, France). Technology transferred in 1974. First successful test: 1985. Initially used imported French components — later replaced with fully indigenous parts.
Propellant: UDMH (fuel) + N₂O₄ (oxidiser) — earth-storable, hypergolic (self-igniting on contact, no igniter needed)
Inspiration: Derived from the European Viking Engine (Société Européenne de Propulsion / SEP, France). Technology transferred in 1974. First successful test: 1985. Initially used imported French components — later replaced with fully indigenous parts.
Propellant: UDMH (fuel) + N₂O₄ (oxidiser) — earth-storable, hypergolic (self-igniting on contact, no igniter needed)
🏍 "The Reliable Middle Stage" Analogy
In a relay race, the first runner (solid booster) does the hard initial sprint. The final runner (cryogenic engine) does the precision finish. The Vikas engine is the crucial middle runner — it takes over after the solid stage burns out and carries the rocket into the upper atmosphere before the cryogenic upper stage takes over for orbit insertion. Every ISRO rocket with liquid stages uses a Vikas variant.
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Named After
Dr. Vikram Ambalal Sarabhai (1919–1971) — Father of India's Space Programme. Founded ISRO in 1969. Established Thumba Equatorial Rocket Launching Station (1963). Envisioned using space for national development.
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Developed By
ISRO's Liquid Propulsion Systems Centre (LPSC), Bengaluru (and Mahendragiri). Technology licensed from SEP, France (1974). HAL signed MoU with Safran (successor to SEP) in 2023 for AMCA engine collaboration.
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Propellants
UDMH (Unsymmetrical Dimethylhydrazine) — fuel. Preferred over hydrazine (more stable, auto-ignites at higher temperature).
N₂O₄ (Nitrogen Tetroxide) — oxidiser.
Hypergolic = self-igniting on contact → no igniter needed → high reliability.
N₂O₄ (Nitrogen Tetroxide) — oxidiser.
Hypergolic = self-igniting on contact → no igniter needed → high reliability.
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How the Vikas Engine Works — With Animation
Liquid Propulsion · Turbopump · Combustion · Thrust
⚙ Animation: Vikas Engine — Liquid Propulsion System
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Hypergolic Propellants — The Big Advantage
UDMH + N₂O₄ are hypergolic — they spontaneously ignite when they come into contact with each other. No igniter spark needed. This means:
✅ Extremely reliable (no ignition failure possible)
✅ Can be restarted multiple times (just open valve)
✅ Both liquids at room temperature (earth-storable)
❌ Both are highly toxic — must handle with care
✅ Extremely reliable (no ignition failure possible)
✅ Can be restarted multiple times (just open valve)
✅ Both liquids at room temperature (earth-storable)
❌ Both are highly toxic — must handle with care
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Throttling — Jan 2023 Milestone Current Affairs
January 2023: First-ever throttling test of Vikas Engine — successfully achieved 67% thrust level for 43 seconds.
Throttling = controlling thrust by varying propellant flow rate. Like pressing an accelerator partially. Enables:
✅ Fine-tuning orbital injection speed
✅ Precise trajectory corrections
✅ Critical for Gaganyaan — thrust must be modulated for crew safety
Throttling = controlling thrust by varying propellant flow rate. Like pressing an accelerator partially. Enables:
✅ Fine-tuning orbital injection speed
✅ Precise trajectory corrections
✅ Critical for Gaganyaan — thrust must be modulated for crew safety
💡 Where is Vikas Used — In Every Major ISRO Rocket
PSLV: Stage 2 (PS2) + Stage 4 — Vikas-4B variant
GSLV Mk I: Stage 2 (GS2) + 4 liquid strap-ons — Vikas-4 (GS2) + Vikas-2 (strap-ons)
GSLV Mk II: Stage 2 + 4 strap-ons — Vikas-4B (GS2) + Vikas-2B (strap-ons)
LVM3: L110 core liquid stage — 2 × Vikas-X engines (combined 1,598 kN thrust)
GSLV Mk I: Stage 2 (GS2) + 4 liquid strap-ons — Vikas-4 (GS2) + Vikas-2 (strap-ons)
GSLV Mk II: Stage 2 + 4 strap-ons — Vikas-4B (GS2) + Vikas-2B (strap-ons)
LVM3: L110 core liquid stage — 2 × Vikas-X engines (combined 1,598 kN thrust)
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Vikas Engine — Variants, Specs & Gaganyaan
HTVE · HPVE · Variants Table · Throttling · Gaganyaan Role
| Variant | Fuel | Used In | Stage Role | Thrust / Note |
|---|---|---|---|---|
| Vikas-2 | UDMH / N₂O₄ | GSLV Mk-I | L40H Strap-on (booster) | Original strap-on variant |
| Vikas-2B | UH 25 / N₂O₄ | GSLV Mk-II | L40H Strap-on (booster) | UH 25 = 75% UDMH + 25% hydrazine blend |
| Vikas-X | UH 25 / N₂O₄ | LVM3 | L110 core liquid stage | Two Vikas-X = 1,598 kN combined · 55t propellant |
| Vikas-4 | UDMH / N₂O₄ | GSLV Mk-I, PSLV | GS2 / PS2 (second stage) | Second stage main engine |
| Vikas-4B | UH 25 / N₂O₄ | GSLV Mk-II, PSLV | GS2 / PS2 (second stage) | Current standard second-stage variant |
| HTVE (High Thrust Vikas) | — | GSLV (second stage) | Modified Vikas-2B | 800 kN (6% higher chamber pressure at 62 bar) |
| HPVE (High Pressure Vikas) | — | Future GSLV / LVM3(M) | Booster + first stage | Under development · Higher thrust · For future rockets |
Vikas Engine in Gaganyaan — Human Spaceflight
⭐ Vikas for Gaganyaan — High-Stakes Application
A high-thrust variant of the Vikas Engine, specifically modified for the Gaganyaan mission, was successfully test-fired for 25 seconds at ISRO's Propulsion Complex (IPRC), Mahendragiri — testing resilience under conditions exceeding normal operating parameters.
TV-D1 (Test Vehicle Abort Mission): A modified Vikas engine powers the TV-D1 vehicle — testing India's Crew Escape System (CES). In the event of a rocket emergency after liftoff, the CES uses high-burn-rate solid motors to quickly pull the crew module away to safety. The TV-D1 test validated this abort system — crucial for crew safety in Gaganyaan.
Why throttling matters for Gaganyaan: During liftoff, the rocket's acceleration must not exceed safe G-force limits for the crew (~3–4G). Vikas engine throttling allows ISRO to modulate thrust in real time — if the rocket accelerates too fast, thrust is reduced. Jan 2023 throttling test (67% for 43 seconds) was a critical step toward human-rating the engine.
TV-D1 (Test Vehicle Abort Mission): A modified Vikas engine powers the TV-D1 vehicle — testing India's Crew Escape System (CES). In the event of a rocket emergency after liftoff, the CES uses high-burn-rate solid motors to quickly pull the crew module away to safety. The TV-D1 test validated this abort system — crucial for crew safety in Gaganyaan.
Why throttling matters for Gaganyaan: During liftoff, the rocket's acceleration must not exceed safe G-force limits for the crew (~3–4G). Vikas engine throttling allows ISRO to modulate thrust in real time — if the rocket accelerates too fast, thrust is reduced. Jan 2023 throttling test (67% for 43 seconds) was a critical step toward human-rating the engine.
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UH 25 Fuel — What is it?
UH 25 = 75% UDMH + 25% Hydrazine (N₂H₄) blend.
Why blend? Pure hydrazine is too unstable (auto-ignites at lower temperature). Pure UDMH alone has lower performance. UH 25 is a compromise: more stable than pure hydrazine + slightly better performance than pure UDMH.
Used in newer GSLV Mk-II and LVM3 variants for slightly better ISP.
Why blend? Pure hydrazine is too unstable (auto-ignites at lower temperature). Pure UDMH alone has lower performance. UH 25 is a compromise: more stable than pure hydrazine + slightly better performance than pure UDMH.
Used in newer GSLV Mk-II and LVM3 variants for slightly better ISP.
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Manufacturing & HAL-Safran MoU (2023)
Vikas was originally based on French Viking engine technology (SEP, 1974). Initially imported components — now fully indigenised. HAL manufactures Vikas engines for ISRO.
HAL-Safran MoU (2023): HAL signed an MoU with Safran (parent company of original SEP) — this time for a different purpose: collaborating on the engine for India's AMCA (Advanced Medium Combat Aircraft) 5th-generation fighter.
HAL-Safran MoU (2023): HAL signed an MoU with Safran (parent company of original SEP) — this time for a different purpose: collaborating on the engine for India's AMCA (Advanced Medium Combat Aircraft) 5th-generation fighter.
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Kaveri Engine — Definition & Overview
DRDO · GTRE · Afterburning Turbofan · LCA Tejas
📖 Kaveri Engine — Definition (Exam-Ready)
The GTRE GTX-35VS Kaveri is an afterburning turbofan jet engine under development by the Gas Turbine Research Establishment (GTRE) — a laboratory under DRDO — in Bengaluru. It was originally intended to power the HAL Tejas fighter jet.
Type: Low-bypass afterburning turbofan (like engines that power supersonic fighter jets)
Target thrust: 81 kN (wet/afterburner) | Current dry thrust achieved: 49–51 kN (Kaveri Dry variant)
Named after: River Kaveri (Cauvery) of South India
Type: Low-bypass afterburning turbofan (like engines that power supersonic fighter jets)
Target thrust: 81 kN (wet/afterburner) | Current dry thrust achieved: 49–51 kN (Kaveri Dry variant)
Named after: River Kaveri (Cauvery) of South India
✈ How a Turbofan Jet Engine Works (Kaveri Type)
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GTRE — Who Develops It
Gas Turbine Research Establishment (GTRE) — Bengaluru. A lab under DRDO. 240 scientists, 400 technicians, 64-acre campus. Started Kaveri programme in 1986. Also developing Marine Gas Turbine (Kaveri derivative) and armoured platform turbocharger.
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Original Goal
Power India's HAL Tejas Light Combat Aircraft (LCA) as an indigenous engine — ending dependence on imported GE F404/F414 engines. Target: 81 kN (wet thrust). Delinked from Tejas in September 2008 — could not meet thrust requirements on time.
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New Goal (After 2014)
Dry Kaveri (non-afterburner, 49–51 kN): Power DRDO Ghatak stealth UCAV.
Kaveri 2.0 (with new afterburner, 83–85 kN): Future power for Tejas Mk1A / Tejas Mk2 fleet.
AMCA engine: New 120 kN engine with Safran IP ownership for India.
Kaveri 2.0 (with new afterburner, 83–85 kN): Future power for Tejas Mk1A / Tejas Mk2 fleet.
AMCA engine: New 120 kN engine with Safran IP ownership for India.
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Kaveri's 40-Year Journey — Timeline & Key Events
1986–2026 · Setbacks · Progress · Lessons
86
1986 — Programme Launched
DRDO authorised to develop indigenous engine for LCA. Budget: ₹383 crore. Target: 81 kN wet thrust, 73 kN dry. Design commenced at GTRE, Bengaluru.
98
1998 — Nuclear Tests Setback
India's Pokhran-II nuclear tests → US-led international sanctions. Critical components and technology denied. Development severely hampered for years. Budget eventually ballooned to ₹2,839 crore by 2009.
08
September 2008 — Officially Delinked from Tejas
Kaveri formally delinked from Tejas programme — could not deliver required 81 kN thrust in time. Tejas flew with GE F404 instead. DRDO Chairman Dr. Samir Kamat later admitted: "The mistake was developing engine and platform together — that's never done." India procured 99 GE F-404 engines (₹5,375 crore deal, 2021) for Tejas Mk1A.
10
2010 — Prototype K9 Flown in Russia
Kaveri prototype K9 flight-tested on Ilyushin Il-76 at Gromov Flight Research Institute, Russia. By 2010: 9 full prototype engines + 4 core engines built. 1,880 test hours logged. Core engine met dry thrust requirement. Altitude testing complete.
21
2021 — 3,217 Hours Total Testing
By November 2021: 9 full prototype engines + 4 core engines built. 3,217 hours of engine testing. Completed altitude trials. Dry thrust achieved: 46 kN. Wet thrust: 70.5 kN (vs target of 81 kN). Programme effectively stalled from 2014.
22
Oct 2022 & Feb 2023 — High Altitude Tests (Russia)
High-altitude tests at Gromov Flight Research Institute, Russia. Engine mounted on Il-76 testbed. Dry thrust achieved: 48.5 kN — surpassing simulated target of 46 kN. Initial Flight Release (IFR) certification expected by 2024. Godrej Aerospace won contract for 8 modules of Dry Kaveri engine (Feb 2023, ₹500 crore investment). 3 engines upgraded to K9+ standard.
24
2024 — Major Progress Year Current Affairs
Jan 2024: GTRE commenced afterburner section development — targeting 80 kN thrust. Tenders issued for components.
Jun 2024: Report confirmed weight reduced to 1,180 kg. Advancements in turbines, compressors, gearboxes, ECS, metallurgy.
Jun 2024 (Safran Audit): Safran audit cleared Kaveri for aircraft integration — 5 prototypes (K5–K9) tested ~145 hours including first-ever idle-to-max-reheat transient test.
Jun 2024: DRDO Chairman Dr. Samir Kamat announced Dry Kaveri derivative integration into LCA-Tejas Trainer (LSP PV-5/PV-6) as Flying Test Bed.
Nov 2024: BrahMos Aerospace developing 29 kN afterburner section for Dry Kaveri — targeting 80 kN total thrust.
Dec 2024: Dry Kaveri approved for in-flight tests on Il-76 testbed.
Jun 2024: Report confirmed weight reduced to 1,180 kg. Advancements in turbines, compressors, gearboxes, ECS, metallurgy.
Jun 2024 (Safran Audit): Safran audit cleared Kaveri for aircraft integration — 5 prototypes (K5–K9) tested ~145 hours including first-ever idle-to-max-reheat transient test.
Jun 2024: DRDO Chairman Dr. Samir Kamat announced Dry Kaveri derivative integration into LCA-Tejas Trainer (LSP PV-5/PV-6) as Flying Test Bed.
Nov 2024: BrahMos Aerospace developing 29 kN afterburner section for Dry Kaveri — targeting 80 kN total thrust.
Dec 2024: Dry Kaveri approved for in-flight tests on Il-76 testbed.
25-26
2025–2026 — Flight Testing & New Goals Latest
May 2025: GTRE secured approval to integrate Dry Kaveri (with new afterburner) into an older LSP LCA-Tejas for validation testing — first time Kaveri tested on a manned fighter platform.
May 2025: Kaveri undergoing flight tests in Russia on Il-76 — only 25 hours of testing remaining (as of May 28, 2025).
Sep 2025: DRDO DG Dr. K. Rajalakshmi Menon confirmed Kaveri will soon be tested on LCA Tejas — "to close the end-to-end development loop" and instil "last-mile confidence."
Kaveri 2.0 targets: 83–85 kN wet thrust. Expected to deliver domestically viable alternative to F404-IN20.
Certification timeline: Dry Kaveri certification by 2032. Limited production by 2025–26 for Ghatak UCAV.
Russia flying testbed: Final testing phase in Russia (Gromov Institute) scheduled — Kaveri replacing one of four Il-76 engines.
May 2025: Kaveri undergoing flight tests in Russia on Il-76 — only 25 hours of testing remaining (as of May 28, 2025).
Sep 2025: DRDO DG Dr. K. Rajalakshmi Menon confirmed Kaveri will soon be tested on LCA Tejas — "to close the end-to-end development loop" and instil "last-mile confidence."
Kaveri 2.0 targets: 83–85 kN wet thrust. Expected to deliver domestically viable alternative to F404-IN20.
Certification timeline: Dry Kaveri certification by 2032. Limited production by 2025–26 for Ghatak UCAV.
Russia flying testbed: Final testing phase in Russia (Gromov Institute) scheduled — Kaveri replacing one of four Il-76 engines.
💡 PM Modi's Independence Day Speech 2025 — Kaveri Context
PM Narendra Modi in his Independence Day speech 2025 asked: "Should the jet engine for our Made in India fighter jets be ours or not?" — signalling top-level push for indigenous aero-engine capability. India currently buys 99 GE F-404 engines (Tejas Mk1A) and will buy GE F-414 engines for Tejas Mk2 — worth thousands of crores. Kaveri 2.0 and the AMCA engine (Safran collaboration) aim to end this dependence.
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Kaveri — What's Happening Now (2024–26)
Dry Kaveri · Kaveri 2.0 · Ghatak UCAV · AMCA Engine · Lessons
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Dry Kaveri → Powers Ghatak UCAV
The Dry Kaveri (non-afterburning) variant — 49–51 kN thrust — is being developed to power DRDO's Ghatak stealth UCAV (Unmanned Combat Aerial Vehicle). Ghatak is India's first indigenous stealth drone. GTRE aims to integrate Kaveri on Ghatak by 2026.
Godrej Aerospace contracted to supply 8 modules of Kaveri Derivative Engine (KDE) — the first private firm to produce jet engine modules for a DRDO engine. ₹500 crore facility in Khalapur (70 km from Mumbai).
Godrej Aerospace contracted to supply 8 modules of Kaveri Derivative Engine (KDE) — the first private firm to produce jet engine modules for a DRDO engine. ₹500 crore facility in Khalapur (70 km from Mumbai).
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Kaveri 2.0 — The Upgraded Target
New afterburner module developed by BrahMos Aerospace (29 kN) added to Dry Kaveri core → total 83–85 kN wet thrust. If achieved, this matches the F404-IN20 engines currently powering Tejas Mk1A (84 kN).
Challenge: Current Kaveri weight = 1,180 kg vs F404 = 1,036 kg, F414 = 1,110 kg. GTRE working on weight reduction through lighter alloys and advanced manufacturing.
Challenge: Current Kaveri weight = 1,180 kg vs F404 = 1,036 kg, F414 = 1,110 kg. GTRE working on weight reduction through lighter alloys and advanced manufacturing.
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Testing on LCA Tejas — Landmark Step (2025)
GTRE received approval (May 2025) to integrate Dry Kaveri with new afterburner into an older LSP LCA-Tejas for validation testing. Confirmed by DRDO DG Dr. K. Rajalakshmi Menon (Sep 2025): "This will close the end-to-end development loop." Two trainer prototypes (PV-5, PV-6) being repurposed as flying testbeds.
This is the first time a Kaveri variant will be tested on a manned Indian fighter aircraft.
This is the first time a Kaveri variant will be tested on a manned Indian fighter aircraft.
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AMCA Engine — The Next Frontier
For India's AMCA (5th-generation fighter), GTRE + Safran are jointly developing a 120 kN engine based on M88 (Rafale's engine) technology — with full IP ownership for India. This is a different engine from Kaveri but uses technologies matured through the Kaveri programme.
Lesson from Kaveri: Don't develop engine and aircraft together. AMCA engine programme starts 5–7 years before AMCA airframe.
Lesson from Kaveri: Don't develop engine and aircraft together. AMCA engine programme starts 5–7 years before AMCA airframe.
⭐ The Kaveri Lesson — DRDO Chairman's Candid Admission
Dr. Samir V. Kamat, Chairman DRDO, said at Khatre Memorial Talks: "The mistake we made was to develop an engine and platform together. That's never done. You design a platform around the available engine and engine development is a continuous process — that was a rookie mistake."
Global practice: Engine developed first (takes 15–20 years) → Aircraft designed around the engine. India tried to do both simultaneously → both delayed each other → Tejas had to use American engines → strategic vulnerability exposed (2021 sanctions risk, supply chain issues).
What Kaveri did give India: India's first domestically designed jet engine core. Critical knowledge in turbine blades (most difficult component), compressor design, materials science, metallurgy, FADEC (Full Authority Digital Engine Control — KADECU developed by DARE, Bengaluru). These learnings are now being applied to AMCA engine.
Global practice: Engine developed first (takes 15–20 years) → Aircraft designed around the engine. India tried to do both simultaneously → both delayed each other → Tejas had to use American engines → strategic vulnerability exposed (2021 sanctions risk, supply chain issues).
What Kaveri did give India: India's first domestically designed jet engine core. Critical knowledge in turbine blades (most difficult component), compressor design, materials science, metallurgy, FADEC (Full Authority Digital Engine Control — KADECU developed by DARE, Bengaluru). These learnings are now being applied to AMCA engine.
🧠 Kaveri's Spin-offs — Not Wasted
Even though Kaveri failed for Tejas, the programme produced:
1. KADECU — Kaveri Digital Engine Control Unit (FADEC) — developed by DARE, Bengaluru
2. Kaveri Marine Gas Turbine — for Indian Navy ships
3. Military-grade turbocharger — for armoured vehicles
4. BHEL-GTRE collaboration (Sep 2024) — for Marine Gas Turbine and heavy industrial turbines
5. AMAGB (Aircraft Mounted Accessory Gearbox) — designed for Kaveri integration
6. Knowledge in turbine design, metallurgy, combustor development — used in AMCA engine
1. KADECU — Kaveri Digital Engine Control Unit (FADEC) — developed by DARE, Bengaluru
2. Kaveri Marine Gas Turbine — for Indian Navy ships
3. Military-grade turbocharger — for armoured vehicles
4. BHEL-GTRE collaboration (Sep 2024) — for Marine Gas Turbine and heavy industrial turbines
5. AMAGB (Aircraft Mounted Accessory Gearbox) — designed for Kaveri integration
6. Knowledge in turbine design, metallurgy, combustor development — used in AMCA engine
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Vikas vs Kaveri — Complete Comparison
Type · Application · Status · Propellant · Thrust
| Feature | ⚙ Vikas Engine | ✈ Kaveri Engine |
|---|---|---|
| Type | Liquid bipropellant rocket engine (no rotating parts) | Afterburning turbofan jet engine (has rotating compressor + turbine) |
| Application | Space rockets (PSLV/GSLV/LVM3) — launches satellites | Fighter aircraft (LCA Tejas / Ghatak UCAV) — powers aircraft |
| Propellant / Fuel | UDMH (fuel) + N₂O₄ (oxidiser) — carries own oxygen | Aviation kerosene (fuel) + atmospheric O₂ (oxidiser from air) |
| Works in space? | ✅ Yes — carries own oxidiser | ❌ No — needs atmospheric oxygen |
| Rotating parts? | ❌ No (only turbopump for fuel/oxidiser pressure) | ✅ Yes — fan, multi-stage compressor, turbine all rotate |
| Thrust | 799 kN (Vikas-4B) / 800 kN (HTVE variant) | Target: 81 kN wet / 73 kN dry. Current: 49–51 kN (Dry variant) |
| Developer | ISRO — LPSC, Bengaluru + Mahendragiri | DRDO — GTRE, Bengaluru |
| Based on | French Viking engine (SEP technology, 1974) | Indigenous design (some Russian collaboration for testing) |
| Status | 🟢 Fully Operational — powers every major ISRO rocket | 🔵 Under development — Dry variant near certification; Kaveri 2.0 by ~2032 |
| Key milestone | Jan 2023: First throttling test (67%, 43 sec) | May 2025: Approved for manned LCA-Tejas testing |
| Named after | Dr. Vikram Ambalal Sarabhai (ISRO founder) | River Kaveri (Cauvery) of South India |
| Private sector | HAL manufactures; PSLV 50% dev to private sector | Godrej Aerospace — 8 Dry Kaveri engine modules (first private jet engine module in India) |
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UPSC PYQs — Vikas & Kaveri
Actual Questions · Verified Answers
⭐ UPSC Prelims — Vikas Engine Propellants & ApplicationsRepeated Pattern
With reference to ISRO's Vikas Engine, consider the following statements:
1. The Vikas Engine uses liquid hydrogen and liquid oxygen as propellants — making it a cryogenic engine.
2. The Vikas Engine is used in the second stage of both PSLV and GSLV rockets.
3. The Vikas Engine is named after Dr. Vikram Sarabhai, the founder of India's space programme.
1. The Vikas Engine uses liquid hydrogen and liquid oxygen as propellants — making it a cryogenic engine.
2. The Vikas Engine is used in the second stage of both PSLV and GSLV rockets.
3. The Vikas Engine is named after Dr. Vikram Sarabhai, the founder of India's space programme.
- (a) 1 and 2 only
- (b) 2 only
- (c) 2 and 3 only ✅
- (d) 1, 2 and 3
Statement 1 ✗ WRONG: Vikas is NOT a cryogenic engine. It uses UDMH (fuel) + N₂O₄ (oxidiser) — earth-storable bipropellants at room temperature. Cryogenic engines (CE-7.5, CE-20) use liquid hydrogen (-253°C) + liquid oxygen (-183°C). Vikas is a liquid earth-storable hypergolic engine — hypergolic means self-igniting without a separate igniter.
Statement 2 ✅ Correct: Vikas powers: PSLV Stage 2 (PS2) — Vikas-4B variant. GSLV Stage 2 (GS2) — Vikas-4/4B. Also powers GSLV strap-ons (Vikas-2/2B) and LVM3 core stage (Vikas-X, two engines).
Statement 3 ✅ Correct: Named after Dr. Vikram Ambalal Sarabhai (1919–1971) — founder of ISRO, established Thumba space programme (1963). Vikas = Vikram Ambalal Sarabhai.
Statement 2 ✅ Correct: Vikas powers: PSLV Stage 2 (PS2) — Vikas-4B variant. GSLV Stage 2 (GS2) — Vikas-4/4B. Also powers GSLV strap-ons (Vikas-2/2B) and LVM3 core stage (Vikas-X, two engines).
Statement 3 ✅ Correct: Named after Dr. Vikram Ambalal Sarabhai (1919–1971) — founder of ISRO, established Thumba space programme (1963). Vikas = Vikram Ambalal Sarabhai.
⭐ UPSC Prelims — Kaveri Engine & LCA TejasCurrent Affairs 2025
Consider the following about India's Kaveri Engine:
1. Kaveri is a cryogenic rocket engine developed by ISRO to replace the CE-20 engine in LVM3.
2. The Kaveri engine was officially delinked from the Tejas programme in 2008 as it could not deliver the required thrust in time.
3. The Dry Kaveri variant (without afterburner) is being developed to power the DRDO Ghatak stealth UCAV.
1. Kaveri is a cryogenic rocket engine developed by ISRO to replace the CE-20 engine in LVM3.
2. The Kaveri engine was officially delinked from the Tejas programme in 2008 as it could not deliver the required thrust in time.
3. The Dry Kaveri variant (without afterburner) is being developed to power the DRDO Ghatak stealth UCAV.
- (a) 1 and 2 only
- (b) 2 and 3 only ✅
- (c) 1 and 3 only
- (d) 1, 2 and 3
Statement 1 ✗ WRONG: Kaveri is NOT a cryogenic rocket engine. It is an afterburning turbofan jet engine developed by DRDO's GTRE — designed for aircraft (fighter jets), not rockets. It uses aviation kerosene + atmospheric oxygen. ISRO's cryogenic engines are CE-7.5 (GSLV) and CE-20 (LVM3) — entirely different technology. Kaveri has nothing to do with LVM3.
Statement 2 ✅ Correct: Kaveri officially delinked from Tejas programme in September 2008. Target was 81 kN wet thrust; achieved only ~70.5 kN wet and 46 kN dry. Tejas now uses GE F404 (Mk1/Mk1A) and will use GE F414 (Mk2).
Statement 3 ✅ Correct: The Dry Kaveri (non-afterburning, 49–51 kN) is being developed for DRDO Ghatak — India's indigenous stealth UCAV. GTRE aims to integrate Kaveri on Ghatak by 2026. Godrej Aerospace has been contracted to manufacture 8 modules of the Dry Kaveri engine.
Statement 2 ✅ Correct: Kaveri officially delinked from Tejas programme in September 2008. Target was 81 kN wet thrust; achieved only ~70.5 kN wet and 46 kN dry. Tejas now uses GE F404 (Mk1/Mk1A) and will use GE F414 (Mk2).
Statement 3 ✅ Correct: The Dry Kaveri (non-afterburning, 49–51 kN) is being developed for DRDO Ghatak — India's indigenous stealth UCAV. GTRE aims to integrate Kaveri on Ghatak by 2026. Godrej Aerospace has been contracted to manufacture 8 modules of the Dry Kaveri engine.
⭐ Expected Mains 2026250 Words | 15 Marks
"The Vikas and Kaveri engine programmes represent two different trajectories of India's propulsion technology development. Critically analyse their significance, achievements, and lessons for India's future aerospace ambitions."
Vikas (success story): French Viking engine tech (1974) → fully indigenised over 50 years → powers every major ISRO rocket: PSLV/GSLV/LVM3 → 799 kN thrust → hypergolic UDMH+N₂O₄ → Jan 2023 throttling test (67%, 43 sec) → Gaganyaan role (human-rated variant) → TV-D1 abort test → HAL-Safran MoU 2023 (AMCA engine) → 50% PSLV tech going to private sector.
Kaveri (complex story): 1986 started → 1998 sanctions disrupted → 2008 delinked from Tejas → ₹2,839 crore spent → 9 prototypes + 3,217 test hours → 46 kN dry vs 81 kN target → But: Oct 2022-Feb 2023 Russia tests (48.5 kN) → Jan 2024 afterburner work begins → Jun 2024 Safran audit clears for integration → May 2025: approved for LCA Tejas manned testing → Jan 2026: 12-min+ Russia combustor test → Kaveri 2.0 target 83-85 kN → Godrej Aerospace (private, ₹500 cr) producing modules → Dry Kaveri for Ghatak UCAV.
Lessons: DRDO Chairman admitted: "Never develop engine and aircraft simultaneously." India must have sovereign engine capability (PM Modi's Independence Day 2025 speech). Only USA, Russia, UK, France, China have full engine sovereignty. Kaveri gave India: turbine design, FADEC (KADECU), marine gas turbine, metallurgy — valuable even without Tejas success. AMCA engine: Safran collaboration for 120 kN engine with India IP — learning from Kaveri mistake.
Kaveri (complex story): 1986 started → 1998 sanctions disrupted → 2008 delinked from Tejas → ₹2,839 crore spent → 9 prototypes + 3,217 test hours → 46 kN dry vs 81 kN target → But: Oct 2022-Feb 2023 Russia tests (48.5 kN) → Jan 2024 afterburner work begins → Jun 2024 Safran audit clears for integration → May 2025: approved for LCA Tejas manned testing → Jan 2026: 12-min+ Russia combustor test → Kaveri 2.0 target 83-85 kN → Godrej Aerospace (private, ₹500 cr) producing modules → Dry Kaveri for Ghatak UCAV.
Lessons: DRDO Chairman admitted: "Never develop engine and aircraft simultaneously." India must have sovereign engine capability (PM Modi's Independence Day 2025 speech). Only USA, Russia, UK, France, China have full engine sovereignty. Kaveri gave India: turbine design, FADEC (KADECU), marine gas turbine, metallurgy — valuable even without Tejas success. AMCA engine: Safran collaboration for 120 kN engine with India IP — learning from Kaveri mistake.
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Practice MCQs — Vikas & Kaveri
10 Questions · Click to Attempt
📝 10 MCQs — All Key Concepts + 2024–26 Current Affairs
Q1. The Vikas Engine uses "hypergolic" propellants. What does hypergolic mean, and which propellants does Vikas use?
- (a) Hypergolic means cryogenic — Vikas uses liquid hydrogen and liquid oxygen kept at extremely low temperatures
- (b) Hypergolic means the fuel burns at hypersonic temperatures — Vikas uses solid HTPB propellant
- (c) Hypergolic means the propellants spontaneously ignite when they contact each other without any separate igniter — Vikas uses UDMH (fuel) + N₂O₄ (oxidiser), both storable at room temperature ✅
- (d) Hypergolic means the engine can start hypersonically — Vikas uses UH 25 fuel with atmospheric oxygen as oxidiser
✅ (c). Hypergolic propellants: when fuel and oxidiser come into contact, they spontaneously ignite — no spark, no igniter system needed. Vikas uses UDMH (Unsymmetrical Dimethylhydrazine) as fuel + N₂O₄ (Nitrogen Tetroxide) as oxidiser. Both are earth-storable liquids (room temperature). Key advantages of hypergolic: (1) No ignition failure possible — highest reliability. (2) Restartable — just open/close valves. (3) Room temperature storage — no cryogenic infrastructure needed. Disadvantages: Both UDMH and N₂O₄ are highly toxic and corrosive. ISP ~293 seconds (lower than cryogenic ~443 seconds). UDMH preferred over pure hydrazine because it auto-ignites at higher temperature (more stable in storage). UH 25 = 75% UDMH + 25% hydrazine — used in newer Vikas-2B, 4B, and Vikas-X variants for slightly better performance.
Q2. Why was the Kaveri engine officially delinked from the LCA Tejas programme in September 2008?
- (a) The Kaveri engine exceeded the required thrust — making it too powerful for the Tejas airframe and requiring a new larger aircraft
- (b) The Kaveri engine could not deliver the required 81 kN (wet) thrust on time — achieving only ~70.5 kN wet and 46 kN dry — forcing Tejas to use the imported GE F404 engine instead ✅
- (c) DRDO decided to redirect Kaveri for use in ISRO's rockets instead, making it unavailable for aircraft applications
- (d) International pressure under MTCR (Missile Technology Control Regime) prevented India from using indigenous jet engines in fighter aircraft
✅ (b). Kaveri's target thrust requirements: Wet (with afterburner): 81 kN. Dry (without afterburner): 73 kN. What was achieved by 2008: Wet ~70.5 kN (short by 10.5 kN). Dry ~46 kN. This shortfall meant Kaveri couldn't provide the Tejas with the necessary thrust-to-weight ratio for acceptable combat performance. Additionally, development was significantly delayed by international sanctions post-1998 nuclear tests — critical components and technology denied. The programme was formally delinked in September 2008. Tejas Mk1 and Mk1A now use American GE F404-IN20 engines (84 kN). India signed a ₹5,375 crore deal in 2021 for 99 GE F-404 engines for Tejas Mk1A. DRDO Chairman Dr. Samir Kamat later admitted the fundamental strategic error: developing engine and aircraft simultaneously — "that's a rookie mistake. You always design the aircraft around an available engine."
Q3. What was significant about the January 2023 Vikas Engine throttling test?
- (a) It was the first-ever throttling test of the Vikas Engine — successfully achieving 67% thrust level for 43 seconds, demonstrating India's ability to modulate rocket engine thrust in real time — critical for Gaganyaan human spaceflight ✅
- (b) The test demonstrated that the Vikas Engine could achieve 200% of its rated thrust using a new turbo-pump modification
- (c) January 2023 was when ISRO transferred the Vikas Engine technology to HAL for the first time, enabling private production
- (d) The test validated the Vikas Engine for cryogenic temperature operation by cooling it to -183°C before firing
✅ (a). January 2023 throttling test: First-ever throttling demonstration of the Vikas Engine. Achieved: 67% thrust level sustained for 43 seconds. Throttling = controlling thrust by managing propellant flow rate. Why 67% matters for Gaganyaan: Human spaceflight requires precise G-force management. During liftoff, if the rocket accelerates too quickly, astronauts experience dangerously high G-forces. The ability to reduce thrust to 67% allows ISRO to modulate acceleration and keep G-forces within safe human limits. Additionally, throttling enables: Precise orbital injection speed fine-tuning. Trajectory correction manoeuvres. Emergency thrust reduction scenarios. The throttling period (43 seconds at 67%) demonstrates the engine can hold a reduced thrust state long enough for practical orbital corrections. This was a critical human-rating milestone for the Gaganyaan programme, which is India's first crewed spaceflight mission targeting 2026.
Q4. Godrej Aerospace winning the contract to manufacture 8 modules of the Dry Kaveri engine was historically significant because:
- (a) It was the first time ISRO transferred rocket engine technology to a private firm — marking the privatisation of India's space programme
- (b) Godrej Aerospace became the first foreign firm to manufacture components for DRDO — a major FDI milestone in defence
- (c) The contract established Kaveri as the world's most affordable jet engine — making India a major engine exporter
- (d) Godrej Aerospace became the first private Indian firm to produce jet engine modules for a DRDO indigenous engine — a breakthrough for India's private defence manufacturing ecosystem ✅
✅ (d). February 2023: Godrej & Boyce's Godrej Aerospace won the GTRE contract to manufacture all 8 modules of 6 Dry Kaveri engines. This was the first time a private Indian firm won a contract to produce jet engine modules for a DRDO-developed indigenous aero-engine. Significance: Validates India's private aerospace manufacturing capability. ₹500 crore investment: Godrej built a 100-acre (400,000 m²) facility in Khalapur, 70 km from Mumbai. Aligns with Make in India and Atmanirbhar Bharat goals. First deliveries expected by late 2024, all 6 engines by August 2025. These 6 Dry Kaveri engines (48 kN each) will be used for certification testing before the engine is cleared for flying on the DRDO Ghatak UCAV. Separate from ISRO's activities (option a wrong — Vikas/SSLV tech transfers are ISRO, not DRDO Kaveri). Godrej is an Indian company, not foreign (option b wrong).
Q5. The Kaveri Marine Gas Turbine is being developed under which collaboration?
- (a) ISRO and DRDO are jointly developing a marine variant of the Vikas Engine for Indian Navy submarines
- (b) Rolls-Royce and GTRE are developing a ship-borne gas turbine based on British Spey engine technology for the Indian Navy
- (c) BHEL and GTRE announced collaboration in September 2024 to jointly develop the Kaveri Marine Gas Turbine (MGT) and heavy-duty industrial gas turbines — leveraging engine technology matured in the Kaveri programme ✅
- (d) India and Russia signed an agreement for GTRE to manufacture Russian NK-12 marine turbines under licence for Indian warships
✅ (c). September 2024: BHEL (Bharat Heavy Electricals Limited) and GTRE (Gas Turbine Research Establishment, DRDO) announced collaboration to develop: (1) Kaveri Marine Gas Turbine (MGT) — for Indian Navy vessels. (2) Heavy-duty industrial gas turbines. This is an example of Kaveri programme spin-offs — even though the engine didn't power the Tejas, the technology and expertise developed over 40 years has multiple civilian and naval applications. The DRDO Chairman noted that the Kaveri programme also led to: Military-grade turbocharger development for armoured platforms. KADECU (Kaveri Digital Engine Control Unit) — India's indigenous FADEC system developed by DARE, Bengaluru. These spin-offs demonstrate that even "failed" R&D programmes build foundational capabilities. PM Modi's Independence Day 2025 speech emphasised the urgent need for sovereign aero-engine capability — naval engines are one pathway where Kaveri technology finds application.
Q6. The LVM3 core liquid stage (L110) uses which Vikas variant, and how many engines?
- (a) One Vikas-4B engine providing 799 kN thrust — same as used in PSLV second stage
- (b) Two Vikas-X engines together providing ~1,598 kN combined thrust — the L110 stage uses 55 tonnes of UH 25 propellant ✅
- (c) Four Vikas-2 engines mounted in a cluster — same configuration as GSLV strap-on boosters
- (d) One CE-20 cryogenic engine — Vikas is not used in LVM3 at all; it is exclusively in PSLV and GSLV
✅ (b). LVM3 L110 stage: 2 × Vikas-X engines. Combined thrust: ~1,598 kN. Propellant: 55 tonnes of UH 25 (75% UDMH + 25% hydrazine) + N₂O₄. This is the core liquid stage of LVM3 — it ignites on the ground along with the two S200 solid strap-on boosters, all firing simultaneously at liftoff. The L110 burns for ~200 seconds as the S200 boosters separate after ~128 seconds, then L110 continues alone. LVM3 propulsion system overview: Stage 1 (strap-ons): 2 × S200 solid motors (200 tonnes propellant each, 5,150 kN each). Core (liquid): L110 — 2 × Vikas-X (1,598 kN combined). Upper stage (cryogenic): C25 — 1 × CE-20 (200 kN). The future LVM3(M) will replace L110 Vikas stage with SCE-200 semi-cryogenic stage (2,000 kN), boosting LVM3's GTO capacity from 4 to 5 tonnes. CE-20 is not Vikas (option d wrong) — it's a separate cryogenic engine in the upper stage.
Q7. DRDO Chairman Dr. Samir Kamat admitted a "rookie mistake" in India's aero-engine programme. What was this mistake?
- (a) Using imported French technology as the basis for the Vikas Engine rather than developing a fully indigenous design from scratch
- (b) Choosing to build a turbofan engine (Kaveri) for the Tejas instead of a simpler ramjet engine that India had already mastered
- (c) Not partnering with Russia early enough — Russia's Su-30MKI engine partnership could have been used as a template for Kaveri
- (d) Developing the Kaveri engine and the LCA Tejas aircraft simultaneously — globally, aircraft are always designed around an available engine, not the other way around ✅
✅ (d). Dr. Samir V. Kamat, DRDO Chairman, at Khatre Memorial Talks: "The mistake we made was to develop an engine (Kaveri) and platform (LCA Tejas) together. That's never done. You design a platform around the available engine and engine development is a continuous process — that was a rookie mistake." Global aerospace development sequence: Step 1: Develop engine over 15–20 years (engine is the most complex component). Step 2: Design aircraft around the available engine's characteristics (thrust, dimensions, weight, fuel consumption). India reversed this: Kaveri and Tejas were started simultaneously in the late 1980s. Both delayed each other. Tejas couldn't wait for Kaveri → had to use imported GE F404. DRDO's correction for AMCA (5th-gen fighter): AMCA engine development started 5–7 years before AMCA airframe finalisation. Safran collaboration for 120 kN engine with full IP ownership for India. This lesson is now central to India's aerospace strategy. PM Modi's Independence Day 2025 speech also highlighted the urgency of developing sovereign engine capability.
Q8. What is "Kaveri 2.0" and what thrust does it target?
- (a) Kaveri 2.0 is an upgraded Kaveri engine with a new afterburner (29 kN, developed by BrahMos Aerospace) added to the Dry Kaveri core, targeting 83–85 kN wet thrust — potentially enabling it to power the LCA Tejas Mk1A fleet as a domestic F404 alternative ✅
- (b) Kaveri 2.0 is ISRO's next-generation cryogenic engine, replacing CE-20 in LVM3, with 200 kN thrust
- (c) Kaveri 2.0 is a completely new engine design that abandons all previous Kaveri work and starts fresh with a Rolls-Royce collaboration
- (d) Kaveri 2.0 is the marine gas turbine variant targeting 29 kN for Indian Navy frigates
✅ (a). Kaveri 2.0 = Dry Kaveri core (49–51 kN) + new afterburner section (29 kN, developed by BrahMos Aerospace). November 2024: BrahMos Aerospace announced development of 29 kN afterburner for Dry Kaveri. Combined target: 83–85 kN wet thrust. Compare with: GE F404-IN20 (current Tejas Mk1A engine): 84 kN wet. GE F414 (future Tejas Mk2): ~98 kN wet. If Kaveri 2.0 achieves 83–85 kN, it becomes a viable domestic alternative to F404 for the Tejas Mk1A fleet. Expected certification: ~2032. This would end India's reliance on American engines for Tejas Mk1/Mk1A — significant strategic autonomy. Challenge: Kaveri 2.0's weight (~1,180 kg + afterburner) may exceed F404's weight (1,036 kg) — affecting Tejas thrust-to-weight ratio. GTRE is working on weight reduction. The AMCA engine (Safran collaboration, 120 kN) is a separate, more powerful engine for the 5th-generation AMCA fighter — not Kaveri 2.0.
Q9. Which Vikas Engine variant powers the GSLV Mk-II's strap-on liquid boosters?
- (a) Vikas-4B — the same variant used in PSLV second stage (PS2)
- (b) Vikas-X — the high-thrust variant used in LVM3 core stage with 55 tonnes of propellant
- (c) Vikas-2B — using UH 25 / N₂O₄ propellant combination, powering the 4 liquid strap-on boosters of GSLV Mk-II (L40H strap-ons) ✅
- (d) HTVE (High Thrust Vikas Engine) — providing 800 kN thrust from the 62-bar chamber pressure variant
✅ (c). GSLV Mk-II strap-on liquid boosters use Vikas-2B engines. Complete GSLV Mk-II propulsion: Stage 1: S139 solid motor (same as PSLV Stage 1) + 4 liquid strap-ons (Vikas-2B each, L40H configuration). Stage 2: One Vikas-4B engine (GS2 stage). Stage 3: CE-7.5 indigenous cryogenic engine (CUS — Cryogenic Upper Stage). Vikas-2B uses UH 25 (75% UDMH + 25% hydrazine) as fuel and N₂O₄ as oxidiser. "B" suffix = UH 25 propellant variant. Compared with GSLV Mk-I: used Vikas-2 (pure UDMH, not UH 25). The 4 Vikas-2B strap-ons ignite along with Stage 1 at liftoff, burn for ~150 seconds, then separate. HTVE (option d): High Thrust Vikas Engine = 800 kN at 62 bar chamber pressure — used in GSLV second stage, not strap-ons. Vikas-X (option b): LVM3 core, not GSLV strap-ons.
Q10. What was the key milestone achieved during Kaveri's high-altitude tests in Russia (Oct 2022 and Feb 2023)?
- (a) Kaveri achieved its full target wet thrust of 81 kN for the first time — qualifying for immediate integration with LCA Tejas operational squadrons
- (b) The Dry Kaveri variant achieved 48.5 kN dry thrust — surpassing its simulated target of 46 kN — on board an Il-76 testbed at Gromov Flight Research Institute, validating the engine for the Ghatak UCAV application ✅
- (c) India became the first country to test a domestic jet engine on a Russian military aircraft, triggering MTCR compliance concerns
- (d) Kaveri's afterburner was successfully tested at hypersonic speed for the first time, achieving Mach 2.5 in level flight
✅ (b). October 2022 and February 2023: High-altitude tests at Gromov Flight Research Institute, Russia (a world-class aero-engine test facility). The Dry Kaveri (non-afterburning variant) was mounted on an Ilyushin Il-76 testbed aircraft, replacing one of its four engines. At simulated altitude conditions (~13,000 m), the Dry Kaveri achieved 48.5 kN dry thrust — exceeding the simulated target of 46 kN. This was significant because: (1) High-altitude testing is critical — engines behave differently in thin air. (2) 48.5 kN exceeds the previous ground-test baseline of 46 kN. (3) This achievement confirmed the Dry Kaveri's suitability for the DRDO Ghatak UCAV (which flies at altitude, doesn't need afterburner). Initial Flight Release (IFR) certification was expected by 2024 following these tests. The tests did NOT achieve the full 81 kN wet target (option a wrong) — that remains the goal of Kaveri 2.0. As of May 2025, testing continues on the Russian Il-76 testbed with only 25 hours of testing remaining.
⚡ Quick Revision — Vikas & Kaveri Complete Summary
| Topic | Exam-Ready Facts |
|---|---|
| Vikas — Name | Named after Dr. Vikram Ambalal Sarabhai (ISRO founder). Developed at LPSC. French Viking engine technology (SEP, 1974). Fully indigenised. First test: 1985. |
| Vikas — Propellant | UDMH (fuel) + N₂O₄ (oxidiser). EARTH-STORABLE. HYPERGOLIC (self-igniting — no igniter needed). NOT cryogenic. UH 25 = 75% UDMH + 25% hydrazine (newer variants). |
| Vikas — Specs | Thrust: 799 kN (standard) / 800 kN (HTVE). ISP: ~293s. Propellant: 40t (PSLV/GSLV) / 55t (LVM3 — 2 engines = 1,598 kN). |
| Vikas — Used In | PSLV Stage 2 (PS2), GSLV Stage 2 (GS2) + 4 strap-ons, LVM3 L110 core. Every ISRO liquid-stage rocket. |
| Vikas — 2023 Milestone | Jan 2023: First throttling test — 67% thrust for 43 seconds. Critical for Gaganyaan human rating. TV-D1 abort mission uses Vikas variant. |
| Kaveri — Developer | GTRE (Gas Turbine Research Establishment), Bengaluru — DRDO lab. Programme started 1986. Afterburning turbofan (aircraft engine, not rocket). |
| Kaveri — Key Failure | Target: 81 kN wet. Achieved: 70.5 kN wet, 46 kN dry. Delinked from Tejas: September 2008. Tejas uses GE F404 (Mk1/1A), GE F414 (Mk2). Cost: ₹2,839 crore. |
| Kaveri — Current Status | Dry Kaveri (49–51 kN, no afterburner) → Ghatak UCAV. Oct 2022-Feb 2023: 48.5 kN in Russia tests. Godrej Aerospace: 8 modules contract (private sector, ₹500 cr). GTRE aims Ghatak integration by 2026. |
| Kaveri — 2024–26 News | Jan 2024: afterburner work begins. Jun 2024: Safran audit clears for integration. Nov 2024: BrahMos Aerospace 29 kN afterburner for Kaveri 2.0. Dec 2024: Dry Kaveri approved for Il-76 flight tests. May 2025: Approved for LCA-Tejas manned testing. Sep 2025: DRDO DG confirms Tejas testing imminent. |
| Kaveri 2.0 | Dry Kaveri + BrahMos 29 kN afterburner = 83–85 kN wet thrust. Certification by ~2032. Potential F404 alternative for Tejas Mk1A. |
| Kaveri Lesson | DRDO Chairman: "Never develop engine and platform simultaneously." AMCA engine (120 kN, Safran collaboration with India IP) starting before AMCA airframe — applying Kaveri lesson. |
| Kaveri Spin-offs | KADECU (indigenous FADEC by DARE). Kaveri Marine Gas Turbine (BHEL-GTRE, Sep 2024). Military turbocharger for armoured vehicles. Metallurgy and turbine design knowledge for AMCA. |
🚨 5 UPSC Traps — Vikas & Kaveri:
Trap 1 — "Vikas is a cryogenic engine" → WRONG! Vikas uses UDMH + N₂O₄ — earth-storable liquids at room temperature. Cryogenic engines are CE-7.5 (GSLV, LH₂+LOX) and CE-20 (LVM3, LH₂+LOX). Vikas = hypergolic earth-storable liquid bipropellant. Completely different from cryogenic.
Trap 2 — "Kaveri is an ISRO rocket engine" → WRONG! Kaveri is a DRDO/GTRE aircraft jet engine (afterburning turbofan) for the LCA Tejas/Ghatak UCAV. It uses atmospheric oxygen — it CANNOT work in space. Vikas is ISRO's rocket engine. Two entirely different engines by two different organisations.
Trap 3 — "Kaveri successfully powered the Tejas fighter" → WRONG! Kaveri was officially delinked from Tejas in September 2008. Tejas currently uses the American GE F404 engine. Kaveri 2.0 (with afterburner) aims to eventually power Tejas — but as of 2026 it's still under development and testing.
Trap 4 — "The Vikas Engine has no connection to France" → WRONG! Vikas was directly inspired by and based on the French Viking engine — technology licensed from Société Européenne de Propulsion (SEP) in 1974. Later fully indigenised. HAL signed a fresh MoU with Safran (SEP's successor) in 2023 — but for AMCA engine, not Vikas.
Trap 5 — "Kaveri programme was a total failure" → WRONG! While Kaveri failed to power Tejas, it gave India: indigenous turbine design capability, KADECU (FADEC system), Kaveri Marine Gas Turbine, military turbocharger, 3,217 hours of jet engine testing experience, metallurgy knowledge. Dry Kaveri is now targeting Ghatak UCAV. The knowledge is foundational for India's AMCA engine programme.
Trap 1 — "Vikas is a cryogenic engine" → WRONG! Vikas uses UDMH + N₂O₄ — earth-storable liquids at room temperature. Cryogenic engines are CE-7.5 (GSLV, LH₂+LOX) and CE-20 (LVM3, LH₂+LOX). Vikas = hypergolic earth-storable liquid bipropellant. Completely different from cryogenic.
Trap 2 — "Kaveri is an ISRO rocket engine" → WRONG! Kaveri is a DRDO/GTRE aircraft jet engine (afterburning turbofan) for the LCA Tejas/Ghatak UCAV. It uses atmospheric oxygen — it CANNOT work in space. Vikas is ISRO's rocket engine. Two entirely different engines by two different organisations.
Trap 3 — "Kaveri successfully powered the Tejas fighter" → WRONG! Kaveri was officially delinked from Tejas in September 2008. Tejas currently uses the American GE F404 engine. Kaveri 2.0 (with afterburner) aims to eventually power Tejas — but as of 2026 it's still under development and testing.
Trap 4 — "The Vikas Engine has no connection to France" → WRONG! Vikas was directly inspired by and based on the French Viking engine — technology licensed from Société Européenne de Propulsion (SEP) in 1974. Later fully indigenised. HAL signed a fresh MoU with Safran (SEP's successor) in 2023 — but for AMCA engine, not Vikas.
Trap 5 — "Kaveri programme was a total failure" → WRONG! While Kaveri failed to power Tejas, it gave India: indigenous turbine design capability, KADECU (FADEC system), Kaveri Marine Gas Turbine, military turbocharger, 3,217 hours of jet engine testing experience, metallurgy knowledge. Dry Kaveri is now targeting Ghatak UCAV. The knowledge is foundational for India's AMCA engine programme.
