ISRO Advances Indigenous 1,100 kN Methane Rocket Engine for Next-Generation Launch Vehicle

The Indian Space Research Organisation (ISRO) has successfully completed the first ignition test of the full-scale gas generator for its indigenous 1,100 kilonewton (kN) Liquid Oxygen–Methane (LOX-Methane) rocket engine, marking a significant milestone in the development of advanced propulsion systems for India’s future launch vehicles.

The test was conducted on October 9, 2026, as part of the development programme for the LME1100 engine. ISRO announced the achievement on October 16, highlighting progress in indigenous rocket propulsion, additive manufacturing and advanced cryogenic engineering.

The LME1100 engine is being developed as a propulsion system for India’s Next Generation Launch Vehicle (NGLV). The programme aims to establish reliable, cost-effective and reusable launch capabilities while strengthening India’s technological independence in advanced rocket propulsion.

ISRO also revealed that more than 70% of the engine’s components have been manufactured using additive manufacturing technologies, with extensive participation from Indian industrial partners.

India Develops Advanced LOX-Methane Rocket Propulsion

Liquid oxygen and methane are emerging as an important propellant combination for next-generation rocket engines because of their clean combustion characteristics, reduced maintenance requirements and suitability for reusable launch systems.

Unlike conventional kerosene-based rocket propulsion, methane generally produces less carbon-rich residue during combustion, reducing deposits within engine components. This characteristic is particularly useful for reusable rockets, where engines must withstand repeated operations with limited refurbishment.

Methane also offers advantages for future planetary exploration. Scientists have identified the possibility of producing methane and oxygen using carbon dioxide and water ice available on Mars, creating opportunities for manufacturing propellants beyond Earth.

Recognising these advantages, ISRO has selected LOX-Methane propulsion for its Next Generation Launch Vehicle and future heavy-lift launch systems.

The development forms part of India’s long-term space transportation strategy, including preparations for advanced launch vehicles capable of supporting human spaceflight and future lunar exploration missions.

Successful Ignition Test of Full-Scale Gas Generator

The latest milestone involves the successful ignition of the full-scale gas generator developed for the LME1100 engine.

A gas generator is an important subsystem in certain liquid rocket engines. It burns a controlled quantity of propellants to produce high-energy gases that drive the turbines connected to the engine’s propellant pumps.

These turbopumps deliver liquid oxygen and methane to the combustion chamber at the required pressures and flow rates, enabling the engine to generate thrust.

The LME1100 employs a Gas Generator Cycle (GGC), with its design optimised for manufacturing efficiency, cost-effectiveness and participation by Indian industry.

According to ISRO, the full-scale gas generator was manufactured using additive manufacturing techniques and is undergoing qualification testing at the ISRO Propulsion Complex (IPRC).

Before conducting the full-scale ignition trial, engineers extensively tested a smaller gas generator to establish the ignition sequence and evaluate the performance of its additively manufactured injector elements.

The successful October 9 ignition represents progress in validating the design and operating characteristics of this critical engine subsystem. ISRO plans additional tests under different operating conditions to assess its performance and reliability.

Over 70% of LME1100 Components Manufactured Using 3D Printing

One of the most significant features of the LME1100 programme is the extensive use of additive manufacturing, commonly known as 3D printing, in producing complex rocket engine components.

ISRO confirmed that more than 70% of the engine’s components have been manufactured through additive manufacturing processes with the involvement of industrial partners across India.

Unlike conventional manufacturing, which often involves removing material from larger metal blocks, additive manufacturing builds components through successive layers of material.

This approach allows engineers to manufacture complex internal geometries, reduce the number of separate components and develop intricate cooling channels and fluid passages that may be difficult to produce using traditional methods.

Additive manufacturing can also reduce material wastage and simplify production processes, making it particularly valuable for advanced aerospace propulsion systems.

The successful production of critical LME1100 components demonstrates the growing capabilities of India’s domestic aerospace manufacturing ecosystem and its ability to support sophisticated rocket engine development.

Indigenous Turbopumps Undergo Critical Development Tests

The LME1100 programme includes the development of specialised turbopumps for liquid oxygen and methane, which must operate under demanding mechanical and thermal conditions.

These pumps are responsible for delivering propellants to the engine’s combustion chamber at precisely controlled pressures and flow rates.

According to ISRO, Indian industries have manufactured several components for the liquid oxygen and methane turbopump systems. These include pump hardware, dynamic sealing systems and specialised bearings.

The 3D-printed liquid oxygen pump impeller has successfully undergone spin testing up to its rated operating speed at the Liquid Propulsion Systems Centre (LPSC).

Engineers are also conducting qualification tests on turbopump bearings and sealing systems at LPSC and IPRC.

Cold-flow characterisation of the integrated turbopump systems is underway at IPRC. These tests evaluate fluid movement and component behaviour before the engine undergoes complete integrated firing trials.

The progress demonstrates India’s growing expertise in manufacturing high-performance rotating machinery and precision components required for advanced rocket propulsion.

ISRO Validates Advanced Ignition Technologies

Reliable ignition is essential for liquid rocket engines because propellants must ignite in a controlled sequence to establish stable combustion.

As part of the LME1100 development programme, ISRO has successfully tested both oxidiser-rich and fuel-rich spark-torch ignition systems.

These igniters use controlled combustion to generate a flame capable of initiating combustion in the engine’s larger propulsion system.

Engineers have also developed an alternative ignition system employing a semiconductor-based spark plug.

This technology was developed through collaboration between LPSC, the Vikram Sarabhai Space Centre (VSSC) and the Indian Institute of Space Science and Technology (IIST).

In another development, LPSC successfully demonstrated a laser-based ignition system using gaseous oxygen with gaseous hydrogen and gaseous methane propellant combinations.

The development of multiple ignition technologies provides valuable engineering experience and supports further improvements in the reliability of indigenous rocket propulsion systems.

LME1100 Builds on Earlier 20-Tonne Methane Engine Research

ISRO’s work on methane propulsion began in 2019, when engineers initiated studies to understand the behaviour of liquid oxygen and liquid methane in rocket engines.

During 2019–2020, the organisation developed and tested a 20-tonne-thrust technology demonstrator designated LM20-TD.

The demonstrator incorporated modified subsystems from ISRO’s existing CE-20 cryogenic engine, including changes to propellant flow control and engine startup arrangements.

The LM20-TD operated using a gas generator cycle and incorporated critical components such as turbopumps, a thrust chamber, ignition systems and propellant flow-control equipment.

ISRO modified its existing cryogenic engine testing infrastructure at IPRC to support the programme.

Engineers successfully completed one cold-flow test and five hot-firing tests, generating valuable information about engine startup, propellant cooling, combustion behaviour and turbopump performance.

The data obtained from these trials provided the technical foundation for designing the larger LME1100 engine.

In 2023, ISRO formally initiated development of the 1,100 kN engine, concentrating on the gas generator, turbopumps, igniter and thrust chamber.

Next-Generation Launch Vehicle to Use Methane Propulsion

The LME1100 engine is intended to support India’s Next Generation Launch Vehicle, representing an important evolution in the country’s rocket development programme.

ISRO is developing NGLV to meet future requirements for launching heavier payloads while incorporating technologies that support greater operational efficiency and reusability.

Methane propulsion offers advantages for reusable launch systems because cleaner combustion can reduce maintenance requirements between missions.

The engine’s design also incorporates considerations for industrial manufacturing and cost-effective production.

According to ISRO, the integrated LME1100 engine is targeted for completion by mid-2027, after which it will undergo extensive hot-firing trials.

These tests will evaluate the engine under prescribed operating conditions, including different thrust-throttling profiles.

Throttling capability is particularly relevant to advanced launch systems because it allows rocket engines to adjust thrust according to different phases of flight.

The successful development of LME1100 will provide India with an indigenous propulsion technology foundation for future launch vehicle applications.

ISRO Completes Design of More Powerful 2,400 kN Methane Engine

Alongside the LME1100 programme, ISRO has completed design activities for a significantly more powerful 2,400 kN LOX-Methane engine.

Unlike the LME1100, which uses a gas generator cycle, the larger engine is being designed around a Full-Flow Staged Combustion Cycle (FFSCC).

In this advanced propulsion architecture, the fuel and oxidiser pass through separate preburner and turbine arrangements before entering the main combustion chamber.

The design allows the propellants to contribute to turbine operation while supporting highly efficient combustion within the engine.

Full-flow staged combustion is among the more technologically demanding liquid rocket propulsion architectures because it requires precise control of high-pressure turbomachinery, combustion processes and thermal conditions.

ISRO intends to use the proposed 2,400 kN engine in future heavy-lift launch vehicles capable of supporting India’s human lunar exploration ambitions.

The development is particularly relevant to India’s objective of conducting a crewed lunar landing mission by 2040, which will require advanced launch capabilities and substantially greater payload transportation capacity.

Indian Industries Strengthen Indigenous Rocket Engine Manufacturing

The LME1100 programme highlights the increasing participation of Indian companies in the development and manufacture of sophisticated space propulsion technologies.

ISRO has involved industrial partners in producing additively manufactured engine components, turbopump systems, specialised bearings, sealing equipment and other critical hardware.

Such collaboration allows Indian industries to acquire expertise in precision manufacturing, advanced materials, high-performance mechanical systems and aerospace production technologies.

The experience gained through these activities can support future launch vehicle programmes while strengthening India’s domestic aerospace supply chains.

The extensive use of additive manufacturing also demonstrates how advanced production technologies are becoming an integral part of India’s space programme.

By combining the research capabilities of ISRO centres with the manufacturing expertise of domestic industry, India is building a broader technological foundation for developing next-generation propulsion systems.

India’s Rocket Propulsion Capabilities Enter a New Phase

ISRO’s successful full-scale gas generator ignition test represents a major developmental milestone in India’s indigenous LOX-Methane propulsion programme.

The progress builds upon decades of experience in liquid propulsion, from the Vikas engine and indigenous cryogenic propulsion systems to the advanced engines now being developed for future launch vehicles.

The LME1100 programme combines methane-based propulsion, additive manufacturing, indigenous turbomachinery and advanced ignition technologies within a coordinated national development effort.

With the integrated 1,100 kN engine targeted for completion in 2027 and design work completed for the more powerful 2,400 kN engine, India is advancing towards a new generation of launch propulsion systems.

These developments will strengthen the country’s capabilities in reusable launch technologies, advanced aerospace manufacturing and future heavy-lift missions, supporting India’s long-term ambitions in space exploration and human lunar missions.

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References

1. Indian Space Research Organisation (ISRO), Department of Space — October 16, 2026: Development of LOX-Methane Engine in ISRO — Official Technical Announcement
2. ISRO — Liquid Propulsion Systems Centre (LPSC): Official Centre Information
3. ISRO — ISRO Propulsion Complex (IPRC): Official Centre Information
4. ISRO — Next Generation Launch Vehicle and Future Launch Systems: Indian Space Research Organisation

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