What is special about Methalox Rocket Engines?

Methalox engines, which burn Liquid Methane as fuel and Liquid Oxygen (LOX) as the oxidizer, hit the “Goldilocks” zone of rocket propulsion. They offer a near-perfect balance between efficiency, fuel density, and rapid reusability, driving a major shift in the modern aerospace industry.

• Clean Burning (No “Coking”): Traditional rockets use Kerolox (Kerosene and LOX). Kerosene leaves behind sticky soot and carbon deposits (coking) inside the engine’s complex plumbing and turbines as it burns. Methane burns extremely clean, requiring almost no refurbishment between flights—a critical requirement for rapidly reusable rockets.
• Mars Refueling (ISRU -In-Situ Resource Utilization): Methane can be synthesized on Mars using the Sabatier reaction, which combines carbon dioxide from the Martian atmosphere with water from ice to create methane and oxygen. This allows a spacecraft to land on Mars, manufacture its own return fuel, and fly back to Earth.
• The Cryogenic “Sweet Spot”: Liquid Oxygen boils at -183°C and Liquid Methane boils at -161°C. Because their temperatures are so close, they do not need heavy, complex thermal insulation between their tanks. Liquid Hydrogen, by contrast, requires a brutal -253°C, forcing complex engineering. Similar boiling points allow for much lighter tank designs.
• Performance Balance: Hydrolox (Hydrogen) is highly efficient but terribly un-dense, requiring massive, drag-inducing tanks. Kerolox is very dense but less efficient. Methalox sits right in the middle, offering high thrust in a relatively compact package with excellent fuel efficiency (Specific Impulse).

Prominent examples of this technology include SpaceX’s Raptor engine (powering Starship), Blue Origin’s BE-4 (powering Vulcan Centaur and New Glenn), and ISRO’s upcoming methalox engines currently in development.

Upcoming methalox engines currently in development in India

Here is the current landscape of methalox engine development in India:

1. ISRO’s 10-Ton (100 kN) Technology Demonstrator

ISRO began its methalox journey by building and testing a smaller 10-ton (roughly 100 kN) technology demonstrator engine. This served as a critical pathfinder, allowing scientists at the Liquid Propulsion Systems Centre (LPSC) to master the unique cryogenic handling, spark ignition, and stable combustion characteristics of methane before attempting to build a massive heavy-lift engine.

2. ISRO’s Main Project: The LME-1100 (1100 kN Engine)

The primary operational methalox engine currently being developed by ISRO is actually ten times more powerful than the demonstrator: the LME-1100, which is designed to generate 1100 kN (approx. 110 tonnes) of thrust.

• Purpose: This engine will power the upcoming Next Generation Launch Vehicle (NGLV), a partially reusable heavy-lift rocket crucial for India’s future space station and crewed lunar missions.
• Manufacturing: To make it cost-effective and industry-friendly, over 70% of the LME-1100’s components are being built using advanced additive manufacturing (3D printing) in collaboration with Indian industrial partners.
• Latest Testing: ISRO achieved a major milestone on October 9, 2026, successfully conducting the first full-scale hot test of the engine’s Gas Generator at the ISRO Propulsion Complex (IPRC). They have also successfully spin-tested the 3D-printed liquid oxygen pump impeller up to its rated operating speed.

3. Cosmicport’s CRYONIX (100 kN)

In the private sector, the Indian aerospace startup Cosmicport is actively developing its own operational 100 kN-class methalox engine named CRYONIX.

• This gas-generator cycle engine targets a specific impulse of 360 seconds.
• It is being designed specifically to power their planned MACH BLUE reusable launch vehicle, proving that methalox architecture is gaining serious momentum across both the public and private space sectors in India.