Isro successfully fires engine that will power India’s heaviest launch vehicle
India’s space ambitions received a significant boost as the Indian Space Research Organisation (Isro) successfully conducted the first major hot test of the Lox Kerosene 200T thrust semi-cryogenic engine.
The test, carried out at the Isro Propulsion Complex (IPRC) in Mahendragiri, Tamil Nadu, marks a major step forward in developing a more powerful and efficient engine for future space missions.
The semi-cryogenic engine, powered by a combination of Liquid Oxygen (LOX) and Kerosene, delivers a high thrust of 2000 kN. It is designed to enhance the payload capacity of India’s LVM3 rocket and strengthen the country’s capabilities in space launch vehicles. The successful test of the engine’s Power Head Test Article (PHTA) demonstrates Isro’s progress in advancing space propulsion technology and its commitment to innovation in rocket development.
Following the test, Union Minister Dr. Jitendra Singh hailed the achievement, stating that Isro had reached another milestone in strengthening its space mission capabilities. The test was conducted at a newly established facility, which was dedicated to the nation by Prime Minister Narendra Modi during his visit to Thiruvananthapuram.
The Liquid Propulsion Systems Centre (LPSC) is leading the development of the semi-cryogenic engine and stage. The new SC120 stage, powered by the SE2000 semi-cryogenic engine, is set to replace the existing L110 core liquid stage of the LVM3 rocket.
This upgrade is expected to increase the rocket’s payload capacity from four tonnes to five tonnes in geostationary transfer orbit (GTO). The semi-cryogenic propulsion system uses non-toxic and non-hazardous propellants, offering better performance compared to existing liquid propulsion stages.
Key subsystems of the SE2000 engine include the thrust chamber, pre-burner, turbo pump system, control components, and startup system. The engine operates on an oxidizer-rich staged combustion cycle, a complex but highly efficient design that allows for a high chamber pressure of 180 bar and a specific impulse of 335 seconds. Given its advanced technology, semi-cryogenic engines of this scale are available only in a few nations worldwide.
To support this development, Isro established the Semicryogenic Integrated Engine Test Facility (SIET) at IPRC, Mahendragiri. This state-of-the-art facility, inaugurated in February 2024, enables testing of semi-cryogenic engines with thrust levels up to 2600 kN. Equipped with a sophisticated control system and high-precision data acquisition capabilities, the facility is crucial for validating engine performance.
Before the full integration of the SE2000 engine, Isro conducted a series of performance evaluation tests on intermediate configurations, including the PHTA.
The recently conducted hot test was part of this process, validating critical subsystems such as the pre-burner, turbo pumps, start system, and control components. The ignition process was meticulously developed through multiple trials using a separate test article, the Pre-Burner Ignition Test Article (PITA), ensuring a smooth and controlled start-up sequence.
The successful test lasted 2.5 seconds, demonstrating the smooth ignition and operation of the engine. All critical parameters performed as expected, marking a major breakthrough in the semi-cryogenic engine development program. Moving forward, Isro plans to conduct a series of additional tests on the PHTA before proceeding with the full integration of the SE2000 engine.
