The Indian Space Research Organisation has successfully demonstrated a hot test of the Semi-Cryogenic Engine Power Head Test Article at a thrust level of 175 tons. The test was conducted on 24 June 2026 at the Liquid Propulsion Systems Centre (IPRC) in Mahendragiri, Tamil Nadu.

The Power Head Test Article incorporates all engine systems except the thrust chamber. This was the eighth hot test in the series using the PHTA. The objectives included studying the build-up after pre-burner ignition and demonstrating steady-state operation at higher thrust levels.

Previous PHTA tests were carried out at 94 tons, representing 47 per cent thrust, and 120 tons, representing 60 per cent thrust. In this latest test, the PHTA was operated at 175 tons, equivalent to 88 per cent thrust, for the first time. The test also demonstrated successful operation of the main turbopumps, which delivered outlet pressures of 400 and 500 bar.

The test proceeded exactly as predicted, with all engine parameters performing as expected. This achievement has provided sufficient confidence for the demonstration of steady-state performance of the engine powerhead at the full 200-ton thrust level. It marks a major milestone in the indigenous development of India’s semi-cryogenic engine program.

The Semi-Cryogenic Propulsion Stage, designated SC120, is powered by the 2000 kN-class SE2000 engine. It is being developed to replace the current L110 core stage of the LVM3 launch vehicle. This strategic upgrade is expected to substantially increase payload capacity while enhancing operational efficiency.

The semi-cryogenic system employs cleaner, non-toxic propellants, specifically liquid oxygen and purified kerosene known as isrosene. These propellants offer improved performance compared to conventional propulsion stages. The integration of the semi-cryogenic propulsion system, combined with an uprated cryogenic upper stage, represents a significant advancement in ISRO’s roadmap to enhance the payload capability of the LVM-3.

This achievement builds upon earlier milestones, including the successful hot test of the Engine Power Head Test Article in March 2025 at lower thrust levels. The latest test demonstrates India’s growing expertise in high-thrust semi-cryogenic propulsion technology, a capability possessed by only a handful of nations.

The SC120 stage, once operational, will enable LVM-3 to carry heavier payloads into geosynchronous transfer orbit, increasing capacity from four tons to five tons. This enhancement will strengthen India’s ability to undertake more ambitious missions, including deep space exploration and heavier satellite launches.

The successful test also underscores ISRO’s commitment to self-reliance in advanced propulsion technologies. While India has engaged in international cooperation, including discussions with Russia’s Roscosmos on semi-cryogenic engines, the indigenous SE2000 program is progressing steadily and is now approaching full thrust demonstration.

This milestone places India firmly on track to field a new generation of launch vehicles with greater efficiency, reliability, and payload capacity, reinforcing its position in the global space sector.

ISRO