New Delhi: ISRO Semi-Cryogenic Engine development reached another major milestone after the Indian Space Research Organisation (ISRO) successfully conducted a hot test of the Semi-Cryogenic Engine Power Head Test Article (PHTA) at a 175-tonne thrust level. The successful test brings India one step closer to developing a more powerful and efficient rocket engine for future LVM3 missions and advanced space exploration.
Details of ISRO Semi-Cryogenic Engine Test
ISRO carried out the hot test on June 24, 2026, at the ISRO Propulsion Complex (IPRC), Mahendragiri, Tamil Nadu.
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The test was officially announced on June 27, 2026. It was the eighth hot test using the Power Head Test Article (PHTA), which includes all major engine systems except the thrust chamber.
What is the Objective of ISRO Semi-Cryogenic Engine Test
The main objective of this test was to:
- Study engine build-up after pre-burner ignition.
- Demonstrate stable engine operation at a much higher thrust level.
- Validate the performance of key engine systems before full engine testing.
During the test, ISRO successfully operated the engine at 175 tonnes of thrust (88% of its full capacity) for the first time.
The engine’s main turbopumps also worked as expected by delivering outlet pressures of 400 bar and 500 bar.
A Big Improvement Over Earlier Tests
Earlier PHTA hot tests were conducted at:
- 94 tonnes (47% thrust)
- 120 tonnes (60% thrust)
The latest successful test at 175 tonnes marks a significant jump in engine capability and gives ISRO confidence to move towards testing the engine at its full 200-tonne (100%) thrust level.
Why Is the Semi-Cryogenic Engine Important
The new SC120 Semi-Cryogenic Propulsion Stage, powered by the SE2000 engine, is being developed to replace the existing L110 core stage of the LVM3 launch vehicle. Once introduced, the new propulsion system is expected to:
- Increase the payload capacity of LVM3.
- Improve launch efficiency.
- Use cleaner and non-toxic propellants such as Liquid Oxygen (LOX) and purified kerosene (Isrosene).
- Support future heavy-lift and deep-space missions.
Why This Achievement Matters
The successful hot test is an important milestone in India’s indigenous rocket engine programme. It proves that the engine systems can safely operate at very high thrust levels and brings ISRO closer to qualifying the engine for future launch vehicles.
The development of the Semi-Cryogenic Engine is expected to strengthen India’s ability to launch heavier satellites and support future human spaceflight and planetary exploration missions.
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