MAHENDRAGIRI, October 20 — The Indian Space Research Organisation (ISRO) successfully accomplished a 720-second flight-acceptance hot-fire test of the human-rated CE-20 cryogenic upper-stage engine for the Gaganyaan mission at the ISRO Propulsion Complex (IPRC) in Mahendragiri, Tamil Nadu on Monday.
Operated at an uprated vacuum thrust level of 22 tonnes (218 kN), the high-thrust engine burned cryogenic propellants—Liquid Oxygen (LOX) at -183°C and Liquid Hydrogen (LH2) at -253°C—throughout the full simulated mission flight profile. Telemetry verified optimal combustion chamber pressures, regenerative cooling dynamics, and structural margins under extreme thermal gradients, confirming zero anomalous vibration harmonics.
ISRO confirmed that the test successfully completes the mandatory human-rating ground test certification matrix for the C25 stage of the Launch Vehicle Mark-3 (LVM3), paving the way for the inaugural uncrewed orbital demonstration mission (G1) carrying the Vyommitra humanoid robot.
The thermodynamic physics of cryogenic rocket engines (staged combustion vs gas-generator cycles), the structural payload capacity of LVM3 (4,000 kg to GTO, 8,000 kg to LEO), and mission architecture of the Gaganyaan Human Spaceflight Programme are essential study topics for UPSC GS-III (Space Technology).