China’s Chi Engine Demonstrates Oxygen-Rich, Reusable Deep-Space Propulsion

Chinese private Mega Engine tested its Chi oxygen-rich closed-cycle kerosene-LOX engine for 1,000 seconds across multiple long-duration tests, showing rapid startup, stable operation, restart capability, and thrust from roughly 35–75 tons at sea level (about 87 tons in vacuum); the engine is designed for high-altitude propulsion on medium/large rockets and supports a plan for a more powerful 200-ton Yan engine for heavy-lift applications.