China's 110-tonne liquid oxygen kerosene engine, the Liqing-2, completed a long-duration qualification test, marking a key step toward its future role as the main engine for the reusable Lijian-2 rocket, the CAS Space, a leading Chinese commercial space company, announced Tuesday.
The Liqing-2 features a pin nozzle design, incorporating a pin-like protrusion at the center of the engine nozzle. This design allows for precise thrust control through a simple structure, making it highly reliable and an essential technology for reusable rockets. Compared to traditional designs, the Liqing-2 is more cost-effective and lighter, balancing high performance with economic efficiency.
The long duration refers to the rocket engine's ignition time that far exceeds the actual flight requirements, designed to test engine durability under extreme conditions.
In this test, the engine's operating duration was extended to 620 seconds, which is 3.5 folds of the rocket's actual flight time with a single ignition lasting 400 seconds, setting a new record for the longest stable operation of the engine.
"This was a qualification-level test under extreme duration conditions. It is a rigorous assessment for the engine, as it has to endure sustained high temperatures, high rotational speeds, intense heat flux and continuous vibrations throughout. The results demonstrate the engine's overall performance is stable, fully covers flight conditions, and has sufficient service life margin," said Ming Aizhen, deputy general manager of CAS Space's power design department.
The test this time provided in-depth validation of key parameters and operational reliability of the engine, laying a solid foundation for its future engineering and mass production.
"At present, the Lijing-2 has fully entered the critical phase of reliability testing. Subsequent work will advance along five main tracks of qualification testing, three-engine parallel power system testing, rocket integration and matching, mass production, and the rocket's maiden flight. After finalization, the engine will support routine high-frequency rocket launches," said Ming.
So far, Liqing-2's cumulative reliability test time has surpassed 2,000 seconds. The engine is designed to serve as the primary propulsion system for the reusable versions of both the Lijian-2 and its heavy-lift variant.
The Lijian-2 rocket is China's first launch vehicle to adopt the Common Booster Core configuration, a modular rocket design architecture in which the first stage and its side boosters are structurally and functionally identical.
It is capable of carrying up to 8 tonnes to a 500-km sun-synchronous orbit or 12 tonnes to a 200-km low Earth orbit.
On March 30, 2026, the rocket successfully completed its maiden flight, demonstrating the core technologies of China's next-generation space transportation system. During this mission, it accurately deployed the Qingzhou prototype cargo spacecraft and two satellites into the preset orbit.
China's Liqing-2 rocket engine completes long-duration test
