In May 2019, the Kyushu Yunjian "Lingyun" 10-ton deep variable thrust liquid oxygen methane engine completed the engine assembly and test process, and is about to undergo a hot test run of the whole machine.

"Lingyun" liquid oxygen methane engine is a commercial liquid rocket engine with multiple start capabilities, 30% to 100% deep variable thrust capability, and convenient use and maintenance. The service targets include the ground stage of small liquid rockets and the upper stage of medium liquid rockets.
A technical prerequisite for liquid rockets to be widely used in the commercial aerospace market is that liquid rockets can be recovered and reused. Through recovery and reuse, the cost of a single launch can be significantly reduced and commercial applications can be realized. The technical basis for the recovery and reuse of liquid rockets comes from the three key technologies of engine reusability, multiple starts, and deep variable thrust.
After the whole machine is commissioned, the "Lingyun" engine will continue to undergo reliability assessment tests in the next stage, and at the same time the 80t (vacuum thrust) liquid oxygen methane engine "Longyun" with greater thrust and a reusable and recycling technology verification platform "Lingxiao" has completed the program demonstration and will start more in-depth research and development work.