A view of the reusable liquid rocket engine developed by China's Xi'an Aerospace Propulsion Institute. (PHOTO: Xi'an Aerospace Propulsion Institute)

By Tang Zhexiao

China's aerospace technology researchers recently announced a test flight of a reusable rocket engine, signaling that engine reusability technology in the country has reached the stage of practical use.

As a new generation launch vehicle, the liquid oxygen and kerosene rocket engine can be used for vertical take-off and landing, and is similar to those used by SpaceX on its Falcon 9 rockets.

Liquid oxygen and kerosene rocket engines can provide the main power for space flights. Carrying their own oxygen, they can function either in the air or a vacuum.

Using the advanced high-pressure supplementary combustion cycle system, the engines' thrust can be more than 60 percent higher than the existing "Long March" series of launch vehicle engines, and its carrying capacity is about three times that of the original.

Despite the advantage on thrust, the engines' fuel is non-toxic and only causes small amounts of pollution.

Technical challenges of the engines, such as repeat ignition technology, large-scale continuous thrust adjustment and thermal protection technology, have been overcomed by researchers.

More attention will be paid to the high reliability, low cost and high performance of the engines in the future, according to the research team.