Expanding fleet

The Chinese space sector's most recent accomplishment came on Tuesday, when the newest carrier rocket－the Long March 8－made its maiden flight from Wenchang.

The 50-meter, medium-lift rocket transported five experimental satellites into a sun-synchronous orbit at an altitude of 512 km.

Designed and built by the China Academy of Launch Vehicle Technology, the rocket is tasked with meeting surging demand for launch services from commercial satellite companies at home and abroad.

Xiao Yun, the rocket's project manager, said the successful maiden flight was a new achievement in China's efforts to upgrade its medium-lift launch vehicle system, and will push forward the nation's efforts to become a world-class space power.

The rocket's services will also give a strong boost to the development and deployment of satellites operating in low-and medium-altitude orbits, he said.

The vehicle has two core stages and two side boosters. Its six engines are propelled by liquid oxygen, liquid hydrogen and kerosene.

With a liftoff weight of 356 tons, it is capable of sending 4.5-ton payloads into a sun-synchronous orbit 700 km above Earth, or satellites with a combined weight of 2.8 tons into a geostationary transfer orbit, the academy said.

Project managers have estimated that at least 10 Long March 8s will be used every year, given the robust demand from domestic and international satellite companies, while annual manufacturing capacity will soon reach 20.

To improve the rocket's competitiveness, it is expected to eventually become the first reusable Long March model.

The designers intend to develop an integrated first stage for a reusable variant, consisting of a core booster and two side boosters.

Instead of breaking up and falling back to Earth like similar stages of previous Chinese rockets, the new core and side boosters will stay together and make powered landings on a recovery platform at sea.

About eight months ago, also in Wenchang, the Long March 5B heavy-lift carrier rocket undertook its maiden mission, transporting a prototype of China's new-generation manned spacecraft into a low-Earth orbit.

The rocket is 53.7 meters long, with a core-stage diameter of 5 meters, and has a liftoff weight of 849 tons. It is the most powerful Chinese rocket in terms of carrying capacity for low-Earth orbit.

The Long March 5B is central to the nation's space station program as it is the only Chinese launch vehicle capable of carrying large space station parts into orbit.

In the next two years, three Long March 5B flights will put major components of China's space station into orbit for assembly.

The multimodule station, Tiangong or Heavenly Palace, will have three sections－a core module and two space labs－with a combined weight of more than 90 tons.

It is expected to become fully operational before the end of 2022 and to operate for about 15 years.

Meanwhile, the new-generation manned spaceship has two main sections－the reentry and service modules. Tasked with serving the space station program, it employs world-class designs and technologies, and features great reliability and flexibility, multiple functions and reusability.

The craft is 8.8 meters long, has a diameter of 4.5 meters, and a liftoff weight of 21.6 tons.

The reentry module will house the crew and control the craft during spaceflight, while the service module will contain the power and propulsion systems.

Designers at the China Academy of Space Technology said that compared with the Shenzhou series, the country's operational crewed spacecraft family, the new model is capable of longer missions, housing more astronauts and cargo and operating in tougher environments.