The head of a major Chinese space developer presented a design for a rocket that looks like a smaller copy of SpaceX's Starship system. I figured out how the Chinese are repeating Elon Musk's rocket - and what are the fundamental differences. China presented to the public a project of a reusable space transportation system similar to Elon Musk's Starship. The concept was presented at the International Symposium on Prospects and Cooperation in Manned Space Flight to Low Earth Orbit, held on February 17 in Beijing.

Starship is SpaceX's next-generation super-heavy rocket, prototypes of which are currently being tested in Texas. According to the plans, it will be able to deliver about 100 tons of cargo to low earth orbit. The design of this rocket provides for the possibility of multiple reuse of both stages, which should lead to a serious reduction in launch costs. Both stages will land on their tails similar to the Falcon 9 boosters, while as the Starship upper stage descends from orbit, heat shield tiles and large aerodynamic rudders have been installed on it.

The Chinese project was demonstrated by Wang Xiaojun, president of the China Academy of Space Technology, the country's main rocket manufacturer. The presented concept largely repeats Starship. The profile of its upper stage is almost identical to Musk's rocket: two pairs of aerodynamic rudders are visible on the slides of the presentation, large at the bottom, small at the top. The flight profile also looks similar, the descent will go sideways for air braking, after which, when approaching the ground, the rocket will turn its engines down and sit down.

The lower stage of the Chinese-designed rocket differs from Starship much more, and is more similar to the first stage of Blue Origin's New Glenn. Unlike the Musk project, instead of top-mounted lattice rudders, it uses traditional "wings" located at the top and bottom. Grid and regular rudders show optimal performance in different flight modes, but, in general, perform the same tasks.

However, the main difference between the Chinese project and the American one is the scale. The rocket, demonstrated at the symposium, will have to deliver only 20 tons to low Earth orbit.

This translates it into a different class of carriers, but reduces the mass and complexity of the system.

Despite the fact that the proposed Chinese rocket also uses a methane-oxygen fuel pair, the engines of the two transport systems are fundamentally different. The American Raptor engine operates in a closed circuit with full gasification of components. This means that its fuel pumps are powered by two gas generators, one of which burns a lot of fuel in a small amount of oxidizer, and the other vice versa. First, the gas from both generators enters two independent pump turbines, and from them into the main combustion chamber, where both components ignite and create jet thrust. This scheme allows you to achieve high working pressure and efficiency.

The Chinese rocket uses open-cycle engines, where the gas from the generator is simply thrown into the atmosphere and is used only to power the turbines of the pumps.

This design is simple, reliable and has been used since the pioneers of the space industry, but is ineffective. At the presentation, it was noted that the presented design is under development and can change a lot. The Chinese also did not name the approximate timing of the launch of the rocket. In April 2021, the Chinese Academy of Space Technology already showed a video with a Starship-like rocket, but it had very few details, and the presentation was not led by the head of the academy.

President Wang said that the new rocket is being developed for flights to low Earth orbit and for transporting cargo between two points on Earth. This also distinguishes it from Starship, whose main stated mission is to fly to Mars and the Moon.

In recent years, Chinese developers have been actively showing interest in reusable space systems. Recently, Space Transportation presented a project for a hypersonic suborbital liner that would allow flying between continents in less than an hour.

bbabo.Net