This year January 19th, the SpaceX Crew Dragon spacecraft successfully tested its abort system, which is due to make its first manned flight in a few months. Another American company, Boeing, also plans to launch it manned vehicle Boeing Starliner during this year, although the tests that they carried out in December 2019 were far from ideal: the ship could not dock with the ISS as it was planned due to a malfunction of the flight time calculation system. Nevertheless, the success of American companies inevitably proves that the monopoly of the Russian Roscosmos on launching people to the ISS is coming to an end.
But even today, Russia is not the only country that has the technology to send people into space. In 2003, the People’s Republic of China launched the first taikonaut into orbit and became the third world space power with its own manned fleet. China still retains its expertise in this area, unlike the United States, where NASA decommissioned the manned space shuttle transportation system in 2011.
The current article highlights the current state of the Chinese manned program, as well as its comparison with the similar programs in Russia, and reasons why the United States and other countries do not consider China as an alternative to the Russian Soyuz ships.
The main space manned program in China is the Shenzhou project (Chinese: 神舟, literally: Divine Ship), formerly referred to as Project 921. The spacecraft started in 1992 by the China Academy of Space Technology (中国空间技术研究院, CAST) and other scientific entities of the China Space Industry Corporation (中国航天工业总公司). In 2003, Chinese manned flight Shenzhou-5 carried on board the first taikonaut Yang Liwei (杨利伟). The Chinese government has kept the launch date of Shenzhou-5 in secret and officially announced it only after the ship landed.
The similarities between the Chinese Shenzhou and the Russian Soyuz are obvious: both ships have three main modules: orbital module (轨道舱), reentry module (返回舱) in the middle, and service module (推进舱). The landing technology of the reentry module has many similar elements with the Russian counterpart: first the brake parachute is used, and then the landing parachute. While landing, the soft landing engine is turned on. Regarding life support systems, China has officially announced that Shenzhou uses a full copy of the Soyuz spacecraft system. Taikonaut spacesuits are also almost indistinguishable from cosmonauts’ spacesuits: the outer layer is made of white nylon, the upper part of the spacesuits is identical, although the life support and pressure systems in the lower part of the Chinese spacesuits have been improved compared to the original Russian versions.
All these similarities are not surprising, because China implemented its space program in a close cooperation with Russia. After the collapse of the USSR, relations between the two countries recovered once again, and space cooperation resumed: Chinese specialists started visiting Russia for studying, and Chinese companies began to purchase Russian equipment. Particularly, in 1994, China acquired the Soyuz spacecraft, a docking unit, a gamma-ray altimeter, a spacesuit, a life support system, and other units. Soviet engineers developed all these elements in the USSR in the early 50s and used for the production of Soyuz spacecraft. Despite the fact that no documentation was provided, the Chinese managed to develop their own structural elements of the future Shenzhou ship on the basis of the purchased equipment.
Yet Shenzhou has its own characteristic differences in the design and functionality. First of all, the orbital module is capable of working independently. In order to achieve this, the Chinese engineers equipped the module with its own propulsion systems (4 propulsion systems with 4 nozzles each), control systems, and two triangular solar panels, each can provide power consumption of over 0.5 kW. Shenzhou’s orbital module can be left in orbit for re-docking with another spacecraft. This cannot be done on the Soyuz spacecraft, since its only hatch – which separates the forward orbital module from the reentry module – is the part of the reentry module,. That is why when the compartments are separated, the orbital module is depressurized. Basically the Shenzhou orbital module can be left on orbit to serve as a satellite.
Also in terms of dimensions, Shenzhou is 13% bigger than Soyuz. This should allow to accommodate up to four crew members on board instead of three (like on the Soyuz ship). However, in fact the Shenzhou’s life support systems are designed only for three crew members. That is why there are usually no more than 2 or 3 taikonauts participating the launch. During the last launch in 2016, there were only two crew members, because they needed to conduct an experiment on increasing the time for taikonauts to stay on orbit).
On the Soyuz spacecraft, all three compartments are wrapped with a heat-insulating layer, while at Shenzhou there are only the orbital module and the service module being covered with a heat-insulating layer, while the reentry module is equipped with a heater instead of a heat-insulating layer. The way solar panels are opened in two ships is also different. Although the diameter of Soyuz is only 10 cm smaller than at Shenzhou, the fairing diameter for the Chinese ship is more than half a meter. The Shenzhou service module has an external communication connection only with the reentry module, while on the Soyuz spacecraft the external communications of all three compartments are interconnected.
The controlled descent system with a backup ballistic descent system was integrated into Shenzhou, the same as it was with the Soyuz ships. The deviation of Shenzhou from the landing site, on average, is 6-24 km, while for the Soyuz-TM ship it was about 35 km, for Soyuz-MS it is up to 20 km (however, it is expected that with the introduction of the new digital descent control system, the landing radius of Soyuz-MS will decrease).
Shenzhou is assembled, tested and transported in an upright position, while Soyuz is tested in an upright position, and is assembled and transported in a horizontal position. The fairing for Shenzhou, like that of the satellite, is assembled in two parts with a vertically standing ship, while the Soyuz, being in a horizontal position, is “inserted” into the completed fairing.
Differences in design are primarily explained by the different purpose of these spacecraft. Initially, the Soyuz spacecraft was designed as a command module for the ship, which was supposed to land on the moon. It was planned that the Soyuz spacecraft will dock in orbit with the module of another spacecraft (Soyuz 7K-LOK), which was then supposed to fly to the moon. Thus, the orbital module of the Soyuz spacecraft would serve only as a transitional gateway when the Soyuz docked with the lunar module. China, while not possessing a large orbital station at that time, created the Shenzhou spacecraft for conducting scientific experiments, as well as for developing space weapons. From an economic point of view, Shenzhou was designed to independently carry out scientific and military tasks, and the orbital module, apart from being a transition module while docking with other spacecraft, was aimed at conducting scientific experiments. The capacity of the re-entry module is also greater than that of Soyuz – in order to accommodate instruments and samples for experiments.
In just 20 years of the existence of the Shenzhou spacecraft, 11 launches were completed, six of which were manned launches involving 14 taikonauts. The last launch was carried out in 2016 on Shenzhou-11, it docked with the Chinese orbital station Tiangong-2 (Chinese: 天宫, literally: “Heavenly Palace”) as part of this mission.
It is now known that CAST began to develop a new manned ship, its name has not been disclosed. Its main task will be to transport 4-6 taikonauts beyond the low Earth orbit, including the moon. This ship will consist of two modules: the crew module and the service module (the service module will contain life support and power supply systems). The approximate height of the ship will be 8.8 meters, and weight – 21.6 tons. Also, the crew module will be partially reusable, while the ship itself will have a modular design, which will allow it to perform tasks of various kinds of complexity.
So what prevents American astronauts from using Chinese ships to fly to the ISS? The answer is obvious – a political factor. When in 2007 China expressed a desire to participate in the ISS project, although Russia and EU approved this initiative, the USA opposed. This decision then formed the basis of a law passed by the US Congress in 2011 prohibiting NASA and other US organizations from engaging in any kind of scientific activity with China. The main argument: the risk of technological espionage and the use of dual-use technologies by China for military purposes (actually similar concerns in the early 1990s arose among American politicians about Russia’s participation in the ISS project).
Anyway, the Chinese government opted not to wait until the political situation between the US and China improved, but instead initiated its own orbital station, which should be launched in 2022. According to Chinese media, already 17 countries of the world have expressed a desire to conduct scientific experiments on the basis of this station. At the same time, China also does not exclude that the American astronauts could also take part – but only as soon as the American government lifts its ban on space cooperation between the United States and China.
Thus, despite the availability of technology and the experience of successful manned launches, China will be able to provide space launch services for other countries only after 2022, when the new Chinese space station will be launched. As long as the ISS remains the only orbital station of mankind, launching manned spacecraft is simply not reasonable for China, and therefore the market for manned launches in the coming years will be divided between the historical leaders: Russia and the US. However, given the planned launch of Chinese space station, the launch of a new Chinese manned spacecraft, as well as the possible (although unlikely) decommissioning of the ISS, China is very likely to be the leader by the mid-2020s and even be able to determine which countries will receive access to the next orbital station of the Earth.
Denis Kalinin
Scientific journalist
Scientific journalist at the Russian space portal “Outer Space”. Major in Chinese Space industry.
0 Comments