Sunday, May 2, 2010

China's 'Project 921'- Men in Space

China's 'Project 921'- Men in Space

Phillip Clark

This is the original, unedited text which was published in 'LaunchSpace', Oct/Nov 1998 Issue.

The Chinese space program in recent years has been punctuated by well-publicized launch failures interrupting strings of unpublicized launch successes, giving rise to the myth that the Chinese space program is one with low reliability and not in the same class as the programs run by other space powers.

Following high-profile launch vehicle failures, the Chinese have had a string of successes since late 1996. In some U.S. political quarters, these successes owe nothing to the Chinese ability to overcome problems, but are simply due to American help in improving the launch vehicles. Such a claim is an insult to the Chinese engineers and designers. Substantial evidence exists to give substance to China's announcements it plans to begin manned space launches in the second half of 1999.

Starting in the 1970s

The Chinese recovered their first Fanhui Shi Weixing (FSW) satellite from orbit Nov. 29, 1975, succeeding at their first recovery attempt. In this they equaled the Russians, who succeeded on their first recovery attempt, Korabl Sputnik 2. It was not until Discoverer 13 that the United States finally succeeded in recovering a satellite from orbit.

The Chinese recovery led to speculation about a manned program, but in reality, the FSWs were akin to scaled-up Discoverer/Corona satellites with reconnaissance as the primary mission. In all, nine FSW-0 satellites were launched and recovered, five FSW-1s were launched with only the last one failing to return to Earth, and three FSW-2 satellites have been launched and recovered.

Clearly, the Chinese have mastered one important procedure for a manned flight. But they weren't planning to fly people into space in the late 1970s. Rather, although interested in a manned space program, they were only doing the basic ground-based research that such a program would require.

China's "Project 921" manned space program

In November 1988, the Chinese propaganda publication China Pictorial included a series of photographs that apparently showed more men undergoing medical tests while dressed in spacesuits rather than simple pressure suits. It looked as if the Chinese manned program was "on" again.

Two years before, the Chinese had revealed plans for a whole family of new launchers derived from the successfully flown CZ-2C, which could place 2.5 tons into a low-Earth orbit, and the CZ-3, capable of lifting 1.5 tons into a geosynchronous transfer orbit.

When reviewing these vehicles for the July/August 1987 issue of the British Space magazine, this writer identified the CZ-2/4L (today's CZ-2E) as being particularly applicable for manned launches: with an 8.8 ton LEO capability, it could place a Soyuz-class space station ferry into orbit.

Over the last few years, details have started to appear concerning Chinese plans to put people into orbit. Known by its code name, "Project 921," the plan includes flying two astronauts aboard a spacecraft bearing many similarities to the Russian Soyuz which, in turn, was similar to some early 1960s Apollo concepts; the launcher will be a man-rated version of the CZ-2E. The Chinese have bought examples of Russian space technology (e.g., a Soyuz-TM life-support system, an androgynous docking unit and a pressure suit as used by cosmonauts), but they are not copying these - they are learning from them and then applying what they learn to their program.

Having a mass of about 8.4 tons, the Chinese spacecraft has two major external differences compared with Soyuz - it has two pairs of solar panels for the generation of onboard power and the forward module is distinctly cylindrical compared to the spheroid on Soyuz. Additionally, it is thought that up to four people could fly inside the Chinese spacecraft.

From the outset, the Project 921 spacecraft will be equipped with an androgynous docking system and an internal transfer tunnel, which the original Soyuz did not carry. This means that early in their program, two Project 921 spacecraft can be docked nose-to-nose and the two crews can move from one craft to another. When the Russians first did this with Soyuz 4/Soyuz 5 in January 1969, they had no transfer tunnel and two cosmonauts had to perform a spacewalk for their transfer. Two docked Chinese craft could act as a small orbital station for a few weeks, as a precursor to a larger, dedicated space station.

One of the launchers proposed in the mid-1980s was a CZ-3/8L, which essentially has become the three-stage CZ-3B but with eight strap-on boosters instead of four. A logical derivative of this concept would have been a CZ-2/8L, without the third stage. The payload capability would be 16 to 17 tons to LEO. This is heavy enough to launch a space station similar in concept to the original Russian Salyuts of the 1970s and early 1980s.

Satellite images have shown a new launch complex has been built at the Jiuquan launch site, one capable of launching larger vehicles than those that have flown from that site to date. Now confirmed by the Chinese, this launch pad is compatible with a planned all-new family of medium/heavy-lift launch vehicles - believed to be using LOX/kerosene in their lower stages rather than the Chinese standard N2O4/UDMH - as well as the existing CZ-2E vehicle. It is this pad that will be used for launches under Project 921.

What can we expect in the near future? Before the end of 1998, the Chinese should have test-flown both the man-rated CZ-2F vehicle and the Project 921 spacecraft without a crew. A second successful test in the first half of 1999 would clear the way for a two-man launch before the end of that year, conveniently tying it in with the 50th anniversary of the communist takeover of China. A nose-to-nose docking of two Project 921 craft should come two years later.

If all goes according to plan, during late 1999 or early 2000 China will become the third nation to launch its own people into orbit.

Phillip Clark has been studying the former-Soviet space program since the late 1960s and the Chinese program since the first launch in 1970. He publishes the monthly Worldwide Satellite Launches.


It has been widely reported that the Chinese are building new launch facilities at the Jiuquan launch site and that these will be used in support of a new family of launch vehicles for a manned programme. Since the 1980s the Chinese have admitted that they are working on a Saturn-1 class launch vehicle without giving any real details about the project. On October 31, 1992 the Zhongguo Tongxun She news agency in Hong Kong reported that:-

Relevant sources in China's Ministry of Aeronautics and Astronautics Industry have disclose that China's first manned space shuttle will be launched from Jiuquan, Gansu.

According to the information, a space centre designed by Chinese engineers alone, is being built 200 km from Jiuquan City and the construction of a 200 km special railway to the centre has begun. The first phase of the project is expected to be completed towards the end of the 1990s.

At present all the technical officials concerned have taken up their positions. The person in charge here said: "The launch and retrieval of the first space shuttle will take place in the new space centre and the bases in its vicinity. It will take about ten years to accomplish this grand project."

It is now reported that the rail transportation system has been completed and that the launch pad assemblies indicate a launch vehicle far larger than the currently-existing family of Chang Zheng vehicles.

A paper was presented at the 1992 IAF Congress entitled "A Modular Space transportation System" (IAF-92-0857), which described a possible family of future launch vehicles derived from a basic two-stage vehicle which could be clustered in different ways and which could be supplemented additional upper stages. It is unclear whether this paper represents a purely theoretical exercise or whether it is indicative of Chinese planning for future launch vehicles.

The idea behind the paper is the development of a baseline two-stage launch vehicle with the characteristics listed in Table 1.

The Chinese paper notes that the first stage fuel would be a "hydrocarbon (CH)" and this is taken to refer to kerosene - especially since the Chinese would later express an interest in purchasing Russian liquid oxygen/kerosene engines (to be discussed later).

The use of liquid oxygen and kerosene on the first stage of this vehicle would mark a departure for the Chinese, since they have previously used storable UDMH and a nitrogen-derived oxidiser (usually nitrogen tetroxide). The choice of storable propellants is a result of the current launch vehicles being based upon missiles for which storable propellants is virtually essential.

The study called for a baseline vehicle with a length of less than 60 metres and a length/diameter ratio below 13. The study took the diameters of the two stages to be a common 4.5 metres which corresponded to a maximum length of 58.5 metres: in fact, a length of 55 metres was decided upon, including a payload fairing of 12 metres.

Data for the overall launch vehicle are:-

  • launch mass 377 tonnes
  • payload capability 11 tonnes
  • length 55 metres
  • diameter 4.5 metres
  • first stage thrust 4.8 MN [490 tonnes]

One table in the paper notes a launch mass of 337 tonnes, but elsewhere the mass is quoted as 377 tonnes, a figure which is confirmed from simple arithmetic. The numbers imply that the payload shroud would have a mass of three tonnes. The payload mass is quoted in the paper for a 60o, 300-500 km orbit: from calculations by this writer these figures would mean a launch from Jiuquan with a good margin of residual propellant.

On top of the second stage an instrument unit 1.6 metres high would be carried, acting as a data-collection and processing centre for the vehicle.

The first stage would carry four engines which can gimble for control. The second stage a single main engine and a set of four verniers.

Taking this base design, it is proposed that a three-stage launch vehicle could be developed which could place 6 tonnes into geosynchronous transfer orbit: although not stated, one assumes that the third stage would use liquid oxygen and liquid hydrogen - already in use with the existing CZ-3 and CZ-3A launch vehicles.

A series of different launch vehicles derived from the baseline launch vehicle's stages and the not-described third stage is proposed, leading to a maximum payload capability of 70 tonnes to the standard 60o, 300-500 km reference orbit. Details are given in Table 2. For the larger payloads a fairing with a diameter of 5.4 metres and a length of 18 metres would be used.

Thinking in terms of a manned programme, one can imagine that the baseline vehicle could be used to launch the manned spacecraft, while a "Model 1" derivative could be used to launch a space station module.

While the concepts of the 1992 paper are interesting and would represent an extension of the existing Chinese philosophy of taking the basic CZ-2C launch vehicle and modifying it to provide the full variety which we see in the CZ-2, CZ-3 and CZ-4 families, we have no idea whether the 1992 proposals will remain a paper study or will become (or even is !) a funded programme.

No comments: