| By
James Oberg
At the Jiuquan Space Center near the edge of the Gobi Desert in northern
China, Shenzhou 5 is being readied for launch. The spacecraft -- its name
means “divine vessel” in Chinese -- is nearly nine meters
long and weighs almost eight metric tons. Sometime this fall, Shenzhou
5 is scheduled to blast into orbit atop a Chang Zheng (“Long March”)
rocket. Four earlier Shenzhou spacecraft have already made orbital flights,
but unlike these unmanned test vehicles, Shenzhou 5 is expected to carry
a crew of up to three (accounts vary) young Chinese military pilots. If
all goes as planned, China will become the third nation to send people
into space.
Although representatives of three dozen countries have gone into orbit
since the dawn of the space age, they have all traveled aboard either
American or Russian spacecraft. In pursuing its own human spaceflight
program, China has acquired and adapted some technologies originally developed
in Russia and the U.S. Many features of the Shenzhou seem familiar to
space experts; at first glance, the craft looks like a slightly bigger
version of the Russian Soyuz vessel. But China’s space agency built
several key systems on its own, and in some ways the Shenzhou is technologically
superior to the Soyuz.
The first manned flight of the Shenzhou will have profound diplomatic
echoes. In addition to garnering international prestige, China hopes that
its human spaceflight program will stimulate advances in the country’s
aerospace, computer and electronics industries. If the initial missions
are successful, China will probably establish its own space station in
Earth orbit. Within a decade, China’s space activities may well
surpass those of Russia and the European Space Agency. And if China becomes
the most important space power after the U.S., an entirely new “space
race” may be in the offing.
The Upcoming Flight
China’s space ambitions date back to 1970, when a Chang Zheng
rocket boosted Mao 1, the country’s first satellite, into orbit.
(The meter-wide craft transmitted the patriotic song, “The East
is Red,” as it circled the globe.) In 1992 President Jiang Zemin
gave the go-ahead for a manned space program, and the decision set off
a tremendous construction boom that was in some ways as impressive as
NASA’s buildup for the Apollo project in the 1960s. At the Jiuquan
Space Center, the oldest and largest of the three locations where Chinese
missiles and satellites are launched, a new rocket-assembly building and
launch pad were completed in time for the first unmanned Shenzhou flight
in 1999. Although the agency overseeing the program, the Chinese Academy
of Space Technology, has been secretive about certain aspects -- such
as the training of its astronauts -- many technical details about the
spacecraft have appeared in the Chinese press.
The Shenzhou consists of three modules [see illustration on page 00].
The crew will ride in a coffee-cup-shaped unit -- the command module,
in NASA parlance -- that contains their couches (upon which the crew members
lie horizontally during liftoff) and control panels. Attached to the front
of the command module is a cylindrical pressurized unit (referred to as
the orbital module) that will provide additional workspace for the astronauts.
Behind the command module is a cylindrical equipment section (the service
module) holding rocket engines and an electrical power system and sporting
a pair of solar power panels with a total area of 24 square meters.
The official designation of the launch vehicle is Chang Zheng 2F, but
it is also poetically referred to as the Shen Jian (“divine arrow”).
It is a version of the Chang Zheng 2E -- a liquid-propellant rocket derived
from Chinese military missiles -- that has been upgraded to make it reliable
enough for manned flight. Like other launch vehicles of this family that
have been designed to carry heavier payloads, its original four-engine
core is augmented by four strap-on boosters. All the rocket engines use
liquid nitrogen tetroxide and hydrazine propellants, not the more powerful
but troublesome liquid hydrogen fuel used by the space shuttle’s
engines. The Shen Jian’s launch thrust of 604,000 kilograms of force
(kgf) puts it between the standard booster for the Soyuz (411,000 kgf)
and the Saturn 1B (740,000 kgf) that carried several Apollo spacecraft
into orbit between 1966 and 1975.
Shenzhou 5 will take the same flight path as its four unmanned predecessors
[see illustration on page 00]. After liftoff the booster will head east,
crossing the Chinese coastline near Qingdao (site of a new tracking station)
and moving over the Yellow Sea at a maximum acceleration of about five
g’s. Passing just south of the Japanese island of Kyushu, the spacecraft
will be in communications with a large tracking ship and soon achieve
an orbital velocity of about eight kilometers per second. Its orbital
inclination will be about 42 degrees, somewhat more equatorial than the
52-degree inclination of the International Space Station.
To return to Earth, the Shenzhou first jettisons the orbital module. The
service module then fires a small braking engine to slow the spacecraft’s
velocity by about 200 meters per second. This maneuver allows Earth’s
gravity to tug the craft down into the upper atmosphere, where air braking
slows it down further. Because the aim point is a landing zone in Inner
Mongolia about TK kilometers east of the Jiuquan Space Center, the braking
engine fires while the spacecraft is still half a world away, over the
South Atlantic Ocean. After the firing, the service and command modules
separate; the former burns up in the atmosphere, whereas the latter is
equipped on its base with a heat shield that protects the crew from the
searing temperatures of reentry.
The landing sequence follows the pattern of the Soyuz and Apollo spacecraft.
After a relatively high-g deceleration, the command module falls freely
though the lower atmosphere, releasing a drogue parachute at an altitude
of about 30 kilometers and then a larger main parachute. The heavy heat
shield is then jettisoned. Touchdown on the open steppe is softened by
the triggering of a set of rockets in the capsule’s base. Recovery
teams in the zone then rush to the landing point and retrieve the crew.
Shenzhou 1, the first unmanned test vehicle, was launched on November
20, 1999, and spent less than a day in orbit. In each of the three subsequent
flights (launched on January 10, 2001, March 25, 2002, and December 29,
2002), the spacecraft spent a week in orbit as progressively more sophisticated
hardware was tested. Shenzhou 2 carried a monkey, a dog and a rabbit to
test the craft’s life-support system. Shenzhou 4 was described as
a completely human-capable vessel, with all the equipment needed to accommodate
three people. In fact, astronauts reportedly took part in the countdown
inside the command module, leaving the craft only a few hours before liftoff.
Copy of Soyuz?
Because of the Shenzhou’s superficial resemblance to the Soyuz,
many observers concluded that the Chinese vehicle was nothing more than
a knockoff with only minor modifications. David Baker, editor of the British
publication Jane's Space Directory, said the Shenzhou is "a Soyuz
to a very considerable extent -- it’s off the shelf, as it were."
But Brian Harvey, author of The Chinese Space Program: From Conception
to Future Capabilities (Wiley-Praxis, 1998), has criticized this view.
“There are a lot of misperceptions about the Chinese space program,”
Harvey says, referring to myths of low-technology spacecraft and widespread
copying of foreign designs. “A lot of it reflects a Western cultural
notion that the Chinese couldn't possibly master this kind of technology.
I think it's more helpful to look at the way in which the Chinese have
built their program up over the years -- slowly, patiently, carefully,
in a disciplined way, with the careful selection of choices, borrowing
from elsewhere, but only to a limited extent.”
Most other independent experts agree. Some reports indicate that although
the Chinese had asked to purchase a fully-functional Soyuz vehicle for
study, the Russians demanded a price so high that the deal never took
place. The capsule they bought was a stripped-down version missing many
key space systems. And the Chinese may also have picked up at least one
off-course unmanned Soyuz-class capsule that crashed inside their country
early in the space age.
The three-module design of Shenzhou is a logical arrangement, first developed
independently by U.S. and Soviet teams more than 40 years ago. Shenzhou
looks less like today’s Soyuz than like the preliminary designs
for Soyuz and Apollo. Although Shenzhou’s command module has some
similarities to Soyuz’s reentry capsule, the other modules are quite
different from their Russian and American counterparts. The service module,
for example, has four main engines, whereas Apollo’s service module
had only one and Soyuz has one main and one backup engine. Also, Shenzhou’s
large solar arrays generate several times more electrical power than the
Russian system. And unlike Soyuz, the Chinese orbital module carries its
own solar panels and independent flight control system, allowing it to
continue as a free-flying unmanned mini-laboratory long after the reentry
module has brought the crew back to Earth.
One example of outright Chinese copying is in the cabin pressure suits,
used to protect the astronauts in case of an air leak during flight. The
Russians introduced such a survival suit (called the Sokol) in 1972 after
three cosmonauts died in an accidental cabin depressurization during their
return to Earth. (A much more sophisticated suit is used for spacewalks.)
The Chinese needed a suit with similar functions, so after obtaining samples
of the Sokol design they copied it exactly, right down to the stitching
and color scheme.
Chinese officials have made no secret of such technology transfers. A
lengthy article on Chinese space plans appearing in the Xinhua News Agency’s
magazine Liaowang in 2002 stated: “After China and Russia signed
a space cooperation agreement in 1996, the two countries carried out very
fruitful cooperation in docking system installations, model spaceships,
flight control, and means of life support and other areas of manned space
flight. Russia’s experience in space technology development was
and is of momentous significance as enlightenment to China.”
The mention of docking systems is especially illuminating. Although Russia
and the U.S. have used different types of docking mechanisms over the
years to link spacecraft in orbit, photographs of Shenzhou indicate that
the Chinese have chosen a Russian variant called the APAS-89. The device
consists of a pressurized tunnel 80 centimeters in diameter surrounded
by sloping metal petals that allow any two units of the same design to
latch together. Originally developed for the Russian Mir space station,
the APAS-89 is used to dock NASA’s space shuttles to the International
Space Station (ISS). Although China is primarily interested in docking
its spacecraft with its own small space stations, the decision to employ
the APAS-89 mechanism allows Shenzhou to link with both the space shuttles
and the ISS.
Building the Booster
The development of the launch vehicle for the Shenzhou also illustrates
China’s space technology strategy. The rocket is an outgrowth of
earlier versions used for scientific and commercial launches, but some
very specific improvements have been made. According to Liu Zhusheng,
the chief designer of the Chang Zheng 2F booster, the reliability of the
vehicle is rated at 97 percent -- that is, it is expected to fail in only
three of 100 launches. (The rated reliability of the unmodified Chang
Zheng boosters is 91 percent.) Furthermore, the Shenzhou can separate
from its booster in the event of a launch catastrophe. Speaking to Xinhua
News Agency reporters last January, Liu described an entirely new malfunction-diagnosis
system to monitor the booster’s status and, if needed, activate
backup mechanisms or initiate the spacecraft escape. He claimed that the
escape system gives the crew a survival probability of 99.7 percent.
Shenzhou’s launch escape system is based on the “tractor rocket”
scheme originally developed for NASA’s Mercury flights in the early
1960s and later adopted by the designers of the Apollo and Soyuz spacecraft.
A set of solid-propellant rockets mounted on a tower on the nose of the
Shenzhou pulls the spacecraft clear of the booster in the event of a launch
disaster. The spacecraft then parachutes to the ground. The solid-fuel
rockets are armed from 15 minutes before liftoff until 160 seconds afterward
(at which point the spacecraft is at an altitude of 110 kilometers).
In an interview with People’s Daily, the official newspaper of the
Chinese Communist Party, launch vehicle manager Huang Chunping showed
a reporter a model of the booster that had four wings on the payload fairing
that surrounds the Shenzhou during liftoff. The wings, each resembling
a lattice, are required to keep the Shenzhou stable during a launch escape.
“This is the most difficult part of the escape system,” he
explained. “We once wanted to inquire about it from Russian experts,
but they set the price at $10 million. Finally we solved the problem on
our own.” This pattern of studying previous work but designing the
actual flight hardware independently was followed on most other Shenzhou
systems.
Astronauts and Infrastructure
China did, however, receive Russian help in training its astronauts.
As part of the 1996 cooperation agreement between the two countries, two
Chinese military pilots -- Wu Jie and Li Qinglong -- took courses at Russia's
Gagarin Space Flight Training Center in Star City outside Moscow. They
reportedly are now directing the training program for China’s flight
candidates. Twelve other pilots were later picked to join them in the
first group of Chinese astronauts. Last January, Hong Kong newspapers
named Chen Long as the leading candidate for the command of the first
manned flight.
All the Chinese astronauts are young university-educated jet pilots with
more than 1,000 hours of flying experience. Because the Shenzhou, like
the Soyuz, has a limited amount of cabin space, small stature is a requirement:
each astronaut is under 170 centimeters (five feet, seven inches) tall
and weighs less than 65 kilograms (143 pounds). What the Chinese astronauts
should be called is still in dispute. One Chinese space enthusiast coined
the term "taikonaut," from the Chinese “tai kong,”
or “outer space.” However, Chinese officials and newspapers
prefer "yuhangyuan," which roughly translates as "space
navigator."
In preparation for the Shenzhou missions, China vastly improved its facilities
for spaceflight research and training. The new China Space Center in Aerospace
City, a southwestern suburb of Beijing, is home to a collection of pressure
chambers, space vehicle simulators, a centrifuge and a landing impact
tower, along with classrooms and medical facilities for astronauts. Mission
control for the Shenzhou flights is located here. Also, the new Space
Technology Research and Test Center in Tangjialing, northwest of Beijing,
includes spacecraft integration halls, space environment chambers (such
as the world’s fifth largest vacuum chamber), vibration test facilities
and laboratories.
What is more, China has launched four ocean-going ships to track its missiles
and spacecraft. These Yuan Wang (“Long View”) ships have been
deployed in the Pacific Ocean to monitor military missile tests and in
the Indian Ocean to control the maneuvering of satellites into geosynchronous
orbit. The ships are sent into the South Atlantic, Indian and South Pacific
Oceans to support the Shenzhou flights. The Russians used to have a similar
fleet but scrapped it in the 1990s because of budget constraints. Rather
than purchase the Russian ships, China built its own.
Because some of the critical ground-control functions for the Shenzhou’s
return to Earth must be performed while the craft is over the South Atlantic,
China signed an agreement with the African nation of Namibia in 2000 to
build a tracking station near the town of Swakopmund. Construction started
in early 2001 and was completed by year’s end. Five permanent residents
occupy the facility, and the staff expands to 20 during missions. The
site lies under the reentry path of the Shenzhou, and because the craft’s
orbit has a different inclination than the International Space Station’s,
the Namibian base could not be used to track flights returning from there.
This suggests that despite the Shenzhou’s compatible docking gear,
the Chinese seem to have no near-term interest in visiting the ISS.
China’s Goals
The first unmanned test flight of Shenzhou in 1999 prompted a great outpouring
of national pride. "Landmark Launch Shakes the World!" thundered
People’s Daily. But to justify the expense of the Shenzhou program
-- officials say 19 billion yuan, or $2.3 billion, have been spent so
far -- China surely expects more than feel-good headlines. The government
anticipates that a successful manned space program will enhance China’s
world status and the reputation of its high-tech exports, giving the country
greater diplomatic and commercial power.
Furthermore, China sees space technology as critical to quickly achieving
technological parity with Western nations and Japan. A white paper issued
in 2000 by the Information Office of the State Council claimed that the
space industry is “an integral part of the state's comprehensive
development strategy.” According to an article in the June 2000
issue of Xiandai Bingqi, the monthly journal of a military technology
research institute, the human spaceflight program “will raise levels
in areas such as computers, space materials, manufacturing technology,
electronic equipment, systems integration and testing.” The journal
also notes that the experience of developing spacecraft navigation, propulsion,
life support and other subsystems could be applied to “dual-use
military/civilian projects."
Under this national space plan, China plans to build an impressive stand-alone
space capability on a narrow technological base. Instead of developing
a wide variety of aerospace technologies, as the U.S. has done over the
past four decades, China will focus on specific areas where it can match
and then out-do the accomplishments of other nations. In an article appearing
in People’s Daily in April 2000, Luan Enjie, director of China's
Aerospace Bureau, explained: “With limited state financial resources
and very weak industrial and technical foundations, we do not have the
strength to comprehensively catch up with and surpass world advanced levels
in all aerospace fields. Over the past thirty years, China's aerospace
industry has persistently followed its own developmental path.”
Although China is still far from challenging the space status of the U.S.,
it may have more attainable goals in mind. If there is a new space race
under way, it’s for second place. Russia’s space program faded
in the 1990s and now preserves its remaining capabilities only through
massive commercial sales to Western customers. With a GNP and federal
budget five times as great as Russia’s, China can easily afford
to outspend America’s former chief rival in the space race. But
the Chinese are not being profligate. The $2.3 billion that China has
reportedly spent on the Shenzhou project over the past decade is a little
more than half of what NASA spends on the space shuttle every year.
The burgeoning Chinese space program is already beginning to eclipse the
European Space Agency (ESA), which has never sent astronauts into orbit
but leads the world in launching unmanned commercial satellites. The ESA
faces political disenchantment among its member states and cuts in its
space research budget. Brian Harvey, author of The Chinese Space Program:
From Conception to Future Capabilities, says it is possible that over
the next five years China will match the ESA’s launch rate (about
10 launches per year) - and that already seems to be happening. “Europe's
launches will be mainly commercial and scientific, whereas China will
concentrate on applications and its manned program,” Harvey says.
In 2001 Roger-Maurice Bonnet, the retiring director of the ESA Science
Program, declared that European governments must make the political decision
to spend what it takes to maintain the ESA's second-ranked position in
space research (after the U.S.). Otherwise, warned Bonnet, China would
overtake the Europeans within a decade.
Many space experts agree that China's drive to overtake the Europeans
and Russians is entirely credible. "China certainly has the political
will to forge ahead with its space program," says Joan Johnson-Freese,
formerly of the Asia-Pacific Center on Security Studies and now with the
Naval War College. "[China] recognizes all the internal and external
prestige-related benefits of space that the U.S. and the FSU [Former Soviet
Union] did in the 1960s, as well as the technology-industrialization-economic
benefits that pushed Europe into space later."
Next Steps
As evidence of their determination, China’s space officials have
already laid out the steps to follow the initial manned Shenzhou missions.
The aforementioned 2002 article in Liaowang magazine described the development
plan: “After it succeeds in manned space flight, China will very
soon launch a cosmic experimental capsule capable of catering to astronauts’
short stays.” This capsule is elsewhere described as “a laboratory
with short-term human presence,” to be followed later on by a space
station designed for long-term stays. Last January, unnamed officials
provided further background to Xinhua News Agency reporters: “As
the next step, China will endeavor to achieve breakthroughs in docking
technology for manned spacecraft and space vehicles, and will launch a
skylab. After that it will build a long-term manned space station to resolve
problems related to large-scale space science experiments and applied
technology and to make contributions to mankind’s peaceful development
of outer space.”
Zhang Qingwei, a leading official of the Chinese agency overseeing the
Shenzhou program, told People’s Daily last January: “[The]
orbital cabin [remains in space] to lay a foundation for China’s
second-step manned spaceflight project -- forming a docking link between
a spacecraft and another flight vehicle.” Observers generally interpret
this to mean that a near-future Shenzhou mission will leave its specially-equipped
orbital module in space, where it will then serve as a rendezvous and
docking target for the next Shenzhou launch. Once this capability has
been demonstrated, China could proceed directly to the small space laboratory
(a photograph of a high-fidelity mockup has already been released).
Phillip Clark, a British space consultant specializing in Russian and
Chinese technology, expects China’s space agency to launch a small
12- to 14-ton laboratory, perhaps within the next two years. Clark predicts
that in 2006 or 2007 China will loft a station similar to the Russian
Salyut stations launched in the 1970s and 1980s (with masses ranging from
20 to 40 tons). Finally, according to Clark, China will begin the orbital
assembly of a structure like the 130-ton Russian Mir station, which flew
for 15 years before burning up in a planned reentry in 2001. (The partially
assembled International Space Station currently has a mass of nearly 200
tons.)
In addition, China has been accelerating its deployment of unmanned satellites
for communications, weather, navigation and space research. Chinese officials
have also discussed plans to land small remote-controlled rovers on the
moon, equipped with cameras and manipulator arms, by 2010. Some Western
media have reported that China wants to eventually land astronauts on
the moon, but these accounts have come from unofficial sources and may
have been mistranslated. A manned mission to the moon would be many times
as expensive as the Shenzhou project, whereas the payoffs might be only
incrementally more.
According to space experts such as Brian Harvey, boosting astronauts into
orbit will be enough to make the world see China in a new light. “Public
and media perceptions are all-important,” Harvey says. “If
China puts astronauts into space, there will be a perception that the
country has reached space superpower status. If China follows that with
its own Salyut-class space station, it will impress the Asian region specifically
and the world as a whole.” China’s goals for its space program
are obviously not the same as America’s, Russia’s or Europe’s.
Judging from the hardware already built and the infrastructure in place,
it seems clear that China intends to follow its own path in space for
the foreseeable future.
|