USAF X-37B
The third mission of the X-37B is schedule for October 2012. The success of this "automated" space vehicle will force the Chinese to develop an automated space shuttle.
Chinese Space Shuttle Programme
In March 1986, under the recommendation of four top scientists, the Chinese government launched the 863 Programme to transform the country's high-tech research and development in eight strategic fields: automation, biotechnology, energy, information technology, lasers, new materials, and space technology.
Under the 863 Programme, two expert groups were set up in February 1987 to conduct preliminary research on human space flight: Project 863-204 was tasked with developing the concept of a crew transportation system and launch vehicle, and Project 863-205 the concept for the manned space station.
The decision to conduct preliminary research on human space flight was in response to a fresh round of international competition in human space exploration. The United States was already operating a fleet of space shuttles, and had just announced its Strategic Defence Initiative (SDI, or 'Star Wars') and the space station Freedom programme. The Soviet Union was building its Mir space station and Buran space shuttle. Japan was developing its spaceplane HOPE-X. The European Space Agency was also developing its space shuttle Hermes.
Inspired by the success of the NASA space shuttle programme, most Chinese space scientists and engineers favoured a winged reusable spacecraft system, i.e. a spaceplane or space shuttle, over the conventional capsule spacecraft vehicle. The Ministry of Aeronautics, one of the strongest advocates for the spaceplane/space shuttle programme, initiated Project 869 to conduct theoretical studies and calculations on the aerodynamic design, propulsion, power supply, airframe, and re-entry and landing of such a system.
Project 869
Scientists and engineers working for Project 869 envisioned a vertical take-off and horizontal landing space shuttle system with a crew of 3~5 men and a total payload of 7 tonnes. The system would be able to fly in the 300~500km Earth orbit, with a mission duration of 2~7 days. The 17-tonne orbiter vehicle would have been 17 metres long, 3.5 metres in diameter, with a wingspan of 10 metres. It would be launched on a booster-enhanced version of the Changzheng 3 rocket. The vehicle would provide 35 cubic metres of internal volume, and be capable of putting a cargo payload of 4 to 5 tonnes into orbit. The first flight of the system could take place as early as 2000.
However, the Ministry of Aeronautics viewed the design as being too conservative and believed that it could become obsolete by the time it would fly. As a result, the project team came up with four much more ambitious horizontal take-off and horizontal landing (HTOHL) spaceplane designs:
Single-stage orbiter, powered by three 50-tonne thrust engines which could operate like jet engines within the atmosphere and rocket engines in orbit.
Single-stage orbiter, powered by six 47-tonne thrust turbofan ramjet engines and four 50-tonne thrust rocket engines.
Two-stage spaceplane, with a winged first-stage powered by six turbofan ramjet engines and a second-stage orbiter vehicle powered by three 26-tonne thrust rocket engines. The orbiter vehicle would be separated from the first-stage at an altitude of 26km and a speed of Mach 5.0.
Two-stage spaceplane, with a winged first-stage powered by sixteen 15-tonne thrust turbojet engines and a second-stage orbiter vehicle powered by four 50-tonne thrust rocket engines. The orbiter vehicle would be separated from the carrier aircraft at an altitude of 18km and a speed of Mach 2.62.
The project report suggested that the overall development would take 15 years, including 2 years in concept studies, 7~9 years in developing the technologies, 6 years in developing the prototype, and 3 years in flight test.
H-2 Spaceplane
The 601 Aircraft Design Institute in Shenyang proposed a two-stage spaceplane concept named H-2. Both stages of the system were fully reusable and adopted the horizontal take-off and horizontal landing (HTOHL) method. The first-stage was a hypersonic lifting body 85 metres in length with a wingspan of 36 metres. The stage would be powered by six LOX/LH2 liquid rocket engines, which would be used for take-off and low-altitude flight, and eight ramjet engines, which would be used for high-altitude acceleration. The second-stage orbiter vehicle would be powered by four LOX/LH2 liquid rocket engines.
Tianjiao 1
The First Academy (CALT) of the Ministry of Astronautics proposed the Tianjiao 1 space shuttle, which would be 20 tonnes in total mass and based on the NASA Space Shuttle design, but only one-sixth in its size.
Changcheng 1
The Eighth Academy (SAST) proposed Changcheng 1, which would be comparable to the NASA Space Shuttle in size. It would be equipped with its own jet propulsion for flight in the atmosphere. The system was designed to transport astronauts and cargo to and from the space station in the Low Earth Orbit, and also be used to carry out Earth observation, scientific research and experiment, space station assembly and maintenance, space station crew rescue, and various military roles.
Changcheng 1 space shuttle concept
Changcheng 1 space shuttle wind tunnel test mockup
A shuttle-style flight simulator in the Chinese astronaut centre
Changcheng 1 would have a flight crew of two men and a mission crew of three men, with a payload mass of 5 tonnes. The system would be able to fly 4 times per year, and be reused for 30 times, with a designed operational life of 15 years. It was estimated that the development of the system would take 20 years, with the first flight to take place in 2008 if the project was to be launched in 1988.
The system consisted of an orbiter vehicle, and three HT-1 non-reusable single-stage liquid-propellant rocket boosters. Each booster was to be powered by four 1,500kN rocket engines burning the liquid oxygen (LOX)/liquid hydrogen (LH2) propellant, with a burn time of 279~300 seconds. The orbiter vehicle had adopted a tailless delta wing layout, and is powered by a 620kN main engine and two 10kN auxiliary engines, all of which would use the N2O4/UTMH propellant. Once the rocket boosters were jettisoned at an altitude of 176.5km, the orbiter vehicle would use its own propulsion to reach a 200 X 500km orbit.
The system would have a launch mass of 1,015 tonnes and a take-off thrust of 1,380kN, giving a thrust-weight ratio of 1.38. The orbital mass would be 39 tonnes. The system would be 55.144 metres in length and 16.7 metres in width. The orbiter vehicle would be 24.7 metres in length and 13.98 metres in wingspan, with a normal landing mass of 31.74 tonnes and an emergency landing mass of 32 tonnes.
Criticism
While most scientists supported the reusable spaceplane/space shuttle option, a small group of scientists and engineers, most of which were from the Fifth Academy (CAST), were in favour of the conventional capsule-type spacecraft vehicle. A team led by the top space scientist Wang Xi-ji in CAST proposed a spacecraft vehicle concept, which could be used to transport crew and cargo to and from the space station, as well as serving as the lifeboat for the future space station.
At the same time, Wang became a leading critic of space shuttle. In his paper published in April 1987, Wang listed a number of disadvantages of the space shuttle, including its safety issue and poor efficiency as a result of its complexity in structure and design. He pointed out that the U.S. space shuttle had failed to achieve its promised cost and utility goals. In September 1987, Wang led a team of delegates to visit several U.S. space facilities and research organisations. Upon his return, he published another paper pointing out that reusability did not equal economy in space exploration.
Wang argued that the ultimate target of China's human space flight programme was to build a permanently-manned space station in the Earth orbit, and the crew transportation system should only be a part of the grander system. Therefore, it would make no sense to spend the majority of the investment and effort solely on an advanced transportation system.
As the Space Shuttle fever began to fade in the early 1990s, the opinions among the senior officials and scientists began to swing towards the conventional non-reusable capsule-type spacecraft vehicle. The restoration of the Sino-Russian relation following the end of the Cold War also made it possible for Chinese engineers to access the Russian Soyuz technology. This eventually led to the decision to develop the capsule-type spacecraft vehicle for China's human space flight programme in 1992.
Last updated: 15 May 2012
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