OBERGlayout0913_Layout 1 8/19/13 1:26 PM Page 2 China space 2.0 China’s latest space plans are moving ahead at full speed, with new space vehicles, launch facilities, and manufacturing sites already taking shape. Success, however, will require that these complex elements come together simultaneously and work as intended, a daunting challenge. But if assets such as a new family of heavy-lift boosters perform as promised, they will greatly increase China’s future space capabilities. What this may imply about the country’s long-term national goals is an unanswered question. The next LEAP forward 38 AEROSPACE AMERICA/SEPTEMBER 2013 Copyright ©2013 by the American Institute of Aeronautics and Astronautics OBERGlayout0913_Layout 1 8/19/13 1:26 PM Page 3 he Chinese space program, after this regard. They offer so many options that an impressive two-decade pro- there appear to be virtually no constraints gression through modest, year- on any combination of new space goals. by-year improvements, now faces perhaps the most challenging Engines T‘great leap’ in its history. If the effort suc- The ‘jewel in the space crown’ of these ceeds, it will enable far more ambitious new capabilities is the Long March 5 (LM space activities in the coming decade and or CZ-5) booster, an intermediate-class beyond. rocket (think Saturn 1B, or Proton, or Ari- Years-long construction, development, ane 5) with an initial flight rate of up to 10- and testing are on the verge of simultane- 12 per year, and downstream capability to ously activating a new spacecraft and more than double that. booster production facility, a new family of For the past 20 years, most Chinese boosters, and a new, more capable launch spacecraft have been launched on varia- site. The era of ‘China space 2.0’ is about to tions of the Long March 2, 3, and 4 boost- begin, and Western observers are both im- ers. These rockets are based on the hyper- pressed by the undertaking and uncertain golic-fueled military ICBM Dong Feng 5, about its national goals. whose two YF-21 engines had a thrust per A primary principle of technological in- engine of 284 tons. This Long March family telligence analysis is that observed capabil- with its paired core engines (YF-21B) has ities under development reflect national in- placed up to 9.5 tons in LEO with strap-ons tentions and goals. But China’s imminent or, with upper stages, carried 3-5 tons to new space capabilities are ambiguous in GEO transfer orbit. The fairing for the LM-5 is being developed with an eye to the future. by James Oberg Contributing writer AEROSPACE AMERICA/SEPTEMBER 2013 39 OBERGlayout0913_Layout 1 8/14/13 12:09 PM Page 4 Soon after 2000, in a decision appar- Although stretched central cores and added ently made in several stages, the govern- strap-ons allowed incremental enhance- ment approved the development of two ment of performance, a design ceiling had major new engines that reflect more ambi- been reached, literally: Rockets bigger than tious goals. They are the YF-100, a new about 3.35 m in diameter and 14 m long kerosene-LO2 rocket engine rated at 120 did not fit through the railroad tunnels. tons thrust (twice the thrust of the previous To break this impasse, space planners strap-on stage engine), and YF-77, an LH2/ began an across-the-board infrastructure LO2 core engine with a thrust of 50 tons. upgrade. This involved construction of en- A new family of smaller upper-stage tirely new booster and spacecraft fabrica- engines, both hypergolic and cryogenic, was tion and test facilities with seagoing ship to be created as well. access, along with a coastal launch site at As engine development proceeded, de- the other end of the water route. For range sign work on the booster family that would safety as well as launch dynamics consider- use these engines proceeded in parallel. ations, the site chosen was on Hainan Is- Three tank diameters were envisaged: a land, near 19 deg N. 2.35-m tank with a single YF-100 engine, a As noted in a ‘space white paper’ in 3.35-m tank with two YF-100s, and a 5-m late 2011, the new booster family was des- tank with two YF-77s. ignated Long March 5, 6, and 7. The papers, The design of the biggest version, the released by Beijing at five-to-six-year inter- LM 5, specifies a length of 60 m, with four vals, have proved to be reliable indicators engines. For LEO missions, the central 5-m of broad national space goals, although core is assisted early on by four 3.35-m liq- they are not complete (no military applica- uid strap-ons, and goes all the way into or- tions are mentioned). First flights were bit. The payload weight would increase planned for late 2014, a date that has now two-and-a-half to three times over that of begun slipping. current boosters—up to 25 tons in LEO. One indicator of the care that develop- The LM 7 variant, which is looking ers were taking in these fundamentally new more and more likely to be the first of the design efforts was a February 20, 2012, arti- new family to actually fly, will use a 3.35-m cle on digital prototyping of the booster. core with 2.35-m strap-ons plus an upper According to the article, published on the stage. It is also considered likely to become China Aerospace Science and Technology the replacement for most LM 2 variants over (CASC) website, this is the first time in the the next 10 years. history of Chinese rockets that an entire rocket model has been digitally engineered. Breakthroughs in logistics and design The most difficult aspect of the effort was The new booster family was not the only that in the absence of past experience, all- needed breakthrough. Up until then, Chi- new computing methods and design con- nese spacelift was constrained by limited cepts were needed. thrust, but also by a very down-to-Earth Unlike its predecessors, the LM 5 pro- practical limitation: the logistics of trans- gram uses 3D design methods. Tests are porting booster components from their fac- now conducted through simulation soft- tory to launch sites that were all far inland. ware, which increases reliability and saves great amounts of manpower, material, and money. The CASC article explained that The Long March (or CZ) series was robust even before the advent of the LM 5, 6, and 7. digital model testing is done prior to testing on a physical model. Then, after the digital and physical models are compared for any differing results, the digital model’s param- eters are further refined. The first production YF-100 engines had completed acceptance testing by June 14, 2012. In a statement released by the Xinhua News Agency, the State Administra- tion of Science, Technology and Industry for National Defence reported: “The 120-tonne liquid oxygen/kero- sene high-pressure staged combustion cycle engine will provide an effective guarantee 40 AEROSPACE AMERICA/SEPTEMBER 2013 OBERGlayout0913_Layout 1 8/14/13 12:09 PM Page 5 The LM-5 first stage hydrogen tank is part of a breakthrough in Chinese rocket design. for the country’s manned space and lunar “The building of a space station re- probe missions. This high-performance en- quires carrier rockets with greater thrust, as gine is nontoxic, pollution-free and reliable. each capsule of the station will weigh about “It is the first kind of high-pressure 20 tonnes,” Jing Muchun, chief engineer for staged combustion cycle engine for which the carrier rocket system of China’s manned China has proprietary intellectual property space program, told Xinhua on September rights,” the statement continued. “It also 29, 2011.”We have been preparing for the makes China the second country in the launch of the space station, slated for world, after Russia, to grasp the core tech- 2020.” Jing’s deputy, Song Zhengyu, told nologies for a liquid oxygen/kerosene Xinhua that the new generation of carrier high-pressure staged combustion cycle rockets, using digital flight control systems rocket engine.” and nontoxic, nonpolluting propellants, Lai Daichu, the test commander, told would take about seven years (2014-2021) newsmen that the tests were designed to to phase in. During that period existing see how the engine would respond to rota- Long March 2, 3, and 4 series would be re- tional speeds of nearly 20,000 rpm and placed sequentially. temperatures of 3,000 C for 200 sec. “The While LM 5 was the heavy lifter, the successful tests confirm the reliability of smalle r LM 6 and LM 7 would have special China’s LOX/kerosene engine,” he said. missions. LM 6 is to be a new type of quick- A few weeks later, Luan Xiting, identi- response launch vehicle, capable of placing fied as deputy director of the Academy of not less than 1 tonne of payload into a Sun- Aerospace Propulsion Technology under synchronous orbit at a height of 700 km. CASC, elaborated on the testing process: The LM 7 will be able to place 13.5 tonnes “Adequate tests are essential to expose its in low-inclination LEO (it is expected to be weaknesses and discover its problems, so human rated for Shenzhou spacecraft), and we can come up with right solutions,” he 5.5 tonnes of payload into a Sun-synchro- told a Beijing television station. “For some nous orbit at a height of 700 km, according 60 engines, we have tested over 120 times to the white paper.
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