"Чанчжэн-7" (CZ-7, Long March-7, LM-7)

[Salo]

http://www.aviationweek.com/aw/generic/story_channel.jsp?channel=space&id=news/awst/2010/11/22/AW_11_22_2010_p26-270737.xml&headline=null&next=20

Long March 7, DFH-5 Advance Toward Service

Nov 23, 2010

By Bradley Perrett
Beijing

The CALT Long March 7 medium-heavy space launcher will go into production in 2014, according to current plans, completing a new family of Chinese rockets with new fuels and engines.

Sized between the Long March 5 and 6, the new rocket will offer up to 720 tons (1,590,000 lb.) of liftoff thrust from six engines fed by liquid oxygen and kerosene.

The first stage of the Long March 7 will have two YF100 engines, CALT Vice President Hao Zhaoping tells Aviation Week. The YF100 is already known to have a thrust of 120 tons.

The rocket will also have four boosters, each with one YF100, Hao says, apparently describing the launcher's maximum configuration. The Long March 7's previously stated throw weight to low Earth orbit, 10-20 tons, indicates that it would be built with a variable number of boosters.

The second stage will have an engine developing 18 tons of thrust.

"The Long March 7 will be easier to develop than the Long March 5," says Hao. "But it is, after all, a completely new rocket. There will be difficulties in [designing for] some of the loads, and there will be some new material."

New aluminum alloys, with greater strength, will cut weight a little, he adds.

Four more years of development will be needed before production begins. The Long March 7 is therefore not far behind the Long March 5, which is due to fly in 2014—a target which has slipped several times but which Hao now confirms. The Long March 5 is now in the engineering model phase, he says.

The biggest engineering challenge is in maintaining a precise shape for the 5-meter-dia. (16.4-ft.) body. China's earlier standard rocket module diameters, to be used again for the Long March 6 and 7 and the boosters for all three, are 2.25 and 3.35 meters.

Hao did not mention any other technology as a great problem in developing the Long March 5, such as the liquid hydrogen and liquid oxygen engines of the rocket core stages.

"The Long March 2, 3 and 4 will be the foundation of the launcher capability for a fairly long time, because they are increasingly mature and reliable," the executive says, echoing comments by the vice president of sibling company SAST, Meng Guang, who says the older generation will last at least 10 more years.

"The Long March 5, 6 and 7 must first become mature," says Hao.

The key difference between the two families is that the older Long Marches use hydrazine fuel, which presents fewer challenges to engine designers but is costly, toxic, hard to handle and, for a given weight, has much less energy than kerosene.

Spacecraft specialist CAST, meanwhile, expects that the first satellite based on the DFH-5 bus should be launched in 2016 or 2017, addressing the active market for large platforms. Development is scheduled for the next five-year economic plan of the Chinese government, covering 2011-15, says CAST President Yang Baohua.

"Currently, there are no great difficulties in the development," Yang tells Aviation Week. "It is just an issue of scale, because we do not need to make any particularly difficult breakthroughs in the concept as we move to the DFH-5 from the DFH-4," which is now CAST's biggest bus.

The DFH-5 is a "large, trussed satellite platform" that will "meet the needs of new-generation, large geostationary communications satellites and Earth-observation satellites," CAST says.

The DFH-4 was initially unreliable, but Yang says its problems have been "basically" resolved.

"We can say that the DFH-4 has progressed from failures to success, and now from success to maturity. Next it will progress from maturity to international recognition," he says.

While the DFH-4 is now CAST's main offering, the smaller DFH-3 still has a future, Yang says, speaking at the Airshow China exhibition here. Part of the order for eight satellite buses placed at the show by affiliate China Great Wall Industry Corp., though stated to be DFH-4s, might be DFH-3Bs, an uprated version of the earlier bus.

The DFH-4 has a launch mass of 5.1-5.4 tons, payload of 600-800 kg. (1,320-1,760 lb.) and power of 10.5 kw. The figures for the DFH-5 are 6.5-7 tons, 1,200-1,500 kg. and 15-20 kw.

CALT (the China Academy of Launch Vehicle Technology), SAST (the Shanghai Academy of Spaceflight Technology) and CAST (the Chinese Academy of Space Technology) all belong to national space contractor CASC (China Aerospace Science & Technology Corp.).

An order for 20 Long March 3s from China Great Wall Industry Corp. will help CALT to boost production of that rocket. The separate order for eight spacecraft buses will support CAST's current production rate.

The two deals—in effect, internal group transactions—were together worth 15 billion yuan ($2.26 billion). China Great Wall acts as a shop front for CASC products. It will receive the rockets and buses over the next five years.

Long March 3 production will rise by at least 50% from its current rate of 12-15 a year, says Hao. The higher rate will reduce costs, but only a little, because the launcher is already a mature product.

CAST expects to loft 14 satellites this year and 20 next, including four based on the DFH-4 bus, with three more of that model under construction, Yang says.

DFH-4 Photo: China Great World Corp.

[Salo]

http://spaceflight.esa.int/strategy/pages/Home__Events__Why_the_moon__1_6_Tangming.cfm

Если я правильно понял: Base Type 1 - это CZ-5, Base Type 2 - это CZ-7 ?

Да, она же CZ-2H

[Salo]

http://www.sinodefence.com/space/launcher/cz7.asp

Changzheng 7

Originally known as Changzheng 2F(H), Changzheng 7 is the PRC's new-generation liquid-propellant, medium-lift launch vehicle currently being developed by the China Academy of Launch Vehicle Technology (CALT). The launch vehicle is designed to deliver 10,000~20,000kg payload to the Low Earth Orbit (LEO). Once commissioned, the launch vehicle will replace the Changzheng 2F currently in use for the human spaceflight missions. The first launch of the booster is expected to take place in 2012~2013.

The Changzheng 7 launch vehicle is based on the airframe of the Changzheng 2F, but fitted with new generation rocket engines that burn the non-toxic, non-polluting liquid-propellant. The first stage of the launch vehicle is fitted with two 100t-thrust YF-100 liquid-propellant (LOX/Kerosene) rocket engines to replace the original four YF-20 liquid-propellant (N2O4/UDMH) engines. The second stage of the launch vehicle is fitted with a single 100t-thrust YF-100 engine to replace the original YF-20 engine. The 2.25m-diameter strap-on boosters will have a single YF-100 engine to replace the original YF-5 engine.
Changzheng 7 will be available in two variants: the cargo variant with a 13,000kg LEO capacity and a launch weight of 579t; the manned variant with a 12,500kg Leo capacity and a launch weight of 582t. The manned variant will also be equipped with an emergency escaping system.

Last update: 1 Nov 2010

[Salo]

А они ЦБ будут дросселировать? Ведь стартовая масса у него примерно в два раза больше чем у боковушки, но и двигателей два.

[Петр Зайцев]

Зачем дросселировать, если на нем сверху и так сидят K3-2 и H3-3?

[Salo]

Т.е. ЦБ с боковушками сбрасываются одновременно?

[Петр Зайцев]

Ну я надеюсь... Ведь нужно быть сотрудником ISRO, чтобы придумать РН у которой центр выгорает, а боковушки тянут его еще чуть ли не 90 секунд.

[Петр Зайцев]

Кстати, 2.25 * sqrt(2) = 3.18, а не 3.35. Так что в К3-1 должно лезть больше чем в 2 раза больше топлива, чем в К2-1, при той же длине.

[SpaceR]

Ну я надеюсь... Ведь нужно быть сотрудником ISRO, чтобы придумать РН у которой центр выгорает, а боковушки тянут его еще чуть ли не 90 секунд.

Ххе! А Вы, по-моему, случайно попали в точку!  
Думаю, у CZ-7 как раз и будет раннее выключение ЦБ и окончание полета на боковушках - это мне представляется единственным вариантом обеспечения приемлемых перегрузок (ракету ведь для Шэнь Чжоу прочат, если не путаю) при использовании движка, качающегося только в одной плоскости.

Если лететь только на ЦБ, без боковушек, то невозможно обеспечить управляемость по всем трем осям - движков-то два!
А если выключать все одновременно, то перегрузка будет больше 5 имхо. Да и остатки увеличатся (сложнее синхронизировать).

Конечно, если воткнуть на ЦБ движки с двухстепенным карданом, то всё упрощается и возможна почти союзовская схема (с дросселированием ЦБ и сбросом боковушек).

А у ISRO тоже причины были. Оправдывая столь нестандартное решение, они писали, что было проанализировано более 150 различных схем GSLV, и результирующий выбор соответствовал наилучшему соотношению триады характеристики-надежность-стоимость.

[Дмитрий В.]

Вообще-то никто не отменял дросселирование. Будет что-то вроде Ангары-5. Да, и ничто не запрещает двигатель качать в двух плоскастях - кардан уже изобрели!  Кстати, на рисунке движок мне кажется именно с карданным подвесом.

[Salo]

И добавочные примерно 10т топлива в ЦБ эту мысль подтверждают.

[SpaceR]

И добавочные примерно 10т топлива в ЦБ эту мысль подтверждают.

Cкорее всего, даже не 10, а 12 т.
Но они ничего не подтверждают, поскольку оба блока проектировались под применение в составе CZ-5 - и именно это объясняет, почему у двухдвигательного больше относительный запас.

А так я выше уже написал, что при появлении движка YF-100 с двухстепенным карданом будет "союзовская" (ну, пусть "востоковская") схема. Хотя можно назвать её и "ангарской", поскольку ЦБ будет дросселироваться.

Но не исключено, что схема с неразделяемым пакетом и ранним выключением ЦБ полетит раньше.
Посмотрим...

[SpaceR]

Longer Marches[/size]
Mar 15, 2010
 By Bradley Perrett, Beijing

The Chinese space industry is studying a Moon rocket in the class of the Saturn V while separately moving ahead with a medium-heavy launcher that will complete a modern, modular family of launch vehicles.

Chinese space engineers appear to be planning to assemble manned lunar spacecraft in orbit with two or more launches per mission.

The medium-heavy launch vehicle, previously foreshadowed as a relative of the new Long March 5 heavy launcher, is being developed under the name Long March 7. Long March 5 and 7 and the lighter Long March 6 will form a family of rockets, says the China Academy of Launch Vehicle Technology.

Chinese industry will maximize economies of scale in production by building the three basic vehicles for a wide range of payloads while, in almost all applications, using only three basic stage modules and, apparently, two engine types.

The launcher for manned lunar missions, several times larger than even the Long March 5, would have a thrust at lift off of 3,000 tons, says the vice president of the academy, Liang Xiaohong, adding that the payload has not been defined. By comparison, the S-1C first stage of the Apollo program's Saturn V generated 3,470 metric tons at sea level.

The news of Chinese studies into such a mighty launcher comes as the Obama administration seeks to cancel the U.S. equivalent, the Ares V of the Constellation program, whose six main engines and two solid-fuel boosters would put out about 4,300 tons of thrust.

Since the lift-off thrust of the launcher will be lower than that of the Saturn V, it will be unable to deliver as great a mass to lunar orbit—probably about 35 tons, compared with the U.S. launcher's 45 tons, estimates one U.S. rocket engineer. But NASA needed that 45 tons for missions that were close to the minimum conceivable—brief stays on the Moon by two astronauts. Moreover, the Apollo equipment was built so lightly that even now the Chinese would probably struggle to do that minimum mission with much less mass.

So the thrust of the proposed Moon rocket strongly suggests that Chinese engineers plan to launch their lunar craft in at least two parts and assemble it in low Earth orbit, as NASA planned in the Constellation Program by launching the crew capsule separately. In proposing a Moon launch vehicle, the Chinese engineers are avoiding the risky alternative of a longer succession of Long March 5 launches.

Getting 3,000 tons of thrust under a single rocket presents a formidable technological challenge for China, whose largest engine so far, the YF-100, generates thrust of just 120 tons. The Soviet Union's disastrous experience with the 30-engine first stage of its N-1 lunar launcher argues against attempting such an arrangement with the YF-100.

China could alternatively develop or buy larger powerplants. The five F-1 engines of the Saturn V each generated 694 tons of thrust. The Russian RD-171, used on the Zenit launcher, puts out 770 tons from four thrust chambers. Four RD-171s would deliver 3,080 tons, and they would probably fit into a rocket airframe with a diameter of 8-10 meters (26-33 ft.), says the U.S. engineer.

An official from the Chinese space industry base under construction at Tianjin said last year that the plant could be adapted to handle rocket diameters of 8-10 meters. The Saturn V's first-stage diameter was 10.1 meters.

The YF-100 seems to have been developed with Russian technology and is a key element in the family of smaller launchers that China already has in development. While there are few new details from Chinese industry, synthesizing them with earlier information suggests that two YF-100s will act as the first-stage engines for the Long March 7.

China is developing three basic rocket modules, with diameters of 2.25 meters, 3.35 meters and 5 meters and lengths that vary with their roles as first or second stages or side-mounted boosters. Matched with those modules are two new engines, the kerosene-fueled YF-100 in the two narrower bodies (hence module names, K2 and K3) and the liquid-hydrogen fueled, 50-ton-thrust YF-77 in the wider module (called H5). If the Chinese are following plans revealed a few years ago, then two stacked K2 modules form the Long March 6 while two stacked K3s make up the core of the Long March 7, with K2s as boosters.

The Long March 5 core will be built up from one or two H5 modules, with various combinations of K3 and K2 boosters. The largest version, Long March 5E, is intended to deliver 14 tons to geostationary orbit, its low-orbit payload unstated.

The description of Long March 7 corresponds with the mid-sized launcher that the academy detailed in 2007. The configuration displayed then had the two K3 core modules, four K2 boosters and a special 3-meter-dia. module, H3, that would presumably be an optional third stage for missions beyond low Earth orbit. But the range of payloads quoted for Long March 7, 10-20 tons, shows that it would be built with a variety of booster combinations. A single YF-100 would presumably provide second-stage propulsion.

The payload of the Long March 6 is unknown. China said last year that development of that launch vehicle had begun and that it would appear in 2013, a year before Long March 5. It is now described as a low-thrust launcher. The engine of the K2-2 second stage has not been stated, but the designation shows that it is fueled by kerosene, implying that it, too, is a YF-100. It would be unusual for a second stage to have the same engine as the first, since that would result in poor throw weight for the size of the rocket, though it would simplify production.

China's strict approach to modularity has been made possible by the shortcomings of its current technology, based on hydrazine-fueled engines in the earlier Long March launchers. Hydrazine is stored and ignited easily and thereby eases rocket design, but it is costly and toxic, and has much less energy for its weight than kerosene. In planning a future rocket family, China could therefore afford to begin with a clean sheet of paper.

The old hydrazine Long Marches may be needed after the new family goes into service, depending on the size of the gap between Long March 6 and 7.

Some established technology is being brought forward for Long March 7. Chinese media say the Long March 7 will be developed from the technology base of the Long March 2F, China's human-rated launcher. However, the new rocket's stated payload, far above the 8.4 tons of the Long March 2F, makes clear that the Chinese have introduced the YF-100.

Kerosene propulsion implies a complete redesign of the launcher body, since it demands liquid oxygen that needs cryogenic storage. Unless Long March 7 retains the hydrazine-engine core of older Long Marches, using YF-100s only in its boosters, it should be a fundamentally new launch vehicle.

The original core diameter of the old Long Marches has been kept in the K3 modules. Another non-Chinese rocket engineer suggests that, since Chinese industry has upgraded the equipment in its launchers over the past few years—renewing such systems as guidance and diagnostics, and installing new technology such as a health management system—it probably plans to move those items across to the Long March 7.

A Chinese industry executive confirms to Aviation Week that the K3 module has a new structure with new materials. The diameter has been kept for two reasons, he says, one being the original reason for its choice four decades ago: 3.35 meters is the most that will fit within the loading gauge of the Chinese railways. The second reason is that keeping the old diameter meant that costly tooling could also be retained.

The executive says one of the biggest challenges in the Long March 5 program has been building tools that can work on the greater diameter with adequate precision. That challenge would be even bigger with an 8-10-meter diameter.

The latest announcements have been reported by Beijing's Jinghua Times, Xinhua news agency and the English-language China Daily, whose content is intended for foreign consumption. The news coincides with the annual meeting of the National People's Congress, which is often an occasion for stirring patriotic announcements.

Confusingly, the Jinghua Times says the Long March 7 is needed because there is no other Chinese launcher with a capacity of 10-20 tons. But the two smallest versions of the Long March 5 could carry 10- and 18-ton payloads to low Earth orbit.

The Long March 5 program is at the engineering-model stage. Liang says the first full-diameter part, the bottom of a tank, has been welded together.

Long March 5 launchers will be used in the preparatory stage of a Moon landing, he says, implying that final execution of the manned landings will rely on the proposed Moon rocket.

Potentially, there will be a lot of Long March 5s. The Tianjin base will be able to build two a year when its first stage is completed in 2011 but capacity will rise to one a month. About 100,000 sq. meters of workspace is ready, with an initial investment of 1.5 billion yuan ($220 million). The final investment will be 10 billion yuan. "The launch base on Hainan [island] for big rockets is basically complete," adds Liang.

The Long March 5 will be needed to put a space station into orbit after an unknown number of Tiangong laboratories before 2020. The station's core module will have a mass of 20 tons. Qi Faren, who designed the Shenzhou manned spacecraft, says the Long March 5 will first be used to launch an 8-9-ton Fengyun weather satellite to geostationary orbit.

Next year a modified Long March 2F will launch Tiangong 1, which will be unmanned as a docking target before accommodating astronauts doing experiments. Beginning with that launch, greater reliability and accuracy will be needed from China's rockets, says the Jinghua Times. "Before Shenzhou 7, a launch failure meant only the failure of one mission," Liang tells the paper. "But from Tiangong 1 until Shenzhou 8, 9 and 10, one launch failure will imply the failure of the whole project."

That clearly excludes the use of new launch vehicles in the upcoming stages of the manned space program, but Xinhua says Long March 7 might be used in the Chang'e program of unmanned lunar probes.

[SpaceR]

Пресс-канцелярия Госсовета КНР опубликовала Белую книгу "Космическая индустрия Китая - 2011"
 . . .
Ракета-носитель "Чанчжэн-7" способна выводить 13,5 тонн на околоземную орбиту или [5,5 тонн на солнечно-синхронную орбиту высотой 700 километров

Пекин, 29 декабря /Синьхуа/ -- Ракета-носитель "Чанчжэн-7" способна выводить 13,5 тонн на околоземную орбиту или 5,5 тонн на солнечно-синхронную орбиту высотой 700 километров. Об этом сообщается в белой книге "Космическая индустрия Китая - 2011", опубликованной сегодня Пресс-канцелярией Госсовета КНР.

http://russian.news.cn/science/2011-12/29/c_131333336.htm

Какой-никакой, но прогресс: раньше говорилось о грузоподъемности в 13 тонн.

Если ещё не забывать, что именно эта РН в будущем должна запускать на орбиту и пилотируемые КК (а также и грузовые - к новой ОС), то не значит ли это, что в перспективе под неё появится и более массивный ПКК ?

[Salo]

http://russian.china.org.cn/news/txt/2011-12/29/content_24284279.htm

Белая книга
russian.china.org.cn 29-12-2011

В будущие 5 лет Китай осуществит первые полеты ракет-носителей "Чанчжэн-5", "Чанчжэн-6" и "Чанчжэн-7". Об этом говорится в белой книге "Космическая индустрия Китая - 2011", распространенной сегодня Пресс-канцелярией Госсовета КНР.[/size]

[Salo]

http://www.sinodefence.com/rocketry/changzheng7.asp

Changzheng 7

The Changzheng 7 (CZ-7, or Long March 7 in its English translation) is a medium-lift multirole space launch system currently under development at the China Academy of Launch Vehicle (CALT). It is intended as a successor for the existing Changzheng 2 and 4 series for both manned and unmanned launches. The first launch of the rocket is expected to take place in 2014~2015.

The basic variant CZ-7 consists of a 3.35m-diameter two-stage core-vehicle and four 2.25m-diameter strap-on liquid boosters. The first-stage of the core vehicle was based on the design of the 3.35m rocket module (K3-1), which was originally developed as a strap-on booster for the Changzheng 5 (CZ-5) heavy-lift launch vehicle. The module is powered by two YF-100 liquid rocket engines that use Kerosene as fuel and liquid oxygen (LOX) as oxidiser, giving a total thrust of 2,680kN (about 240 tonnes). The YF-100 was developed from the Russian RD-120 originally introduced in the 1980s.

The four strap-on liquid boosters were developed from the 2.25m-diameter strap-on booster (K2-1) for the CZ-5, each powered by a single YF-100 engine that gives a thrust of 1,340kN. The second-stage of the CZ-7's core vehicle will be newly-developed, also burning the LOX/Kerosene propellant.

The basic variant CZ-7 will be available in two versions: man-rated and cargo. The man-rated version has a payload capacity of 12,500kg to LEO and will replace the existing CZ-2F for the launch of the Shenzhou manned spacecraft. The cargo version has a payload capacity of 13,500kg to LEO, or 5,500kg to 700km SSO. It is likely going to replace the existing CZ-2C, CZ-2D, CZ-4B and CZ-4C for all satellite launches to LEO and polar orbit.

The CZ-7 can also be fitted with an upper (third) stage for increased payload to SSO and GTO. When it is fitted with an YZ-1 upper stage, the payload capacity to 700km SSO is increased to 8,000kg. When fitted with an YZ-2 upper stage, the launch vehicle can send 2,650kg payload to GTO. When fitted with a LOX/LH2 upper stage, the launch vehicle can send 7,000kg payload to GTO.


Last update: 8 January 2012

[Дмитрий В.]

http://www.sinodefence.com/rocketry/changzheng7.asp

Changzheng 7[/size]

Интересно, выходит, что CZ-7 может комплектоваться либо углеводородной ступенью К3-2, либо криогенной Н3. Тогда как в 2007 г. (см. картинку на предыдущей странице) эти ступени предлагалось использовать совместно (для высокоэнергетических миссий). :roll:

[SpaceR]

http://www.sinodefence.com/rocketry/changzheng7.asp

Changzheng 7[/size]

Интересно, выходит, что CZ-7 может комплектоваться либо углеводородной ступенью К3-2, либо криогенной Н3. Тогда как в 2007 г. (см. картинку на предыдущей странице) эти ступени предлагалось использовать совместно (для высокоэнергетических миссий). :roll:

:shock:  Где Вы такое нашли, Дмитрий ?
К3-2 указана для всех вариантов.

[Salo]

Тут вопрос, что такое не водородные верхние ступени YZ-1 и YZ-2?

[Дмитрий В.]

http://www.sinodefence.com/rocketry/changzheng7.asp

Changzheng 7[/size]

Интересно, выходит, что CZ-7 может комплектоваться либо углеводородной ступенью К3-2, либо криогенной Н3. Тогда как в 2007 г. (см. картинку на предыдущей странице) эти ступени предлагалось использовать совместно (для высокоэнергетических миссий). :roll:

:shock:  Где Вы такое нашли, Дмитрий ?
К3-2 указана для всех вариантов.

Из вышеприведенного сообщения я понял так, что третьи ступени YZ могут комплектоваться с К3-2 для выведения на низкие орбиты, и с криогенной для выведения на высокоэнергетические.