Long March rocket

A Long March rocket (zh-stp|s=长征系列运载火箭|t=長征系列運載火箭|p=Chángzhēng xìliè yùnzài huǒjiàn) is any rocket in a family of expendable launch systems operated by the People's Republic of China. Development and design falls under the auspices of the China Academy of Launch Vehicle Technology. In English, the rockets are abbreviated as LM- for export and CZ- within China. The rockets are named after the Long March of Chinese communist history.

Payloads

The PRC launched its first satellite, known as Dong Fang Hong 1 ("the East is Red"), to Earth orbit on its own Long March space rocket on April 24, 1970, becoming the fifth nation to achieve independent launch capability. The Shenzhou spacecraft and Chang'e 1 lunar orbiter are also launched on the Long March rocket. The maximum payload for LEO is 9200 kg (CZ-2F), the maximum payload for GTO is 5200 kg (CZ-3B). The next generation rocketndash Long March 5 variants will offer more payload in the future.

Propellants

As of 2003, the main stages and the booster rockets of Long March rockets use storable propellants with UDMH as the fuel and dinitrogen tetroxide as the oxidizing agent. The upper stages (third stage) of Long March 3 rockets use YF-73 and YF-75 engines, using Liquid hydrogen (LH2) as the fuel and Liquid oxygen (LOX) as the oxidizer.

Specifications of Long March rocket family

The Long March rockets are organized into series:
* Long March 1 rocket family
* Long March 2 rocket family
* Long March 3 rocket family
* Long March 4 rocket family
* Long March 5 rocket family

Origins

The Long March rocket is related to early versions of the Dongfeng missile (note that Dongfeng is the generic Chinese name for all of its land ICBMs). However, like its counterparts in both the United States and in Russia, the differing needs of space rockets and strategic missiles have caused the development of space rockets and missiles to diverge. The main goal of a space rocket is to maximize payload, while for strategic missiles increased throw weight is much less important than the ability to launch quickly and to survive a first strike. This divergence has become clear in the next generation of Long March rockets which use cryogenic propellants in sharp contrast to the next generation of strategic missiles which are mobile and solid fuelled.

Launch sites

There are four launch centers in China. They are:
*Jiuquan Satellite Launch Center
*Xichang Satellite Launch Center
*Taiyuan Satellite Launch Center
*Wenchang Satellite Launch Center

Most of the commercial satellite launches of Long March vehicles have been from Xichang Satellite Launch Center, located in Xichang, Sichuan province. Wenchang Satellite Launch Center in Hainan province is under expansion and will be the main launch center for future commercial satellite launches. Long March launches also take place from the more military oriented Jiuquan Satellite Launch Center in Gansu province from which the manned Shenzhou spacecraft also launches. Taiyuan Satellite Launch Center is located in Shanxi province and focuses on the launches of Sun-synchronous orbit satellites.

Commercial launch services

China markets launch services under the China Great Wall Industry Corporation. [cite web |url=http://www.cgwic.com/about/index.html |title=About CGWIC |publisher=CGWIC] Its efforts to launch communications satellites were dealt a blow in the mid-1990s after the United States stopped issuing export licenses to companies to allow them to launch on Chinese launch vehicles out of fear that this would help China's military. In the face of this, Thales Alenia Space built the Chinasat-6B satellite with no components from the United States whatsoever. This allowed it to be launched on a Chinese launch vehicle without violating U.S. ITAR restrictions. [cite web |url=http://www.usatoday.com/tech/science/space/2007-07-06-china-launches-satellite_N.htm |title=China launches satellite despite restrictions |publisher=USA TODAY] The launch, on a Long March 3B rocket, was successfully conducted on 5 July 2007.

Launch history

Early launches had a spotty record, focusing on launching of Chinese satellites. Since 1990, Long March rocket entered the international market. However, several setbacks occurred during early 1990s. On January 26, 1995, a Long March 2E rocket veered off course two seconds after take-off from Xichang space center and exploded, killing at least six on the ground. On February 15, 1996, a similar failure during the launch of Intelsat 708 using a Long March 3B rocket resulted in an unknown number of casualties. [http://www.youtube.com/watch?v=y4oAQm4r5sI&mode=related&search=] The rocket veered severely off course right after clearing the launch tower and landed in a rural village. Following the disaster, foreign media were sequestered in a bunker for five hours while, some have alleged, the Chinese military attempted to 'clean up' the damage. The Chinese Xinhua News Agency eventually reported 57 deaths, but the extent of damage observed by foreign journalists whilst being whisked away from the disaster site suggested there may have been at least 200 and upwards of 500 killed. [cite news |first=John |last=Mintz |authorlink= |title=Missile Failures Led To Loral-China Link |page=A20 |url=http://www.washingtonpost.com/wp-srv/politics/special/campfin/stories/rocket061298.htm |work= |publisher=Washington Post |date=1998-06-12 |accessdate=2007-06-30 ] In the aftermath of the explosion, U.S. satellite makers shared information which allowed the Chinese to determine that the problem was in the welds. However, this sharing of information was later deemed illegal by the United States, and U.S. satellite maker Loral Space and Communications was fined $14 million by the U.S. government in 2002, while admitting no wrong-doing.Mintz, John, [http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2003/01/01/MN153988.DTL "2 U.S. space giants accused of aiding China Hughes, Boeing allegedly gave away missile technology illegally"] , "Washington Post", Jan. 1, 2003]

Since the improvements made after the 1996 accident, the reliability of the Long March rockets has been excellent, with zero failed launches. On October 15, 2003, the Long March 2F rocket successfully launched the "Shenzhou 5" spacecraft/orbiter carrying China's first astronaut into space, and on October 12, 2005, "Shenzhou 6" with two astronauts; China became the third nation to send man into space on its own, after the Soviet Union/Russia and the USA. On June 1, 2007, Long March rockets completed the 100th launch. On October 24, 2007, the Long March 3A successfully launched (18:05 GMT+8) the "Chang'e 1" lunar orbiting spacecraft from the Xichang Satellite Launch Center.

Planned launches

ee also

* China National Space Administration
* Shenzhou spacecraft
* Space program of China
* Tsien Hsue-shen

References

External links

* [http://www.astronautix.com/lvfam/lonmarch.htm Extensive information on the Chinese space program]
* [http://www.cgwic.com/index1.html China Great Wall Industry Corporation]
* [http://www.hq.nasa.gov/osf/2006/launch06.html NASA links - substitute year for other years]
* [http://www.youtube.com/watch?v=y4oAQm4r5sI&mode=related&search= Long March 3 accident]
* [http://www.geocities.com/CapeCanaveral/Launchpad/1921/engine.htm Long March Engines List]
* [http://www.braeunig.us/space/specs/lgmarch.htm Rocket and Space Technology]
* [http://www.geocities.com/CapeCanaveral/Launchpad/1921/launch.htm Chinese Launch Vehicle Overview]