Long March (rocket family)

A Long March rocket or Changzheng rocket in Chinese pinyin 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, as "Chang Zheng" means "Long March" in Chinese pinyin. The rockets are named after the Long March of Chinese communist history.

History


China launched its first satellite, known as Dong Fang Hong 1 ("the East is Red"), into Earth orbit on its Long March space rocket on April 24, 1970, becoming the fifth nation to achieve independent launch capability. Early launches had a spotty record, focusing on launching of Chinese satellites. Starting in 1990, the 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 14, 1996, a similar failure during the launch of Intelsat 708. The rocket veered severely off course immediately after clearing the launch tower and crashed into a 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. Officials later blamed the failure on an "unexpected gust of wind" Xinhua News Agency initially reported 6 deaths and 57 injuries.

In the aftermath of the explosion, U.S. satellite makers shared information that allowed the Chinese to determine that the problem was in the welds. 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.

For thirteen years, between August 1996 and August 2009, 75 consecutive successful launches were conducted, ending with the launch of Palapa-D on August 31, 2009, which partially failed due to a third stage malfunction. On October 15, 2003, the Long March 2F rocket successfully launched the Shenzhou 5 spacecraft/orbiter carrying China's first astronaut into space; China thus became the third nation to send a person in space independently, after the Soviet Union/Russia and the United States. A Long March 2F launched the Shenzhou 6 with two astronauts on October 12, 2005. 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. On September 25, 2008, a Long March 2F launched Shenzhou 7, China's first three-man mission and first EVA mission.

On the June 11, 2013, a Long March 2F, launched from the Jiuquan Satellite Launch Center, put three astronauts into orbit for the Shenzhou 10 mission.

Payloads
The Long March is China's primary expendable launch system family. The Shenzhou spacecraft and Chang'e lunar orbiters are also launched on the Long March rocket. The maximum payload for LEO is 12,000 kg (CZ-3B), the maximum payload for GTO is 5,500 kg (CZ-3B/E). The next generation rocket – Long March 5 variants will offer more payload in the future.

Propellants
Long March 1's 1st and 2nd stage uses nitric acid and UDMH propellants, and its upper stage use a spin-stabilized solid rocket engine.

Long March 2, Long March 3, Long March 4, the main stages and associated liquid rocket boosters use dinitrogen tetroxide as the oxidizing agent and UDMH as the fuel. 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.

The new generation of Long March rocket family, Long March 5, and its derivations Long March 6, Long March 7 will use LOX and kerosene as core stage and liquid booster propellant, while LOX and LH2 in upper stages.

Variants
The Long March rockets are organized into several 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
 * Long March 6 rocket family
 * Long March 7 rocket family

Long March 9
Long March 9 (LM-9, CZ-9, or Changzheng 9) is a Chinese super-heavy carrier rocket that is currently in study. It is planned for a maximum payload capacity of at least 130,000 kg to LEO or at least 50,000 kg to Lunar Transfer Orbit.

Long March 11
The Long March 11 is a planned solid-fuel rocket being developed by China. It will apply China's largest solid-fuel rocket engine and was designed to meet the need to rapidly launch satellites in case of emergencies or disasters. Its first launch is planned before 2016.

Origins
The Long March 1 rocket is derived from earlier Chinese 2-stage IRBM DF-4, or Dong Feng 4 missile, and Long March 2, Long March 3, Long March 4 rocket families are derivatives of the Chinese 2-stage ICBMs DF-5, or Dong Feng 5 missile. 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.

The next generation of Long March rocket, Long March 5 rocket family will be a brand new design, while Long March 6 and Long March 7 can be seen as derivations because they use the liquid rocket booster design of Long March 5 to build small-to-mid capacity launch vehicles.

Launch sites
There are four launch centers in China. They are:
 * Jiuquan Satellite Launch Center
 * Taiyuan Satellite Launch Center
 * Wenchang Satellite Launch Center
 * Xichang 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. 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. The launch, on a Long March 3B rocket, was successfully conducted on July 5, 2007. A Chinese Long March 2D launched Venezuela's VRSS-1 (Venezuelan Remote Sensing Satellite 1) "Francisco de Miranda" on September 29, 2012.