The Long March rocket family is a family of expendable launch system rockets operated by the China Aerospace Science and Technology Corporation.[1][2] The rockets are named after the Chinese Red Army's 1934–35 Long March military retreat during the Chinese Civil War.[3]
The Long March series has performed more than 600 launches, including missions to low Earth orbit, Sun-synchronous orbit, geostationary transfer orbit, and Earth-Moon transfer orbit. The Long March 2F is a human-rated vehicle which launches the Shenzhou craft. The Long March 5 has the greatest payload, at 25,000 kilograms to low Earth orbit, placing it in the heavy-lift launch vehicle class. It has launched the Tianwen-1 Mars probe and the Chang'e 6 and Chang'e 5 Moon probes. The Long March 10 is undergoing development and component testing as a launch vehicle for the Mengzhou and Lanyue crewed lunar vehicles.
The new-generation carrier rockets, Long March 5, 6, 7, 8, and 10 use a liquid oxygen with a liquid hydrogen or kerosene fuel, while the older Long March 2, 3, and 4 use the hypergolic mixture of unsymmetrical dimethylhydrazine and dinitrogen tetroxide.[1][2]
The early rockets in the family were derived from China's Dongfeng program of nuclear-capable ballistic missiles.[4] From 1988 to 1998, Long March rockets launched US commercial satellites, however failures carrying Apstar 2 and Intelsat 708 caused controversy in the US, resulting in such launches being prohibited under the US International Traffic in Arms Regulations.
Long March rockets typically launch commercial satellites from Xichang and Wenchang launch sites, military-related satellites and crewed craft from Jiuquan Satellite Launch Center, and Sun-synchronous satellties from Taiyuan Satellite Launch Center.
History
China used the Long March 1 rocket to launch its first satellite, Dong Fang Hong 1 (lit. "The East is Red 1"), into low Earth orbit on 24 April 1970, becoming the fifth nation to achieve independent launch capability. Early launches had an inconsistent record, focusing on the launching of Chinese satellites. The Long March 1 was quickly replaced by the Long March 2 family of launchers.
Origins
The Long March 1 rocket is derived from earlier Chinese 2-stage Intermediate-range ballistic missile (IRBM) DF-4, or Dong Feng 4 missile, and the Long March 2, Long March 3, Long March 4 rocket families are derivatives of the Chinese 2-stage Intercontinental ballistic missile (ICBM) 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 launch vehicle 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
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 25,000 kilograms (CZ-5B), the maximum payload for GTO is 14,000 kg (CZ-5). The next generation rocket Long March 5 variants will offer more payload in the future.
Propellants
Long March 1's 1st and 2nd stage used nitric acid and unsymmetrical dimethylhydrazine (UDMH) propellants, and its upper stage used 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 (N2O4) 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, Long March 8, and Long March 10 use non-toxic LOX/kerosene and LOX/LH2 liquid propellants (except in some upper stages where UDMH/N2O4 continues to be used).
Long March 9 is being developed as a LOX/CH4, or methalox, rocket.
Long March 11 is a solid-fuel rocket.
Members
Timeline bars start at first launch (rather than start of development).
The Long March rockets are organized into several series:
The Long March 5, 6 and 7 are a newer generation of rockets sharing the new 1200 kN class YF-100 engines, which burns RP-1 / LOX, unlike earlier 2, 3 and 4 series which uses more expensive and dangerous N2O4 / UDMH propellants.[19] The 5 series is a heavy-lift launch vehicle, with a capacity of 25,000 kg to LEO, while the 6 series is a small-lift launch vehicle with a capacity of 1,500 kg to LEO, and the 7 series is a medium-lift launch vehicle, with a capacity of 14,000 kg to LEO.
The Long March 10 and 12 series use the uprated YF-100K engines.
The Long March 10A is a partially-reusable crewed-rated rocket designed for LEO missions currently under development; the Long March 9 is initially designed to be partially reusable before becoming a fully reusable launcher.
- Long March 1
- Long March 2
- Long March 3
Launch sites
There are four launch centers in China. They are:
Most of the commercial satellite launches of Long March vehicles have been from Xichang Satellite Launch Center, located in Xichang, Sichuan province. Wenchang Spacecraft Launch Site 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 crewed Shenzhou spacecraft also launches. Taiyuan Satellite Launch Center is located in Shanxi province and focuses on the launches of Sun-synchronous orbit (SSO) satellites.
On 5 June 2019, China launched a Long March 11 rocket from a mobile launch platform in the Yellow Sea.[46]
- Jiuquan Satellite Launch Center
- Taiyuan Satellite Launch Center
- Wenchang Spacecraft Launch Site
Commercial launch services
China markets launch services under the China Aerospace Science and Technology Corporation (China Great Wall Industry Corporation).[47] 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 United States International Traffic in Arms Regulations (ITAR) restrictions.[48] The launch, on a Long March 3B rocket, was successfully conducted on 5 July 2007.
A Chinese Long March 2D launched VRSS-1 (Venezuelan Remote Sensing Satellite-1) of Venezuela, "Francisco de Miranda" on 29 September 2012.
See also
- China National Space Administration
- Space program of China
- Comparison of orbital launchers families
- Comparison of orbital launch systems
External links
References
- 长征_中国航天科技集团有限公司 China Aerospace Science and Technology Corporation spacechina.com, retrieved 2022-05-28^
- Launch Vehicles China Aerospace Science and Technology Corporation, May 28, 2022^
- 我国运载火箭为什么以"长征"命名-新华网 Xinhua News Agency, retrieved 2022-05-28