Long March 5 (rocket family)
   HOME

TheInfoList



OR:

Long March 5 (LM-5; zh, s=长征五号 , p=Chángzhēng wǔ hào), or Changzheng 5 (CZ-5), and also by its nickname "''Pang-Wu''" (胖五, "''Fat-Five''"), is a Chinese heavy-lift launch vehicle developed by the China Academy of Launch Vehicle Technology (CALT). It is the first Chinese launch vehicle designed to use exclusively non- hypergolic liquid propellants. It is the fifth iteration of the Long March rocket family. There are currently two CZ-5 variants: CZ-5 and CZ-5B. The maximum payload capacities are approximately to low Earth orbit (for CZ-5B) and approximately to
geostationary transfer orbit A geosynchronous transfer orbit or geostationary transfer orbit (GTO) is a type of geocentric orbit. Satellite, Satellites that are destined for geosynchronous orbit, geosynchronous (GSO) or geostationary orbit (GEO) are (almost) always put into ...
(for CZ-5). As of 2021, a 3-core human-rated variant, referred to as CZ-5G, designed for manned moon mission, is under development; this variant will be capable of launching a crewed spacecraft into lunar orbit. The Long March 5 roughly matches the capabilities of American NSSL heavy-lift launch vehicles such as the Delta IV Heavy. It is currently the most powerful member of the Long March rocket family and the world's third most powerful orbital launch vehicle currently in operation, trailing the Falcon Heavy and Delta IV Heavy. The first CZ-5 launched from
Wenchang Space Launch Site The Wenchang Space Launch Site ( zh, 文昌航天发射场, links=no), located in Wenchang, Hainan, China, is a rocket launch site — one of the two spacecraft launch sites of Xichang Satellite Launch Center (the other site is in Xichang, ...
on 3 November 2016 and placed its payload in a suboptimal but workable initial orbit. The second CZ-5 rocket, launched on 2 July 2017, failed due to an engine problem in the first stage. After an interval of almost two and a half years, the Long March 5 vehicle's ''return to flight'' mission (third launch) successfully occurred on 27 December 2019 with the launch and placement of the experimental Shijian-20 communications satellite into
geostationary transfer orbit A geosynchronous transfer orbit or geostationary transfer orbit (GTO) is a type of geocentric orbit. Satellite, Satellites that are destined for geosynchronous orbit, geosynchronous (GSO) or geostationary orbit (GEO) are (almost) always put into ...
, thereby opening the way for the successful launch of Tianwen 1 Mars mission, lunar Chang'e 5 sample-return mission, and the modular space station, which require the lifting capabilities of a
heavy lift launch vehicle A heavy-lift launch vehicle, HLV or HLLV, is an orbital launch vehicle capable of lifting between (by NASA classification) or between (by Russian classification) into low Earth orbit (LEO).50t payloads" , operational heavy-lift launch vehicl ...
.


Launch Statistics


Development

Since 2010, Long March launches (all versions) have made up 15–25% of the global launch totals. Growing domestic demand for launch services has also allowed China's state launch provider to maintain a healthy manifest. Additionally, China had been able to secure some international launch contracts by offering package deals that
bundle Bundle or Bundling may refer to: * Bundling (packaging), the process of using straps to bundle up items Biology * Bundle of His, a collection of heart muscle cells specialized for electrical conduction * Bundle of Kent, an extra conduction pat ...
launch vehicles with Chinese satellites, thereby circumventing the effects of U.S. embargo. China's main objective for initiating the new CZ-5 program in 2007 was in anticipation of its future requirement for larger
LEO Leo or Léo may refer to: Acronyms * Law enforcement officer * Law enforcement organisation * ''Louisville Eccentric Observer'', a free weekly newspaper in Louisville, Kentucky * Michigan Department of Labor and Economic Opportunity Arts an ...
and GTO payload capacities during the next 20–30 years period. Formal approval of the Long March 5 program occurred in 2007 following two decades of feasibility studies when funding was finally granted by the Chinese government. At the time, the new rocket was expected to be manufactured at a facility in Tianjin, a coastal city near Beijing, while launch was expected to occur at the new
Wenchang Space Launch Site The Wenchang Space Launch Site ( zh, 文昌航天发射场, links=no), located in Wenchang, Hainan, China, is a rocket launch site — one of the two spacecraft launch sites of Xichang Satellite Launch Center (the other site is in Xichang, ...
in the southernmost island province of Hainan. In July 2012, a new thrust LOX/ kerosene engine to be used on the Long March 5 boosters was test-fired by China.Additional engine test-firings took place in July 2013. The first photos of a CZ-5, undergoing tests, were released in March 2015. The first production CZ-5 was shipped from the port of Tianjin in North China to
Wenchang Space Launch Site The Wenchang Space Launch Site ( zh, 文昌航天发射场, links=no), located in Wenchang, Hainan, China, is a rocket launch site — one of the two spacecraft launch sites of Xichang Satellite Launch Center (the other site is in Xichang, ...
on Hainan Island on 20 September 2015 for launch rehearsals. The maiden flight of the CZ-5 was initially scheduled for 2014, but this subsequently slipped to 2016.spaceflightnow
, accessed 30 September 2016
The final production and testing of the first CZ-5 rocket to be launched into orbit were completed at its Tianjin manufacturing facility on or about 16 August 2016 and the various segments of the rocket were shipped to the launch center on Hainan island shortly thereafter.


Design and specifications

The chief designer of CZ-5 is Li Dong () of the China Academy of Launch Vehicle Technology (CALT). The CZ-5 family includes three primary modular core stages of 5.2-m diameter (maximum). The vehicle's total length is 60.5 meters and its weight at launch is 643 tons, with a thrust of 833.8 tons. Boosters of various capabilities and diameters ranging from 2.25 meters to 3.35 meters would be assembled from three modular core stages and strap-on stages. The first stage and boosters would have a choice of engines that use different liquid rocket propellants: 1200 kN thrust LOX / kerosene engines or 1550 kN thrust LOX /
LH2 Liquid hydrogen (LH2 or LH2) is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must be cooled below its critical point of 33  K. However, for it to be in a fully liq ...
. The upper stage would use improved versions of the YF-75 engine. Engine development began in 2000–2001, with testing directed by the
China National Space Administration China National Space Administration (CNSA; ) is the government agency of the People's Republic of China that is responsible for civil space administration and international space cooperation, including organizing or leading foreign exchanges ...
(CNSA) commencing in 2005. Versions of both new engines, the
YF-100 The YF-100 is a Chinese liquid rocket engine burning LOX and kerosene in an oxidizer-rich staged combustion cycle. Development of the engine began in the 2000s, along with its sibling, the smaller YF-115, which would power the LM-6 and LM-7 u ...
and the YF-77, had been successfully tested by mid-2007. The CZ-5 series can deliver ~23 tonnes of payload to LEO or ~14 tonnes of payload to GTO (geosynchronous transfer orbit). It will replace the CZ-2, CZ-3, and CZ-4 series in service, as well as provide new capabilities not possessed by the previous Long March rocket family. The CZ-5 launch vehicle would consist of a 5.0-m diameter core stage and four 3.35-m diameter strap-on boosters, which would be able to send a ~22 tonne payload to low Earth orbit (LEO). Six CZ-5 variants were originally planned, but the light variants were cancelled in favor of CZ-6 and CZ-7 family launch vehicles. In 2021, it is revealed that a 3-core variant tentatively named CZ-5G is under development for potential crewed lunar missions. The vehicle will be equipped with 7 YF-100K/L LOX / kerosene engines at the core stage with two similar core stages acting as boosters, for a total of 21 YF-100 engines. The second stage will be equipped with 2 YF-100M LOX / kerosene engines and the third stage will be equipped with 3 YF-75E LOX /
LH2 Liquid hydrogen (LH2 or LH2) is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form. To exist as a liquid, H2 must be cooled below its critical point of 33  K. However, for it to be in a fully liq ...
engines. All stages share the same diameter.


Space debris concerns

The first stage of the Long March 5B variant, which can reach orbital velocity and weighs 21.6 tonnes, currently lacks the capability for controlled atmospheric re-entry, meaning that debris could cause damage on the ground upon re-entry. Without modification, it is expected all LEO launches of the Long March 5B will result in uncontrolled re-entries. The 5B is the specific variant in concern due to its unique LEO configuration. The core rocket stage (first stage) is launched directly into orbit, which also unusually serves as the upper stage to perform payload insertion. Typically, the rocket's first stage never reaches orbital velocity, while the smaller upper stage will usually burn up in the atmosphere during re-entry. However, Long March 5B's first and upper stage is combined into one, making the mitigation effort more difficult. Potential solutions include restarting engines during re-entry to reduce speed and collision probability, as the case for Long March 2D. China has also developed
grid fin Grid fins (or lattice fins) are a type of flight control surface used on rockets and bombs, sometimes in place of more conventional control surfaces, such as planar fins. They were developed in the 1950s by a team led by and used since the 197 ...
s on other Long March variants to steer stages during re-entry. However, Long March 5B has yet to demonstrate these capabilities. Although the probability of rocket debris hitting populated areas is mathematically minuscule, the scientistic fears the lax attitude of many countries could eventually result in casualties. The core stage of the Long March 5B-Y3 re-entered Earth's atmosphere on 30 July 2022, some debris may have survived re-entry and reached the ground. Before the launch of 5B-Y4, Liu Bing, deputy director-designer of the Long March 5B, told journalists that "an elaborative evaluation" was performed on the 5B to enable safe re-entry, though no details regarding the improved re-entry procedure were revealed.


Notable launches


First flight

The launch was planned to take place at around 10:00 UTC on 3 November 2016, but several issues, involving an oxygen vent and chilling of the engines, were detected during the preparation, causing a delay of nearly three hours. The final countdown was interrupted three times due to problems with the flight control computer and the tracking software. The rocket finally launched at 12:43 UTC.


Second flight

Its second launch on 2 July 2017 experienced an anomaly shortly after launch and was switched to an alternate, gentler trajectory. However, it was declared a failure 45 minutes into the flight. Investigations revealed the source of the second flight's failure to be located in one of the core stage's YF-77 engines (specifically, in the oxidizer's turbo-pump).


Third flight

The Y3 mission of the Long March 5 program was launched on 27 December 2019, at about 12:45 UTC from the
Wenchang Space Launch Site The Wenchang Space Launch Site ( zh, 文昌航天发射场, links=no), located in Wenchang, Hainan, China, is a rocket launch site — one of the two spacecraft launch sites of Xichang Satellite Launch Center (the other site is in Xichang, ...
in Hainan,
China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ...
. CASC declared the mission a success within an hour of launch, after the Shijian-20 communications satellite was placed in
geostationary transfer orbit A geosynchronous transfer orbit or geostationary transfer orbit (GTO) is a type of geocentric orbit. Satellite, Satellites that are destined for geosynchronous orbit, geosynchronous (GSO) or geostationary orbit (GEO) are (almost) always put into ...
, thus marking the Long March 5 program's return to flight.


Fourth flight (CZ-5B)

The fourth flight of the Long March 5 program also marked the debut of the CZ-5B variant. The CZ-5B variant is basically equivalent to the Long March 5 core stage with its four strapped-on liquid-fueled boosters; in place of the usual second stage of the base configuration, it is use to launch heavier low Earth orbit payloads, such as components of the Tiangong space station, would be carried by the 5B variant. The 5B variant may also be considered for launching constellation satellites in future with
Yuanzheng Yuanzheng () is a restartable upper stage developed by the China Academy of Launch Vehicle Technology (CALT) for the Long March rocket family. The Yuanzheng stage enables the Chinese launch vehicles to deploy payloads directly to high-energy or ...
upper stage. The first flight of the 5B variant ("Y1 mission") carried an uncrewed prototype of China's future deep space crewed spacecraft, and, as a secondary payload, the ''Flexible Inflatable Cargo Re-entry Vehicle''. The Y1 mission was launched on 5 May 2020, at 10:00 UTC from the
Wenchang Space Launch Site The Wenchang Space Launch Site ( zh, 文昌航天发射场, links=no), located in Wenchang, Hainan, China, is a rocket launch site — one of the two spacecraft launch sites of Xichang Satellite Launch Center (the other site is in Xichang, ...
in Hainan Island. CASC declared the launch a success after the payloads were placed in low Earth orbit. The flight's secondary payload, the experimental cargo return craft, malfunctioned during its return to Earth on 6 May 2020. Nevertheless, the return capsule of the prototype next-generation crewed spacecraft, the flight's primary payload, successfully landed in north China's Inner Mongolia Autonomous Region at 05:49 UTC, on 8 May 2020. The prototype spacecraft flew in orbit for two days and 19 hours and carried out a series of successful experiments and technological verifications. The Y1 mission's core stage may have been the most massive object to make an uncontrolled re-entry since the Soviet Union's
Salyut 7 Salyut 7 (russian: Салют-7; en, Salute 7) (a.k.a. DOS-6, short for Durable Orbital Station) was a space station in low Earth orbit from April 1982 to February 1991. It was first crewed in May 1982 with two crew via Soyuz T-5, and last vi ...
space station in 1991 and the United States' Skylab in 1979, excluding the failed controlled reentry of Space Shuttle ''Columbia'' over populated areas of the Continental United States in 2003.


List of launches


Past launches


Planned launches


See also

*
Comparison of orbital launcher families This article compares different orbital launcher families (although many launchers that are significantly different from other members of the same 'family' have their own separate entries). The article is organized into two tables: the first tabl ...
* Comparison of orbital launch systems *
Expendable launch system An expendable launch system (or expendable launch vehicle/ELV) is a launch vehicle that can be launched only once, after which its components are either destroyed during reentry or discarded in space. ELVs typically consist of several rocket sta ...
*
Lists of rockets There are several different types of rockets. The following articles contain lists of rockets by type: * List of missiles * List of orbital launch systems * List of sounding rockets * List of military rockets * List of rocket stages See also * C ...


Notes


References


External links

* {{Orbital launch systems Long March (rocket family) Vehicles introduced in 2016 2016 in technology 2016 in China