Long March 5

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Long March 5
长征五号遥二火箭转场.jpg
Long March 5 Y2 transporting to launch site
FunctionHeavy-lift launch vehicle
ManufacturerCALT
Country of originChina
Size
Height56.97 m (186.9 ft)
Diameter5 m (16 ft)
Mass854,500 kg (1,883,900 lb)
Stages2
Payload to LEO
Altitude200 km × 400 km (120 mi × 250 mi)
Mass25,000 kg (55,000 lb) [1][2]
Payload to GTO
Mass14,000 kg (31,000 lb) [3][4]
Payload to TLI
Mass8,800–9,400 kg (19,400–20,700 lb)
Payload to GEO
Mass6,000 kg (13,000 lb)
Payload to SSO
Altitude700 km (430 mi)
Mass15,000 kg (33,000 lb)
Payload to SSO
Altitude2,000 km (1,200 mi)
Mass6,700 kg (14,800 lb)
Payload to MEO
Mass13,000 kg (29,000 lb)
Payload to TMI
Mass6,000 kg (13,000 lb)
Associated rockets
FamilyLong March
Comparable
  • Ariane 5
  • Delta IV
  • Falcon 9
  • Proton-M
Launch history
StatusActive
Launch sitesWenchang, LC-1
Total launches
7
  • CZ-5: 5
  • CZ-5B: 2
Success(es)
6
  • CZ-5: 4
  • CZ-5B: 2
Failure(s)
1 (CZ-5)
First flight
  • Long March 5: 3 November 2016[5]
  • Long March 5B: 5 May 2020[6]
Last flightActive
Notable payloadsNext-generation crewed spacecraft, Chang'e 5, Tianwen 1, Tianhe
Boosters – CZ-5-300
No. boosters4
Length27.6 m (91 ft)
Diameter3.35 m (11.0 ft)
Gross mass156,600 kg (345,200 lb)
Propellant mass142,800 kg (314,800 lb)
Engines2 × YF-100d
ThrustSea level: 2,400 kN (540,000 lbf)
Vacuum: 2,680 kN (600,000 lbf)
Total thrust9,600 kN (2,200,000 lbf)
Specific impulseSea level: 300 s (2.9 km/s)
Vacuum: 335 s (3.29 km/s)
Burn time173 seconds
PropellantRP-1 / LOX
First stage – CZ-5-500
Length33.16 m (108.8 ft)
Diameter5 m (16 ft)
Gross mass186,900 kg (412,000 lb)
Propellant mass165,300 kg (364,400 lb)
Engines2 × YF-77
ThrustSea level: 1,020 kN (230,000 lbf)
Vacuum: 1,400 kN (310,000 lbf)
Specific impulseSea level: 320 s (3.1 km/s)
Vacuum: 430 s (4.2 km/s)
Burn time492 seconds
PropellantLH2 / LOX
Second stage – CZ-5-HO
Length11.54 m (37.9 ft)
Diameter5 m (16 ft)
Gross mass38,700 kg (85,300 lb)
Propellant mass32,000 kg (71,000 lb)
Engines2 × YF-75D
Thrust176.72 kN (39,730 lbf)
Specific impulse442 s (4.33 km/s)
Burn time700 seconds
PropellantLH2 / LOX
Third stage – YZ-2 (Optional)
Diameter3.8 m (12 ft)
Engines2 x YF-50D
Thrust6.5 kN (1,500 lbf)
Specific impulse316 s (3.10 km/s)
Burn time1105 seconds
PropellantN2O4 / UDMH

Long March 5 (LM-5; Chinese: 长征五号; pinyin: Chángzhēng wǔ hào), or Changzheng 5 (CZ-5), and also by its nickname "Pang-Wu" (胖五, "Fat-Five"),[7] 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.[8] It is the fifth iteration of the Long March rocket family, named for the Chinese Red Army's 1934–35 Long March, during the Chinese Civil War.

There are currently two CZ-5 variants: CZ-5 and CZ-5B. The maximum payload capacities are approximately 25,000 kg (55,000 lb) to low Earth orbit[9] (for CZ-5B) and approximately 14,000 kg (31,000 lb) to geostationary transfer orbit (for CZ-5).[10] 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.[11]

The first CZ-5 launched from Wenchang Space Launch Site on 3 November 2016 and placed its payload in a suboptimal but workable initial orbit.[12] 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, 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,[6] which require the lifting capabilities of a heavy lift launch vehicle.

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 launch vehicles with Chinese satellites, thereby circumventing the effects of U.S. embargo.[13]

China's main objective for initiating the new CZ-5 program in 2007 was in anticipation of its future requirement for larger LEO 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,[9] while launch was expected to occur at the new Wenchang Space Launch Site in the southernmost island province of Hainan.[9]

In July 2012, a new 1200 kN thrust LOX/kerosene engine to be used on the Long March 5 boosters was test-fired by China.[10][14]

The first photos of a CZ-5, undergoing tests, were released in March 2015.[15]

The first production CZ-5 was shipped from the port of Tianjin in North China to Wenchang Space Launch Site on Hainan Island on 20 September 2015 for launch rehearsals.[16]

The maiden flight of the CZ-5 was initially scheduled for 2014, but this subsequently slipped to 2016.[17]

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.[18]

Design and specifications[]

The chief designer of CZ-5 is Li Dong (Chinese: 李东) of the China Academy of Launch Vehicle Technology (CALT). The CZ-5 family include three primary modular core stages of 5.2-m diameter (maximum). The total length of the vehicle is 60.5 metres 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 metres to 3.35 metres 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. 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 (CNSA) commencing in 2005. Versions of both new engines, the YF-100 and the YF-77, had been successfully tested by mid-2007.[citation needed]

The CZ-5 series can deliver ~23 tonnes payload to LEO or ~14 tonnes payload to GTO (geosynchronous transfer orbit).[19] It will replace the CZ-2, CZ-3, and CZ-4 series in service, as well as provide new capabilities[clarification needed] not possessed by the previous Long March rocket family.[citation needed] 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,[20][21] but the light variants were cancelled in favor of CZ-6 and CZ-7 family launch vehicles.[citation needed]

Active[19][22]
Version CZ-5 CZ-5B
Boosters 4 × CZ-5-300, 2 × YF-100 4 × CZ-5-300, 2 × YF-100
First stage CZ-5-500, 2 × YF-77 CZ-5-500, 2 × YF-77
Second stage CZ-5-HO, 2 × YF-75D —
Third stage (optional) Yuanzheng-2 —
Thrust (at ground) 10620 KN 10620 KN
Launch weight 854,500 kg 837,500 kg [23]
Height 56.97 m 53.66 m
Payload (LEO 200 km) — ~25,000 kg [24]
Payload (GTO) 14,000 kg [24] —
Proposed[24][9]
Version CZ-5-200 CZ-5-320 CZ-5-522 CZ-5-540
Boosters — 2 × CZ-5-200, YF-100 2 × CZ-5-200, YF-100; 2 × CZ-5-300, 2 × YF-100 4 × CZ-5-200, YF-100
First stage CZ-5-200, YF-100 CZ-5-300, 2 × YF-100 CZ-5-500, 2 × YF-77 CZ-5-500, 2 × YF-77
Second stage CZ-YF-73, YF-73 CZ-5-KO, CZ-5-HO, 2 × YF-75D CZ-5-HO, 2 × YF-75D
Third stage (not used for LEO) — CZ-5-HO, YF-75 — —
Thrust (at ground) 1.34 MN 7.2 MN 8.24 MN 5.84 MN
Launch weight 82,000 kg 420,000 kg 630,000 kg 470,000 kg
Height (maximal) 33 m 55 m 58 m 53 m
Payload (LEO 200 km) 1500 kg 10,000 kg 20,000 kg 10,000 kg
Payload (GTO) — 6000 kg 11,000 kg 6000 kg

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.[25] The rocket finally launched at 12:43 UTC.[26]

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.[27][28] 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).[6]

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 in Hainan, China. CASC declared the mission a success within an hour of launch, after the communications satellite was placed in geostationary transfer orbit, thus marking the Long March 5 program's return to flight.[6]

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 anticipated that heavier low Earth orbit payloads, such as components of the future modular space station, would be carried by the 5B variant.

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 in Hainan Island. CASC declared the launch a success after the payloads were placed in low Earth orbit.[29][30]

The flight's secondary payload, the experimental cargo return craft, malfunctioned during its return to Earth on 6 May 2020.[31] 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.[32] 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 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.[33][a]

List of launches[]

For a more comprehensive list, see List of Long March launches.

Past launches[]

Flight № Date (UTC) Variant Launch site Upper stage Payload Orbit Result
Y1 3 November 2016
12:43 		5 Wenchang, LC-1 YZ-2 GEO Success
Y2 2 July 2017
11:23 		5 Wenchang, LC-1 None GTO Failure
Y3 27 December 2019
12:45 		5 Wenchang, LC-1 None GTO Success
5B-Y1 5 May 2020
10:00 [30][36] 		5B Wenchang, LC-1 None Next-generation crewed spacecraft LEO Success
Y4 23 July 2020
04:41 [37] 		5 Wenchang, LC-1 None Tianwen-1 Mars orbiter, lander and rover TMI Success
Y5 23 November 2020
20:30 [38] 		5 Wenchang, LC-1 None Chang'e 5, lunar sample-return TLI Success
5B-Y2 29 April 2021
03:23:15 [39] 		5B Wenchang, LC-1 None Tianhe, space station core module LEO Success[b]

Planned launches[]

Flight № Date (UTC) Variant Launch site Upper stage Payload Orbit Status
5B-Y3 May–June 2022[41] 5B Wenchang, LC-1 None Wentian, Chinese space station experiment module 1 LEO Planned
5B-Y4 August–September 2022[42] 5B Wenchang, LC-1 None Mengtian, Chinese space station experiment module 2 LEO Planned
2024[43][44] 5 Wenchang, LC-1 None Chang'e 6, lunar sample-return TLI Planned
2024[45] 5 Wenchang, LC-1 None Chang'e 7, Lunar Antarctic Comprehensive Exploration Mission TLI Planned
2024[46] 5B Wenchang, LC-1 None Xuntian, space telescope co-orbiting with the Chinese space station LEO Planned
2027[47] 5 Wenchang, LC-1 None , Scientific exploration test, lunar surface test

Verify the construction of lunar scientific research base

TLI Planned
2029[48] 5 Wenchang, LC-1 None Jupiter orbiter and interplanetary flyby probe Heliocentric orbit Planned

See also[]

  • Comparison of orbital launcher families
  • Comparison of orbital launch systems
  • Expendable launch system
  • Lists of rockets

Notes[]

  1. ^ A piece of debris up to 12-meters long, possibly originating from the reentry of the CZ-5B core stage from this launch, was found in the Ivory Coast's village of Mahounou on about 11 or 12 May 2020.[34][35]
  2. ^ The core stage of the CZ-5B Y2 mission attained enough velocity to remain in low but declining Earth orbit for over a week, as did the core stage for the CZ-5B Y1 mission; the CZ-5B Y2 mission's core stage eventually reentered Earth's atmosphere many kilometers above the Arabian Peninsula during the early morning hours of 9 May 2021 (UTC) with a possible debris impact location off the Maldives in the Indian Ocean.[40]

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External links[]

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