Long March 3B


The Long March 3B, also known as the CZ-3B and LM-3B, is a Chinese orbital carrier rocket. Introduced in 1996, it is launched from Launch Area 2 and 3 at the Xichang Satellite Launch Center in Sichuan. A three-stage rocket with four strap-on liquid rocket boosters, it is currently the second most powerful member of the Long March rocket family after the Long March 5 and the heaviest of the Long March 3 rocket family, and is mainly used to place communications satellites into geosynchronous orbits.
An enhanced version, the Long March 3B/E or G2, was introduced in 2007 to increase the rocket's GTO cargo capacity and lift heavier GEO communications satellites. The Long March 3B also served as the basis for the medium-capacity Long March 3C, which was first launched in 2008.
, the Long March 3B and 3B/E have conducted 65 successful launches, plus two failures and two partial failures, giving them a success rate of.

History

The development of the Long March 3B began in 1986 to meet the needs of the international GEO communications satellite market. During its maiden flight, on 14 February 1996 carrying the Intelsat 708 satellite, the rocket suffered a guidance failure two seconds into the flight and destroyed a nearby town, killing at least six people, but outside estimates suggest that anywhere between 200 and 500 people might have been killed. However, the author of the report later ruled out large casualties, because evidence suggest that the crash site was evacuated before the launch.
The Long March 3B and 3B/E rockets conducted ten successful launches between 1997 and 2008.
In 1997, the Agila 2 satellite was forced to use onboard propellant to reach its correct orbit because of poor injection accuracy on the part of its Long March 3B launch vehicle. In 2009, a Long March 3B partially failed during launch due to a third stage anomaly, which resulted in the Palapa-D satellite reaching a lower orbit than planned. Nonetheless, the satellite was able to maneuver itself into the planned orbit. The Long March 3B and its variants remain in active use as of 2020, having conducted a total of 26 consecutive successful launches, since 19 June 2017 until now.
In December 2013, a Long March 3B/E successfully lifted Chang'e 3, China's first Lunar lander and rover into the projected lunar-transfer orbit.
In April 2020, the third stage of the Long March 3B/E failed during a Palapa-N1 communications satellite mission; this was the first total failure of the Long March 3B/E.

Design and variants

The Long March 3B is based on the Long March 3A as its core stage, with four liquid boosters strapped on the first stage. It has an LEO cargo capacity of and a GTO capacity is.

Long March 3B/E

The Long March 3B/E, also known as 3B/G2, is an enhanced variant of the Long March 3B, featuring an enlarged first stage and boosters, increasing its GTO payload capacity to. Its maiden flight took place on 13 May 2007, when it successfully launched Nigeria's NigComSat-1, the first African geosynchronous communications satellite. In 2013, it successfully launched China's first lunar lander Chang'e 3 and lunar rover Yutu.
Since 2015, the Long March 3B and 3C can optionally accommodate a YZ-1 upper stage, which has been used to carry dual launches or BeiDou navigation satellites into medium-Earth orbit.

Long March 3C

A modified version of the Long March 3B, the Long March 3C, was developed in the mid-1990s to bridge the gap in payload capacity between the Long March 3B and 3A. It is almost identical to the Long March 3B, but has two boosters instead of four, giving it a reduced GTO payload capacity of. Its maiden launch took place on 25 April 2008.

List of launches

Flight numberDate Launch siteVersionPayloadOrbitResult
114 February 1996
19:01		LA-2, XSLC3BIntelsat 708GTO
219 August 1997
17:50		LA-2, XSLC3BAgila-2GTO
316 October 1997
19:13		LA-2, XSLC3BAPStar 2RGTO
430 May 1998
10:00		LA-2, XSLC3BChinastar 1GTO
518 July 1998
09:20		LA-2, XSLC3BSinoSat 1GTO
612 April 2005
12:00		LA-2, XSLC3BAPStar 6GTO
728 October 2006
16:20		LA-2, XSLC3BSinoSat 2GTO
813 May 2007
16:01		LA-2, XSLC3B/ENigComSat-1GTO
95 July 2007
12:08		LA-2, XSLC3BChinaSat 6BGTO
109 June 2008
12:15		LA-2, XSLC3BChinaSat 9GTO
1129 October 2008
16:53		LA-2, XSLC3B/EVenesat-1GTO
1231 August 2009
09:28		LA-2, XSLC3BPalapa-DGTO
134 September 2010
16:14		LA-2, XSLC3B/ESinoSat 6GTO
1420 June 2011
16:13		LA-2, XSLC3B/EChinaSat 10GTO
1511 August 2011
16:15		LA-2, XSLC3B/EPaksat-1RGTO
1618 September 2011
16:33		LA-2, XSLC3B/EChinaSat 1AGTO
177 October 2011
08:21		LA-2, XSLC3B/EEutelsat W3CGTO
1819 December 2011
16:41		LA-2, XSLC3B/ENigComSat-1RGTO
1931 March 2012
10:27		LA-2, XSLC3B/EAPStar 7GTO
2029 April 2012
20:50		LA-2, XSLC3BCompass-M3
Compass-M4		MTO
2126 May 2012
15:56		LA-2, XSLC3B/EChinaSat 2AGTO
2218 September 2012
19:10		LA-2, XSLC3BCompass-M5
Compass-M6		MTO
2327 November 2012
10:13		LA-2, XSLC3B/EChinaSat 12GTO
241 May 2013
16:06		LA-2, XSLC3B/EChinaSat 11GTO
251 December 2013
17:30		LA-2, XSLC3B/EChang'e 3LTO
2620 December 2013
16:42		LA-2, XSLC3B/ETúpac Katari 1GTO
2725 July 2015
12:29		LA-2, XSLC3B/E + YZ-1BeiDou M1-S
BeiDou M2-S		MEO
2812 September 2015
15:42		LA-2, XSLC3B/ETJSW-1GTO
2929 September 2015
23:13		LA-3, XSLC3B/EBeiDou I2-SGTO
3016 October 2015
16:16		LA-2, XSLC3B/EAPStar 9GTO
313 November 2015
16:25		LA-3, XSLC3B/EChinaSat 2CGTO
3220 November 2015
16:07		LA-2, XSLC3B/ELaoSat-1GTO
339 December 2015
16:46		LA-3, XSLC3B/EChinaSat 1CGTO
3428 December 2015
16:04		LA-2, XSLC3B/EGaofen 4GTO
3515 January 2016
16:57		LA-3, XSLC3B/EBelintersat-1GTO
365 August 2016
16:22		LA-3, XSLC3B/ETiantong-1-01GTO
3710 December 2016
16:11		LA-3, XSLC3B/EFengyun-4AGTO
385 January 2017
15:18		LA-2, XSLC3B/ETJSW-2GTO
3912 April 2017
11:04		LA-2, XSLC3B/EShijian 13GTO
4019 June 2017
16:11		LA-2, XSLC3B/EChinasat 9AGTO
415 November 2017
11:45		LA-2, XSLC3B/E + YZ-1BeiDou-3 M1
BeiDou-3 M2		MEO
4210 December 2017
16:40		LA-2, XSLC3B/EAlcomsat-1GTO
4311 January 2018
23:18		LA-2, XSLC3B/E + YZ-1BeiDou-3 M7
BeiDou-3 M8		MEO
4412 February 2018
05:03		LA-2, XSLC3B/E + YZ-1BeiDou-3 M3
BeiDou-3 M4		MEO
4529 March 2018
17:56		LA-2, XSLC3B/E + YZ-1BeiDou-3 M9
BeiDou-3 M10		MEO
463 May 2018
16:06		LA-2, XSLC3B/EApstar 6CGTO
4729 July 2018
01:48		LA-3, XSLC3B/E + YZ-1BeiDou-3 M5
BeiDou-3 M6		MEO
4824 August 2018
23:52		LA-3, XSLC3B/E + YZ-1BeiDou-3 M11
BeiDou-3 M12		MEO
4919 September 2018
14:07		LA-3, XSLC3B/E + YZ-1BeiDou-3 M13
BeiDou-3 M14		MEO
5015 October 2018
04:23		LA-3, XSLC3B/E + YZ-1BeiDou-3 M15
BeiDou-3 M16		MEO
511 November 2018
15:57		LA-2, XSLC3B/EBeiDou-3 G1GTO
5218 November 2018
18:07		LA-3, XSLC3B/E + YZ-1BeiDou-3 M17
BeiDou-3 M18		MEO
537 December 2018
18:23		LA-2, XSLC3B/EChang'e 4LTO
5410 January 2019
17:11		LA-2, XSLC3B/EChinaSat 2DGTO
559 March 2019
16:28		LA-3, XSLC3B/EChinaSat 6CGTO
5631 March 2019
15:51		LA-2, XSLC3B/ETianlian 2-01GTO
5720 April 2019
14:41		LA-3, XSLC3B/EBeiDou-3 I1GTO
5824 June 24, 2019
18:09		LA-3, XSLC3B/EBeiDou-3 I2GTO
5919 August 2019
12:03		LA-2, XSLC3B/EChinaSat 18GTO
6022 September 2019
21:10		LA-2, XSLC3B/E + YZ-1BeiDou-3 M23
BeiDou-3 M24		MEO
6117 October 2019
15:21		LA-3, XSLC3B/ETJSW-4GTO
624 November 2019
17:43		LA-2, XSLC3B/EBeiDou-3 I3GTO
6323 November 2019
00:55		LA-3, XSLC3B/E + YZ-1BeiDou-3 M21
BeiDou-3 M22		MEO
6416 December 2019
07:22		LA-3, XSLC3B/E + YZ-1BeiDou-3 M19
BeiDou-3 M20		MEO
657 January 2020
15:20		LA-2, XSLC3B/ETJSW-5GTO
669 March 2020
11:55		LA-2, XSLC3B/EBeiDou-3GTO
679 April 2020
11:46		LA-2, XSLC3B/EPalapa-N1 GTO
6823 June 2020
01:43		LA-2, XSLC3B/EBeiDou-3GTO
699 July 2020
12:11		XSLC, LA-23B/EApstar 6DGTO

Flight mishaps

Intelsat 708 launch failure

On 14 February 1996, the launch of the first Long March 3B with Intelsat 708 failed just after liftoff when the launch vehicle veered off course and exploded when it hit the ground at T+23 seconds. One person on the ground was killed by the explosion. The cause of the accident was traced to short-circuiting of the vehicle's guidance platform at liftoff. The number of casualties is debated and unclear even decades after the accident. The Chinese official death toll is usually of the order of few casualties, whereas some estimates place the number of people dead to a few hundred.
The participation of Space Systems/Loral in the accident investigation caused great political controversy in the United States since the information provided during the accident investigation would help China improve its rockets and ballistic missiles. The U.S. Congress reclassified satellite technology as a munition and placed it back under the restrictive International Traffic in Arms Regulations in 1998. No license to launch United States spacecraft on Chinese rockets has been approved by the U.S. State Department since then, and an official at the Bureau of Industry and Security emphasized in 2016 that "no U.S.-origin content, regardless of significance, regardless of whether it's incorporated into a foreign-made item, can go to China".

Palapa-D partial launch failure

On 31 August 2009, during the launch of Palapa-D, the third stage engine under-performed and placed the satellite into a lower than planned orbit. The satellite was able to make up the performance shortfall using its own engine and reach geosynchronous orbit, but with its lifetime shortened to 10.5 years from the originally projected 15-16 years. The investigation found that the failure was due to burn-through of the engine's gas generator, and that "the most likely cause of the burn-through was a foreign matter or humidity-caused icing in the engine's liquid-hydrogen injectors".

ChinaSat-9A partial launch failure

On 19 June 2017, a Long March 3B/E mission carrying ChinaSat-9A ended in partial failure. Officials did not release details regarding the status of the mission for at least 4 hours after liftoff. Two weeks later, on 7 July 2017, officials confirmed that the mission had been anomalous, with Space Daily reporting that "an anomaly was found on the carrier rocket's rolling control thruster, part of the attitude control engine, during the third gliding phase". The failure in the rocket's third stage left the payload in a lower than intended orbit, and the payload was forced to spend two weeks reaching its intended orbit under its own power.

Palapa-N1 (Nusantara Dua) launch failure

On 9 April 2020, a Long March 3B launcher failed after lifting off from the Xichang Satellite Launch Center in the southwestern Sichuan province at 11:46 UTC during the launch of an Indonesian communications satellite, Palapa-N1 of a mass of 5500 kg and was expected to enter service in geostationary orbit at 113° East, replacing the Palapa-D satellite. But one of the two YF-75 third stage engines appeared failed to ignite, preventing the Palapa-N1 satellite to reach orbit. Wreckage from the third stage and the Palapa-N1 spacecraft re-entered the atmosphere, leading to sightings of fiery debris in the skies over Guam. With the Long March 3B failure, Chinese rockets have faltered on two missions in less than a month. A Long March 7A rocket failed to place a satellite in orbit on 16 March 2020 after taking off from the Wenchang Spacecraft Launch Site on Hainan Island, located in southern China. After two Chinese launch failures in less than a month, further Chinese launches will be likely delayed until it is sure that the quality control is satisfactory.