# Long March 3B

The Long March 3B (Chinese: 长征三号乙; pinyin: Chángzhēng sānhàoyǐ), also known as the CZ-3B and LM-3B, is a Chinese orbital launch vehicle. 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 the heaviest variant of the Long March 3 rocket family, and is mainly used to place communications satellites and navigation satellites into geosynchronous orbits.
An enhanced version, the Long March 3B/E or G2, was introduced in 2007 to increase the rocket's geostationary transfer orbit (GTO) cargo capacity and lift heavier geosynchronous orbit (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.
As of 9 March 2025, the Long March 3B, 3B/E and 3B/G5 have conducted 101 successful launches, plus 2 failures and 2 partial failures, accumulating a success rate of 96.2%. It is the first Long March series rocket to accumulate 100 orbital launches.

## 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 January 2021, having conducted a total of 26 consecutive successful launches, since 19 June 2017 until 9 March 2020.
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 a low Earth orbit (LEO) cargo capacity of 11,200 kg (24,700 lb) and a GTO capacity is 5,100 kg (11,200 lb).

### 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 5,500 kg (12,100 lb). 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 (MEO).

### 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 3,800 kg (8,400 lb). Its maiden launch took place on 25 April 2008.

## Launch statistics

* Failure
* Partial failure
* Success
* Planned

## List of launches

| Flight number | Serial number | Date (UTC) | Launch site | Version | Payload | Orbit | Result |
| 1 | Y1 | 14 February 1996 19:01 | XSLC, LA-2 | 3B | Intelsat 708 | GTO | Failure |
| 2 | Y2 | 19 August 1997 17:50 | XSLC, LA-2 | 3B | Agila-2 | GTO | Success |
| 3 | Y3 | 16 October 1997 19:13 | XSLC, LA-2 | 3B | APStar 2R | GTO | Success |
| 4 | Y5 | 30 May 1998 10:00 | XSLC, LA-2 | 3B | Chinastar 1 | GTO | Success |
| 5 | Y4 | 18 July 1998 09:20 | XSLC, LA-2 | 3B | SinoSat 1 | GTO | Success |
| 6 | Y6 | 12 April 2005 12:00 | XSLC, LA-2 | 3B | APStar 6 | GTO | Success |
| 7 | Y7 | 28 October 2006 16:20 | XSLC, LA-2 | 3B | SinoSat 2 | GTO | Success |
| 8 | Y9 | 13 May 2007 16:01 | XSLC, LA-2 | 3B/E | NigComSat-1 | GTO | Success |
| 9 | Y10 | 5 July 2007 12:08 | XSLC, LA-2 | 3B | ChinaSat 6B | GTO | Success |
| 10 | Y11 | 9 June 2008 12:15 | XSLC, LA-2 | 3B | ChinaSat 9 | GTO | Success |
| 11 | Y12 | 29 October 2008 16:53 | XSLC, LA-2 | 3B/E | Venesat-1 | GTO | Success |
| 12 | Y8 | 31 August 2009 09:28 | XSLC, LA-2 | 3B | Palapa-D | GTO | Partial Failure |
| 13 | Y13 | 4 September 2010 16:14 | XSLC, LA-2 | 3B/E | SinoSat 6 | GTO | Success |
| 14 | Y20 | 20 June 2011 16:13 | XSLC, LA-2 | 3B/E | ChinaSat 10 | GTO | Success |
| 15 | Y19 | 11 August 2011 16:15 | XSLC, LA-2 | 3B/E | Paksat-1R | GTO | Success |
| 16 | Y16 | 18 September 2011 16:33 | XSLC, LA-2 | 3B/E | ChinaSat 1A | GTO | Success |
| 17 | Y18 | 7 October 2011 08:21 | XSLC, LA-2 | 3B/E | Eutelsat W3C | GTO | Success |
| 18 | Y21 | 19 December 2011 16:41 | XSLC, LA-2 | 3B/E | NigComSat-1R | GTO | Success |
| 19 | Y22 | 31 March 2012 10:27 | XSLC, LA-2 | 3B/E | APStar 7 | GTO | Success |
| 20 | Y14 | 29 April 2012 20:50 | XSLC, LA-2 | 3B | Compass-M3 Compass-M4 | MEO | Success |
| 21 | Y17 | 26 May 2012 15:56 | XSLC, LA-2 | 3B/E | ChinaSat 2A | GTO | Success |
| 22 | Y15 | 18 September 2012 19:10 | XSLC, LA-2 | 3B | Compass-M5 Compass-M6 | MEO | Success |
| 23 | Y24 | 27 November 2012 10:13 | XSLC, LA-2 | 3B/E | ChinaSat 12 | GTO | Success |
| 24 | Y25 | 1 May 2013 16:06 | XSLC, LA-2 | 3B/E | ChinaSat 11 | GTO | Success |
| 25 | Y23 | 1 December 2013 17:30 | XSLC, LA-2 | 3B/E | Chang'e 3 | TLI | Success |
| 26 | Y27 | 20 December 2013 16:42 | XSLC, LA-2 | 3B/E | Túpac Katari 1 | GTO | Success |
| 27 | Y26 | 25 July 2015 12:29 | XSLC, LA-2 | 3B/E + YZ-1 | BeiDou M1-S BeiDou M2-S | MEO | Success |
| 28 | Y32 | 12 September 2015 15:42 | XSLC, LA-2 | 3B/E | TJS-1 | GTO | Success |
| 29 | Y33 | 29 September 2015 23:13 | XSLC, LA-3 | 3B/E | BeiDou I2-S | GTO | Success |
| 30 | Y36 | 16 October 2015 16:16 | XSLC, LA-2 | 3B/E | APStar 9 | GTO | Success |
| 31 | Y34 | 3 November 2015 16:25 | XSLC, LA-3 | 3B/E | ChinaSat 2C | GTO | Success |
| 32 | Y38 | 20 November 2015 16:07 | XSLC, LA-2 | 3B/E | LaoSat-1 | GTO | Success |
| 33 | Y31 | 9 December 2015 16:46 | XSLC, LA-3 | 3B/E | ChinaSat 1C | GTO | Success |
| 34 | Y37 | 28 December 2015 16:04 | XSLC, LA-2 | 3B/E | Gaofen 4 | GTO | Success |
| 35 | Y29 | 15 January 2016 16:57 | XSLC, LA-3 | 3B/E | Belintersat-1 | GTO | Success |
| 36 | Y35 | 5 August 2016 16:22 | XSLC, LA-3 | 3B/E | Tiantong 1-01 | GTO | Success |
| 37 | Y42 | 10 December 2016 16:11 | XSLC, LA-3 | 3B/E | Fengyun-4A | GTO | Success |
| 38 | Y39 | 5 January 2017 15:18 | XSLC, LA-2 | 3B/E | TJS-2 | GTO | Success |
| 39 | Y43 | 12 April 2017 11:04 | XSLC, LA-2 | 3B/E | Shijian 13 | GTO | Success |
| 40 | Y28 | 19 June 2017 16:11 | XSLC, LA-2 | 3B/E | Chinasat 9A | GTO | Partial failure |
| 41 | Y46 | 5 November 2017 11:45 | XSLC, LA-2 | 3B/E + YZ-1 | BeiDou-3 M1 BeiDou-3 M2 | MEO | Success |
| 42 | Y40 | 10 December 2017 16:40 | XSLC, LA-2 | 3B/E | Alcomsat-1 | GTO | Success |
| 43 | Y45 | 11 January 2018 23:18 | XSLC, LA-2 | 3B/E + YZ-1 | BeiDou-3 M7 BeiDou-3 M8 | MEO | Success |
| 44 | Y47 | 12 February 2018 05:03 | XSLC, LA-2 | 3B/E + YZ-1 | BeiDou-3 M3 BeiDou-3 M4 | MEO | Success |
| 45 | Y48 | 29 March 2018 17:56 | XSLC, LA-2 | 3B/E + YZ-1 | BeiDou-3 M9 BeiDou-3 M10 | MEO | Success |
| 46 | Y55 | 3 May 2018 16:06 | XSLC, LA-2 | 3B/E | Apstar 6C | GTO | Success |
| 47 | Y49 | 29 July 2018 01:48 | XSLC, LA-3 | 3B/E + YZ-1 | BeiDou-3 M5 BeiDou-3 M6 | MEO | Success |
| 48 | Y50 | 24 August 2018 23:52 | XSLC, LA-3 | 3B/E + YZ-1 | BeiDou-3 M11 BeiDou-3 M12 | MEO | Success |
| 49 | Y51 | 19 September 2018 14:07 | XSLC, LA-3 | 3B/E + YZ-1 | BeiDou-3 M13 BeiDou-3 M14 | MEO | Success |
| 50 | Y52 | 15 October 2018 04:23 | XSLC, LA-3 | 3B/E + YZ-1 | BeiDou-3 M15 BeiDou-3 M16 | MEO | Success |
| 51 | Y41 | 1 November 2018 15:57 | XSLC, LA-2 | 3B/E | BeiDou-3 G1 | GTO | Success |
| 52 | Y53 | 18 November 2018 18:07 | XSLC, LA-3 | 3B/E + YZ-1 | BeiDou-3 M17 BeiDou-3 M18 | MEO | Success |
| 53 | Y30 | 7 December 2018 18:23 | XSLC, LA-2 | 3B/E | Chang'e 4 | TLI | Success |
| 54 | Y56 | 10 January 2019 17:11 | XSLC, LA-2 | 3B/E | ChinaSat 2D | GTO | Success |
| 55 | Y54 | 9 March 2019 16:28 | XSLC, LA-3 | 3B/E | ChinaSat 6C | GTO | Success |
| 56 | Y44 | 31 March 2019 15:51 | XSLC, LA-2 | 3B/E | Tianlian 2-01 | GTO | Success |
| 57 | Y59 | 20 April 2019 14:41 | XSLC, LA-3 | 3B/E | BeiDou-3 I1 | GTO | Success |
| 58 | Y60 | 24 June, 2019 18:09 | XSLC, LA-3 | 3B/E | BeiDou-3 I2 | GTO | Success |
| 59 | Y58 | 19 August 2019 12:03 | XSLC, LA-2 | 3B/E | ChinaSat 18 | GTO | Success |
| 60 | Y65 | 22 September 2019 21:10 | XSLC, LA-2 | 3B/E + YZ-1 | BeiDou-3 M23 BeiDou-3 M24 | MEO | Success |
| 61 | Y57 | 17 October 2019 15:21 | XSLC, LA-3 | 3B/E | TJS-4 | GTO | Success |
| 62 | Y61 | 4 November 2019 17:43 | XSLC, LA-2 | 3B/E | BeiDou-3 I3 | GTO | Success |
| 63 | Y66 | 23 November 2019 00:55 | XSLC, LA-3 | 3B/E + YZ-1 | BeiDou-3 M21 BeiDou-3 M22 | MEO | Success |
| 64 | Y67 | 16 December 2019 07:22 | XSLC, LA-3 | 3B/E + YZ-1 | BeiDou-3 M19 BeiDou-3 M20 | MEO | Success |
| 65 | Y62 | 7 January 2020 15:20 | XSLC, LA-2 | 3B/E | TJS-5 | GTO | Success |
| 66 | Y69 | 9 March 2020 11:55 | XSLC, LA-2 | 3B/E | BeiDou-3 G2 | GTO | Success |
| 67 | Y71 | 9 April 2020 11:46 | XSLC, LA-2 | 3B/E | Palapa-N1 (Nusantara Dua) | GTO | Failure |
| 68 | Y68 | 23 June 2020 01:43 | XSLC, LA-2 | 3B/E | BeiDou-3 G3 | GTO | Success |
| 69 | Y64 | 9 July 2020 12:11 | XSLC, LA-2 | 3B/E | Apstar 6D | GTO | Success |
| 70 | Y63 | 11 October 2020 16:57 | XSLC, LA-2 | 3B/E | Gaofen-13 | GTO | Success |
| 71 | Y73 | 12 November 2020 15:59 | XSLC, LA-2 | 3B/E | Tiantong 1-02 | GTO | Success |
| 72 | Y70 | 6 December 2020 03:58 | XSLC, LA-3 | 3B/E | Gaofen-14 | SSO | Success |
| 73 | Y74 | 19 January 2021 16:25 | XSLC, LA-2 | 3B/E | Tiantong 1-03 | GTO | Success |
| 74 | Y77 | 4 February 2021 15:36 | XSLC, LA-3 | 3B/E | TJS-6 | GTO | Success |
| 75 | Y72 | 2 June 2021 16:17 | XSLC, LA-2 | 3B/E | Fengyun 4B | GTO | Success |
| 76 | Y76 | 5 August 2021 16:30 | XSLC, LA-2 | 3B/E | ChinaSat 2E | GTO | Success |
| 77 | Y78 | 24 August 2021 15:41 | XSLC, LA-3 | 3B/E | TJS-7 | GTO | Success |
| 78 | Y86 | 9 September 2021 11:50 | XSLC, LA-2 | 3B/E | ChinaSat 9B | GTO | Success |
| 79 | Y81 | 27 September 2021 08:20 | XSLC, LA-2 | 3B/E | Shiyan 10 | GTO | Success |
| 80 | Y83 | 24 October 2021 01:27:03 | XSLC, LA-2 | 3B/E | Shijian-21 | GTO | Success |
| 81 | Y79 | 26 November 2021 16:40:04 | XSLC, LA-2 | 3B/E | ChinaSat 1D | GTO | Success |
| 82 | Y82 | 13 December 2021 16:09 | XSLC, LA-3 | 3B/E | Tianlian II-02 | GTO | Success |
| 83 | Y84 | 29 December 2021 16:43 | XSLC, LA-2 | 3B/E | TJS-9 | GTO | Success |
| 84 | Y89 | 15 April 2022 12:00 | XSLC, LA-2 | 3B/E | ChinaSat 6D | GTO | Success |
| 85 | Y85 | 12 July 2022 16:30 | XSLC, LA-2 | 3B/E | Tianlian II-03 | GTO | Success |
| 86 | Y91 | 5 November 2022 11:50 | XSLC, LA-2 | 3B/E | ChinaSat 19 | GTO | Success |
| 87 | Y88 | 29 December 2022 04:43 | XSLC, LA-2 | 3B/E | Shiyan 10-02 | GTO | Success |
| 88 | Y93 | 23 February 2023 11:49 | XSLC, LA-2 | 3B/E | ChinaSat 26 | GTO | Success |
| 89 | Y90 | 17 March 2023 08:33 | XSLC, LA-2 | 3B/E | Gaofen 13-02 | GTO | Success |
| 90 | Y87 | 17 May 2023 02:49 | XSLC, LA-2 | 3B/E | BeiDou-3 G4 | GTO | Success |
| 91 | Y92 | 12 August 2023 17:26 | XSLC, LA-2 | 3B/E | Ludi Tance-4 01A | GTO | Success |
| 92 | Y94 | 9 November 2023 11:23 | XSLC, LA-2 | 3B/E | ChinaSat 6E | GTO | Success |
| 93 | Y75 | 26 December 2023 03:26 | XSLC, LA-2 | 3B/E + YZ-1 | BeiDou-3 M26 BeiDou-3 M28 | MEO | Success |
| 94 | Y95 | 29 February 2024 13:03 | XSLC, LA-2 | 3B/E | Weixing Hulianwang Gaogui-01 | GTO | Success |
| 95 | Y96 | 9 May 2024 01:43 | XSLC, LA-2 | 3B/E | Zhihui Tianwang 1-01A Zhihui Tianwang 1-01B | MEO | Success |
| 96 | Y98 | 30 May 2024 12:12 | XSLC, LA-2 | 3B/E | Paksat-MM1R | GTO | Success |
| 97 | Y97 | 1 August 2024 13:14 | XSLC, LA-2 | 3B/E | Weixing Hulianwang Gaogui-02 | GTO | Success |
| 98 | Y80 | 19 September 2024 01:14 | XSLC, LA-2 | 3B/E + YZ-1 | BeiDou-3 M25 BeiDou-3 M27 | MEO | Success |
| 99 | Y100 | 10 October 2024 13:50 | XSLC, LA-2 | 3B/E | Weixing Hulianwang Gaogui-03 | GTO | Success |
| 100 | Y103 | 3 December 2024 05:56 | XSLC, LA-3 | 3B/E | TJS-13 | GTO | Success |
| 101 | Y99 | 20 December 2024 15:12 | XSLC, LA-2 | 3B/E | TJS-12 | GTO | Success |
| 102 | Y104 | 6 January 2025 20:00 | XSLC, LA-3 | 3B/E | Shijian-25 | GTO | Success |
| 103 | Y106 | 23 January 2025 15:32 | XSLC, LA-2 | 3B/E | TJS-14 | GTO | Success |
| 104 | Y101 | 22 February 2025 12:11 | XSLC, LA-2 | 3B/E | ChinaSat 10R | GTO | Success |
| 105 | Y107 | 9 March 2025 17:17 | XSLC, LA-3 | 3B/E | TJS-15 | GTO | Success |
| 106 | Y? | 26 March 2025 16:30 | XSLC, LA-2 | 3B/E | ChinaSat 9C | GTO | Planned |
| 107 | Y? | April 2025 | XSLC, LA-3 | 3B/E | TJS-16 | GTO | Planned |
| 108 | Y? | April 2025 | XSLC, LA-3 | 3B/E | TJS-17 | GTO | Planned |
| | Y? | May 2025 | XSLC, LA-2 | 3B/E | Tianwen-2 | Heliocentric | Planned |
| | Y? | September 2025 | XSLC, LA-2 | 3B/E | Fengyun 4C | GTO | Planned |
| | Y? | 2027 | XSLC, LA-2 | 3B/E | ChinaSat 27 | GTO | Planned |

## Flight mishaps and anomalies
### 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.
The Xinhua news agency reported that six people were killed and 57 injured. However, the Americans on hand for the launch have testified that "dozens, if not hundreds", of people were seen to gather outside the centre's main gate near the crash site the night before launch. When reporters were being taken away from the site, they found that most buildings had sustained serious damage or had been flattened completely. Other eyewitnesses were noted as having seen dozens of ambulances and many flatbed trucks, loaded with what could have been human remains, being taken to the local hospital.
The cause of the accident was traced to short-circuiting of the vehicle's guidance platform at liftoff.
The participation of Space Systems/Loral in the accident investigation caused great political controversy in the United States. In 1997, the U.S. Defense Technology Security Administration found that China had obtained "significant benefit" from the Review Committee, results of which would improve their "launch vehicles ... ballistic missiles and in particular their guidance systems".
As a result, 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 (Nusantara Dua) of a mass of 5500 kg and was expected to enter service in geostationary orbit at 113.0° East, replacing the Palapa-D satellite. But one of the two YF-75 third stage engines failed to ignite, preventing the Palapa-N1 (Nusantara Dua) satellite from reaching 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.

## Rocket debris

Debris from Long March 3B launches have fallen on nearby villages due to the inland location of China's launch sites. Grid fins for guiding boosters down to Earth more accurately have been tested on Long March 2C and 4B, but not yet on 3B.

## Notable payloads

* Beidou
* Chang'e 3
* Chang'e 4
* Eutelsat W3C
* TJS-5
* Apstar 6C
* Chinasat 9A
* Chinasat 6C
* Palapa-D
* Fengyun 4B
* NigComSat-1
* Tiantong 1-03
* Gaofen 14