Yuanzheng-1
| Manufacturer | CALT |
|---|---|
| Country of origin | China |
| Used on | Long March 3B and Long March 3C fourth stage[1] |
| Associated stages | |
| Comparable | Fregat |
| Launch history | |
| Status | Active |
| Total launches | 4 |
| Successes (stage only) | 4 |
| Failed | 0 |
| Lower stage failed | 0 |
| First flight |
2015-03-30 BDS I1-S Mission |
| Engine details | |
| Engines | 1 YF-50D[1][2] |
| Thrust | 6.5 kN (1,500 lbf)[1] |
| Specific impulse | 315.5 seconds[1] |
| Fuel | UDMH/N2O4[1] |
The Yuanzheng-1 (YZ-1) (Chinese: 远征一号; pinyin: Yuǎn Zhēng Yī Hào; literally: "Expedition One") is a restartable rocket upper stage developed by the China Academy of Launch Vehicle Technology (CALT) used as a fourth stage to enable the Long March 3B and Long March 3C launch vehicles to deploy payloads directly to high energy orbits like medium Earth orbit (MEO) and geostationary orbit (GSO). Since the Long March third stage cannot restart, it cannot circularize a GSO orbit from a geostationary transfer orbit. The YZ-1 was designed for restart capability, and to remain operational for more than 6 hours required to reach the transfer orbit apogee for the circularization burn. The YZ-1 enabled the deployment of satellite pairs for the BeiDou Navigation Satellite System and communications satellites directly to their orbits. This eliminates the need for the spacecraft to include a Liquid Apogee Engine or apogee kick motor.[3]
The YZ-1 has a thrust of 6.5 kN (1,500 lbf) with a specific impulse of 315.5 seconds. It uses the storable hypergolic propellants unsymmetrical dimethylhydrazine (UDMH) and dinitrogen tetroxide (N2O4), and can perform at least two burns within its rated life of 6.5 hours.[4]
History
Little is known at the time regarding this stage. Besides the basic characteristics, it is known that there will be a second version specifically designed for the Long March 5 called Yuanzheng-2. It was presented in a 2013 paper.[3] And had its first flight on May 30th, 2015. The debut flight of the Long March 7 included an improved version of the small diameter version called Yuanzheng-1A.[5]
| Date (UTC) | Carrier Rocket | Stage Model | Launch site | Mission | Result |
|---|---|---|---|---|---|
| 2015-03-30 13:52 | Long March 3C | YZ-1 | Xichang | BDS I1-S | Success |
| 2015-07-25 12:29 | Long March 3B | YZ-1 | Xichang | BDS M1-S / BDS M2-S | Success |
| 2016-02-01 07:29 | Long March 3C | YZ-1 | Xichang | BDS M3-S | Success |
| 2016-06-25 12:00 | Long March 7 | YZ-1A | Wenchang | Inaugural Mission | Success |
Versions
Currently, there is known to be three versions:
- Yuanzheng-1 (AKA YZ-1) (Chinese: 远征一号; pinyin: Yuǎn Zhēng Yī Hào; literally: "Expedition One"): Initial version used with the Long March 3. It could perform missions of 6.5 hours, make two ignitions, perform one spacecraft deployment operation.[6][7]
- Yuanzheng-1A (AKA YZ-1A) (Chinese: 远征一号甲; pinyin: Yuǎn Zhēng Yī Hào Jiǎ; literally: "Expedition One A"): Improved version used with the Long March 7. Improved version with mission life extended to 48hs, capability to perform at least 9 ignitions and ability to do 7 different separation events. It also includes improved thermal control system, guidance algorithms and orbit planning for multiple payload deployment missions. It will be used as the base system for future deep space propulsion stages, space tugs and orbital servicing and debris removal spacecraft.[6][8]
- Yuanzheng-2 (AKA YZ-2) (Chinese: 远征二号; pinyin: Yuǎn Zhēng Èr Hào; literally: "Expedition Two"): New version used with the 5.2 m (17 ft) Long March 5 upper stage.[9]
References
- 1 2 3 4 5 6 Norbert Bgügge. "Photo Gallery CZ-3CE". B14643.DE. Retrieved 2015-07-25.
- ↑ "New Launch". www.casc11.com (in Chinese). Xi'an Aerospace Propulsion Institute. 2015-07-26. Retrieved 2015-08-02.
- 1 2 Kun, Ma; Wu, Guo; Song, Guan; Zhibin, Ma; Tongyu, Li (2013). "上面级发展现状及趋势分析" [Development Status and Trend Analysis of Upper Stages]. MISSILES AND SPACE VEHICLES (in Chinese). No.6 2013 (329): 24–28. doi:10.7654/j.issn.1004-7182.20130606.
- ↑ Norbert Bgügge. "YZ-1 space tug". B14643.DE. Retrieved 2015-07-25.
- ↑ "长征七号首飞成功 空间实验室任务大幕拉开" [Successful maiden flight of the Long March 7 mission Damulakai]. www.spacechina.com (in Chinese). 2016-06-25. Retrieved 2016-06-25.
- 1 2 "升级版的中国“太空摆渡车”将带来什么?" [What will enable the upgraded space bus?]. www.chinanews.com (in Chinese). 2016-06-25. Retrieved 2016-06-27.
- ↑ "远征一号上面级" [Yuanzheng-1 Upper Stage]. www.chinaspaceflight.com (in Chinese). 2016-06-07. Retrieved 2016-06-30.
- ↑ "远征一号甲上面级(YZ-1A)" [Yuanzheng-1A Upper Stage (YZ-1)]. www.chinaspaceflight.com (in Chinese). 2016-06-26. Retrieved 2016-06-30.
- ↑ "远征二号上面级：今年发射的“长征五号”火箭将启用新研制上面级“远征二号”" [Yuanzheng-2 upper stage: this year's launch of the Long March 5 rocket upper stage will enable the development of new "Yuanzheng-2"]. www.chinaspaceflight.com (in Chinese). 2016-03-30. Retrieved 2016-06-30.