The YF-115 is a Chinese liquid rocket engine burning LOX and kerosene in an oxidizer-rich staged combustion cycle.[4] A high efficiency/high thrust environmental-friendly rocket engine was always an objective within Programme 863. Development began in the 2000s, along with its sibling, the bigger YF-100, which would power the LM-5, LM-6 and LM-7 boosters and first stages.[5][6][7] Testing was directed by the China National Space Administration (CNSA) commencing in 2005. Development works are mainly carried out by the Xi'an Aerospace Propulsion Institute. It will be used as upper stage engine for China's next generation of medium and light environmental-friendly launch vehicles, namely the Long March 6 and the Long March 7.[5][6][7] During early 2012, the engine system successfully passed vacuum testing.[8] It is China's first upper stage rocket engine to adopt the staged-combustion cycle.

Country of originChina
First flightLong March 6 inaugural flight (2015-09-20)
DesignerAcademy of Aerospace Liquid Propulsion Technology[1]
Associated LVLong March 6 and Long March 7[2][3]
StatusIn service
Liquid-fuel engine
PropellantLOX[4] / RP-1[4]
Mixture ratio2.5[4]
CycleOxidizer-rich Staged combustion[4]
Thrust, vacuum176.5 kN (39,700 lbf)[citation needed]
Thrust, sea-level147.1 kN (33,100 lbf)[citation needed]
Chamber pressure12 MPa (1,700 psi)[4]
Specific impulse, vacuum341.5 seconds (3.349 km/s)[4]
Length2,325 millimetres (91.5 in)[4]
Diameter946 millimetres (37.2 in)[4]
Used in
Long March 6 second stage and Long March 7 second stage.[2][3]

In the LM-6 upper stage it will use a single YF-115 with gimbaled mount. While the LM-7 upper stage will use four such engines. But in this latter case, two engines will be fixed and two will be gimbaled.[citation needed]

See alsoEdit

  • LM-6 – Rocket family that uses the YF-115.
  • LM-7 – Rocket family that uses the YF-115.
  • YF-100 – First stage Chinese rocket engine which is the technological base of the YF-115.


  1. ^ "采用了什么新技术吗?20颗微小卫星送入预定轨道!_参考消息_太行军事网". www.thjunshi.com (in Chinese). Retrieved 2016-04-11.
  2. ^ a b Gunter Dirk Krebs. "CZ-6 (Chang Zheng-5)". Gunter's Space Page. Retrieved 2015-07-02.
  3. ^ a b Gunter Dirk Krebs. "CZ-7 (Chang Zheng-5)". Gunter's Space Page. Retrieved 2015-07-02.
  4. ^ a b c d e f g h i j "中国新一代液氧煤油发动机3:YF100/115主要特性 - 深空网". www.shenkong.net (in Chinese). Archived from the original on 2016-03-04. Retrieved 2016-04-11.
  5. ^ a b "Chang Zheng-5 (Long March-5)". SinoDefence. Archived from the original on 2015-07-03. Retrieved 2015-07-02.
  6. ^ a b "Chang Zheng-6 (Long March-6)". SinoDefence. Retrieved 2015-07-02.
  7. ^ a b "Chang Zheng-7 (Long March-7)". SinoDefence. Retrieved 2015-07-02.
  8. ^ "长征七号火箭发动机抽真空系统顺利通过试验 (Long March 7 rocket engine system passes vacuum test)" (in Chinese). CASC. Retrieved 2015-07-02.