Article · Wikipedia archive · Last revised Jul 26, 2026

YF-40

The YF-40 is a Chinese liquid rocket engine burning N2O4 and UDMH in a gas generator cycle. It has dual gimbaling combustion chambers.

Last revised
Jul 26, 2026
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≈ 1 min
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YF-40B
Country of originChina
First flight1995-06-01
DesignerAcademy of Aerospace Liquid Propulsion Technology
Associated LVLong March 1D, Long March 4
StatusIn Production
Liquid-fuel engine
PropellantN2O4 / UDMH
Mixture ratio2.14
CycleGas Generator
Configuration
Chamber2
Nozzle ratio55
Performance
Thrust, vacuum103 kN (23,000 lbf)
Chamber pressure4.6 MPa (670 psi)
Specific impulse, vacuum303 seconds (2.97 km/s)
Burn time412s
Gimbal range±4.5°
Dimensions
Length120 centimetres (47 in)
Diameter63 centimetres (25 in)
Dry mass83 kg (183 lb)
Used in
Long March 1D second stage and Long March 4 third stage.
References
References123456

The YF-40 is a Chinese liquid rocket engine burning N2O4 and UDMH in a gas generator cycle. It has dual gimbaling combustion chambers.

Originally it was developed for the Long March 1D second stage.6 It is used on the third stage of the Long March 4 family of launch vehicles.137

References

References

  1. "Long March". Rocket and Space Technology. Retrieved 2015-07-08.
  2. "YF-40". Encyclopedia Astronautica. Archived from the original on 2015-08-24. Retrieved 2015-07-15.
  3. Gunter Dirk Krebs. "CZ-4 (Chang Zheng-4)". Gunter's Space Page. Retrieved 2015-07-15.
  4. Sutton, George Paul (November 2005). "Liquid Rocket Propellant Engines in the People's Republic of China". History of Liquid Propellant Rocket Engines. AIAA. p. 873. ISBN 978-1563476495. Retrieved 2015-07-15.
  5. Mowthorpe, Matthew (2004). "Chinas Military Space Program". The Militarization and Weaponization of Space. Lexington Books. p. 90. ISBN 978-0739107133. Retrieved 2015-07-15.
  6. "Chang Zheng-1 (Long March-1)". SinoDefence. Archived from the original on 2015-07-16. Retrieved 2015-07-15.
  7. Harvey, Brian (2004). "Launch Centers Rockets and Engines". China's Space Program — From Conception to Manned Spaceflight. Springer Science & Business Media. p. 231. ISBN 978-1852335663. Retrieved 2015-07-15.