YF-77

YF-77
Country of originChina
First flightLong March 5 inaugural flight (2016-11-03)
DesignerAcademy of Aerospace Liquid Propulsion Technology
Applicationsustainer engine
Associated LVLong March 5
StatusIn service
Liquid-fuel engine
PropellantLiquid oxygen / Liquid hydrogen
Mixture ratio5.5 (adjustable)
CycleGas-generator
Configuration
Chamber1
Nozzle ratio49
Performance
Thrust, vacuum700 kN (160,000 lbf)
Thrust, sea-level518 kN (116,000 lbf)
Chamber pressure10.1 MPa (1,460 psi)
Specific impulse, vacuum428.0 seconds (4.197 km/s)
Specific impulse, sea-level316.7 seconds (3.106 km/s)
Burn time525 seconds (8.75 min)
Dimensions
Length2,600 mm (100 in) (with rack)
Diameter1,500 mm (59 in)
Used in
Long March 5 core stage.
References
References[1][2][3]

The YF-77 is China's first cryogenic rocket engine developed for booster applications. It burns liquid hydrogen fuel and liquid oxygen oxidizer using a gas generator cycle. A pair of these engines powers the LM-5 core stage. Each engine can independently gimbal in two planes.[1][4] Although the YF-77 is ignited prior to liftoff, the LM-5's four strap-on boosters provide most of the initial thrust in an arrangement similar to the European Vulcain on the Ariane 5 or the Japanese LE-7 on the H-II.

  1. ^ a b Cite error: The named reference wang-2013 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference nan-2013 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference rp was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference sd-lm5 was invoked but never defined (see the help page).