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.

The YF-100 and YF-77 engines used by Long March 5. The chief designer of CZ-5 is Li Dong ( Chinese : 李东 ) of the China Academy of Launch Vehicle Technology (CALT). The CZ-5 family includes three primary modular core stages of 5.2-m diameter (maximum).

YF-77 火箭发动机是 中国航天推进技术研究院 （中国航天科技集团公司第六研究院）为 长征五号 芯一级研制的燃气发生器循环大推力氢氧发动机。 采用双涡轮分别驱动液氢泵和液氧泵工作方式，具有混合比和推力调节功能，以提高火箭运载能力。 真空比冲大于428 s，地面一次起动。 YF-77火箭发动机与 YF-100 液氧煤油火箭发动机一同成为我国新一代运载火箭的主要动力，并有可能被用于中国未来的重型运载火箭上面级。 实际飞行状态的YF-77由2台独立工作的单机并联构 …

YF-77 是 中华人民共和国 研发的一款 液体火箭发动机，用於 长征五号系列火箭 芯一级，发动机燃料为 液氧 和 液氢，采用 燃气发生器循环。 2001年12月批准立项，由 北京航天动力研究所 研制 [4]，2016年11月3日投入使用，在 长征五号 上成功进行首次飞行。 相较于过去发展的 YF-73 和 YF-75，YF-77是中国研制的第一种大推力氢氧发动机。 1995年，中国开展新一代运载火箭方案论证以及液氧煤油与氢氧两种大推力火箭发动机关键技术研究 [5]。

Jan 14, 2021 · The new staged combustion cycle engine is an upgrade to CASC’s YF-77 liquid hydrogen-liquid oxygen gas-generator oxygen engine, providing greater thrust and efficiency. Progress includes...

yf-77火箭发动机是中国航天推进技术研究院（中国航天科技集团公司第六研究院）为新一代大运载火箭长征五号芯一级研制的燃气发生器循环大推力氢氧发动机。采用双涡轮分别驱动液氢泵和液氧泵工作方式，具有混合比和推力调节功能，以提高火箭运载能力。

Nov 3, 2016 · The YF-77 is China’s first booster-class rocket engine to burn super-cold liquid hydrogen and liquid oxygen as propellants, and the largest such fully cryogenic powerplant ever made...

CAALPT LOx/LH2 rocket engine for next generation Chinese launch vehicle series. It was an indigenous development based on Chinese experience with the YF-73 and YF-75 upper stage engines. AKA: YF-50. Status: Operational 2016. Date: 2016. Thrust: 700.00 kN (157,360 lbf). Unfuelled mass: 2,700 kg (5,900 lb). Specific impulse: 430 s.

The YF-77 engine is the first booster rocket engine in China with cryogenic Oxygen/Hydrogen. The YF-77 engine utilizes a gas generator cycle and each engine has a thrust rating of 700-kN in vacuum at an oxidizer-to-fuel mixture ration (O/F) of 5.5.

The YF-77 engine, designed by the Academy of Aerospace Propulsion Technology (AALPT), China, is a high performance and reliability LH2/LO2 booster designed for the next-flagship Chinese launch vehicle, called Long-March 5. Two YF-77 engines fly on the core stage of the Long-March 5 launch vehicle.