Chinese rocket engine
YF-20 A YF-20K engine
Country of origin China First flight 1995-06-01 Designer Academy of Aerospace Liquid Propulsion Technology Associated LV Feng Bao 1 , Long March 2 , Long March 3 and Long March 4 Status In Production Propellant N2 O4 / UDMH Cycle Gas Generator Chamber 1 Nozzle ratio 12.69 Thrust, vacuum 816.3 kN (183,500 lbf) Thrust, sea-level 731.5 kN (164,400 lbf) Chamber pressure 7.1 MPa (1,030 psi) Specific impulse , vacuum289 seconds (2.83 km/s) Specific impulse , sea-level259 seconds (2.54 km/s) Burn time 160s Gimbal range ±10° (when integrated on the YF-21B) Diameter 84 centimetres (33 in) Dry mass 712.5 kg (1,571 lb) Feng Bao 1 first stage and Long March 2C , Long March 2D , Long March 2E , Long March 3 , Long March 3A , Long March 3B and Long March 4A , boosters, first stage and second stage.References [ 1] [ 2] [ 3] [ 4]
The YF-20 is a Chinese liquid-fuel rocket engine burning N2 O4 and UDMH in a gas generator cycle. It is a basic engine which when mounted in a four engine module forms the YF-21 . The high altitude variation is known as the YF-22 is normally paired with the YF-23 vernier to form the YF-24 propulsion module for second stages. New versions when used individually for booster applications are called YF-25 .[ 5] [ 6]
Versions
The basic engine has been used since the Feng Bao 1 rocket and has been the main propulsion of the Long March 2 , Long March 3 and Long March 4 families.[ 6] [ 7] [ 8]
YF-20 : Core engine. Flown originally on the Feng Bao 1 and Long March 2A .[ 8] [ 9] [ 10]
YF-20A : Core engine.[ 11]
YF-20B (a.k.a. DaFY5-1 ): Core engine, also used on the boosters.[ 2] [ 12] [ 13]
YF-20C : Core engine, also used on the boosters.
YF-20D : Core engine, also used on the boosters.
YF-20E : Core engine, also used on the boosters.
YF-22 : Upper stage version with enlarged nozzle are ratio. Flown originally on the Feng Bao 1 second stage with no verniers, and on the Long March 2A with the YF-23 verniers as the YF-24 .[ 8] [ 10]
YF-22A : Upper stage version.
YF-22B (a.k.a. DaFY20-1 ): Upper stage version.[ 12] [ 13]
YF-22C : Upper stage version.
YF-22D : Upper stage version.
YF-22E : Upper stage version.
YF-25 : Booster stage version.
Modules
A YF-24B engine
While the basic engine was used multiple times, it was only used as a single engine for booster application. It is usually bundled into modules of multiple engines.[ 10] [ 14] [ 15]
The relevant modules for first stage application are:
YF-21 : A module comprising four YF-20. Flown originally on the Feng Bao 1 and Long March 2A .[ 8] [ 10]
YF-21A : A module comprising four YF-20A. Improved version.
YF-21B (a.k.a. DaFY6-2 ): A module comprising four YF-20B. Improved version which increased thrust by 7%.[ 12]
YF-21C : A module comprising four YF-20C. Improved version.[ 16]
YF-21D : A module comprising four YF-20D. Improved version.
YF-21E : A module comprising four YF-20E. Improved version.
The relevant modules for second stage application are:
YF-24 : A module comprising an YF-22 and a YF-23 vernier. First flown on the Long March 2A .[ 10]
YF-24A : A module comprising an YF-22A and a YF-23A verniers.
YF-24B : A module comprising an YF-22B and a YF-23B verniers.
YF-24C : A module comprising an YF-22C and a YF-23C verniers.
YF-24D : A module comprising an YF-22D and a YF-23D verniers.
YF-24E : A module comprising an YF-22E and a YF-23E verniers.[ 16]
References
Liquid fuel
Cryogenic
Hydrolox (LH2 / LOX )
China
Europe
India
Japan
Russia
United States
Methalox (CH4 / LOX )
China
United States
Russia
Europe
Semi- cryogenic
Kerolox (RP-1 / LOX )
China
India
Russia
NK-15
NK-33, 44
RD-58
RD-0105, 0109
RD-0107, 0108, 0110
RD-0110R
RD-0124
RD-107, 108, 117, 118
RD-120
RD-170, 171
RD-180
RD-191, 151, 181
RD-193
S1.5400
Spain
Ukraine
United States
Storable
Hypergolic (Aerozine , UH 25 , MMH , or UDMH / N2 O4 , MON , or HNO3 )
China
Europe
India
Israel
North Korea
Russia
17D61
RD-0202 to 0206, 0208 to 0213
RD-0207, 0214
RD-0216, 0217, 0235
RD-0233, 0234
RD-0236
RD-0237
RD-0243 to 0245
RD-0255 to 0257
RD-215 to 219
RD-250 to 252, 261, 262
RD-253, 275
RD-263, 268, 273
RD-270
S5.92
S5.98M
Ukraine
United States
Other
Solid fuel
China
Europe
India
Iran
Israel
Japan
United States
* Different versions of the engine use different propellant combinations
Engines in italics are under development