The RD-119 (GRAU Index 8D710) was a liquid rocket engine, burning liquid oxygen and UDMH in the gas-generator cycle.[3] It has a huge expansion ratio on the nozzle and uses a unique propellant combination to achieve an extremely high isp of 352 s for a semi-cryogenic gas-generator engine. It also has a unique steering mechanism. The engine main nozzle is fixed, and the output of the gas generator is fed into four nozzles on the side of the engine. Instead of using gimbaled verniers to supply vector control, the combustion gases are distributed by an electrically driven system that can control the thrust among the nozzles.

RD-119 (РД-119)
RD-119 rocket engine.jpg
Museum of Space and Missile Technology (Saint Petersburg). RD-119 rocket engine for Cosmos LV(11К63) second stage.
Country of originUSSR
DesignerEnergomash, V. Glushko[1]
Associated LVKosmos-2[1]
StatusOut of production
Liquid-fuel engine
PropellantLOX[2] / UDMH[2]
Mixture ratio1.5[2]
CycleGas generator[2][3]
Nozzle ratio102
Thrust, vacuum106 kilonewtons (24,000 lbf)[1]
Thrust, sea-level65.6 kilonewtons (14,700 lbf)[2]
Chamber pressure7.9 megapascals (1,150 psi)[1]
Specific impulse, vacuum352 s (3.45 km/s)[1]
Specific impulse, sea-level220 s (2.2 km/s)[2]
Burn time260 s[2]
Gimbal rangeFixed with four fixed steering nozzles
Length2,170 millimetres (85 in)[1]
Diameter1,024 millimetres (40.3 in)[1]
Dry weight168.5 kilograms (371 lb)[1]
Used in
Kosmos-2 (11K63)[1]


Between 1958 and 1960, Glushko's OKB 456 developed the RD-109 for the Block-I of the 8K73 project — a liquid-oxygen/UDMH version of the R-7. But Korolev refusal to use such a toxic combination shelved the project.[4] When Yangel's OKB-586 was tasked with developing a launch vehicle out of the R-12, they had to develop an upper stage from scratch. The critical issue was the low specific impulse of the first stage, and thus a very high-efficiency upper-stage engine was needed. For this Glushko offered to adapt the RD-109, and Yangel accepted the proposal.[3] It flew some very important missions on the Kosmos-2 launch vehicle, with about 165 engines produced.[2][5]


This engine had two versions.

  • RD-109: GRAU Index 8D711, also known as GDU-10. It was the original proposal for the 8K73 Project Blok-I stage.
  • RD-119: GRAU Index 8D710. It was the version used on the Kosmos-2.
RD-119 family of engines
Engine RD-109 RD-119
AKA 8D711 or GDU-10 8D710
Development 1957–1960[4] 1960–1963 [2]
Engine type Gas generator[2][3]
Propellant LOX/UDMH[2]
Combustion-chamber pressure 7.75 MPa (1,124 psi)[1] 7.9 MPa (1,150 psi)[1]
Thrust (vacuum) 101.6 kN (22,800 lbf)[1] 106 kN (24,000 lbf)[1]
Thrust (sea level) N/A 65.6 kN (14,700 lbf)[2]
Isp (vacuum) 334 s (3.28 km/s)[1] 352 s (3.45 km/s)[1]
Isp (sea level) N/A 220 s (2.2 km/s)[2]
Burn time 330 s[4] 260 s[2]
Length 2,280 mm (90 in)[1] 2,170 mm (85 in)[1]
Diameter 1,024 mm (40.3 in)[1] 1,024 mm (40.3 in)[1]
Dry mass 210 kg (460 lb)[1] 168.5 kg (371 lb)[1]
Use 8K73 project Kosmos-2

See alsoEdit


  1. ^ a b c d e f g h i j k l m n o p q r s t u v "NPO Energomash list of engines". NPO Energomash. Archived from the original on 7 November 2014.
  2. ^ a b c d e f g h i j k l m n o "RD-119". Encyclopedia Astronautica. Archived from the original on 2017-11-11. Retrieved 2015-06-26.
  3. ^ a b c d Zak, Anatoly. "Kosmos-2". RussianSpaceWeb.com. Retrieved 2015-06-26.
  4. ^ a b c "RD-109". Encyclopedia Astronautica. Archived from the original on 2017-11-11. Retrieved 2015-06-26.
  5. ^ "Kosmos-2". Encyclopedia Astronautica. Archived from the original on 2017-11-11. Retrieved 2015-06-26.


Gluschko, V. P. (1985). Kosmonavtika Entsiklopediya - Cosmonautic Encyclopedia (Russian) - Космонавтика Энциклопедия (PDF). Moscow. p. 329. Archived (PDF) from the original on 11 July 2022.

External linksEdit

  • NPO Energomash official site.
  • RussianSpaceWeb information on the engine