Encyclopedia Astronautica

Credit: Yuzhnoye
Yuzhnoye N2O4/UDMH rocket engine. 5.2 kN. RT-23 MIRV-bus. Out of Production. Isp=305s. Engine consisted of two turbopumps with gas generators and two feeders; a single chamber main engine; and 16 liquid thrusters for attitude control and translation.

The RD-866 engine powered the MIRV distribution bus. The engine provided:

  • delivery of fuel delivery to the steering units used for missile flight control at the end of the first stage burn and during the second and third stage engine burns
  • roll control during third stage burn
  • during dispensing of multiple independently targeted warheads, provision of attitude and translation forces in multiple burns of the main engine and peripheral thrusters
  • fuel delivery to the hydraulic actuators that gimbaled the main engine during warhead distribution
The multifunction engine operated under a generator scheme. Propellants were fed under a combined scheme (pressure-fed and pump delivery). A broad range of flow-rates and pressures were provided according to the engine mode. The engine consisted of a centralized propellant supply source composed of two turbopumps with gas generators and two feeders; a single chamber main engine; and 16 liquid thrusters for attitude control and translation. Overall vacuum thrust of between minus 926 KN to plus 5036 kN could be provided at a mean specific impulse of 305.5 seconds for the design dispensing profile. The thrusters could be fired in continuous or 10 Hz pulsed modes.

Summary: One main and 16 control thrusters. 5.20 kN + 16 x 116 N. Chamber pressure 40.7 / 5.56 bar. Specific impulse 305.5 / 245 sec. Burn time 330 / 1200 sec. Oxidizer to fuel ratio 2.03 / 1.85.

Application: RT-23 / RS-22 (SS-24) MIRV-bus.


Chambers: 1 + 16. Engine: 125 kg (276 lb). Chamber Pressure: 40.70 bar. Thrust to Weight Ratio: 4.22. Oxidizer to Fuel Ratio: 2.03.

AKA: 3D65.
Status: Out of Production.
Unfuelled mass: 125 kg (276 lb).
Height: 1.19 m (3.89 ft).
Diameter: 1.98 m (6.49 ft).
Thrust: 5.20 kN (1,169 lbf).
Specific impulse: 306 s.
Burn time: 330 s.
First Launch: 1980-83.

More... - Chronology...

Associated Countries
See also
Associated Launch Vehicles
  • RT-23 Ukrainian intercontinental ballistic missile. The only rail-based ICBM ever deployed. Developed by Yuzhnoye in the Ukraine was protracted, but understandable given the huge technical challenges. Twelve years of design and testing was followed by deployment from 1988. All were retired by 2003. More...

Associated Manufacturers and Agencies
  • Yuzhnoye Ukrainian manufacturer of rockets, spacecraft, and rocket engines. Yangel Design Bureau, Dnepropetrovsk, Ukraine. More...

Associated Propellants
  • N2O4/UDMH Nitrogen tetroxide became the storable liquid propellant of choice from the late 1950's. Unsymmetrical Dimethylhydrazine ((CH3)2NNH2) became the storable liquid fuel of choice by the mid-1950's. Development of UDMH in the Soviet Union began in 1949. It is used in virtually all storable liquid rocket engines except for some orbital manoeuvring engines in the United States, where MMH has been preferred due to a slightly higher density and performance. More...

  • Zhelyez x-plane book,
  • Lardier, C, "SS-18", Air et Cosmos, 2 Sept. 1994 via Dietrich Haeseler.
  • Siddiqi, Asif A, Soviet Space Web Page, 1999 via Dietrich Haeseler. Web Address when accessed: here.
  • Shnyakin, V N, Shidkostnye Raketye Dvigateli - Opisanie i Osnovnye Tekhnicheskie Dannye, GKB Yuzhnoe "Yangel", Dnepropetrovsk 1996 via Dietrich Haeseler.

Associated Stages
  • RT-23-3 N2O4/UDMH propellant rocket stage. Loaded mass 15,000 kg. Thrust 206.00 kN. More...

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