RD-253

RD-253
Mock-up of a RD-275 rocket motor at the Paris Air Show in 2013
Country of origin Soviet Union
 Russia
First flightRD-253: 1965
RD-275: 1995
RD-275М: 2007
DesignerNPO Energomash, Valentin Glushko
ManufacturerProton-PM
ApplicationFirst stage booster
Associated LVProton
SuccessorRD-254, RD-256, RD-275, RD-275М
StatusOperational
Liquid-fuel engine
PropellantN2O4 / UDMH
Mixture ratio2.67
CycleStaged combustion
Configuration
Chamber1
Nozzle ratio26.2
Performance
Thrust, vacuumRD-253: 1,630 kN (370,000 lbf)
RD-275: 1,750 kN (390,000 lbf)
RD-275М: 1,832 kN (412,000 lbf)
Thrust, sea-levelRD-253: 1,470 kN (330,000 lbf)
RD-275: 1,590 kN (360,000 lbf)
RD-275М: 1,671 kN (376,000 lbf)
Thrust-to-weight ratio156.2
Chamber pressureRD-253: 14.7 MPa (2,130 psi; 147 bar)
RD-275: 15.7 MPa (2,280 psi; 157 bar)
RD-275M: 16.5 MPa (2,390 psi; 165 bar)
Specific impulse, vacuumRD-253: 316s
RD-275: 316s
RD-275M: 315.8s
Specific impulse, sea-levelRD-253: 285s
RD-275: 287s
RD-275M: 288s
Gimbal range7.5°, single plane
Dimensions
Length3 m (9.8 ft)
Diameter1.5 m (4 ft 11 in)
Dry massRD-253: 1,080 kg (2,380 lb)
RD-275: 1,070 kg (2,360 lb)
RD-275M: 1,070 kg (2,360 lb)
References
References[1][2][3][4][5][6][7]

The RD-253 (Russian: Ракетный Двигатель-253 (РД-253), romanizedRaketnyy Dvigatel-253, lit.'Rocket Engine-253') and its later variants, the RD-275 and RD-275M, are liquid-propellant rocket engines developed in the Soviet Union by Energomash. The engines are used on the first stage of the Proton launch vehicle and use an oxidizer-rich staged combustion cycle to power the turbopumps. The engine burns UDMH/N2O4, which are highly toxic but hypergolic and storable at room temperature, simplifying the engine's design.

  1. ^ Cite error: The named reference npoem-rd253 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference ea-rd211d48 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference ea-rd253 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference protonpm-rd276 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference ea-protonk was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference rsw-protonhist was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference rsw-rd353 was invoked but never defined (see the help page).