The RD853 engine generates thrust and controls flight of launch vehicle second stages. The engine comprises a chamber, turbopump assembly with a gas generator, additional gas generator, pyrostarter, four steering nozzles, and control units.

The open-cycle RD853 is a single-chamber, dual-mode, single-burn engine with a turbo-pump-feed system using hypergolic propellants.

The stage flight is controlled in all stabilization axes. At ignition, the pyrostarter spins the turbopump assembly rotor.

The turbopump assembly turbine uses producer gas as a working fluid.

The engine development started in 1960 and discontinued in 1963 in design development test phase.

Basic Specifications

Engine mass, kg

485

Propellants:

Oxidizer                                                                         

Fuel

 

Nitric acid +27% N2O4

Unsymmetrical dimethylhydrazine

Vacuum thrust, kgf

47680

Vacuum specific impulse, kgf·s/kg

300,7

Steering nozzle angle, ang.deg

±65

Propellant mixture ratio

2,41

Running time in flight, s

Up to 164