The RD-0243 (Russian: Ракетный Двигатель-0243, romanized: Raketnyy Dvigatel-0243, lit. 'Rocket Engine 0243') is a propulsion module composed of an RD-0244 main engine and a RD-0245vernier thruster. Both are liquid-fuel rocket engines, burning a hypergolic mixture of unsymmetrical dimethylhydrazine (UDMH) fuel with dinitrogen tetroxide (N2O4) oxidizer. The RD-0244 main engine operates in the oxidizer rich staged combustion cycle, while the vernierRD-0245 uses the simpler gas generator cycle. Since volume is at a premium on submarine launches, this module is submerged on the propellant tank.[3] Its development period was from 1977 to 1985, having had its first launch on December 27, 1981. Originally developed for the RSM-54, it was used later for the Shtil'.[1]
