Liquid-Propellant Rocket Engine 11D33

The first domestic liquid-propellant rocket engine with afterburning of generated gas in a combustion chamber allowed to achieve a specific impulse of up to 340 kgf s/kg in vacuum when using main components.
For this liquid-propellant rocket engine the following equipment has been newly designed: the engine pneudraulic system ensuring its reliable start in space environment after staying in vacuum for a long period; gas generator of minimum mass and dimensions serving to convert liquid oxygen into gaseous oxygen at a temperature 350-450°C within a uniform field of temperatures; a reliably cooled combustion chamber with a high gas extension coefficient in a nozzle.
The turbopump initial spin-up is pyrotechic. The engine is attached to a Cardan's suspension with an angle of rotation of up to 3°. The roll control is executed via rotary steering nozzles using reduction gas.
The combustion chamber is made of titanium alloy.
Thus far, the engine is still being used in upper stage L of LV Molniya.

Liquid-Propellant-Rocket Engine 11D58M

A vacuum restarting engine designed for a durable use in space environment.
The engine is derived from engine 11D33 through improving its performance.
The engine has a more heat-intensive combustion chamber, therefore, RG-1 is used as fuel. When launching heavy-lift spacecraft, synthine can be used in the capacity of fuel without re-designing the engine.
For restarting, the engine contains a multi-ignition unit which tanks are filled with starting fuel. Using booster pumps at outlets of fuel and oxidizer tanks allowed to make fuel tanks lighter and a system regulating an oxidizer-fuel ratio including a temperature control allows to maintain a constant mass ratio of components instead of a volume ratio as in other engines.
Until now, engine 11D58M is being successfully operated.