All is inherent in the rocket and space technology. However, particular attention is claimed by the upper stage of the launch vehicle, because it is this unit that places the payload into the final orbit and its extremely high precision effects the success of the launch and proper functioning of the payload.

Upper stage production is the technology possessed by few enterprises all over the world. To date we have every reason to state that Yuzhnoye SDO jointly with PA Yuzhmash and other Ukrainian joint productions possess technologies and sufficient testing capabilities to provide the full cycle of stage production.

As a recap, in August 2019, Stage 3 (upper stage) of the medium capacity Cyclone-4 launcher, powered by the liquid-propellant engine RD861K, successfully underwent test firing at the PA Yuzhmash test bench. In June 2020, second phase of the engine final development tests was successfully completed. Flight tests integrated with launch vehicle are ahead.

It is necessary to note that the upper stage of the light capacity Cyclone-4 is versatile. Considering the designed-in potential of the Stage, we believe that in future it can be installed not only on the Cyclone family launchers, but can also be used as the upper stage on the other launchers.

Cyclone-4 rocket Stage 3 features are:

– high payload capability due to high volume (around 11 tons) of propellants and high specific impulse (330 s in vacuum) of the main engine with up to 5 burns in flight;

– liquid jet system provides high maneuvering performance;

– high precision of SC injection provided by the new control system based on the integrated inertial navigation system: laser SINS and satellite navigation system;

– high quantity and quality of the measured parameters provided by the new system of telemetering measurements;

– high operation safety provided by the highest possible autonomy of the pre-launch processing, launch readiness monitoring and launch control procedures;

– minimal environmentally harmful effect provided by the prevention of propellants discharge during pre-launch processing.

To install the Stage 3 (upper stage) of the Cyclone-4 launcher on the other advanced modified launchers, such as Cyclone-4M launch vehicle, Yuzhnoye SDO now works to unify the Stage, binding type separation device to separate the satellites and fairing and is getting ready to unfold the activities in the following areas:

• modification of PHS in order to provide the autonomous filling of Stage 3 with propellants at the fueling and neutralization station;
• modification of the fuel system to provide its ampulization for safe operation of the fueled Stage 3 (including when integrated with LV) at the launch site;
• introduction of the new scheme of stage separation using pneumopusher instead of the braking solid-propellant rocket motor, which separates at the previous stage;
• unification of the Stage 3 interface with space head unit and interstage bay;
• modification of the body, systems, units and assemblies (including pyromechanisms) to provide the import substitution and diversification of the parts and components, previously supplied by enterprises from the Russian Federation.