A Russian Rockot launch vehicle has lifted-off from the Plesetsk space center in northern Russia, carrying the Gonets-M (No. 2) satellite, and two Kosmos satellites. Launch took place at 03:30 UTC (07:30 Moscow time) on Wednesday.
The Russian launch system is tailored to payloads requiring a performance of at least 1,950 kg for launches into Low Earth Orbit (LEO). The three-stage liquid fuelled rocket has dedicated launch facilities at Plesetsk Cosmodrome under the control of Eurockot.
Rockot is a fully operational, three stage, liquid propellant Russian launch vehicle which is being offered commercially by Eurockot Launch Services for launches into low earth orbit. The German-Russian joint venture company was formed specifically to offer this vehicle commercially.
However, Wednesday’s launch is being classed as a military mission.
The Rockot launch vehicle uses the the SS-19/(RS-18) Stiletto ICBM for its first two stages. The SS-19, which was originally developed as the Russian UR-100N ICBM series, was designed between 1964 and 1975. Over 360 SS-19 ICBMs were manufactured during the 70s and 80s.
The Breeze-KM third stage uses a re-startable storable liquid propellant engine that has been used in many other Soviet space projects.
The booster unit – which provides the first and second stages of Rockot – is taken from existing SS-19 missiles and is accommodated within an existing transportation/launch container. The third stage – which provides the orbital capability of the launcher – is newly manufactured.
This upper stage contains a modern, autonomous control/guidance system which controls all three stages. The upper stage multiple engine ignition capability allows implementation of various payload injection profiles.
The Rockot second stage has an external diameter of 2.5 metres and a length of 3.9 metres. It contains a closed-cycle, turbopump-fed, fixed main engine designated RD-0235 and verniers designated RD-0236 for directional control – as listed in the 200 page vehicle overview presentation (L2).
Separation of the first and second stages is a “hot separation” – due to the fact that the vernier engines are ignited just before the separation. The exhaust gases are diverted by special hatches within the first stage.
After separation, the first stage is braked by retro rockets, then the second stage main engine is ignited. Like the first stage it contains a common bulkhead and a hot gas pressurisation system.
The Breeze-KM stage – which has now been adopted as the standard version of the third stage for the commercial version of Rockot – is a close derivative of the original Breeze-K stage flown during the first three Rockot flights.
It comprises three main compartments which include the propulsion compartment, the hermetically sealed equipment compartment and the interstage compartment. To allow larger satellites to be accommodated and to reduce dynamic loads, structural changes to the Breeze-K stage were introduced.
The structure of the equipment bay of the original Breeze-K stage has been widened and flattened by redistribution of the control equipment.
With two Kosmos satellites also riding as passengers, the Gonets-M satellite – according to the Russian Space Agency – is intended to provide digital user terminal GLONASS positioning data, as well as electronic mail services. However, this is understood to be inaccurate, with Gonets-M having no role in the GLONASS operation.
The Gonets-M satellites are are upgraded versions of the Gonets satellites, a derivative of the military Strela-3 satellite system. They have a lifetime of five to seven years.