Rokot

Rokot ( meaning Rumble or Boom), also transliterated Rockot, was a Soviet Union (later Russian) space launch vehicle that was capable of launching a payload of into a Earth orbit with 63° inclination. It was based on the UR-100N (SS-19 Stiletto) intercontinental ballistic missile (ICBM), supplied and operated by Khrunichev State Research and Production Space Center. The first launches started in the 1990s from Baikonur Cosmodrome out of a silo. Later commercial launches commenced from Plesetsk Cosmodrome using a launch ramp specially rebuilt from one for the Kosmos-3M launch vehicle. The cost of the launcher itself was about US$15 million in 1999; The contract with European Space Agency (ESA) for launching Swarm in September 2013 was worth €27.1 million (US$36 million).

== Specifications == Rokot's total mass was 107 tonnes, its length 29 metres and its maximum diameter 2.5 metres. The liquid-fueled launch vehicle comprised three stages. The lower two were based on the Soviet UR-100N ICBM; the first stage used an RD-0233 / RD-0234 engine complex, while the second stage used an RD-0235. The third stage was a Briz-KM ( meaning Breeze-KM), which has a mass of about 6 tonnes when fuelled, and is capable of flying for 7 hours and reigniting its engine six times during flight, allowing different satellites to be placed into different orbits. All stages used unsymmetrical dimethylhydrazine (UDMH) as fuel and dinitrogen tetroxide (N2O4) as oxidiser. The Strela is a similar rocket, also based on the SS-19.