The second stage of the Soyuz-2.1v is the same as the third stage of the Soyuz-2.1b; powered by an RD-0124 engine. For most missions a Volga upper stage will be used to manoeuvre the payload from an initial parking orbit to its final destination. The Volga is derived from the propulsion system of the Yantar reconnaissance satellite, and was developed as a lighter and cheaper alternative to the Fregat.
