The Soyuz2.1v (, GRAU index: 14A15) known early in development as the Soyuz1, is a expendable Russian small-lift launch vehicle. It is derivative of the Soyuz2 but utilizing a single core stage (no boosters) built around the powerful NK-33 engine, 50-year-old refurbished remnants from the Soviet N1 moon rocket. It is a member of the R-7 family of rockets built by RKTs Progress in Samara. Launches have been conducted from the Plesetsk Cosmodrome in northwest Russia, and are expected to be conducted in the future from the Vostochny Cosmodrome in eastern Russia, and the Baikonur Cosmodrome in Kazakhstan.

Vehicle

The Soyuz2.1v represents a major departure from earlier Soyuz rockets. Unlike the Soyuz2 upon which it is based, it does away with the four boosters used on all other R-7 vehicles. The single first stage core stage is built around the powerful single-chamber NK-33 engine replacing the four-chamber RD-108 along with structural modifications. Since the NK-33 is fixed, the stage is also equipped with complex engine RD-0110R, built of four vernier engines (with four chambers and four nozzles) for thrust vector control. The RD-0110R engines add 230.5 kN thrust and heats the pressurization gases. The NK-33 engines were built in the 1970s for the cancelled Soviet N1 Moon rocket. These surplus engines offer increased performance over the RD-108; however, only a limited number of engines are available. Once the supply is exhausted, the NK-33 will be replaced by the RD-193. In April 2013, it was announced that the RD-193 engine had completed testing. The RD-193 is a lighter and shorter engine based on the Angara's RD-191, which is itself a derivative of the Zenit's RD-170. The second stage of the Soyuz2.1v is the same as the third stage of the Soyuz2.1b; powered by an RD-0124 engine. Most missions will use a Volga upper stage to transfer 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 that is used on many Soyuz2 missions. The Soyuz2.1v was designed to serve lighter payloads with a payload capacity of 2850 kg to a 200 km circular low Earth orbit with an inclination of 51.8° from Baikonur, and 2800 kg to a 200 kilometre orbit at 62.8° from Plesetsk.

List of launches