# Soyuz 2.1v

The Soyuz‑2.1v (Russian: Союз‑2.1в, lit. 'Union‑2.1c', GRAU index: 14A15) known early in development as the Soyuz‑1, is an expendable Russian small-lift launch vehicle. It is derivative of the Soyuz‑2 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. Its 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 were expected to be conducted from the Vostochny Cosmodrome in eastern Russia, and the Baikonur Cosmodrome in Kazakhstan, but didn't take place.

## Vehicle

The Soyuz‑2.1v represents a major departure from earlier Soyuz rockets. Unlike the Soyuz‑2 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 (51,800 lb$_f$) 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 was to be replaced by the RD-193, but these plans were never fully realized. 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 Soyuz‑2.1v is the same as the third stage of the Soyuz‑2.1b; 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 Soyuz‑2 missions.
The Soyuz‑2.1v was designed to serve lighter payloads with a payload capacity of 2,850 kg (6,280 lb) to a 200 km (120 mi) circular low Earth orbit with an inclination of 51.8° from Baikonur, and 2,800 kg (6,200 lb) to a 200 kilometre orbit at 62.8° from Plesetsk.

## List of launches

| Flight No. | Date (UTC) | Launch site | Upper stage | Payload | Orbit | Remarks | Outcome |
| 1 | 28 December 2013 13:30 | Plesetsk, Site 43/4 | Volga | Aist 1, SKRL-756 #1/2 | LEO | Maiden flight of Soyuz 2.1v | Success |
| 2 | 5 December 2015 15:08 | Plesetsk, Site 43/4 | Volga | Kosmos 2511 and 2512 | LEO | Earth observation Radar calibration | Partial failure |
| 3 | 23 June 2017 18:04 | Plesetsk, Site 43/4 | Volga | Kosmos 2519 | LEO | Military satellite, possibly geodesy project Nivelir [ru] | Success |
| 4 | 29 March 2018 17:38 | Plesetsk, Site 43/4 | — | Kosmos 2525 (EMKA) | SSO | Earth observation | Success |
| 5 | 10 July 2019 17:14 | Plesetsk, Site 43/4 | Volga | Kosmos 2535 to 2538 | LEO | Geodesy | Success |
| 6 | 25 November 2019 17:52 | Plesetsk, Site 43/4 | Volga | Kosmos 2542 & 2543 | LEO | Satellite inspection | Success |
| 7 | 9 September 2021 19:59 | Plesetsk, Site 43/4 | Volga | Kosmos 2551 (EO MKA №1) | SSO | Reconnaissance | Success |
| 8 | 1 August 2022 20:25 | Plesetsk, Site 43/4 | Volga | Kosmos 2558 (Nivelir №3) | PO | Surveillance | Success |
| 9 | 21 October 2022 19:20 | Plesetsk, Site 43/4 | Volga | Kosmos 2561 & 2562 | SSO | Surveillance | Success |
| 10 | 29 March 2023 19:57 | Plesetsk, Site 43/4 | — | Kosmos 2568 (EO MKA №4) | SSO | Reconnaissance | Success |
| 11 | 27 December 2023 07:03 | Plesetsk, Site 43/4 | — | Kosmos 2574 (Razbeg №1) | SSO | Reconnaissance | Success |
| 12 | 9 February 2024 07:03 | Plesetsk, Site 43/4 | — | Kosmos 2575 (Razbeg №2) | SSO | Reconnaissance | Success |
| 13 | 5 February 2025 03:59 | Plesetsk, Site 43/4 | Volga | Kosmos 2581-2583 (MKA B1-3) | PO | Un­known | Success |