Soyuz is a family of Soviet and Russian medium-lift launch vehicles that has flown more often than any other orbital rocket line in history. First launched in November 1966 and still in service as the digital-flight-control Soyuz-2, the family has accumulated well over 1,700 flights, and the broader R-7 lineage it belongs to passed 2,000 orbital launches on December 25, 2024.[1][2]
The rocket is inseparable from human spaceflight. A Soyuz launcher carries the Soyuz crewed spacecraft of the same name, which has ferried cosmonauts and astronauts since 1967 and remains Russia's only crew vehicle, flying regular rotations to the International Space Station. Since Western sanctions ended most of its commercial business in 2022, the family flies chiefly for the Russian government: navigation and military satellites, Progress cargo ships, and crewed missions.[1][3]
R-7 heritage
Every Soyuz traces back to the R-7 Semyorka, the world's first intercontinental ballistic missile, designed by Sergei Korolev's bureau and first flown on May 15, 1957. A modified R-7 orbited Sputnik 1 that October, opening the Space Race, and the Vostok derivative carried Yuri Gagarin on the first human spaceflight in April 1961.[2]
The R-7's signature layout survives unchanged: four tapered liquid-fueled boosters clustered around a core stage, all burning kerosene and liquid oxygen and all igniting on the pad. The Soyuz variant, essentially a Voskhod rocket with an improved third stage, first flew on November 28, 1966 to support the new Soyuz spacecraft. Its descendants (Soyuz-L, Soyuz-M, Soyuz-U, Soyuz-U2, Soyuz-FG, and today's Soyuz-2) kept the airframe while upgrading engines and avionics.[1]
Soyuz-U, produced from 1973 to 2017, became the single most-launched carrier rocket ever built, with 786 launches and 765 successes.[1]
Variants
| Variant | Service | Launches | Notes |
|---|---|---|---|
| Soyuz (original) | 1966-1976 | 32 | Introduced for the Soyuz spacecraft |
| Soyuz-U | 1973-2017 | 786 | Most-flown single rocket variant in history |
| Soyuz-FG | 2001-2019 | 70 | Carried crews until replaced by Soyuz-2 |
| Soyuz-2.1a | 2004-present | 81+ | Digital controls; crewed since 2020 |
| Soyuz-2.1b | 2006-present | 84+ | Upgraded RD-0124 third stage engine |
| Soyuz-2.1v | 2013-2025 | 13 | Light version without side boosters |
The current Soyuz-2 replaced the analog control systems of Soviet-era models with digital avionics, allowing larger fairings and roll steering in flight. The 2.1a and 2.1b differ mainly in the third stage engine: the 2.1b's RD-0124 raises specific impulse from 326 to 359 seconds and lifts about 1,200 kilograms more. Together the two main Soyuz-2 models had logged 165 launches with 160 full successes through April 2026, a 97 percent success rate. The optional Fregat upper stage adds multi-burn capability for higher orbits.[3]
Specifications
| Parameter | Soyuz-2.1b |
|---|---|
| Height | 46.3 m |
| Diameter | 10.3 m across boosters (2.95 m core) |
| Liftoff mass | 312,000 kg |
| Boosters | 4, each with one RD-107A engine |
| Core stage | 1 RD-108A engine |
| Third stage | 1 RD-0124 engine |
| Propellants | Kerosene / liquid oxygen |
| Payload to low Earth orbit | 8,670 kg (from Baikonur) |
| Optional upper stage | Fregat or Volga |
Soyuz-2 launches from three sites: Baikonur Cosmodrome in Kazakhstan, Plesetsk in northern Russia, and the newer Vostochny Cosmodrome in the Russian Far East. A fourth pad at the European Space Agency's spaceport in French Guiana hosted 27 Soyuz flights for Arianespace between 2011 and 2022, when the partnership collapsed.[1][3]
Crewed spaceflight role
The Soyuz spacecraft-and-rocket combination is the longest-serving crew transportation system in spaceflight. After the American Space Shuttle retired in 2011, Soyuz was the only way for any nation to reach the International Space Station until SpaceX's Crew Dragon entered service in 2020, and NASA astronauts still fly on Soyuz under a seat-exchange agreement that keeps at least one Russian and one American on each vehicle type. Soyuz MS-28, launched in November 2025, carried NASA astronaut Christopher Williams alongside two cosmonauts.[4]
Crewed flights lift off from Baikonur atop a Soyuz-2.1a fitted with a launch escape tower that can pull the capsule away from a failing rocket at any point from the pad through booster separation. That separation event, in which the four spent boosters peel away symmetrically about two minutes into flight, is visible from the ground as the so-called Korolev cross. The same rocket also launches uncrewed Progress freighters, which have delivered propellant and cargo to Soviet and Russian stations since 1978.[1][4]
The system's crew safety record is strong despite two fatal accidents early in the spacecraft's history (Soyuz 1 in 1967 and Soyuz 11 in 1971, both spacecraft rather than launcher failures). When a booster separation failure destroyed the Soyuz MS-10 launch in October 2018, the escape system pulled the crew capsule clear and both crew members landed unharmed.[1][4]
Current status under sanctions
Sanctions imposed after Russia's 2022 invasion of Ukraine stripped the program of nearly all Western business. ESA suspended Soyuz operations in French Guiana, the OneWeb constellation moved its launches to competitors after Roscosmos impounded 36 of its satellites at Baikonur, and imports of Western microelectronics were cut off, forcing reliance on domestic components.[1][2]
Launch cadence has settled at roughly one flight per month: Russia conducted 17 orbital launches in 2025, about three quarters of them on Soyuz-2, a pace far below the Soviet era but sufficient for GLONASS navigation satellites, military payloads, station crews, and Progress freighters. Russia has committed to the International Space Station partnership through 2028 while it studies a national successor station.[4][5]
Successors
Replacement programs have moved slowly. The Angara family now flies from Plesetsk and Vostochny in light and heavy versions, and the medium-class Soyuz-5 (also called Sunkar under the joint Baiterek project with Kazakhstan) made its first test flight from Baikonur in the spring of 2026 after slipping from December 2025. Even so, Roscosmos expects the classic R-7-derived Soyuz-2 to keep flying crews and cargo well into the 2030s; no successor is yet human-rated.[2][6]
References
- Soyuz (rocket family) - Wikipedia.
- R-7 (rocket family) - Wikipedia.
- Soyuz-2 - Wikipedia.
- List of Soyuz missions - Wikipedia.
- The Ill-Defined Space Global Orbital Launch Summary: 2025 - Ill-Defined Space.
- Soyuz-5 flies its first test mission - RussianSpaceWeb.
