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: well over 1,700 flights since November 1966.[1] Its R-7 lineage passed 2,000 orbital launches on December 25, 2024,[2][7] and the current digital-flight-control Soyuz-2 still launches all of Russia's crewed missions.[1]

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

The major Soyuz variants span six decades, from the original model of 1966 to the Soyuz-2 versions flying today.

VariantServiceLaunchesNotes
Soyuz (original)1966-197632Introduced for the Soyuz spacecraft
Soyuz-U1973-2017786Most-flown single rocket variant in history
Soyuz-FG2001-201970Carried crews until replaced by Soyuz-2
Soyuz-2.1a2004-present82+Digital controls; crewed since 2020
Soyuz-2.1b2006-present85+Upgraded RD-0124 third stage engine
Soyuz-2.1v2013-202513Light version without side boosters; retired 2025

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 the 326 seconds of the 2.1a's RD-0110 to 359 seconds and lifts about 1,200 kilograms more. Together the two main Soyuz-2 models had logged 167 launches with 162 full successes through July 2026, a 97 percent success rate. The optional Fregat upper stage adds multi-burn capability for higher orbits.[3] The light Soyuz-2.1v, a booster-less derivative flown from Plesetsk, made its 13th and final flight in February 2025.[22]

A direct comparison of the two active models:

FeatureSoyuz-2.1aSoyuz-2.1b
Third stage engineRD-0110RD-0124
Third stage specific impulse326 seconds359 seconds
Payload to LEO from Baikonur7,430 kg8,670 kg
Crew launchesYes, since 2020No

Specifications

The workhorse Soyuz-2.1b stands 46.3 meters tall, has a liftoff mass of 312,000 kilograms, and can place 8,670 kilograms into low Earth orbit from Baikonur.[3]

ParameterSoyuz-2.1b
Height46.3 m
Diameter10.3 m across boosters (2.95 m core)
Liftoff mass312,000 kg
Boosters4, each with one RD-107A engine
Core stage1 RD-108A engine
Third stage1 RD-0124 engine
PropellantsKerosene / liquid oxygen
Payload to low Earth orbit8,670 kg (from Baikonur)
Optional upper stageFregat 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.[1][3] 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.[21]

Spacecraft history

The Soyuz spacecraft's career opened in tragedy. Veteran cosmonaut Vladimir Komarov launched alone aboard Soyuz 1 on April 23, 1967, on a mission conceived as a rehearsal of rendezvous techniques for the Soviet lunar programs, with a second crewed launch to follow. After about a day in orbit spent working through technical problems, Komarov steered the ship back toward Earth on April 24, but the parachute system failed and the descent module crashed near Orsk, killing him.[9] He was the first person to die during a spaceflight.[4] Crewed flights resumed after an 18-month stand-down and a parachute redesign with Soyuz 3 in October 1968, whose pilot Georgi Beregovoy rendezvoused with the uncrewed Soyuz 2 but could not dock.[10] In January 1969, Soyuz 4 and Soyuz 5 completed the first docking between two crewed spacecraft, and two cosmonauts spacewalked from one vehicle to the other.[4]

Disaster returned in 1971. Georgi Dobrovolski, Vladislav Volkov, and Viktor Patsayev, a backup crew promoted when a flight surgeon grounded the prime crew, launched on Soyuz 11 on June 6, 1971 and became the first people to live aboard a space station, spending more than three weeks on Salyut and breaking the 18-day endurance record set by Soyuz 9 a year earlier. During their return on June 30, the shock of the explosive bolts that separated the spacecraft's modules jarred open a pressure equalization valve, and the cabin vented to space. Flying without pressure suits, the three men died within minutes; NASA astronaut Thomas Stafford represented the United States at their state funeral.[11] Every Soyuz crew since has launched and landed in pressure suits, which initially meant cutting the crew from three to two; the third seat returned with the Soyuz T generation introduced in 1979.[8][11]

Four years after Soyuz 11, the spacecraft played its part in a thaw. For the Apollo-Soyuz Test Project, the Soviets fitted Soyuz with an androgynous docking unit and flew a full dress rehearsal, Soyuz 16, before the joint mission.[8] On July 15, 1975, Soyuz 19 carried Alexei Leonov and Valeri Kubasov to orbit the same day an Apollo spacecraft launched with Thomas Stafford, Vance Brand, and Deke Slayton. The two ships docked on July 17; Leonov radioed "Capture! Soyuz and Apollo are shaking hands now!" and met Stafford at the hatch for the first international handshake in space. The crews spent about two days docked, sharing meals, experiments, and press conferences, in a mission that helped lay the groundwork for the Shuttle-Mir flights and the International Space Station partnership.[12]

The spacecraft has since been rebuilt inside its familiar three-module shell several times. The Soyuz T of 1979 introduced a digital computer for motion control, the Soyuz TM of 1986 became the ferry for the Mir space station and served through 2002, the Soyuz TMA of 2002 reshaped the cabin to fit a wider range of crew sizes for station service, the TMA-M of 2010 digitized the flight control system further, and the current Soyuz MS arrived in 2016.[8] Along the way, Soyuz TM-31 delivered William Shepherd, Yuri Gidzenko, and Sergei Krikalev to the new International Space Station on October 31, 2000 to begin Expedition 1; people have lived in orbit continuously ever since.[13]

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 under NASA's Commercial Crew Program.[4] The agencies now barter seats with no money changing hands so that at least one American and one Russian are aboard the station even if one vehicle is grounded. The latest extension, confirmed in April 2025, booked NASA astronauts Jonny Kim and Chris Williams on Soyuz flights that year and Anil Menon on Soyuz MS-29 in 2026, with Roscosmos cosmonauts riding Crew Dragon missions in exchange into 2027.[17][18]

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 the two fatal accidents early in the spacecraft's history, Soyuz 1 and Soyuz 11, both spacecraft rather than launcher failures. When a booster separation failure destroyed the Soyuz MS-10 launch on October 11, 2018, the escape system pulled the capsule clear, and NASA astronaut Nick Hague and cosmonaut Alexey Ovchinin emerged unharmed from the ballistic landing downrange.[1][14]

The spacecraft has also weathered a serious failure in orbit. On December 14, 2022, the docked Soyuz MS-22 vented its entire coolant loop into space, a rupture Roscosmos attributed to a probable micrometeoroid strike on the radiator.[16] Judged unsafe for a crewed return except in an emergency, the capsule came home empty, and a replacement, Soyuz MS-23, launched without a crew on February 23, 2023. The swap stretched the mission of NASA astronaut Frank Rubio and cosmonauts Sergey Prokopyev and Dmitri Petelin to 371 days; when they landed on September 27, 2023, Rubio held the record for the longest single spaceflight by an American.[15]

Current status under sanctions

Sanctions imposed after Russia's 2022 invasion of Ukraine stripped the Soyuz 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, 13 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. The year ended with a rare anomaly, when the Fregat upper stage on a December 28 flight appears to have malfunctioned during its sixth burn and released some of its payloads, including prototype Marafon constellation satellites, into an incorrect orbit.[5]

Crewed operations have slowed in step: Soyuz station tours now run about eight months instead of the traditional six, so fewer spacecraft are needed each year.[17] Soyuz MS-28 came home on July 26, 2026, landing Williams and cosmonauts Sergey Kud-Sverchkov and Sergei Mikaev on the Kazakh steppe after 241 days.[19] Its replacement, Soyuz MS-29 with Pyotr Dubrov, Anna Kikina, and Menon aboard, had docked at the station's Prichal module twelve days earlier, a little over three hours after lifting off from Baikonur on July 14; that crew is due back in April 2027.[18]

Russia's commitment to the station itself has firmed up. Having earlier signed on only through 2028, Roscosmos agreed with NASA in July 2026, during the MS-29 launch campaign at Baikonur, to keep the International Space Station partnership and the crew exchange running through 2030.[20]

Successors

Russia's programs to replace Soyuz 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 on April 30, 2026 after slipping from December 2025. Flying from Site 45 at Baikonur, the rocket carried an attached mass simulator on a planned suborbital trajectory ending in a designated zone of the Pacific Ocean, a flight Roscosmos declared successful; the vehicle is intended to take over work once done by the Ukrainian-built Zenit.[6] For the era after the ISS, plans presented in late 2025 call for Russia to undock its segment modules around 2030 and reuse them as the core of a national successor station.[23] 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

  1. Soyuz (rocket family) - Wikipedia.
  2. R-7 (rocket family) - Wikipedia.
  3. Soyuz-2 - Wikipedia.
  4. List of Soyuz missions - Wikipedia.
  5. Space Activities in 2025 - Jonathan McDowell, planet4589.org, February 4, 2026.
  6. Soyuz-5 flies its first test mission - RussianSpaceWeb.
  7. Soyuz launches Resurs-P5 imaging satellite - RussianSpaceWeb.
  8. Soyuz spacecraft - RussianSpaceWeb.
  9. Vladimir Komarov's tragic flight aboard Soyuz-1 - RussianSpaceWeb.
  10. 50 Years Ago, Soviets Return Cosmonauts to Space - NASA.
  11. 50 Years Ago: Remembering the Crew of Soyuz 11 - NASA.
  12. 45 Years Ago: Historic Handshake in Space - NASA.
  13. Space Station 20th: Expedition 1 Crew Launches to the International Space Station! - NASA.
  14. Statement on Soyuz MS-10 Launch Abort - NASA, October 11, 2018.
  15. Record-Setting NASA Astronaut, Crewmates Return from Space Mission - NASA, September 27, 2023.
  16. Russia to launch new Soyuz capsule to replace leaky spacecraft on space station - Space.com.
  17. NASA extends seat barter agreement with Roscosmos into 2027 - SpaceNews, April 13, 2025.
  18. Soyuz Docks to Station, Hatches Open Soon for Crew Greeting - NASA, July 14, 2026.
  19. Soyuz MS-28 Back Home After 8 Months on ISS - SpacePolicyOnline, July 26, 2026.
  20. Russia Agrees to ISS Operations, Seat-Swaps, Through 2030 - SpacePolicyOnline, July 16, 2026.
  21. Soyuz in French Guiana - CNES.
  22. Soyuz-2-1v launches first mission of 2025 - RussianSpaceWeb.
  23. Russia's plans for a space station include 'recycling' its ISS modules - Phys.org, December 2025.