# R-7 (rocket family)

The R-7 (Russian: Р-7) rocket family is a series of launch vehicles descended from the Soviet R-7 Semyorka, developed in the 1950s as the world's first intercontinental ballistic missile (ICBM). While the R-7 proved impractical as a weapon, it became a cornerstone of the Soviet and subsequent Russian space programs. Over time, its design was largely standardized into the Soyuz rocket, which continues to operate in its modernized form, the Soyuz-2. More R-7 rockets have been launched than any other family of orbital rockets.

## Background

The R-7, developed by OKB-1 in Kaliningrad, a Soviet design bureau led by rocket pioneer Sergey Korolyov, was the world's first intercontinental ballistic missile (ICBM). Initially designed to deliver nuclear warheads to American targets, it was first successfully tested on 21 August 1957.
The R-7's basic design comprises a central core stage (Block A) and four strap-on boosters (Block B, V, G, and D), fueled by refined kerosene (RG-1), mixed with cryogenic liquid oxygen (LOX) as the oxidizer. Its stage numbering differs from conventional rockets: the boosters are considered the first stage, and the core stage is the second, though they ignite simultaneously at liftoff. The boosters burn for approximately two minutes before jettisoning, while the core stage continues to burn for about five minutes.
The R-7's impracticality as a weapon became quickly apparent. Its huge launch complexes were vulnerable to attack, the 10 hours it took to prepare for launch hindered its operational readiness, and its reliance on a cryogenic oxidizer meant that it could not be left on alert for more than an hour.
However, due to the weight of Soviet nuclear warheads, the R-7 possessed a significantly greater payload capacity than early U.S. ICBMs. This advantage made the R-7 suitable for space launch missions, giving the Soviet Union a substantial head start in the Space Race. An unmodified R-7 launched Sputnik 1, the world's first artificial satellite. With the addition of upper stages, the R-7 spawned numerous variants, each optimized for specific missions. The Vostok variant carried the first human into orbit, Yuri Gagarin. Other variants, such as Luna, Voshkod, and Molniya, were used for lunar probes, reconnaissance satellites, and communications satellites. Later modifications were standardized around multipurpose Soyuz design, first used in 1966. Its modernized version, the Soyuz-2, continues to serve as a workhorse for the Russian space program.
Production of the R-7 family moved to the Progress Aviation Factory in Samara, Russia, in 1959. Over time, complete responsibility for the entire R-7 family shifted from the main OKB-1 office in Kaliningrad to Samara. The design facilities in Samara evolved from an OKB-1 subsidiary into the independent Central Specialized Design Bureau (TsSKB) in 1974. TsSKB and the Progress factory collaborated on the design, development, and production of Soyuz rockets. In 1996, TsSKB and the Progress factory merged to form a single company, Rocket and Space Centre "Progress" (RKTs Progress).
R-7 rockets are launched from the Baikonur Cosmodrome, Plesetsk Cosmodrome, and Vostochny Cosmodrome and were previously launched from the Guiana Space Centre between 2011 and 2022.

## Summary of variants

All the R-7 family rockets are listed here by date of introduction. Most of the early R-7 variants have been retired. Active versions (as of 2022) are shown in green.
| Name | GRAU index | Function | N° Stages | Maiden flight | Final flight | Launches | Launches | Launches | Remarks |
| Name | GRAU index | Function | N° Stages | Maiden flight | Final flight | Total | Success | Failure (+ partial) | Remarks |
| R-7 Semyorka | 8K71 | ICBM | 2 | 15 May 1957 | 27 February 1961 | 27 | 18 | 9 | World's first ICBM |
| Sputnik-PS | 8K71PS | Carrier rocket | 2 | 4 October 1957 | 3 November 1957 | 2 | 2 | 0 | World's first carrier rocket Launched Sputnik 1 and Sputnik 2 |
| Sputnik | 8A91 | Carrier rocket | 2 | 27 April 1958 | 15 May 1958 | 2 | 1 | 1 | Launched Sputnik 3 |
| Luna | 8K72 | Carrier rocket | 3 | 23 September 1958 | 16 April 1960 | 9 | 2 | 7 | Launched first Lunar probes |
| R-7A Semyorka | 8K74 | ICBM | 2 | 23 December 1959 | 25 July 1967 | 21 | 18 | 3 | The only operational ICBM version. Improved range and guidance system. Only 6 launch positions were available. Used as a base for 11A57 and later mods |
| Vostok-L | 8K72L | Carrier rocket | 3 | 15 May 1960 | 1 December 1960 | 4 | 3 | 1 | Variant of Luna, used to launch prototype Vostok spacecraft |
| Molniya | 8K78 | Carrier rocket | 4 | 20 January 1960 | 3 December 1965 | 26 | 12 | 14 | Designed to send payloads out of LEO |
| Vostok-K | 8K72K | Carrier rocket | 3 | 22 December 1960 | 10 July 1964 | 13 | 11 | 2 | Used for crewed Vostok missions First rocket to launch a man into space |
| Molniya-L | 8K78L | Carrier rocket | 4 | Unbuilt | Unbuilt | Unbuilt | Unbuilt | Unbuilt | |
| Vostok-2 | 8A92 | Carrier rocket | 3 | 1 June 1962 | 12 May 1967 | 45 | 40 | 5 | Used for launching Zenit reconnaissance satellites throughout the 1960s |
| Polyot | 11A59 | Carrier rocket | 2 | 1 November 1963 | 12 April 1964 | 2 | 2 | 0 | |
| Voskhod | 11A57 | Carrier rocket | 3 | 16 November 1963 | 29 June 1976 | 300 | 277 | 23 | Launched crewed Voskhod 1 and Voskhod 2 missions |
| Molniya-M | 8K78M | Carrier rocket | 4 | 19 February 1964 | 30 September 2010 | 297 | 276 | 21 | Improved version of Molniya |
| Vostok-2M | 8A92M | Carrier rocket | 3 | 28 August 1964 | 29 August 1991 | 94 | 92 | 2 | Modified version for launching Meteor weather satellites into higher orbits |
| Soyuz/Vostok | 11A510 | Carrier rocket | 4 | 27 December 1965 | 20 July 1966 | 2 | 2 | 0 | Launched with prototype US-A satellites |
| Soyuz | 11A511 | Carrier rocket | 3 | 28 November 1966 | 24 May 1975 | 30 | 28 | 2 | Used for crewed Soyuz launches. |
| Soyuz-B | 11K55 | Carrier rocket | 3 | Unbuilt | Unbuilt | Unbuilt | Unbuilt | Unbuilt | |
| Soyuz-V | 11K56 | Carrier rocket | 3 | Unbuilt | Unbuilt | Unbuilt | Unbuilt | Unbuilt | |
| Soyuz-R | 11A514 | Carrier rocket | 3 | Unbuilt | Unbuilt | Unbuilt | Unbuilt | Unbuilt | |
| Soyuz-L | 11A511L | Carrier rocket | 3 | 24 November 1970 | 12 August 1971 | 3 | 3 | 0 | Created to test the LK lunar lander in LEO |
| Soyuz-M | 11A511M | Carrier rocket | 3 | 27 December 1971 | 31 March 1976 | 8 | 8 | 0 | Built to launch crewed Soyuz 7K-VI spacecraft, eventually used to launch reconnaissance satellites |
| Soyuz-U | 11A511U | Carrier rocket | 3 or 4 | 18 May 1973 | 22 February 2017 | 786 | 765 | 22 | Single most launched carrier rocket ever built Used for crewed Soyuz launches. |
| Soyuz-U2 | 11A511U2 | Carrier rocket | 3 | 23 December 1982 | 3 September 1995 | 72 | 72 | 0 | Used for crewed Soyuz launches. |
| Soyuz-FG | 11A511U-FG | Carrier rocket | 3 or 4 | 20 May 2001 | 25 September 2019 | 70 | 69 | 1 | Used for crewed Soyuz launches. |
| Soyuz-2.1a / Soyuz-ST-A | 14A14A | Carrier rocket | 3 or 4 | 8 November 2004 | Active | 75 | 72 | 2+1p | Used for crewed Soyuz launches from Soyuz MS-16 on 9 April 2020. In August 2019 the booster lofted the uncrewed Soyuz MS-14 into orbit in order to test the spacecraft on the new rocket. |
| Soyuz-2.1b / Soyuz-ST-B | 14A14B | Carrier rocket | 3 or 4 | 27 December 2006 | Active | 90 | 87 | 2+1p | |
| Soyuz-2.1v | 14A15 | Carrier rocket | 3 | 28 December 2013 | 5 February 2025 | 12 | 11 | 1p | 1st stage uses a completely new design utilizing surplus NK-33 engines from the Moon N-1 launcher and no boosters. |
| ↑ Including boosters ↑ As of 22 May 2020 ||||||||||

## Korolev Cross

The Korolev Cross is a visual phenomenon observed in the smoke plumes of the R-7 series rockets during separation of the four liquid-fueled booster rockets attached to the core stage. As the boosters fall away from the rocket, they pitch over symmetrically due to aerodynamic forces acting upon them, forming a cross-like shape behind the rocket. The effect is named after Sergei Korolev, the designer of the R-7 rocket. When the rocket is launched into clear skies, the effect can be seen from the ground at the launch site.