Engineering:R-7 (rocket family)

Short description: Family of space launch vehicles developed by the Soviet Union (later Russia)

R-7 Semyorka and its variants used as launchers in the early Soviet space program

The R-7 (Russian: Р-7) family of rockets is a series of rockets, derived from the Soviet R-7 Semyorka, the world's first intercontinental ballistic missile (ICBM). More R-7 rockets have been launched than any other family of large rockets.

Under the direction of the rocket pioneer Sergey Korolyov, the Soviet Union during the 1950s developed an ICBM that was capable of delivering a heavy nuclear weapon to American targets. That ICBM, called the R-7 or Semyorka ("Number 7"), was first successfully tested on August 21, 1957. Because Soviet nuclear warheads were based on a heavy design, the R-7 had significantly greater weight-lifting capability than did initial U.S. ICBMs. When used as a space launch vehicle, this gave the Soviet Union a significant early advantage in the weight that could be placed in orbit or sent to the Moon or nearby planets. There have been a number of variants of the R-7 with an upper stage, each with a different name, usually matching that of the payload, and each optimized to carry out specific missions. An unmodified R-7 was used to launch the first Soviet satellite, Sputnik 1, on October 4, 1957, and an R-7 variant, the Vostok, launched the first Soviet cosmonauts, among them Yuri Gagarin, who on April 12, 1961, became the first human to orbit Earth. Other variants include the Voshkod, used to launch reconnaissance satellites, and the Molniya, used to launch communications satellites. A multipurpose variant, the Soyuz, was first used in 1966 and, with many subsequent variants and improvements, is still in service. This family of launch vehicles has carried out more space launches than the rest of the world’s launch vehicles combined.

When Soviet nuclear warheads became lighter, the R-7 turned out to be impractical as a ballistic missile, and there were no other heavy payloads with a military application. However, long-term development has made the rockets useful in the Soviet, and later, Russian space programmes. Their purpose shifted primarily to launching satellites, probes, crewed and uncrewed spacecraft, and other non-threatening payloads. The R-7 family consists of both missiles and orbital carrier rockets. Derivatives include the Vostok, Voskhod and Soyuz rockets, which as of 2022 have been used for all Soviet, and later Russian human spaceflights. The type has a unique configuration where four break-away liquid-fueled engines surround a central core. The core acts as, in effect, a "second stage" after the other four engines are jettisoned. These rockets are expendable.

Later modifications were standardised around the Soyuz design. The Soyuz-2 is currently in use.

The Soyuz-FG was retired in 2019 in favour of the Soyuz-2.1a. R-7 rockets are launched from the Baikonur Cosmodrome, Plesetsk Cosmodrome, Guiana Space Centre (from 2011 to 2022, see Soyuz at the Guiana Space Centre), and the Vostochny Cosmodrome (first launch 2016).

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° Core Stages	Maiden flight	Final flight	Launches			Remarks
						Total	Success	Failure (+ partial)
R-7 Semyorka	8K71	ICBM	1	15 May 1957	27 February 1961	27	18	9	World's first ICBM
Sputnik-PS	8K71PS	Carrier rocket	1	4 October 1957	3 November 1957	2	2	0	World's first carrier rocket Launched Sputnik 1 and Sputnik 2
Sputnik	8A91	Carrier rocket	1	27 April 1958	15 May 1958	2	1	1	Launched Sputnik 3
Luna	8K72	Carrier rocket	2	23 September 1958	16 April 1960	9	2	7	Launched first Lunar probes
R-7A Semyorka	8K74	ICBM	1	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	2	15 May 1960	1 December 1960	4	3	1	Variant of Luna, used to launch prototype Vostok spacecraft
Molniya	8K78	Carrier rocket	3	20 January 1960	3 December 1965	26	12	14	Designed to send payloads out of LEO
Vostok-K	8K72K	Carrier rocket	2	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	3	Unbuilt
Vostok-2	8A92	Carrier rocket	2	1 June 1962	12 May 1967	45	40	5	Used for launching Zenit reconnaissance satellites throughout the 1960s
Polyot	11A59	Carrier rocket	1	1 November 1963	12 April 1964	2	2	0
Voskhod	11A57	Carrier rocket	2	16 November 1963	29 June 1976	300	277	23	Launched crewed Voskhod 1 and Voskhod 2 missions
Molniya-M	8K78M	Carrier rocket	3	19 February 1964	30 September 2010	297	276	21	Improved version of Molniya
Vostok-2M	8A92M	Carrier rocket	2	28 August 1964	29 August 1991	94	92	2	Modified version for launching Meteor weather satellites into higher orbits
Soyuz/Vostok	11A510	Carrier rocket	3	27 December 1965	20 July 1966	2	2	0	Launched with prototype US-A satellites
Soyuz	11A511	Carrier rocket	2	28 November 1966	24 May 1975	30	28	2	Launched several crewed Soyuz missions
Soyuz-B	11K55	Carrier rocket	2	Unbuilt
Soyuz-V	11K56	Carrier rocket	2	Unbuilt
Soyuz-R	11A514	Carrier rocket	2	Unbuilt
Soyuz-L	11A511L	Carrier rocket	2	24 November 1970	12 August 1971	3	3	0	Created to test the LK lunar lander in LEO
Soyuz-M	11A511M	Carrier rocket	2	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	2 or 3	18 May 1973	22 February 2017	786	765	22	Single most launched carrier rocket ever built Used for a number of crewed Soyuz launches
Soyuz-U2	11A511U2	Carrier rocket	2	23 December 1982	3 September 1995	72	72	0	Used for a number of crewed Soyuz launches
Soyuz-FG	11A511U-FG	Carrier rocket	2 or 3	20 May 2001	25 September 2019	70	69	1	Used for crewed Soyuz launches, the final launch was the Soyuz MS-15 on 25 September 2019.
Soyuz-2.1a / STA	14A14A	Carrier rocket	2 or 3	8 November 2004	Active	64	61	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 / STB	14A14B	Carrier rocket	2 or 3	27 December 2006	Active	79	76	2+1p
Soyuz-2-1v	14A15	Carrier rocket	2	28 December 2013	Active	9	8	1p	1st stage uses a completely new design utilizing surplus NK-33 engines from the Moon N-1 launcher and no boosters.

Korolev Cross

Korolev cross, Soyuz TMA-04M

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.

See also

• 1957 in spaceflight
• List of R-7 launches
• Comparison of orbital launchers families
• Soviet rocketry

References

• McDowell, Jonathan. "Launch List - R-7 Family". Jonathan's Space Page. http://planet4589.org/space/lvdb/launch/R-7. 
• Wade, Mark. "Soyuz". Encyclopedia Astronautica. http://www.astronautix.com/lvs/soyuz.htm. 

External links

• Rocket R-7 from S.P. Korolev Rocket and Space Corporation Energia, a Russian rocket and space contractor