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Vostok Kaluga Museum
Vostok Kaluga Museum

Credit: © Mark Wade. 43,450 bytes. 567 x 310 pixels.

The world's first ICBM became the most often used and most reliable launch vehicle in history. The original core+four strap-on booster missile had a small second stage added to produce the Vostok launch vehicle, with a payload of 5 tonnes. Addition of a larger second stage produced the Voskhod/Soyuz vehicle, with a payload over 6 tonnes. Using this with a third stage, the resulting Molniya booster placed communications satellites and early lunar and planetary probes in higher energy trajectories.

By the year 2000 over 1,628 had been launched with an unmatched success rate of 97.5% for production models. Improved models providing commercial launch services for international customers are even now entering service. It appears the R-7 will easily be in service past the 50th anniversary of its first launch.

Development of the R-7 began in 1950 under research project N-3 "Development requirements for a liquid rocket with a range of 5,000 to 10,000 km and a warhead of 1 to 10 tonnes". The research project was authorised in a decree of 4 December 1960. The study was headed by Korolev's NII-88 but involved a wide range of other Soviet research institutes:

The research program tackled a range of difficult problems to achieve a rocket with the following new technologies:

Following completion of this basic research, work was focused in the successor project N-1, "Theoretical experimental research for a two stage ballistic rocket with a range of 7,000 to 8,000 km". Work on the N-1 was authorised by a decree of 13 February 1953. The objective was to create a draft project for a two stage ICBM with a range of 8,000 km, a warhead mass of 3,000 kg, and a gross lift-off mass of 170 tonnes.

Work was well underway when the requirements were suddenly altered on 3 October 1953. The total warhead mass was increased to 5,500 kg, with the net mass of only the nuclear device itself being 3,000 kg. The rocket designed to that point would have a range of only 5,500 km with such a warhead. A meeting was called of the Chief Designers in January 1954 to discuss how to handle the problem. Several weight saving measures were used. The single engines per module were replaced by small diameter engines of reduced length; the propellant tanks were laid out to minimise mass; a unique launch pad design was accepted that suspended the rocket above the flame pit and shielded it from cross winds, which allowed a lighter structure.

Another technical challenge were the small vernier rockets used to pitch the rocket. These had to have a high specific impulse, gimbal 45 degrees, and deliver a thrust of 2.5 tonnes. Glushko could not deliver an engine with these characteristics, so Melnikov of OKB-1 was assigned the task of designing the engines in-house. The engine that resulted met the requirements and was the technological basis for later rocket engines developed within OKB-1 (the Lox/Kerosene upper stage engines for the Molniya, N1, and Proton boosters).

By February 1954 the stage was reached where a final design was possible. A government declaration of 20 May 1954 authorised development of the two stage R-7 / 8K71 intercontinental ballistic missile. This was followed by a decree of 28 June 1954 'On plans N/R for space research'. Implementation came via a Ministry of Defence decree of 6 July 1954 calling on all industry organisations to work together and assigning the project the highest national priority. The draft project, using much material generated for the T-1 project, was completed in July 1954.

The vehicle in the draft project used the 'packet' layout with a hammerhead core stage surrounded by four shorter booster stages. At ignition, the four booster stages ignited. If full thrust was achieved, the core was then ignited and the booster rose on the thrust of all five stages. The rocket could boost the 5500 kg warhead to 7.9 km/s and 8,000 km range, with a maximum miss distance of plus or minus 10 km. The warhead was the German 'sharp point': a 16 degree cone, 7.27 m long, mounted atop a cylindrical interstage section. The rocket had a gross lift-off mass of 280 tonnes, and an empty mass of 27 tonnes. The first stage burned out at 2,170 m/s and the second stage at 6,385 m/s. Thrust at lift-off was 403.4 tonnes. The R-7 incorporated ingenious solutions in ground handling of the large rocket. The rocket would be assembled horizontally, rolled out to the pad, then raised to the vertical position and quickly fuelled.

The expert commission deemed the decree requirements to be fulfilled and recommended construction of the rocket with minor changes in the development plan. The government authorised the construction phase in a decree of 20 November 1954. The design was frozen by Korolev on 11 March 1955 and drawing release and parts fabrication began. By 20 March 1956 a decree set forth the impending three stage development test plan:

It turned out that the biggest problem was development of the vernier rockets for the first stage. Glushko was uncooperative and special test stands had to be build to test the integrated propulsion system.

In the first half of 1956 work began in earnest at 36 factories with the objective of making the first test flight by the end of the year. The first article completed was a full scale mock-up consisting of the core and one booster stage. Two Block A and B stages were delivered for stand tests, but incomplete factory test equipment held up the start. At that point it seemed impossible that a flight would be made within the year.

By the second half of 1956 solutions had been found to the outstanding problems. Serial production of rockets had begun. The Progress Aviation Factory in Samara, V Ya Litvinov manager, had been selected to fabricate detailed parts but final assembly of the prototype rockets was carried out at Factory 88 in Kaliningrad. Over time the factory at Samara would be organised as the Third Filial of OKB-1 and take over first production, and then engineering, of future R-7 derivatives. In 1974 it became the TsKB, a separate entity.

R-7 systems were developed in the following research program:

Test flights of the first lot of 12 prototype missiles was completed on January 30, 1958. By that time the Soviet Union had used the R-7 to demonstrate the first full-range ICBM and orbit the first two artificial satellites of the earth.

In its intended military mission, the R-7 was quickly overtaken by technological improvements. These allowed the Soviet Union to build missiles using 'zero warning launch' storable propellants and smaller nuclear warheads (Yangel's R-16 and R-36, Chelomei's UR-100). Deployment of the R-7 was very limited, and its service life extended only from 1960 to 1966. Only one dedicated ICBM pad was built at Baikonur, and six to eight in the Angara complex at Plesetsk. By 1966 they were all converted to space launch use and the military service life of the rocket was over.

But as a space launcher, the R-7, with upper stages, became the most successful in history. By the year 2000 over 1,628 had been launched with a success rate of 97.5% for production models.


Launch Vehicle: GIRD.

The Central Committee for the Study of Rocket Propulsion (GIRD) was established in the Soviet Union to develop rocket technology. They launched a series of liquid fuel rockets in the 1930's before many of them ended up in prison during Stalin's purges. Those that survived were released and built the Soviet space and missile programs on the basis of German technology after the war.


Launch Vehicle: RDD.

The RDD - Long range rocket - was assigned to Korolev in November 1944 in response to the German V-2. Korolev was given charge of a team of 60 engineers and required to provide a draft project in three days. The resulting two-stage design used Lox/Alcohol propellants and an autopilot for guidance. It was proposed that a 5 tonne thrust rocket, 110 mm in diameter, would be available by 1945. A 250 tonne thrust, solid fuelled, 280 mm diameter, 4 m long rocket would be ready by 1949. These designs evolved into the more refined D-1 and D-2 before being overtaken by the post-war availability of V-2 technology.


Launch Vehicle: D-1. Korolev design for a 'long range' rocket prior to orders to copy the V-2. The 1000 kg rocket would have a range of 32 km. Wingspan 1.0 m; 370 kg propellants; minimum range 12..8 km; maximum velocity 854 m/s; maximum altitude 12.5 km.

Launch Vehicle: D-2.

Korolev design for a 'long range' rocket prior to orders to copy the V-2. Extended-range winged version of the D-1. The 1200 kg rocket would have a range of 76 km. Wingspan 1.5 m; 370 kg propellants; minimum range 20 km; maximum velocity 628 m/s; maximum altitude 10.7 km.


Launch Vehicle: R-7 8K71.

Initial flight test configuration of the world's first ICBM. 12 launches, of which 4 were devoted to satellites. Built at OKB-1 in Kaliningrad (Korolev). Final assembly, and later production, then was moved to Aviation Factory Number 1, 'Progress', in Kuibyshev (Samara).


Launch Vehicle: Sputnik 8K71PS. Relatively unmodified R-7 ICBM test vehicles used to launch first two Sputniks.

Launch Vehicle: Luna 8K72. R-7 ICBM with single-engine upper stage used for early Soviet unmanned lunar shots.

Launch Vehicle: R-7A 8K74.

Improved version of the R-7 first ICBM, and the one actually deployed to pads in Baikonur and Plesetsk. 15 launches in the flight test series, with 14 successes, from December 1959 to July 1960. These rockets were completed at Aviation Factory Number 1, 'Progress', in Kuibyshev (Samara).


Launch Vehicle: Sputnik 8A91. Modified R-7 ICBM used to launch Sputnik 3.

Launch Vehicle: Molniya 8K78.

On 15 January 1960 Korolev signed the order for development of a four stage rocket based on the R-7. The draft project was completed on 10 May 1960. The original design was intended for launch of unmanned probes toward Mars, but it had universal uses.

The first two stages - the four strap-ons of the first stage and the second core stage - were based on the R-7 ICBM, but reinforced for the heavier upper stages.

On aerodynamic grounds the new third stage had to follow closely the diameter of the Vostok third stage; it could only be increased from the Vostok's 2.58 m to 2.66 m diameter. The new third stage used engines developed for the R-9 ICBM. Although first developed for the Monlniya 4-stage booster, it later would be used with modifications in the three-stage Soyuz launch vehicle.

The fourth stage would have to restart in weightless conditions in an earth parking orbit, presenting a number of problems. It needed to be equipped with an orientation and stabilisation system (SOIS) and a jettisonable engine section (BOZ). The BOZ had to start in weightlessness provide a low thrust to settle the propellants in the main stage so that the main engine could ignite. The stage was based on the existing Vostok third stage, with two toroidal tanks of 600 mm cross section, and a single S1-5400 Lox/kerosene engine.


Launch Vehicle: Vostok 8K72. 8K72 Luna launch vehicle, third stage modified with larger forward cylindrical section to accomodate Vostok-sized spacecraft. Used only for launch of first few prototype Vostoks.

Launch Vehicle: Vostok 8K72K. R-7 ICBM with single-engine third stage, uprated from Luna launch vehicle and with forward fairing to accomodate Vostok/Zenit sized spacecraft. 8K72K, used for Vostok manned spacecraft launches and the first Zenit launch attempt.

Launch Vehicle: MR.

Korolev studied this Multimodular Rocket (MR), based on stages already designed for the 8K74 and 8K77 (R-7 and R-9) missiles. The concept seems to have been promoted in competition with Chelomei's UR-200, for the launcher could be used for similar missions:

  • Military global rocket (orbital bombing system) of unlimited range
  • ICBM
  • Launch vehicle for anti-satellites
  • Space exploration

The three-stage version of the rocket would have a total mass of 101 tonnes, an empty mass of 10 tonnes, and first, second, and third stage thrusts of 140 tonnes, 45 tonnes, and 10 tonnes. An ICBM would be composed of just the first and second stages, and an IRBM from the first stage alone.

As was the case of the 8K74, work on the design was stopped in September 1961.


Launch Vehicle: Molniya 8K78L.

The Molniya 8K78L was designed by Korolev's design bureau for launching a manned spacecraft on a flyby of the Moon and return to earth. To achieve this it would have used Lox/LH2 engines in the third and fourth stages. Preliminary design was completed on 8 July 1962, but such technology was years away in the Soviet Union and the project was not pursued further.


Launch Vehicle: Vostok 8A92. The 8A92 was a modernized version of the Vostok booster used for launch of Zenit-2 reconnaisance satellites.

Launch Vehicle: Polyot 11A59. Two stage version of Vostok 11A57. Used for flight test of prototype Chelomei ASAT after cancellation of UR-200 booster and before availability of Tsiklon.

Launch Vehicle: Voskhod 11A57.

The 11A57 took the large third stage originally developed for the 8K78 interplanetary probe projects and applied it to increasing R-7 low earth orbit performance. It was primarily designed to launch the Zenit-4 reconnaisance satellite, but was also used for the Voskhod manned flights and later for a variety of other Zenit series versions.


Launch Vehicle: Molniya 8K78M. Improved Molniya, in variants with Block ML third stages, used for launch of Molniya spacecraft.

Launch Vehicle: Vostok 11A510.

Version of R-7 launch vehicle with Vostok second stage and unknown third stage used only twice to launch prototype RORSATs. These satellites were originally to have been launched on the cancelled UR-200 launcher, and operational satellites used Tsyklon-2 launchers.


Launch Vehicle: Soyuz 11A511.

Standardized launch vehicle designed to replace a proliferation of earlier models (8K72, 8A91, 8K74, 8K78, 11A57). Designed initially to support launch of the Soyuz complex (7K manned, 9K rocket stage, and 11k tanker) and Zenit-4 reconnaisance satellite. Later 'U' model extended to cover a range of follow-on satellites. Compared to 11A57, the telemetry system was reduced in mass to no more than 150 kg, and engines were cherry-picked for the vehicle core to ensure that specific impulse was no less than 252 seconds at sea level, 315 in vacuum.


Launch Vehicle: Vostok 8A92M. Second generation space systems required injection of lighter but higher-altitude Meteor and other satellite payloads into sun-synchronous orbits. The 8A92M version was developed for this purpose. First use was the Meteor launch on 29 June 1977.

Launch Vehicle: Soyuz 11A514.

Version of Soyuz launcher with increased payload, designed to launch Soyuz R military reconnaisance satellite. Cancelled along with the Soyuz R project in 1966. Unknown differences to standard Soyuz to reach payload requirement of circa 6700 kg to 65 degree orbit.


Launch Vehicle: Soyuz 11A511L. 11A511 with reinforced second stage, large fairing for earth orbit test of LK lunar lander.

Launch Vehicle: Soyuz 11A511M.

The Kozlov filial of Korolev's OKB-1 was tasked with designing the Soyuz 7K-VI manned military spacecraft. In the first quarter of 1967 a substantially revised design was issued. The new spacecraft, with a crew of two, would have a total mass of 6.6 tonnes and could operate for a month in orbit. However the 11A511 launch vehicle could only put 6.3 tonnes into the 65 degree inclination design orbit. This would limit the crew to one. However the military objected to this. A second cosmonaut, without a spacesuit, but with life support systems and consumables would take another 400 kg of payload. In order to meet the military requirements, Kozlov designed a new variant of the Soyuz launch vehicle, the 11A511M Soyuz-M. The project as reformulated was approved by the central committee on 21 July 1967 by the Central Committee of the Communist Party, with first flight to be in 1968 and operations to begin in 1969. However by the end of the year Kozlov's version of the spacecraft and the project had been taken over by Mishin's main office of OKB-1. Development of the 11A511M continued for a time, perhaps to support planned solo flights of the Soyuz 7K-S military variant (cancelled in 1974). Eight of the 11A511M were built and eventually used to launch a few Zenit-4MT reconnaisance satellite missions from Plesetsk in the early (all other Zenit-4MT used the standard 11A511U). The differences compared to the 11A511U are not known, and what (if anything) differentiated these Zenit-4MT missions from others is also a mystery.


Launch Vehicle: Soyuz 11A511U.

Soyuz-U was a standardised, modernised version of the R-7 launch vehicle with higher performance first and second stage engines. Improvements were made to the launch complexes, including unified test-launch ground support equipment. The booster was first used for the Apollo-Soyuz launches. Military applications included Zenit and Yantar military reconnaisance satellites. Soyuz 11A511U used chilled higher density fuel in the core stage to improve payload. This became the most-widely used version, launching a range of military and manned spacecraft for over thirty years.


Launch Vehicle: Soyuz 11A511U2.

Soyuz 11A511U2 used synthetic kerosene ('Sintin') in first stage for launch of premium reconnaisance satellite and manned payloads requiring just a bit more payload than the standard 11A511 could offer. Further use of the 11A511U2 abandoned in 1996 due to Sintin production stoppage. Later Soyuz spacecraft launched on standard Soyuz, with reduced payload and rendezvous with Mir in lower orbit accepted.


Launch Vehicle: Soyuz 11A511U / Ikar. Standard Soyuz universal booster with Ikar upper stage.

Launch Vehicle: Soyuz 11A511U / Fregat. Standard Soyuz universal booster with Fregat upper stage.

Launch Vehicle: Soyuz M.

Rus project was to result in first major propulsion upgrade to R-7 family in forty years, using first stage engines derived from those developed for Zenit second stage to boost performance. It would have permitted launches from Plesetsk with same or greater payload than launch of standard Soyuz-U from Baikonur, permitting move of more launch operations back onto Russian territory. Instead the more modest Soyuz ST / Soyuz FG upgrades were made.


Launch Vehicle: Soyuz ST. Uprated Soyuz booster designed for commercial customers. Upgraded engines, modern avionics, reduced non-Russian content. Can be used with either Ikar or Fregat upper stages.

Launch Vehicle: Soyuz ST / Fregat. Uprated Soyuz booster designed for commercial customers. Upgraded engines, modern avionics, reduced non-Russian content. Uses Fregat upper stage.

Launch Vehicle: Soyuz FG.

Uprated Soyuz booster designed for high performance Russian government missions - delivery of Soyuz and Progress spacecraft to the International Space Station. Upgraded engines, modern avionics, reduced non-Russian content. Unknown differences to Soyuz ST.


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Last update 3 May 2001.
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© Mark Wade, 2001 .