Intercontinental ballistic missile R-7 ( 8K71 ) / R-7A ( 8K74 )

The world's first intercontinental ballistic missile R-7 (8K71) carried a thermonuclear warhead and could deliver it almost anywhere in the territory of a possible enemy. Preliminary studies on the creation of such a missile began in 1950, while working on the theme H3 "Study of the prospects for the creation of various types of radar with a range of 5000-10000 km with a mass of combat units of 1-10 tons. The theme was carried out by the Decree of the Council of Ministers of the USSR on December 4, 1950. The leading scientific and production organizations of the country were involved in the work: OKB-1 Research Institute-88 (S.P.Korolev), OKB-456 (V.P.Glushko), Research Institute-885 (M.S.Ryazansky, N.S.Ryazansky). A.Pilyugin), NII-3 (V.K.Shebanin), NII-4 (A.I.Sokolov), CIAM, TsAGI (A.A.Dorodnitsyn, V.V.Struminsky), NII-6, NII-125 (B.P.Korolev).  A.N.Steklov Mathematical Institute (M.V.Keldysh) and others. At performance of a theme the wide range of problem questions at that time has been investigated and ways of their decision are planned, the basic possibility of creation of "compound" ballistic missiles with useful load 3-5t, working on components "liquid oxygen - kerosene" is proved, the detailed analysis of the scheme of a rocket, its optimum parameters, number of steps, initial mass, traction of engines and other characteristics is spent.

Continuation of the H3 theme was the T-1 theme "Theoretical and experimental studies to create a two-stage ballistic missile with a range of 7000-8000 km". The work was conducted in accordance with the Decree of the Council of Ministers of the USSR on February 13, 1953. Within the framework of this theme the development of a sketch design of a two-stage long-range ballistic missile with a mass up to 170 t with a detachable head part weighing 3 t for a range of 8 thousand km was carried out. However, in October 1953, by order of the Deputy Chairman of the Council of Ministers of the USSR V.A.Malyshev, the mass of the head unit in the project was increased to 5500 kg (by that time the problem of creating thermonuclear charges with high power density had not been solved yet), while maintaining the flight range, which required a serious reworking of the project (as with the head unit of such mass the designed missile could provide a range of no more than 5500 km).

In January 1954, a meeting of Chief Designers (S.P.Korolev, V.P.Barmin, V.P.Glushko, B.M.Konoplev, V.I.Kuznetsov, N.A.Pilyugin) with participation of M.I.Borisenko, K.D.Bushuyeva, S.S.Kryukova and V.P.Mishin was held, where the issue of further work on the missile in connection with the increase in the mass of the head part was discussed. At the meeting it was decided to use the engine of relatively small size unified for all blocks, limit the size of the blocks that allow their transportation by rail. Due to operating conditions it was decided to abandon the usual launch pad and create a system of ground equipment with unconventional method of missile suspension on special discarded trusses, which reduced the load on the lower part of the missile and reduce its weight. To ensure the specified accuracy of firing, the engine thrust pulse dispersion should have been in a strictly fixed range, however, at the stage of conceptual design OKB-456 failed to solve this issue. At that time, it was decided to use steering chambers as control elements for the first time, which would provide the final thrust stage after the main marching engine was shut down and the required thrust pulse. Due to V.P.Glushko's failure to develop steering motors, this work was entrusted to S.P.Korolev, the Head of the Department of OKB-1 Research Institute-88 M.V.Melnikov (later, when creating on the basis of R-7 launch vehicles, steering motors developed in OKB-456 were used).

May 20, 1954 was adopted a joint resolution of the Council of Ministers of the USSR and the CPSU Central Committee to develop a two-stage ballistic missile R-7 (8K71). The Resolution determined: the main developer of OKB-1 NII-88 and co-executters: OKB-456 (engines), NII-885 (control systems), GSCBspetsmash (ground equipment), NII-10 (gyro devices), KB-11 (special charge) and NII-4 MO (polygon tests). Resolution of June 28, 1954. "On the Research Plan for Special Products, the content, procedure and timing of work on the R-7 missile were specified. The order of the Minister of Defense Industry of July 6, 1954 particularly emphasized that the creation of R-7 missile is a task of national importance and all work should be completed in the specified time frame. S.P.Korolev, who headed OKB-1 NII-88, was given wide powers to attract not only specialists from different industries, but also to use the necessary material resources. The conceptual design of the R-7 missile system was ready in mid-July 1954. Such rapid pace was largely achieved through the use of the T-1 subject.

November 20, 1954 the submitted draft design of the R-7 (8K71) missile was approved by the Council of Ministers of the USSR. In November 1954, a meeting was held at Design Bureau-1 with the participation of K.N.Rudnev, V.P.Barmin, N.A.Pilyugin, M.S.Ryazansky and the customer representatives. The meeting considered the proposal of Design Bureau-1 to assemble the missile package not vertically on the launch facility, as provided for in the design studies, and horizontally in the assembly housing, followed by hanging in its assembled form in the launch system for power units on the side blocks. The proposal was met with ambiguity: it was necessary to break the already established mechanism of work organization, but the arguments in favor of the proposal were so weighty that all doubts disappeared by themselves. On March 20, 1956, the USSR Council of Ministers adopted a Resolution on measures to ensure testing of the R-7 missile and other measures to create favorable conditions for its development. The pace of work on the development of the R-7 rocket sharply increased, and with it the load on performers, for whom were introduced chord pay and additional bonuses.

In addition to working documentation for the regular missile was created documentation for full-size models for experimental testing of all missile systems. In 1956, was produced by two sets of blocks A (central) and B (one of the side) for bench tests and three models for ground testing. At the same time was produced the first flight model, factory control tests which were conducted in the branch number 2 NII-88 (later NII-229). Despite all the difficulties, the first flight sample of the R-7 missile was sent to the test site in late 1956. In the second half of 1956 it was decided to connect to the serial production of R-7 missile Kuibyshev Aviation Plant "Progress" (AY Linkov). The first rockets at the plant "Progress" were assembled from parts and components manufactured at plant number 88. Later at the plant "Progress" was organized branch of Design Bureau-1 headed by Deputy Chief Designer D.I.Kozlov.

The novelty of the missile design, the new principles of construction of the launcher required a significant amount of experimental testing of the missile systems and the missile as a whole. It was required to conduct and training services of the newly created range. For this purpose, a comprehensive test programme is being developed, including:

• Testing of the developed radio control system of R-7 missile in real flight conditions on R-5R missile. Instead of the head unit, a container with R-7 onboard equipment was installed on R-5R missile. From May 31 to June 15, 1956, three successful launches of R-5R rocket were conducted.
• Tests in real flight conditions of the R-7 missile control system included: the system of simultaneous emptying of tanks of the central unit, the system of regulation of apparent speed; the system of normal and lateral stabilization, telemetry system "Tral" and the control system "Torch". The development was carried out on the M5RD rocket at the GTP in two stages with five launches each (the first stage from February 16 to March 23, 1956, the second - from July 20 to August 18, 1956). The test results were assessed as "positive".
• Development of the shockless rocket output from the launch system, at the Leningrad Metal Plant (LMZ). At the LMZ there were concrete wells with a diameter of 19m, intended in due time for manufacturing of gun turrets, and two 300-ton cranes. These tests allowed to carry out the control assembly and to check the functioning of all systems and units of the new launch unit (RU) "Tulip", to check the shockless rocket output from the RU. Tests were carried out with a mock-up of the rocket R-7SN, which allowed to fill the tanks with water with anti-corrosion additive. To do this, the rocket was installed in the launcher, refueled to the starting mass and lifted (imitation launch) by two cranes on a special traverse, attached to the power heads of the side blocks. The speed and angles of the elements of the launcher leaving the rocket (lower guides), support trusses, cable mast, etc. were measured. Processing of the measurements by recalculating the experimental data, despite the lack of completeness of the simulation of the launch (the difference in speeds of the rocket exit from the launcher and other parameters), made it possible to draw a conclusion about the shockless exit of the rocket from the launcher in real launch. The Leningradsky Metallichesky Zavod (LMZ) has also worked out the technology of assembling the rocket from transportable blocks into a "package", the methodology and technology to install the rocket on the launcher, transfer its mass to support farms, verticalization and turning the rocket at a given angle. Tests were conducted from June to September 1956, after which the launcher and the rocket R-7SN were dismantled to send them to the range. In early December 1956 the R-7SN rocket arrived at the range.
• Fire tests of missile blocks and missiles as a whole (from July 1956 to March 1957) on the stand base of branch number 2 NII-88. The tests included cold tests of single blocks for the purpose of testing the modes of filling and feeding the tanks with liquid oxygen and nitrogen, obtaining data on the temperature conditions in the tanks, fuel lines and compartments of the blocks, as well as fire tests of single blocks to check the modes of starting and operating of the marshal and steering engines as part of the engine unit, checking the performance of the engine power supply systems, obtaining data on the temperature and vibration loads on the structural elements of the blocks, checking the real dynamics of the engine. There were five fire tests of three side blocks (August 15, September 1 and 24, October 11 and December 3, 1956), three tests of the central unit (December 27, 1956. (block 2CS), 10 and 26 January 1957. (Block 1CS)) and fire tests of two missiles assembled into a "package" (February 20 - "package" 2C, March 30, 1957 - "package" 4CL - flight version). The fire tests of all three side blocks were satisfactory. The propulsion systems were launched in accordance with a given cyclogram. In preparation for fire tests of the first central unit after oxygen filling there was an accident: a tunnel pipe of oxygen supply to the engine was destroyed because of hydro shocks. The cause of the accident was overheating of liquid oxygen in the tunnel pipe due to its long length. In order to eliminate this shortcoming, a continuous oxygen flow from the bottom of the pipeline to the outlet was introduced, which was later replaced by a circulation system. After the repair and rehabilitation work, the tests were continued and gave positive results. The first test of the rocket continued for only 20 seconds due to the reduced fueling with fuel components. During the following tests, the operating time of all engine units corresponded to their operating time during the flight, and the on-board flight control system deflected the steering chambers to the maximum angles. In parallel with the fire tests, a special stand was used to test the unlocking of ground communications and the technology of maintenance of the missile's tail compartments at launch, which resulted in corrected operating documentation.
• Development of the launch vehicle service cabin and check of its interface with the tail compartments of the rocket blocks. These works were carried out in branch No.2 of NII-88. Their purpose was to test all the mechanisms of the cabin service, methods of its deployment and diversion into the niche, as well as checking the possibility and convenience of maintenance of the tail compartments of the missile from the sites of the cabin. For this purpose, a special installation was assembled, which included a real cabin service and models of the tail parts of the missile blocks. In the process of testing the cabin was repeatedly extended from the niche, lifted its platforms, folding out and connected to the tail sections of the rocket refueling hoses, as well as folding and evacuating the cabin in the niche. At the end of these works the cabin was sent to the range for mounting on the launch system.
• Development of the system of separation of the side blocks of the rocket from the central unit on a special installation in the branch № 2 of NII-88. The purpose of these works was to determine the real characteristics and parameters of the separation system of blocks. The measurement results showed that the separation system functions normally and its parameters do not exceed the design values.
• Development of technology for missile preparation for launch and interaction of services of the range. In December 1956 the first R-7SN missile for fitting and debugging works arrived to the range. The program of these works, as part of the overall comprehensive program of testing of the R-7SN missile, provided for implementation:
  • at the technical position - the full scope of all mechanical assembly work with the rocket, checking the tightness of all the lines of the rocket, checking the ease of maintenance of the rocket systems from ground equipment units and working out technical documentation for the preparation of the rocket and training calculations;
  • at the launch position - transportation of the rocket, its lifting to the vertical position and installation on the launch device, verticalization and aiming, connection of all pneumatic and hydro-communications to the rocket, filling of the rocket with fuel components, All pre-launch operations (lowering of service farms, removal of the service cabin to a niche), firing of air and hydro pads from the missile, discharge of fuel components and evacuation of the missile from the launch position, development of technical documentation and training of combat calculations. The readiness of all services at the range was monitored during this work. Tests were conducted between December 1956 and February 1957.

In December 1956, airplanes flew all the points of the polygon measuring complex located along the flight route and in the area where the head unit fell. In March 1957, the first R-7 missile (No.5) arrived at the technical position of the range for the LKI. The process of missile preparation provided for electric and pneumatic testing of each block, checking the alignment of the rocket blocks after transportation, assembly of the package, conducting electric and pneumatic testing of the missile as a whole (stand-alone and complex tests), installation of pneumatic and hydraulic blocks on the rocket blocks for connection at the launch complex of land routes, repositioning the "package" on the installer and docking the head end. In comparison with the previously developed "products" (ballistic missiles R-1 (8Zh38, adopted by the Soviet Army in 1950, designer S.P. Korolev), R-2 (designer S.P. Korolev), R-5, R-11) the scope and complexity of the test program was unprecedented.

On April 10, 1957, the first meeting of the State Flight Test Commission, approved by the Council of Ministers of the USSR on August 31, 1956, was held, consisting of V. M. Ryabikov (Chairman), M. I. Nedelin (Deputy Chairman), S. M. Ryabikov (Chairman). P.Korolev (Technical Director), V.P.Barmina, V.P.Glushko, V.I.Kuznetsov, A.G.Mrykin, N.A.Pilyugina, M.S.Ryazansky (Deputy Technical Director), S.M.Vladimirsky, A.I.Nesterenko, G.N.Pashkov, I.T.Peresypkin and G.R.Udarov. S.P.Korolev at the commission meeting reported on the results of the experimental testing and preparation of the R-7 missile to start flight tests. Positive results of firing stand tests of blocks and the missile as a whole were the weighty arguments about the readiness of the missile for flight tests. In his report, S.P.Korolev also raised the issue of the structure of test calculations and their personnel, the scheme of control of the responsible operation of preparing the rocket for launch ("executive controller of the test department - controller of the Chief Designer"), which in future work, especially in the preparation of manned space complexes, has found wide application. The flight tests faced the task of checking the correctness of the principal decisions embedded in the design of the rocket, engines, control systems, ground equipment complex, their development and testing in flight conditions, obtaining and accumulating experimental data on the range and heap during launches to the calculated range of about 6300 km, as well as experimental data on all systems and units of the rocket, the complex of ground equipment and measuring instruments. Proceeding from these tasks, the objectives of the first launches were the development of launch technology, the dynamics of the controlled flight of the 1st stage and the process of separation of stages, and subsequent - check and development of radio control system, the dynamics of the flight of the 2nd stage and the movement of the head unit to the target. In addition, two of the twelve missiles designed for flight and design tests, after appropriate modifications, were used to launch the first two artificial satellites of the Earth type "SAR". ("The Simple Companion")

The second stage began on May 5, 1957, when the R-7 No.5 missile was taken to its starting position. The work to prepare the rocket for launch at the launch position, given the novelty and responsibility, was broken down into several days, in particular, filling the rocket with fuel components was scheduled for the eighth day. The first launch took place on May 15, 1957 at 19:01 Moscow time. According to visual observations, the flight proceeded normally up to 60s, then in the tail compartment began to notice changes in the flames of exhaust gases from engines. Processing of the telemetry information showed that the side block D fell off for 98s flight and the rocket lost its stability. The cause of the accident was the leaky fuel line. Despite the failure, this launch allowed to obtain experimental data on the dynamics of the launch and controlled flight of the 1st stage.

The second start-up, scheduled for June 11, 1957, failed despite three attempts: at the first two attempts, due to freezing of the main oxygen valve of the block B, the start-up circuit was reset; at the third attempt, the engine units were shut down in the preliminary stage mode due to an error made at the technical position during the installation of the nitrogen purge valve of the central unit oxidizer line. The rocket was removed from the starting device and returned to the technical position.

The third launch took place on July 12, 1957 at 15.53 min. At 33 seconds of flight the rocket lost its stability. The cause of the accident was a short circuit on the body of the control signal chains of the integrating device through the rotation channel.

The fourth launch on August 21, 1957 at 15:25 was successful, and the missile first reached the target area. The main drawback of this launch was the destruction of the head part in dense layers of the atmosphere in the descending section of the trajectory, and there were no experimental data on the causes of this destruction, because the telemetry records stopped 15-20s before the head part fell. The analysis of the fallen elements of the head part structure allowed to establish that the destruction began with the tip of the head part, and at the same time to clarify the values of its thermal protection coverage. This allowed to finalize the documentation for the head part, to clarify the layout, design and strength calculations and produce it in the shortest possible time for the next launch. On August 27, 1957, the mass media published the TASS report that an intercontinental ballistic missile was tested in the Soviet Union.

The fifth launch of the R-7 missile on September 7, 1957 mainly confirmed the results of the previous launch.

Positive results of rocket flight in the active part of the trajectory allowed to use them for launching the first two artificial satellites of the Earth (of "SAR" type). Rockets No. 1PS and No. 2PS were used as their carriers, which were modified to take into account the tasks being solved. In general, the launch of the first two artificial satellites was decided successfully: on October 4, 1957 the first artificial satellite was put into orbit and on November 3 of the same year a satellite with the first living creature in orbit - a dog called Laika was put into orbit. The R-7 rocket became a "working horse" of the national cosmonautics for many years. It was not only the first intercontinental rocket, but also the first launch vehicle. The rocket based on R-7 ICBMs without additional upper stages was named "Sputnik". According to the results of the first six launches of R-7 rocket were modified head end (replaced by a new one) and its separation system, applied slot antennas telemetry system "Tral", etc., the effectiveness of which was confirmed by subsequent launches. Flight design tests of the second stage were completed with the launch of missiles R-7 May 24 and July 10, 1958, with the first fully successful launch of the rocket R-7 March 29, 1958, the rocket was equipped with a prototype of the standard HC M1-6A. The program of flight and design tests of experimental missiles R-7 was mainly carried out. Experimental data showing the correctness of the main principle decisions embedded in the design of the rocket, engines and control system were obtained. Launch technique, dynamics of controlled flight on the 1st and 2nd stages, radio control system and head end separation were tested. Measures have been checked and implemented to ensure that the head end is reached. Experimental data on the actual flight path to a given range were obtained and the accepted warranty reserves of fuel components are sufficient. However, the obtained dispersion data were not sufficient for a complete assessment of the heap, although the preliminary assessment showed that the dispersion did not exceed the limits accepted in the design. The obtained data on the elastic fluctuations of the design and pressure in the propulsion systems with a frequency of 10-13 Hz per 1 flight step were not sufficient to provide an exhaustive answer to this question.

In general, the R-7 missile, taking into account the elimination in due time observations and shortcomings identified and not eliminated during the tests, was allowed to the next stage of flight tests. The purpose of these tests were to verify the main flight and performance characteristics of the R-7 ICBM (design of the third stage) to the requirements of the Resolution of May 20, 1954; to verify the correctness and sufficiency of the design decisions taken on the basis of the results of the LKI of R-7 missiles of the second stage and determining the reliability of missiles, the specified range and accuracy of firing, and to issue recommendations on the possibility of adopting the design of the third stage for service with the Soviet Army.

Joint flight tests were conducted from December 24, 1958 to November 27, 1959. Tests were conducted on 16 missiles, of which eight were manufactured at the production plant "Progress". Tests were preceded by control fire test bench special assembly, consisting of a central and one side block, held in August-November 1958. at the stands of the branch number 2 Research Institute-88. Testing November 17, 1958., on which the side block was attached to the scheme "package", confirmed the effectiveness of measures to eliminate resonance vibrations in the loop "elastic structure - the propulsion system", which previously led to the destruction of the missile. On the missiles of the third stage the inter-tank instrumentation compartment on the central unit was eliminated (the instrumentation was placed in a single unit in the upper part of the units), steering motors of increased thrust and improved scheme of their power supply were introduced, SOBIS instead of SOBIS (for simultaneous emptying of all tanks on each unit and synchronization of their emptying within specified limits), the conditions of tanks inflation were changed and a number of other structural improvements were applied. Of the 16 missiles launched, 10 reached the target with the given accuracy, two missiles exceeded the range due to deviations in the control system, one missile did not reach the target 28 km due to abnormal operation of the oxidizer charge pipeline at the final stage, one missile flew the target at 16.8 km due to unstable operation of the radio control system and two missiles stopped flying due to deviations in the propulsion system.

Simultaneously with the LKI, space launch vehicles (Sputnik and the new Vostok LVs, with the third stage (Block E)) were launched on the basis of R-7 missiles of the third stage (May 1958 - November 1959). A new Soviet satellite with a record 1327 kg mass and a large number of scientific equipment was injected into orbit. In 1959 Vostok LV provided sending of automatic interplanetary stations to the Moon.

In addition, during the development of Vostok LV it was possible to solve very important scientific and technical problems: the launch of rocket engines in vacuum and weightlessness or alternating loads. Subsequently, the Vostok LV provided for the launch of the world's first spacecraft "Vostok-1" on April 12, 1961, which was piloted by the first astronaut, a citizen of the USSR Yuri Gagarin. Improved "Voskhod" and "Soyuz" boosters (with a new more powerful third stage "Block I") and "Lightning" (with the third stage "Block I" and the new fourth stage "Block L") were created, with the help of which many new achievements were made both in manned and in automatic cosmonautics. Thus, the R-7 ICBM-based boosters raised the Soviet Union's authority to unprecedented heights. New modifications of Soyuz boosters are still in operation, becoming the most reliable rocket in the history of astronautics. A significant role in the modernization of R-7 type missiles belongs to Kuibyshev (now Samara) branch of OKB-1, and then to the CSKB (D.I. Kozlov) and Progress plant, which produces these missiles. The fourth stage "block L" since 1965 was supervised and manufactured by the Lavochkin NPO.

Of particular interest is the creation of a thermonuclear head unit for the R-7 missile. Initially the ICBM was supposed to be equipped with a RDS-6s thermonuclear charge (the world's first combat-ready thermonuclear charge and the first domestic thermonuclear charge; the authors of the idea are A.D. Sakharov, KB-11 employee and V.L. Ginzburg, USSR Federal Institute of Nuclear Sciences employee - see photo). It was necessary to exclude the use of lithium deuteride-tritide in this charge due to tritium deficiency and significant deterioration of performance characteristics of the charge in case of tritium use. It was also necessary to increase energy output of the charge.

However, the assessments showed that a DDS-6s type charge with the required capacity would have extremely large mass and dimensions. That is why it was decided to study the possibility of increasing the power of RDS-6s in its bastritis variant at the expense of application of additional considerable mass of fissile materials. This charge was given the designation RDS-6cD. In the course of its development it gradually became clear that on the way of using the physical scheme of RDS-6s charge it is impossible to solve the problem of creating a highly effective thermonuclear ammunition of necessary power.

The development of powerful thermonuclear charges according to the new two-stage scheme made it possible to abandon the way of their creation according to the single-stage scheme - the two-stage scheme of thermonuclear charges made it possible to sharply increase the specific power of ammunition, i.e. the ratio of ammunition power to its mass. The developed RDS-37 charge (the charge for the first domestic two-stage thermonuclear bomb, based on the idea of "nuclear implosion"; the authors of the idea are the employees of KB-11 V.A. Davidenko and A.P. Zavenyagin - see photo), although it met the requirements for power generation for R-7 ICBMs, required serious modernization. From the very beginning, the development of the new charge began to have an acute competitive character between the options being developed at the country's two main nuclear centers, QB-11 (now VNIIEF, Sarov) and NII-1011 (now VNIITF, Snezhinsk). For example, in 1956 alone the KB-11 conducted 5 tests of thermonuclear devices in order to improve the DDS-37 charge pattern. However, the problem could not be solved, and in three tests the failure of thermonuclear units was received, which was a serious blow, testifying to the insufficiency of the then available ideas about the processes occurring in the RDS-37 type charges. At the same time, based on the RDS-37 design, the Research Institute-1011 was developing powerful thermonuclear charges. In April 1957, the Research Institute-1011 at the Semipalatinsk test site conducted tests of two thermonuclear charges, which generally showed good results. The tests were conducted with a specially reduced energy output for safety reasons.

The following decision was made based on the results of the conducted work:

1. "to accept for carrier R-7 the charge KB-11, consisting of the thermonuclear unit NII-1011 and the primary nuclear charge on the basis of RDS-4 (the first domestic charge for tactical nuclear bombs - see photo);
2.  tests to be carried out at full explosion capacity" (see photo).

The charge for the R-7 missile was tested in the bomb housing. Due to the calculated high power of the thermonuclear charge and in accordance with the decision to conduct a full-scale test, the explosion was carried out at the Northern Firing Range (Novaya Zemlya archipelago). October 6, 1957 the charge in the body of the bombshell was dropped from the distant bomber Tu-16. The test was a complete success - the power of thermonuclear charge explosion received after data processing was 2.9 Mt and exceeded the calculated one by 20%. After a significant improvement of this type of charge, including an increase in the blast power (this was due to the relatively low accuracy of the first ICBM and caused a corresponding decrease in range due to an increase in the mass of the charge), it was adopted for service with the 8K71 ICBM missile system.

In addition to extensive ground-based laboratory and design testing, flight and design tests were conducted to determine the state of the missile's structure, its temperature effect on it, and the movement and deformation of its components under the conditions of real overloads and temperatures during the flight of the R-7 missile. During the flight and design tests, the relevant telemetry information was transmitted to ground registration systems. The flight tests showed that the integrity of the RF structure and the charge, the magnitude of overloads, temperature effects and displacements of the structural units were within acceptable limits. In general, it allowed to draw a conclusion about high reliability of the R-7 missile.

However, already in 1957 the development was completed, and in 1958 the first full-scale test of a new type of thermonuclear charge, called "product 49", was conducted. The ideologists of this project and the developers of the physical scheme of the charge were the employees of KB-11 Yu.A. Trutnev and Yu. The peculiarity of the new charge was that it managed to use the basic principles of the RDS-37 charge:

• to significantly reduce overall parameters due to the new original solution to the problem of X-ray radiation transfer, which determines the implosion of the thermonuclear node;
• to simplify the "layered" structure of the thermonuclear node, which proved to be an extremely important practical solution.

According to the conditions of adaptation to specific carriers, "product 49" was developed in a smaller size and weight category as compared to the RDS-37 charge, but its specific volume energy output was 2.4 times higher. The "primary atomic charge" (according to the classification of that time, the designation of the primary nuclear node or trigger is now used) for "article 49" was tested independently as early as 1957. During its development, it was possible to significantly reduce the size of the node by 1.5 times, while ensuring its sufficiently high energy release. In 1958, KB-11 conducted 8 tests of devices based on "product 49", their power output was in the range from 0.2 to 2.8 Mt.

As a result, at the end of 1958, KB-11 tested a new thermonuclear charge based on the "article 49" design to equip it with an upgraded R-7A ICBM (see photo). Compared with the charge developed earlier to equip the R-7 ICBM, while maintaining the energy release level, mass parameters of the charge were radically reduced (e.g., the charge diameter was reduced by 1.75 times). A charge with gas tritium-deuterium bubbling (strengthening of fission reaction by "thermonuclear" neutrons) was used as a primary nuclear charge. The thermonuclear charge modified as a result of tests was later adopted as a part of the complex with R-7A rocket.

By the Resolution of the Council of Ministers of the USSR dated January 20, 1960, the intercontinental ballistic missile R-7 (8K71) was adopted for service with the Soviet Army. However, even during the work on the R-7 missile it became clear that the missile had a potential for improvement. Thus, from December 24, 1959 began flight and design tests of the improved R-7A (8K74) missile with a new design head (a new, lighter thermonuclear charge 46A, which, in addition to the mass dimensional characteristics, met all trajectory effects and operational requirements) and an improved radio control system. The missile's range of flight was significantly increased. Mass-saving technologies have been applied. The methodology of preparing the missile for launch was also simplified. The task to develop a new missile OKB-1 received July 2, 1958, when it was approved by the Council of Ministers of the USSR. During the LKI eight missiles were tested, of which seven fulfilled their task. R-7A missile was adopted in service on September 12, 1960, replacing the R-7 missile. According to available data, R-7A missile was never on active duty, unlike R-7A (the latter was removed from service in 1968, the maximum number of ICBMs of this type, simultaneously standing on active duty - no more than 5 pieces). However, the R-7A failed to achieve a noticeable improvement in combat and performance characteristics compared with the R-7A. It quickly became clear that the R-7 and its modification could not be placed on combat duty in mass numbers. To base these missiles, construction of a combat launch station (Angara object) began in January 1957 near the settlement of Plesetsk (Arkhangelsk region, RSFSR).

According to other data, after the completion of tests of the first complex with the R-7 missile, the question arose about the organization of military units armed with this type of powerful weapon, which could hit the enemy almost anywhere in the world. The first unit in the armament of which the intercontinental missile system R-7 was put in service was the military unit bearing the conventional name of the object "Angara" (in accordance with the Decree of the CPSU Central Committee and the Council of Ministers of the USSR of January 11, 1957). The commander of the unit was Colonel M.G. Grigoryev.

In the summer of 1959, for the first time in the Armed Forces, a training and combat launch from the starting position was held at the Angara facility. The first launch of the MKR R-7 of serial production was made on July 30, 1959. On December 13, 1959, members of the State Commission signed an act of acceptance into service of the first in the USSR "MKR combat complex, which began to carry out combat duty to protect and defend our homeland. According to other data, on December 31, 1959 the first missile system with R-7A ICBMs was put on combat duty (part of Colonel G. Mikheev). Before launch, the missile was delivered from a technical position on the railway transport and installation on a massive launcher. The whole process of prelaunch preparation lasted more than two hours. The missile complex was cumbersome, vulnerable and very expensive and difficult to operate. Besides, the rocket could stay in the filled up state no more than 30 days. For creation and replenishment of necessary oxygen stock for deployed missiles the whole plant was needed. The complex had low operational readiness (readiness for launch was not less than 7 hours). Firing accuracy was also insufficient. The missile of this type was not suitable for mass deployment. In total, four launch facilities were built at the Angara facility (pad #41 Lesobaza, pad #16, pad #43 (2nd complex)). Another two were available at the Tyura-Tam range (Gagarin Launch site 1, site 31), but only one of the two (site 31) could be used for full-fledged combat duty of ICBMs. All five launch complexes were adopted for service by July 1961. According to available data, in the early 1960s the R-7A ICBMs equipped with a lightweight, reduced-capacity warhead were conducted (maximum range reached 12,000 km), but this modification was not put into mass production.

At the same time, despite all the shortcomings of the R-7 / R-7A, the mere presence of these missiles in service, albeit in small numbers, was an unambiguous signal to supporters of aggression against the USSR - it became clear that the deserved retribution in the event of war can not escape. Moreover, the development of these missiles testified to the fact that the USSR had an appropriate scientific and technological, industrial and personnel base, on the basis of which more advanced models of missiles of various classes would be developed in the near future, which was demonstrated.

Conceived and operated as a combat rocket, R-7 had a reliable and successful design, had the energy capabilities to launch into space (into Earth orbit) payloads of a significant mass. Therefore, after successful launches 8K71 as a ballistic missile, it was used in 1957 to launch the world's first artificial satellites. Since then, the R-7 family of launch vehicles has been actively used to launch various types of spacecraft, and since 1961, these launch vehicles have also been widely used in manned space. The reliability and success of the design made it possible to create on its basis a whole family of launch vehicles. It is difficult to overestimate the contribution of the "seven", but even more difficult to imagine the gift of foresight S.P. Korolev, who laid the foundation for many decades of domestic astronautics. In total, since 1957 by the middle of 2010, more than 1800 rockets based on the R-7 design were launched, of which more than 97% were successfully. On the basis of the already proven Soyuz-U and Soyuz-U2 LVs, a significantly improved Soyuz-2 LV has been developed that will be used not only from the traditional launch pads - Baikonur and Plesetsk ranges - but also from the European Space Agency's Kourou launch site (French Guiana, South America). R-7-based missiles will be used for many more years and only the family of promising Angara boosters being created by the Russian manufacturers' cooperation to replace Soyuz and Proton boosters will be able to squeeze them out a bit, but the beginning of the "generation change" is unlikely to be expected before the end of the second half of the 2010s.

In the West, 8K71 (R-7) missile was designated SS-6 mod.1 Sapwood, while 8K74 (R-7A) was designated SS-6 mod.2 Sapwood.