At the end of the forties, the question of delivering new nuclear warheads to targets arose before Soviet designers. Bombers and ballistic missiles were considered as promising carriers of atomic weapons. However, the development of aviation and missile technology at that time did not allow pinning great hopes on it. Existing and promising ballistic missiles had insufficient flight range to defeat targets in the United States, and aircraft to perform a combat mission had to break through enemy air defenses. It was necessary to find a way to solve the problem.
Preliminary work
In the early fifties, supersonic bombers and cruise missiles (projectile aircraft according to the classification of those years) were considered as a promising means of delivering nuclear warheads. Such a technique could attack targets, overcoming enemy air defenses. However, the achievement of high flight data required to break through the defense was associated with a host of technical and technological problems. Nevertheless, the way for the development of delivery vehicles has been determined. In the Soviet Union, several projects were launched to create promising aviation and rocket technology.
Back in the late forties, several research organizations proved the fundamental possibility of creating an intercontinental cruise missile (ICR) with a cruising speed of at least 3000 km / h and a range of about 6000 kilometers. Such ammunition could destroy targets on enemy territory with the help of a nuclear warhead, and was also capable of overcoming all existing air defense systems. However, the construction of an intercontinental cruise missile required the creation of new technologies and new special equipment.
The first project of a domestic MCR was developed at OKB-1 under the leadership of S. P. Queen. One of the most important tasks in the course of this project was the creation of navigation and control systems. Without such equipment, a promising cruise missile could not reach the target area, and there was no question of its reliable defeat. The new MCR was supposed to use the astronavigation system and navigate by the stars. The development of the astronavigation system turned out to be a difficult task - this equipment had to not only accurately determine the coordinates of the rocket, tracking the stars, but also work in conditions of numerous interference (the sun, other stars, glare from clouds, etc.). In 1953, employees of NII-88 under the leadership of I. M. Lisovich completed work on the AN-2Sh astronavigation system. In the future, this system was improved, but no fundamental changes were made to its design.
The MKR project, created at OKB-1, determined the main features of the appearance of all future missiles of this class. Korolev suggested using a two-stage scheme. This means that the intercontinental cruise missile had to take off vertically using a liquid-propellant first stage. After climbing to the required height, the second-stage ramjet sustainer was to be switched on. The second stage was actually a projectile plane. The theoretical study of this proposal showed its prospects, as a result of which all new MCR projects implied the use of a two-stage architecture.
Project "Tempest" / "350"
The design bureau under the leadership of Korolev worked on a new ICR until 1954, after which it was forced to abandon this project, since all his forces were spent on the R-7 intercontinental ballistic missile (ICBM) project. In the spring of the 54th, all work on the subject of MCR was transferred to the jurisdiction of the Ministry of Aviation Industry.
On May 20, 1954, the Council of Ministers issued a decree requiring the development of two versions of intercontinental cruise missiles. OKB-301, headed by S. A. Lavochkin and OKB-23 V. M. Myasishchev. The projects received the code names "Tempest" (OKB-301) and "Buran" (OKB-23). In addition, the projects bore the factory designations "350" and "40", respectively. Academician M. V. Keldysh.
The design team of OKB-301, when creating the Tempest / 350 project, had to look for new non-trivial solutions to emerging technical problems. The requirements for a promising MCR were such that the creation of a product that satisfies them was associated with the creation and development of new technologies. Looking ahead, it should be noted that during the Tempest project, Soviet industry mastered the manufacture and processing of titanium parts, created several new heat-resistant alloys and materials, and also developed a large number of special equipment. In the future, all these technologies were repeatedly used in new projects. An interesting fact is that the chief designer of the "titanium" cruise missile "The Tempest" was N. S. Chernyakov, who later went to the P. O. Sukhoi and supervised the creation of the "titanium" missile carrier T-4.
The preliminary design of the Tempest MKR took only a few months. Already in August 1954, OKB-301 submitted the project documentation to the customer. Product "350" was to be built according to the same scheme as the MKR, previously developed under the leadership of S. P. Queen. It was proposed to make the "Tempest" two-stage, and the second stage was supposed to be a projectile aircraft with a ramjet engine, an autonomous control system and a nuclear warhead.
The customer considered the proposed project, however, expressed some new wishes and adjusted the technical requirements. In particular, the weight of the warhead was increased by 250 kg, up to 2.35 tons. Because of this, the designers of the design bureau S. A. Lavochkin had to make significant adjustments to the "350" project. The intercontinental cruise missile retained the general features of its appearance, but it became noticeably heavier and increased in size. Because of this, the starting weight of the two-stage system increased to 95 tons, 33 of which were in the second stage.
In accordance with the updated project, several models were built, which were tested at TsAGI and LII. At the Flight Research Institute, the aerodynamics of the models were tested by dropping from a converted carrier aircraft. All preliminary tests and design work were completed at the beginning of 1957. By this time, the project had acquired its final appearance, which in the future remained almost unchanged. Soon after the end of the project, construction of several prototypes began.
Technical features
Built according to the scheme proposed at the beginning of the decade, the Tempest MCR consisted of a first (booster) stage with liquid-propellant rocket engines and a second (sustainer) stage, which was a projectile aircraft and equipped with a nuclear warhead. As noted by the aviation historian N. Yakubovich, the design of the "Tempest" can be described both from the standpoint of rocketry and from the point of view of aviation. In the first case, the "Tempest" looks like a two- or three-stage (if we take into account a detachable warhead) rocket system, in the second - like a vertical take-off projectile with rocket boosters.
The first stage of the "Tempest" MCR consisted of two blocks. Each of them had fuel tanks for 6300 kg of fuel and 20840 kg of oxidizer. In the tail section of the blocks were placed four-chamber engines S2.1100, developed at OKB-2 under the leadership of A. M. Isaeva. In the gas jet of the engines, rudders were located, designed to correct the flight trajectory at the first stage of the flight. The first stage of the intercontinental cruise missile was intended to lift the cruise missile to a height of about 17,500 meters. After that, the automation was supposed to turn on the second-stage ramjet engine and reset the upper stages.
The second stage of the product "350" was actually a cruise missile. The fuselage of the second stage was almost completely given over to the supersonic ramjet engine RD-012, developed under the leadership of M. M. Bondaryuk. Fuel tanks were located between the skin and the air intake channel in the fuselage. On the upper surface of the fuselage, in its middle and tail sections, there was a compartment with guidance equipment and a cooling system. The warhead was located in the central body of the adjustable air intake. The second stage of the "Tempest" was made according to the aerodynamic design of the midwing and had a delta wing of low aspect ratio. The sweep along the leading edge is 70 °. In the tail of the rocket, an X-shaped tail with rudders was provided.
Despite the estimated maximum flight range of at least 7000-7500 kilometers, MKR "350" turned out to be quite compact. The total length of the rocket ready for launch was approximately 19, 9 meters. The first and second stages were slightly shorter. The launch boosters were 18.9 meters long and no more than 1.5 meters in diameter. Each of the blocks of the first stage at the start provided a thrust of the order of 68.6 tf. The 18-meter second stage had a fuselage with a diameter of 2.2 meters and a wing span of 7.75 meters. Its ramjet engine at cruising speed provided thrust up to 7, 65 tf. The total mass of the MCR ready for launch exceeded 97 tons, 33, 5 of which accounted for each of the blocks of the first stage and 34.6 tons for the second stage. It should be noted that in the course of modifications and tests, the starting weight of the Tempest rocket has repeatedly changed, both up and down.
To launch the Tempest rocket, a special launch complex was created on a railway platform. After withdrawal to the launch position, the launch complex was supposed to be deployed in the desired direction and to raise the rocket to a vertical position. On command, the rocket with the help of the first stage engines was supposed to rise to a height of about 17, 5 kilometers. At this height, the spent blocks of the first stage were uncoupled and the second-stage ramjet engine was started. With the help of a ramjet engine, the second stage was supposed to accelerate to a speed of the order of M = 3, 1-3, 2. On the cruising section, the astronavigation system was switched on, which corrected the flight trajectory. A few tens of kilometers from the target, the "Tempest" was supposed to rise to an altitude of 25 km and go into a dive. During the dive, it was proposed to drop the central body of the air intake with the warhead. Tests of mock-ups dropped from the carrier aircraft showed that the deflection of the missile warhead at the maximum range will not exceed 10 kilometers from the target.
Testing
By the middle of 1957, several copies of the "350" product were made. In July, they were taken to the Kapustin Yar test site (according to some sources, the tests were carried out at the Vladimirovka test site). The first launch of the Tempest rocket was scheduled for July 31, 1957 (according to other sources, for August 1). During the first test launch, it was supposed to check the operation of the first stage. However, due to the failure of the systems, the launch did not take place and the rocket was sent for revision. In the first few tests, instead of the finished second stage, its mass and size mock-up was used. It was a rocket body with fuel tanks filled with sand or water. The first flight of the promising MCR took place only on September 1 and ended in failure. A few seconds after the start, an emergency shooting of gas rudders occurred, due to which the product lost control and fell near the starting position. The last launch of the 57th year, which took place on October 30, also ended in an accident.
After a number of improvements, tests resumed on March 21, 1958. The purpose of the fourth launch was to test the flight at the initial stage of the trajectory. Instead of the planned 95 seconds, the 350 rocket stayed in the air for just over one minute. At the 60th second of the flight, the control automatics, for some reason, turned the rocket into a dive, and after 3 seconds the product crashed into the ground. On April 28, the next "Bure" managed to make a flight lasting more than 80 seconds. This time, the reason for the premature fall of the rocket was a failure in the operation of the electrical systems, due to which the first stage units were dropped. The rocket climbed to a high-rise about 15 kilometers.
The launch on May 22, 1958 was the first successful one during the test program. The product "350" lightened by 30%, in 90 seconds of operation of the first stage engines, rose to an altitude of more than 17 kilometers and reached a speed of about M = 2.95. At this speed, the second stage ramjet engine was started normally. The test rocket fell in a given area two minutes after launch. Test launches in order to practice the flight at the initial stage of the trajectory and tests of the second stage continued until the end of March 1959. Of the seven launches carried out from June 11, 1958 to March 29, 59th, only one was recognized as successful. In two, various systems failed at the start, the rest ended in in-flight accidents.
It should be noted that the successful flight on March 29, 1959 was not entirely successful. The first stage successfully brought the MCR to the design height, after which the supersonic ramjet engine began to work. The flight of the second stage of the product "350" with half fuel filling took place at an altitude of 15 kilometers. In 25 minutes 20 seconds, the rocket covered more than 1300 kilometers. However, during level flight, due to a malfunction of the onboard equipment, the speed decreased slightly.
From April 19, 1959 to February 20, 60, three more launches were carried out, which were recognized as successful. During the April flight, the Tempest MKR stayed in the air for more than 33 minutes and covered over 1,760 kilometers. Some sources claim that during these tests, the rocket flew about 2,000 km, then turned in the opposite direction and flew another 2,000 km.
In mid-1959, OKB-301 updated the project by equipping the Tempest intercontinental cruise missile with new engines. The first stage was now equipped with C2.1150 engines, and the second one received a power plant of the RD-012U type. New types of engines provided an increase in thrust and, as a consequence, in flight performance. The first flight of the modernized MKR took place on October 2, 1959. On the marching section of the trajectory, the rocket used the astronavigation system for the first time. On February 20 of the following year, the Tempest rocket set a new range record, having flown about 5500 kilometers.
Of the four test launches in 1960, only one ended in an accident. On March 6, 25-26 minutes after the start, malfunctions began in the operation of the sustainer ramjet engine. The flight was interrupted, giving the command to self-destruct. By this time, the rocket had flown about 1,500 kilometers.
According to the test flight program on March 23, 1960, MKR "Tempest" was supposed to reach Cape Ozerny (Kamchatka). The launch, the ascent to an altitude of 18 km and the subsequent flight on the marching section took place without any problems. It took no more than 12-15 seconds to turn on and start the operation of the astronavigation system. On the 118th minute of the flight, the second stage tanks ran out of fuel. After another 2-2, 5 minutes, the rocket was supposed to go into a dive, but the control system failed. The stable flight of the rocket "350" lasted 124 minutes, after which it fell, covering a total of over 6500 kilometers. The speed on the marching section reached M = 3, 2.
On December 16 of the same year, the Tempest rocket was supposed to reach the Kura test site (Kamchatka). The product flew over 6400 kilometers and deviated from the calculated trajectory by no more than 5-7 kilometers. The speed of the second stage reached M = 3, 2. All systems operated normally during this flight. The flight was terminated after running out of fuel.
Projects based on the "Tempest"
Already in 1957-58, after several successful tests of the R-7 intercontinental ballistic missile, it became clear that the "350" project in the form of a strike system had practically no prospects. Intercontinental cruise missiles were inferior to ballistic missiles in flight time and, as a consequence, in combat capabilities. In addition, the MCR, in contrast to the warheads of ICBMs, in the future could become a fairly easy target for promising air defense systems. Because of this, on February 5, 1960, the Council of Ministers decided to stop work on the Tempest intercontinental cruise missile project. By the same resolution, OKB-301 was allowed to conduct five additional test launches, designed to test various systems.
This permission was due to the fact that back in 1958, the designers under the leadership of S. A. Lavochkin and N. S. Chernyakov began to work on a promising unmanned reconnaissance aircraft based on the "Buri". In July 1960, the country's leadership demanded to develop a strategic complex of photo and radio-technical reconnaissance, using the existing developments on the MKR "350". The scout was supposed to fly at altitudes of about 25 km at a speed of 3500-4000 km / h. The range was set at 4000-4500 kilometers. The unmanned reconnaissance aircraft had to be equipped with several PAFA-K and AFA-41 aerial cameras, as well as the Rhomb-K electronic reconnaissance complex. It was proposed to create two versions of an unmanned aerial vehicle. One of them was supposed to receive landing devices that ensured its reusable use. The second option was supposed to be disposable. To do this, he had to carry a supply of fuel necessary for flying at a distance of up to 12,000-14,000 kilometers, as well as radio equipment for transmitting data at a distance of up to 9 thousand km.
On June 9, 1960, S. A. Lavochkin. The project of a promising strategic intelligence officer was literally orphaned. Due to the lack of support from the general designer, the project slowed down, and by the end of the year it was closed. It should be noted that not only Lavochkin's death affected the fate of the project. By this time, there was a real opportunity to create a reconnaissance satellite with a suitable set of equipment. The operation of such systems was slightly more difficult than using a modified cruise missile. In addition, to launch reconnaissance satellites, it was proposed to use carrier rockets unified with R-7 ICBMs. Because of this, the project of a strategic photographic and radio-technical reconnaissance was closed.
During the development of the reconnaissance aircraft, only three of the five permitted test launches were carried out. Another one, held on December 16, 1960, had different goals. At the beginning of the 60th, OKB-301 employees suggested using MKR "350" as the basis for a high-speed high-altitude target, which could be used to prepare calculations for the Dal anti-aircraft missile systems. After a single test run under the target development program, the project was discontinued. The Dal SAM project itself was also not successful - it was closed in 1963.
Outcomes
In December 1960, all work on the reconnaissance and targets stopped. Such revisions of the "Tempest" project were considered unpromising. Thus, the "350" project did not give any results in the form of a practically applicable shock, reconnaissance, etc. systems. Nevertheless, this project cannot be considered unsuccessful. When developing intercontinental cruise missiles, Soviet scientists and designers carried out a large amount of research, created a lot of new technologies and developed several important directions. Especially for promising MCRs, the country's first astronavigation system and a number of other radio-electronic equipment were created. Also, it should be noted the development of several new technologies associated with the manufacture and processing of titanium parts. An important part of the Tempest project was the development of a supersonic ramjet engine. The development of the RD-012 engine allowed accumulating a large amount of knowledge in this area, which was used in later projects.
As for the immediate results of the project, the Tempest, as well as the entire class of intercontinental cruise missiles, simply could not withstand the competition with intercontinental ballistic missiles that appeared in the late fifties. Ballistic missiles, such as the R-7, had a greater modernization potential and higher combat capabilities. The Soviet Union of the fifties and sixties could not afford to simultaneously conduct several projects of strategic strike systems and therefore was forced to take into account their prospects. Intercontinental ballistic missiles turned out to be more profitable and more convenient than cruise missiles in a number of parameters. It should be noted that such savings previously led to the termination of work on the Buran MKR project, which was being developed at OKB-23 under the leadership of V. M. Myasishchev. The country's leadership and the command of the armed forces considered it unprofitable to simultaneously create two cruise missiles with approximately equal characteristics.
As a result, the Tempest intercontinental cruise missile became the next item in a long list of weapons and military equipment that made it possible to create new equipment or master new technologies, but did not enter service. In recent years, leading countries have again shown their attention to high-speed long-range cruise missiles. Perhaps, in the future, new projects will lead to the creation of MCR, in some way similar to the "Tempest". However, such a scenario cannot be ruled out, in which new projects will repeat the fate of the Soviet product "350".
