Before the advent of intercontinental ballistic missiles, long-range bombers were the primary means of delivering nuclear weapons. In addition, several other delivery vehicles have been proposed. So, until a certain time, the leading countries of the world worked on projects of strategic cruise missiles capable of carrying nuclear warheads and flying at a distance of several thousand kilometers. The emergence of new ICBMs led to the curtailment of such projects, but one of these cruise missiles not only passed tests, but was also put into service. For a short time, the US military operated the Northrop SM-62 Snark missile.
The American program for the development of strategic cruise missiles was launched in the mid-forties. Having studied domestic and foreign missile technology projects, the command of the US Air Force in August 1945 issued technical requirements for promising weapons. It was required to develop a cruise missile with a flight speed of about 600 miles per hour (about 960 km / h) and a range of 5000 miles (8000 km) with the ability to carry a warhead weighing 2 thousand pounds (about 900 kg). For the next several months, the industry was engaged in a preliminary study of a project for such a weapon.
In January 1946, Northrop Aircraft presented a preliminary design for a new cruise missile with different characteristics. The available technologies made it possible to build a rocket with a subsonic speed and a range of about 3000 miles (4800 km). Soon, the military demanded to redo the project in accordance with the new requirements. Now it was necessary to develop two variants of cruise missiles with different characteristics. One was supposed to have a subsonic speed and range of 1,500 miles (2,400 km), the other had to be made supersonic with a range of up to 5,000 miles. The payload of both missiles was set at 5000 pounds (about 2300 kg).
Serial rocket SM-62 Snark in the museum. Photo Rbase.new-factoria.ru
In accordance with the new order of the military, the company "Northrop" began work on two new projects. The subsonic missile was named the MX-775A Snark, the supersonic - MX-775B Boojum. Also in the early stages of the Snark project, the alternative designation SSM-A-3 was used. The titles of the projects, "Snark" and "Boojum," were taken from Lewis Carroll's "Snark Hunt". According to this poem, the snark was a mysterious creature living on a distant island. Bujum, in turn, was a particularly dangerous type of snark. It is unknown why John Northrop chose these names for the two new projects. Nevertheless, the names justified themselves: the development of the "Snark" was no less difficult than the hunt for its literary namesake.
Preliminary work on two projects continued until the end of 1946, after which problems began. At the very end of the 46th, the military department decided to cut costs, including by closing some new projects. The updated defense budget included the closure of the MX-775A Snark project, but allowed the development of the MX-775B Boojum to continue. J. Northrop did not agree with this decision, which is why he was forced to start negotiations with the command of the military aviation. In the course of lengthy negotiations, he managed to defend the Snark project, although this required a change in the technical proposal. Now it was proposed to increase the range of the MX-775A missile to 5 thousand kilometers.miles, and the cost of an individual rocket (with a series of 5 thousand units) was reduced to 80 thousand dollars. It was planned to complete the development of the project in two and a half years. According to the calculations of J. Northrop, more than half of the required effort should have been applied to the development of guidance systems.
The head of the aircraft manufacturer managed to defend the MX-775A project. In early 1947, the military decided to resume its development. At the same time, the previous decision regarding the MX-775B project was revised. The Bujum missile project, due to its great complexity, was transferred to the category of long-term research. These works yielded results much later, and already within the framework of the next project.
One of the early prototypes of the MX-775A in flight. Photo Designation-systems.net
Work on the Snark project continued, but the development of this rocket was associated with a lot of difficulties. To fulfill the requirements, the designers had to carry out a lot of new research and solve a large number of specific problems. In addition, the project faced misunderstanding or even opposition from some military leaders. In theory, an intercontinental cruise missile could indeed take off from US soil and deliver a nuclear warhead to a potential enemy's territory. However, the very first stages of the project clearly showed how difficult it is to create such a weapon, and how expensive it will be. In addition, the conservatism of the command affected, which relied more on the usual bombers. It is worth noting that critics of the MX-775A and MX-775B projects were right in some issues, which was later confirmed in practice.
The misunderstanding of some commanders in the future led to a change in plans several times. So, in 1947, a schedule was approved, according to which 10 test launches of a new rocket were to be carried out. The first launch was scheduled for the spring of 1949. Due to the complexity of the project, the development company did not have time to start testing on time, which led to the activation of opponents of the project. Pointing to the missed deadline, in 1950 they were able to push through a project cut. This time, the arguments about a dubious concept with ambiguous prospects were supplemented by facts of missed deadlines. Nevertheless, this time, J. Northrop and some representatives of the command were able to save the "Snark" project and continue its development.
In the meantime, the military has already drawn up a proposed methodology for the use of as yet non-existent weapons. It was planned that the MX-775A Snark cruise missiles would be used as a first strike weapon to ensure the further operation of the strategic nuclear forces. The target of the "Snarks" was to be radar stations and other air defense facilities of the Soviet Union. Thus, the first attack of cruise missiles was planned to "knock out" the air defense, after which strategic bombers with nuclear bombs on board had to enter into action. It was they who were supposed to destroy the main objects of command, industry and troops.
The first flight of a promising cruise missile did not take place in 1949, as required by the schedule. Nevertheless, by this time, Northrop Grumman had already begun assembling the first prototype, which was to be tested in the near future. Interestingly, the prototype of the rocket had to be noticeably different from the finished serial product. So, the first checks were supposed to be carried out using missiles of the N-25 project. In the future, on their basis, it was planned to create a new full-fledged combat missile.
General layout of the Snark missiles. Figure Alternalhistory.com
The N-25 missile was a typical projectile designed to engage ground targets. She received a cylindrical fuselage with ogival nose and tail fairing, swept wing and tail, consisting only of a large keel. The total length of this product was 15.8 m, the wingspan was 13.1 m. The takeoff weight was determined at 12.7 tons. The Allison J33 turbojet engine was chosen as the power plant. It was placed in the aft fuselage, next to the control equipment. The middle part of the rocket was given for fuel tanks, and a weight simulator of the warhead was placed in the bow.
The prototype N-25 was supposed to be used to test the flight characteristics of the rocket, which affected some of its features. It was equipped with radio command control: it was supposed to control the missile from an aircraft equipped with the necessary equipment. In addition, the experimental rocket was equipped with a retractable ski landing gear and a braking parachute for landing after test flights. It was supposed to take off from a special launcher.
Initially, the first flight of the MX-775A rocket was planned for 1949, but these dates were disrupted. Due to the complexity of the project and constant problems, the first prototypes of the N-25 were built only in 1950, and the first successful flight took place in April 51, two years after the originally indicated deadline. Tests of a radio-controlled aircraft-projectile at the Holloman base (New Mexico) showed the fundamental possibility of implementing the existing plans, and also made it possible to test the airframe and power plant.
For testing, 16 N-25 products were built. Until March 1952, 21 test flights were performed. During these checks, radio-controlled missiles developed a speed of up to M = 0.9 and remained in the air for up to 2 hours 46 minutes. Most of the tests ended in failure, which is why only five of the 16 built missiles survived until the spring of 52. One of the reasons for the numerous failures was the specific aerodynamics of the rocket, due to which the products flew with a large pitch angle, literally lifting their nose.
Rocket launch. Photo Wikimedia Commons
Further use of the N-25 product or its use as a basis for combat work was not possible. Back in the middle of 1950, the Air Force updated the requirements for a promising rocket, which required a serious revision of the project. The military demanded to increase the weight of the payload to 3200 kg, to provide the possibility of a short-term supersonic throw to break through the enemy's air defense, and also to improve the guidance accuracy. The KVO at the maximum range should not have exceeded 500 m.
To comply with the updated requirements, it was necessary to begin the development of a new project, which received the corporate designation N-69A Super Snark. This rocket as a whole was based on existing developments, but differed from the N-25 in its large size, new engine and other units. The streamlined fuselage, which contained all the necessary equipment, was preserved, and the high-positioned swept wing was again used. The tail unit without a stabilizer has also been preserved. Roll and pitch control was now carried out using controlled wing planes.
The airframe design turned out to be quite successful and met all the requirements. With some modifications of certain units, it was later used in new modifications of the "Super-Snark". The total length of the rocket was 20, 5 m, the wingspan was reduced to 12, 9 m. The starting mass of the N-69A product was set at 22, 2 tons.
Due to the increase in size and weight of the structure, a new engine was needed. The updated rocket was equipped with an Allison J71 turbojet engine. Its task was to accelerate the rocket to speeds of the order of 800-900 km / h with the possibility of a short "jerk" at supersonic speed. For the initial acceleration during takeoff, it was proposed to use two solid-propellant boosters.
Takeoff. The operation of the starting accelerators is clearly visible. Photo Rbase.new-factoria.ru
The proposal for the use of accelerators has led to the need for additional testing. In mid-1952, Northrop Aircraft built three weight models of the N-69A missile, which were used in drop tests. In November of the same year, tests of the second version of the accelerator began. Until the spring of the 53rd, four launches of modified N-25 missiles were performed, in which two boosters with a thrust of 47 thousand pounds (about 21, 3 tons) were used. Based on the test results for use with a combat missile, paired boosters with a thrust of 130 thousand pounds (59 tons) each were selected, operating for 4 s. This was enough to lift the rocket and preliminary acceleration before turning on the main engine.
By the time the drop tests began, the MX-775A project again faced administrative problems. The command demanded that the tests be transferred from the Holloman base to the Patrick airbase (Florida). The construction of new facilities required for missile verification took a long time, which over the next few years, tests were carried out at the old site.
By the mid-fifties, Northrop specialists developed a new version of the Super Snark project, which differed from the basic composition of the equipment and some other features. This version of the rocket received the working designation N-69B. In 1954-55, several new test launches were carried out. Constant checks and improvements made it possible to improve the design, but it was not possible to completely eliminate all the shortcomings. Nevertheless, already in 1955, the "Snark" project was brought to full-fledged tests with the attack of training targets. However, even in this case, not all launches were successful.
In May 1955, an event occurred that later led to the emergence of a new modification of the rocket. Another experimental missile successfully flew to the target area, but could not hit it, falling at a considerable distance from it. In connection with this failure, a new proposal appeared concerning the method of using the combat load. Now it was required to make the warhead detachable. Leaving the target area, the rocket had to drop a nuclear warhead, after which it had to fall on the target along a ballistic trajectory. The remaining units of the rocket should have been undermined, creating a mass of false targets that made it difficult to intercept the warhead. This method of using weapons, according to calculations, made it possible to drop a warhead from a distance of about 80 km from the target.
Warhead separation in flight. Photo Wikimedia Commons
An updated project with the designation N-69C was developed by the fall of 1955. On September 26, the first launch of such a rocket took place. In November, another new modification was created - the N-69D. It was a modified version of the "C" rocket, powered by a Pratt & Whitney J57 engine. The use of such an engine made it possible to reduce fuel consumption, due to which the calculated flight range reached the required values. In addition, the N-69D rocket had to carry drop outboard fuel tanks.
At the same time, the most important innovation of the "D" project was the astro-inertial guidance system, which allowed the rocket to independently reach the target. The development of such systems started back in the late forties, but the first experiments using astroinertial navigation in flying laboratories were carried out only in the early fifties. By the middle of the decade, a system was created suitable for installation on a cruise missile.
In theory, inertial navigation with astrocorrection made it possible to increase the accuracy of following the indicated course, but in practice everything was much more complicated. Problems with the power plant or airframe were almost resolved, but there were problems with guidance systems, which again led to accidents. Perhaps the most famous and interesting unsuccessful launch of the N-69D rocket took place in December 1956. The rocket took off from the Florida base and headed for the specified area of the Atlantic Ocean. During the flight, the testers lost contact with the launched rocket, which is why the tests were considered unsuccessful. The lost rocket was found only in 1982. Due to problems with the navigation system, she reached Brazilian airspace and fell into the jungle.
Scheme of the serial missile SM-62. Figure Lozga.livejournal.com
In June 1957, tests began on a new modification of the rocket, the N-69E. The cruise missiles of this version were actually pre-production products. By the time this version of the "Snark" appeared, the main design issues had been worked out, and most of the shortcomings had been eliminated. At the same time, however, far from all the shortcomings were corrected. There were a lot of problems, and besides, the characteristics of the finished product still left much to be desired. Due to the impossibility of fulfilling the initial requirements, the terms of reference for the MX-775A project were adjusted several times. The same thing happened before the creation of the N-69E rocket. The next version of the requirements differed from the first in a number of parameters. In particular, it was planned to further increase the flight range, but the accuracy requirements were again relaxed.
The strategic cruise missile of the last experimental modification had a length of 20.5 m and a wing span of 12.9 m. Takeoff weight was 21.85 tons, two launch boosters weighed another 5.65 tons. Raneta was equipped with a J57 turbojet engine with a thrust of 46.7 kN, which allowed her to reach speeds of up to 1050 km / h. The practical ceiling was set at 15.3 km, the maximum flight range reached 10200 km. The rocket received an astro-inertial navigation system, which made it possible to hit targets at a maximum range with a KVO of 2.4 km. A detachable warhead of the W39 type with a thermonuclear charge with a capacity of 3, 8 megatons was envisaged.
In parallel with the construction and testing of the N-69E missiles, the leadership of the Pentagon and industry tried to determine the future of a promising missile. It had a number of characteristic advantages over the existing means of delivering nuclear weapons, but at the same time it was not devoid of characteristic disadvantages. The Snark missile had a large flight range, which made it possible to perform the assigned tasks, and an acceptable hitting accuracy on the indicated target. In terms of speed, the rocket did not differ much from existing bombers. In addition, the supporters of the project pressed on the economic features of the project. Despite the complexity and high cost, the Snark rocket was about 20 times cheaper than the newest Boeing bombers.
Snark rocket in flight. Photo Wikimedia Commons
In 1958, the new missile was accepted into service under the designation SM-62. Over the next few years, it was planned to form several formations armed with such missiles. Nevertheless, numerous difficulties led to the fact that in the end only one missile wing was put on duty. The first serial missiles were handed over to the troops at the very beginning of 1958. They armed the 702nd Strategic Missile Wing (Presque Isle Base, Maine). Soon, the connection made several training launches.
The training missile launches, as in the case of the tests, were made towards the Atlantic Ocean. By no means all launches carried out by troop crews ended in successful defeat of training targets. In most cases, there was a failure of certain nodes, because of which the missiles fell into the ocean. The Atlantic coastal region near the base soon received the nickname Snark infested waters. However, there have been successful launches as well. For the first time, the military managed to hit a training target in April 1959.
Soon, attempts began to deploy SM-62 Snark missiles to other bases, but due to the complexity of the work required and the need to build various facilities, these work were not crowned with success. They simply did not have time to be completed until 1961, when the final decision was made on the further fate of the entire project.
Officially, SM-62 missiles have been in service since 1958. However, this was not a full-fledged service on alert. The development company continued to fine-tune the missiles, including by modifying the products already delivered. Simultaneously with this, new launch complexes, command posts and other facilities were being built. All these works were completed only by the end of 1960.
Serial rocket in the museum. Photo Fas.org
The 702nd wing was recognized as fully operational only in February 1961. By this time, 12 launchers were built on the basis of the compound, on which one missile was located in a state of constant readiness. In case of receiving an order, the personnel of the base had to carry out an immediate launch of all missiles aimed at objects of the Soviet Union. Due to the subsonic speed, the missile took several hours to fly to the target.
It should be recalled that from the very beginning of the work, the "Snark" project became the object of criticism from the military leaders and politicians. First of all, the reason for negative reviews was the dubious concept of a subsonic cruise missile with an intercontinental range and the low reliability of finished products. In the future, the list of topics of criticism was replenished with new points. In addition, by the early sixties, the SM-62 cruise missiles were being compared to the latest Titan ballistic missiles. At a similar cost, they were easier to operate, more reliable and more efficient. Also, the concept of an intercontinental ballistic missile made it possible to develop such weapons with a significant increase in basic characteristics.
In early 1961, John F. Kennedy became the new president of the United States. The Kennedy administration has decided to carry out several important reforms, including in the area of armaments. Another analysis of the Snark project showed an unacceptably low ratio of the cost and effectiveness of this development. The consequence of this was the order of the country's leadership to stop all work on the project and to remove the missiles from service. At the end of March 1961, J. Kennedy criticized the SM-62 missiles in his speech. In June of the same year, the Minister of Defense ordered the disbandment of the 702nd Strategic Missile Wing and the removal of existing cruise missiles from service. A full connection service lasted less than four months. Some of the missiles available in the troops were disposed of, some products were donated to several museums.
The MX-775A / N-25 / N-69 / SM-62 project was based on the controversial concept of a cruise missile with an intercontinental range. The project proposed the creation of a projectile aircraft capable of taking off from the United States and hitting a target on the territory of the Soviet Union. Solving such a problem with technology at the end of the fifties was extremely difficult, which led to the corresponding consequences. The designers of Northrop Aircraft were faced with a variety of problems, the solution of which took a serious investment of time, effort and money. As a result, the set design task, in general, was completed, but the reliability of the finished equipment left much to be desired.
Museum specimen. Photo Designation-systems.net
The efforts of engineers, J. Northrop and the military, who supported the project, made it possible to bring the SM-62 missile to service in the army, but all the shortcomings were not corrected, which affected its further fate. The change in the country's leadership, as well as the emergence of new weapons, put an end to the history of the Snark project. In addition, this ended all attempts to adapt surface-to-surface cruise missiles for use as strategic weapons. In the future, other original ideas were proposed, but the projects of "classical" strategic cruise missiles were not developed later.
It should be noted that the SM-62 project, despite an unsuccessful completion, led to the emergence of the only strategic intercontinental cruise missile, which managed to reach service in the army. In the fifties and sixties, several projects of such weapons were created in the world at once, but only the "Snark" product reached serial production and use in the troops. Other projects were closed at earlier stages, when the excessive complexity of creating such systems and the lack of real prospects in the light of the current development of rocket technology were revealed.
