Russian aviation at a glance. Soviet nuclear aircraft

It may seem strange that nuclear power, which is firmly rooted in the earth, in the hydrosphere, and even in space, has not taken root in the air. This is the case when apparent safety considerations (although not only them) outweighed the obvious technical and operational benefits from the introduction of nuclear power plants (NPS) in aviation.

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Meanwhile, the likelihood of severe consequences of incidents with such aircraft, provided they are perfect, can hardly be considered as higher in comparison with space systems using nuclear power plants (NPP). And for the sake of objectivity, it is worth recalling: the accident of the Soviet artificial earth satellite Kosmos-954 of the US-A type, which occurred in 1978 with the fall of its fragments into the territory of Canada, which occurred in 1978, did not lead to the curtailment of the maritime space reconnaissance and target designation system. (MKRTs) "Legend", the element of which was the US-A (17F16-K) devices.

On the other hand, the operating conditions of an aviation nuclear power plant designed to create thrust by generating heat in a nuclear reactor supplied to the air in a gas turbine engine are completely different from those of satellite nuclear power plants, which are thermoelectric generators. Today, two schematic diagrams of an aviation nuclear control system have been proposed - open and closed. The open-type scheme provides for the heating of air compressed by the compressor directly in the reactor channels with its subsequent outflow through the jet nozzle, and the closed type provides for heating the air using a heat exchanger, in a closed loop of which the coolant circulates. The closed circuit can be one- or two-circuit, and from the point of view of ensuring operational safety, the second option looks the most preferable, since the reactor block with the first circuit can be placed in a protective shockproof shell, the tightness of which prevents catastrophic consequences in case of aircraft accidents.

In closed-type aviation nuclear systems, pressurized water reactors and fast neutron reactors can be used. When implementing a two-circuit scheme with a "fast" reactor in the first circuit of the NPS, both liquid alkali metals (sodium, lithium) and an inert gas (helium) would be used as a coolant, and in the second, alkali metals (liquid sodium, eutectic sodium melt, etc.) potassium).

Reactor in the air

The idea of using nuclear energy in aviation was put forward in 1942 by one of the leaders of the Manhattan Project, Enrico Fermi. She became interested in the command of the US Air Force, and in 1946 the Americans embarked on the NEPA (Nuclear Energy for the Propulsion of Aircraft) project, designed to determine the possibilities of creating an unlimited-range bomber and reconnaissance aircraft.

"The idea of giving the naval aviation an anti-submarine aircraft with an unlimited flight range in the Kremlin was to the liking"

First of all, it was necessary to conduct research related to the anti-radiation protection of the crew and ground service personnel, and to give a probabilistic-situational assessment of possible accidents. In order to speed up the work, the NEPA project in 1951 was expanded by the US Air Force to the target program ANP (Aircraft Nuclear Propulsion). Within its framework, General Electric was developing an open circuit, and Pratt-Whitney was developing a closed NPS circuit.

For testing the future aviation nuclear reactor (exclusively in the mode of physical launches) and biological protection, the serial B-36H Peacemaker strategic bomber of the Convair company was intended with six piston and four turbojet engines. It was not a nuclear aircraft, but was just a flying laboratory where the reactor was to be tested, but it received the designation NB-36H - Nuclear Bomber ("Atomic bomber"). The cockpit was transformed into a lead and rubber capsule with an additional steel and lead shield. To protect against neutron radiation, special panels filled with water were inserted into the fuselage.

The prototype aircraft reactor ARE (Aircraft Reactor Experiment), created in 1954 by the Oak Ridge National Laboratory, became the world's first homogeneous nuclear reactor with a capacity of 2.5 MW on fuel from a molten salt of sodium fluoride and zirconium and uranium tetrafluorides.

The advantage of this type of reactors lies in the fundamental impossibility of an accident with the destruction of the core, and the fuel salt mixture itself, in the case of a closed-type aviation nuclear power plant, would act as a primary coolant. When a molten salt is used as a coolant, the higher, in comparison, for example, with liquid sodium, the heat capacity of the molten salt makes it possible to use circulating pumps of small dimensions and to benefit from a decrease in the metal consumption of the structure of the reactor plant as a whole, and the low thermal conductivity was supposed to ensure the stability of the nuclear aircraft engine against sudden temperature jumps. in the first circuit.

On the basis of the ARE reactor, the Americans have developed an experimental aviation YSU HTRE (Heat Transfer Reactor Experiment). Without further ado, General Dynamics designed the X-39 aircraft nuclear engine based on the serial J47 turbojet engine for the strategic bombers B-36 and B-47 “Stratojet” - instead of a combustion chamber, the reactor core was placed in it.

Konvair intended to supply the X-39 with the X-6 - perhaps its prototype would have been the B-58 supersonic strategic bomber Hustler, which made its maiden flight in 1956. In addition, the atomic version of an experienced subsonic bomber of the same YB-60 company was also considered. However, the Americans abandoned the open-circuit aviation NSU, considering: the erosion of the walls of the air channels of the X-39 reactor core will lead to the fact that the aircraft will leave a radioactive trail, polluting the environment.

The hope for success was promised by the more radiation-safe closed-type nuclear power plant of the Pratt-Whitney company, to the creation of which General Dynamics was also involved. For these engines, the company "Convair" began the construction of experimental aircraft NX-2. Both turbojet and turboprop versions of nuclear bombers with nuclear power plants of this type were being worked out.

However, the adoption in 1959 of the Atlas intercontinental ballistic missiles, capable of striking targets in the USSR from the continental United States, neutralized the ANP program, especially since production samples of atomic aircraft would hardly have appeared before 1970. As a result, in March 1961, all work in this area in the United States was stopped by the personal decision of President John F. Kennedy, and a real atomic plane was never built.

The flight sample of the aircraft reactor ASTR (Aircraft Shield Test Reactor - a reactor for testing the aircraft protection system), located in the bomb compartment of the NB-36H flying laboratory, was in no way connected with the engines of a 1 MW fast neutron reactor operating on uranium dioxide and cooled by a stream of air taken through special air intakes. From September 1955 to March 1957, the NB-36H made 47 flights with ASTR over uninhabited areas of the states of New Mexico and Texas, after which the car was never lifted into the sky.

It should be noted that the US Air Force also dealt with the problem of a nuclear engine for cruise missiles or, as it was customary to say until the 60s, for projectile aircraft. As part of the Pluto project, Livermore Laboratory created two samples of the Tory nuclear ramjet engine, which was planned to be installed on the SLAM supersonic cruise missile. The principle of "atomic heating" of air by passing through the reactor core here was the same as in open-type nuclear gas turbine engines, with only one difference: the ramjet engine lacks a compressor and a turbine. Tories, successfully tested on the ground in 1961-1964, are the first and so far the only really operating aviation (more precisely, missile and aviation) nuclear power plants. But this project was also closed as hopeless against the background of successes in the creation of ballistic missiles.

Catch up and overtake!

Of course, the idea of using nuclear energy in aviation, independently of the Americans, also developed in the USSR. Actually, in the West, not without reason, they suspected that such work was being carried out in the Soviet Union, but with the first disclosure of the fact about them they got into a mess. On December 1, 1958, Aviation Week reported: The USSR is creating a strategic bomber with nuclear engines, which caused considerable excitement in America and even contributed to maintaining the interest in the ANP program, which had already begun to fade away. However, in the drawings accompanying the article, the editorial artist quite accurately depicted the M-50 aircraft of the experimental design bureau of V.M. Myasishchev, which was actually being developed at that time, with a completely "futuristic" appearance, which had conventional turbojet engines. It is not known, by the way, whether this publication was followed by a "showdown" in the KGB of the USSR: work on the M-50 took place in an atmosphere of the strictest secrecy, the bomber made its first flight later than the mention in the Western press, in October 1959, and the car was presented to the general public only in July 1961 at the air parade in Tushino.

As for the Soviet press, for the first time about the atomic plane was told in the most general terms by the magazine "Technics - Youth" back in No. 8 for 1955: “Atomic energy is increasingly used in industry, energy, agriculture and medicine. But the time is not far off when it will be used in aviation. Gigantic machines will easily take off from airfields. Nuclear planes will be able to fly almost as long as you like, without sinking to the ground for months, making dozens of non-stop round-the-world flights at supersonic speed. " The magazine, hinting at the military purpose of the machine (civil aircraft do not need to be in the sky "as long as you like"), nevertheless presented a hypothetical diagram of a cargo-passenger airliner with an open-type nuclear power plant.

However, the Myasishchevsky collective, and not the only one, really dealt with aircraft with nuclear power plants. Although Soviet physicists have been studying the possibility of their creation since the end of the 40s, practical work in this direction in the Soviet Union started much later than in the United States, and they began with the decree of the Council of Ministers of the USSR No. 1561-868 of August 12, 1955. According to him, OKB-23 V.M. Myasishchev and OKB-156 A.N. Tupolev, as well as aircraft-engine OKB-165 A.M. Lyulka and OKB-276 N.D. Kuznetsov were tasked with developing atomic strategic bombers.

The aircraft nuclear reactor was designed under the supervision of Academicians I. V. Kurchatov and A. P. Aleksandrov. The goal was the same as that of the Americans: to get a car that, having taken off from the territory of the country, would be able to strike targets anywhere in the world (first of all, of course, in the USA).

A feature of the Soviet atomic aviation program was that it continued even when the topic was already forgotten in the United States.

When creating a nuclear power plant, we thoroughly analyzed the open and closed circuit diagrams. So, under the open-type scheme, which received the code "B", the Lyulka Design Bureau developed two types of atomic-turbojet engines - axial, with the passage of the turbocompressor shaft through an annular reactor, and "rocker arms" - with a shaft outside the reactor, located in a curved flow path. In turn, the Kuznetsov Design Bureau worked on the engines according to the closed "A" scheme.

The Myasishchev Design Bureau immediately set about solving the most, apparently, difficult task - to design atomic super-high-speed heavy bombers. Even today, looking at the diagrams of future machines made in the late 50s, one can definitely see the features of the technical aesthetics of the XXI century! These are the projects of aircraft "60", "60M" (atomic seaplane), "62" for Lyulkovsk engines of the "B" scheme, as well as "30" - already for engines of Kuznetsov. The expected characteristics of the "30" bomber are impressive: maximum speed - 3600 km / h, cruising speed - 3000 km / h.

However, it never came to the detailed design of the Myasishchev nuclear aircraft due to the liquidation of OKB-23 in an independent capacity and its introduction into the rocket and space OKB-52 of V.N. Chelomey.

At the first stage of participation in the program, the Tupolev team was to create a flying laboratory similar in purpose to the American NB-36H with a reactor on board. Received the designation Tu-95LAL, it was built on the basis of the serial turboprop heavy strategic bomber Tu-95M. Our reactor, like the American one, was not mated with the engines of the carrier aircraft. The fundamental difference between the Soviet aircraft reactor and the American one was that it was water-cooled, with a much lower power (100 kW).

The domestic reactor was cooled by the water of the primary circuit, which in turn gave heat to the water of the secondary circuit, which was cooled by the flow of air running through the air intake. This is how the schematic diagram of the Kuznetsov NK-14A atomic turboprop engine was worked out.

The Tu-95LAL flying nuclear laboratory in 1961-1962 lifted the reactor into the air 36 times both in the operating and in the "cold" state in order to study the effectiveness of the biological protection system and the effect of radiation on the aircraft systems. According to the test results, the chairman of the State Committee for Aviation Technology P. V. Dementyev, however, noted in his note to the country's leadership in February 1962: with YSU was developed in OKB-301 S. A. Lavochkin. - K. Ch.), since the research work carried out is insufficient for the development of prototypes of military equipment, this work must be continued. "

In development of the design reserve of OKB-156, the Tupolev Design Bureau developed on the basis of the Tu-95 bomber a project of an experimental Tu-119 aircraft with NK-14A atomic turboprop engines. Since the task of creating an ultra-long-range bomber with the appearance in the USSR of intercontinental ballistic missiles and sea-based ballistic missiles (on submarines) has lost its critical relevance, the Tupolevites viewed the Tu-119 as a transitional model on the way to creating a nuclear anti-submarine aircraft based on the long-range passenger airliner Tu-114 , which also "grew" from the Tu-95. This goal was fully consistent with the concern of the Soviet leadership about the deployment by the Americans in the 1960s of a submarine nuclear missile system with Polaris ICBMs and then Poseidon.

However, the project of such an aircraft was not implemented. The plans to create a family of Tupolev supersonic bombers with nuclear control systems under the code name Tu-120 remained at the design stage, which, like the atomic air hunter for submarines, were planned to be tested in the 70s ...

Nevertheless, the Kremlin liked the idea of giving the naval aviation an anti-submarine aircraft with an unlimited flight range to combat NATO nuclear submarines in any region of the oceans. Moreover, this machine was supposed to carry as much ammunition as possible for anti-submarine weapons - missiles, torpedoes, depth charges (including nuclear) and sonar buoys. That is why the choice fell on the heavy military transport aircraft An-22 "Antey" with a carrying capacity of 60 tons - the world's largest wide-body turboprop airliner. The future aircraft An-22PLO was planned to be equipped with four atomic-turboprop engines NK-14A instead of the standard NK-12MA.

The program for the creation of such an unseen in any other fleet of a winged machine received the code name "Aist", and the reactor for the NK-14A was developed under the leadership of Academician A.P. Aleksandrov. In 1972, tests of the reactor began on board the An-22 flying laboratory (a total of 23 flights), and a conclusion was made about its safety in normal operation. And in the event of a serious accident, it was envisaged to separate the reactor unit and the primary circuit from the falling aircraft with a soft landing by parachute.

In general, the aviation reactor "Aist" has become the most perfect achievement of nuclear science and technology in its field of application.

If we consider that on the basis of the An-22 aircraft it was also planned to create an An-22R intercontinental strategic aviation missile system with an R-27 submarine ballistic missile, it is clear what a powerful potential such a carrier could receive if it was transferred to “atomic thrust” »With NK-14A engines! And although things did not come to the implementation of both the An-22PLO project and the An-22R project, it must be stated that our country has nevertheless overtaken the United States in the field of creating an aviation nuclear power plant.

There is no doubt that this experience, despite its exoticism, can still be useful, but at a higher quality level of implementation.

The development of unmanned ultra-long-range reconnaissance and strike aircraft systems may well follow the path of using nuclear systems on them - such assumptions are already being made abroad.

Scientists also predicted that by the end of this century, millions of passengers are likely to be transported by nuclear-powered passenger aircraft. In addition to the obvious economic benefits associated with replacing aviation kerosene with nuclear fuel, we are talking about a sharp decrease in the contribution of aviation, which, with the transition to nuclear power plants, will cease to “enrich” the atmosphere with carbon dioxide, to the global greenhouse effect.

In the author's opinion, aviation nuclear systems would perfectly fit into the commercial aviation and transport complexes of the future based on super-heavy cargo aircraft: for example, the same giant “air ferry” M-90 with a carrying capacity of 400 tons, proposed by the designers of the experimental machine-building plant named after V. M. Myasishchev.

Of course, there are problems in terms of changing public opinion in favor of nuclear civil aviation. There are also serious issues to be resolved related to ensuring its nuclear and anti-terrorist security (by the way, experts mention the domestic solution with parachute “shooting” of the reactor in case of an emergency). But the road, beaten more than half a century ago, will be mastered by the walking one.

A nuclear aircraft is a flying vehicle, or, more simply, an aircraft on which a nuclear reactor is installed as an engine. In the middle of the twentieth century, in the era of the rapid development of the peaceful atom, along with the construction, work began on the design of nuclear aircraft in the USSR and the USA.

Requirements for atomic-powered aircraft in the USSR

The project of an aircraft with an atomic engine had to solve the following tasks, similar to those in the design of atomic cars and atomic tanks:

The presence of a light and compact nuclear reactor that can lift an aircraft into the air
Crew biological protection
Atomic aircraft flight safety
Nuclear-powered jet engine design

Work on the design of atomic aircraft in the USSR was carried out by several design bureaus - Tupolev, Myasishchev and Antonov. Even the profile level of the USE in mathematics in 2017 is not enough to compare with the minds of the developers of that time, although science has made a tremendous step forward.

The most famous project of the Soviet atomic aircraft was Tu-119 - the development of OKB-156 named after Tupolev. The Tu-119 aircraft was designed on the basis of the Tu-95M and was supposed to become a flying laboratory for testing engines with a nuclear reactor. Work on the Soviet atomic-powered Tu-119 was started back in 1955. In 1958, the ground stand was ready, as well as the Tu-95 LAL aircraft with a nuclear reactor in the cargo hold. The ground stand with a nuclear reactor has been used since 1959 at the Semipalatinsk test site. And Tu-95 LAL made 34 test flights in 1961. With a total weight of the aircraft of 110 tons, 39 of them were occupied by the nuclear reactor itself. In such tests, the indicators of the biological protection of the crew were checked, as well as the operation of the nuclear reactor under new conditions.

Myasishchev's design bureau developed a project for the M50 A atomic plane - a supersonic bomber with an atomic engine on board. For the purpose of biological protection, the pilots of the M50 A aircraft were planned to be placed in a closed lead capsule, which alone weighed 60 tons, and the flight was supposed to take place only by instruments. In the future, it was planned to install an autonomous unmanned control.

To use this nuclear aircraft, separate airfields would be needed, as a result, the project was stopped at the root. Then the Myasishchev Design Bureau proposed a new one - the M30 with a more complex design and increased crew protection. The reduced weight of the aircraft made it possible to increase the payload by 25 tons. The first flight was supposed to take place in 1966, but it was not realized either.

The Antonov Design Bureau in the late sixties - early seventies of the last century worked on the AN-22 PLO project - an ultra-long-range low-altitude anti-submarine defense aircraft. A feature of this atomic aircraft was the use of conventional fuel during takeoff and landing, the nuclear reactor provided only the flight itself, lasting up to two days, with a range of 27,500 kilometers.

M-60 strategic atomic bomber project

Let's start with the fact that in the 1950s. in the USSR, in contrast to the United States, the creation of an atomic bomber was perceived not only as desirable, even if very much, but as a vital task. This attitude was formed among the top leadership of the army and the military-industrial complex as a result of the realization of two circumstances. First, the enormous, overwhelming advantage of the United States in terms of the very possibility of atomic bombing of the territory of a potential adversary. Operating from dozens of air bases in Europe, in the Middle and Far East, US aircraft, even with a flight range of only 5-10 thousand km, could reach any point in the USSR and return. Soviet bombers were forced to work from airfields on their own territory, and for a similar raid on the United States they had to cover 15-20 thousand km. There were no planes with such a range in the USSR at all. The first Soviet strategic bombers M-4 and Tu-95 could "cover" only the very north of the United States and relatively small areas of both coasts. But even these machines in 1957 numbered only 22. And the number of American aircraft capable of striking the USSR had reached 1800 by that time! Moreover, these were first-class bombers carrying atomic weapons B-52, B-36, B-47, and a couple of years later they were joined by the supersonic B-58.

The Tupolev flying laboratory, built on the basis of the Tu-95 within the framework of the "119" project, was actually the only aircraft on which the idea of a nuclear power plant was somehow implemented in metal.

Secondly, the task of creating a jet bomber of the required flight range with a conventional power plant in the 1950s. seemed overwhelmingly difficult. Moreover, supersonic, the need for which was dictated by the rapid development of air defense systems. The flights of the M-50, the first supersonic strategic carrier in the USSR, showed that with a load of 3-5 tons, even with two air refueling, its range can barely reach 15,000 km. But how to refuel at supersonic speed, and besides, over the enemy's territory, no one could answer. The need for refueling significantly reduced the likelihood of completing a combat mission, and in addition, such a flight required a huge amount of fuel - more than 500 tons in total for refueling and refueling aircraft. That is, in just one sortie, a bomber regiment could consume more than 10 thousand tons of kerosene! Even the simple accumulation of such fuel reserves grew into a huge problem, not to mention safe storage and protection from possible air strikes.

At the same time, the country had a powerful research and production base for solving various problems of using nuclear energy. It took its origin from Laboratory No. 2 of the USSR Academy of Sciences, organized under the leadership of IV Kurchatov at the height of the Great Patriotic War - in April 1943. At first, the main task of nuclear scientists was to create a uranium bomb, but then an active search for other possibilities began using a new type of energy. In March 1947 - only a year later than in the USA - in the USSR, for the first time at the state level (at a meeting of the Scientific and Technical Council of the First Main Directorate under the Council of Ministers), the problem of using the heat of nuclear reactions in power plants was raised. The Council decided to start systematic research in this direction with the aim of developing a scientific basis for obtaining electricity by fission, as well as setting in motion ships, submarines and aircraft.

The future academician A.P. Aleksandrov became the scientific supervisor of the work. Several options for nuclear aircraft power plants were considered: open and closed cycle based on ramjet, turbojet and turboprop engines. Various types of reactors were developed: with air and with intermediate liquid metal cooling, with thermal and fast neutrons, etc. Coolants acceptable for use in aviation and methods of protecting the crew and onboard equipment from radiation exposure were investigated. In June 1952, Aleksandrov reported to Kurchatov: "... Our knowledge in the field of nuclear reactors allows us to raise the question of creating in the coming years atomic energy engines used for heavy aircraft ...".

However, it took another three years for the idea to make its way. During this time, the first M-4 and Tu-95 managed to rise into the sky, the first nuclear power plant in the world began to operate in the Moscow region, and the construction of the first Soviet nuclear submarine began. Our agents in the United States began to transmit information about the large-scale work being carried out there to create an atomic bomber. These data were perceived as confirmation of the prospects of a new type of energy for aviation. Finally, on August 12, 1955, the Council of Ministers of the USSR issued Decree No. 1561-868, which ordered a number of aviation enterprises to begin work on nuclear issues. In particular, OKB-156 of A.N. Tupolev, OKB-23 of V.M. Myasishchev and OKB-301 of S.A. Lavochkin were to be engaged in the design and construction of aircraft with nuclear power plants, and OKB-276 N.D. Kuznetsov and OKB-165 A.M. Lyulka - the development of such control systems.

The most technically simple task was given to OKB-301, headed by S.A. Lavochkin - to develop an experimental cruise missile "375" with a nuclear ramjet engine of the OKB-670 design of MM Bondaryuk. The place of a conventional combustion chamber in this engine was occupied by an open-cycle reactor - air flowed directly through the core. The design of the airframe of the missile was based on the development of an intercontinental cruise missile "350" with a conventional ramjet engine. Despite the relative simplicity, the theme "375" did not receive any significant development, and the death of S.A. Lavochkin in June 1960 put an end to these works.

Atomic turbojet engine of the "rocker" scheme

Atomic turbojet engine "coaxial" scheme

One of the possible layouts of Myasishchev's atomic seaplane

Atomic flying laboratory project
based on M-50

M-30 strategic atomic bomber project

The Myasishchev team, then engaged in the creation of the M-50, was ordered to carry out a preliminary design of a supersonic bomber "with special engines of the chief designer AM Lyulka." In the OKB, the theme received the index "60", Yu.N. Trufanova was appointed the lead designer for it. Since, in the most general terms, the solution to the problem was seen in the simple equipping of the M-50 with nuclear-powered engines, and operating in an open cycle (for reasons of simplicity), it was believed that the M-60 would become the first atomic aircraft in the USSR. However, by the middle of 1956 it became clear that the task posed could not be solved so easily. It turned out that the aircraft with the new SU has a number of specific features that aircraft designers had never encountered before. The novelty of the problems that arose was so great that no one in the Design Bureau, and indeed in the entire mighty Soviet aviation industry, even had a clue from which side to approach their solution.

The first problem was the protection of people from radioactive radiation. What should it be? How much should you weigh? How to ensure the normal functioning of the crew, enclosed in an impenetrable thick-walled capsule, incl. overview from workplaces and emergency leaving? The second problem is a sharp deterioration in the properties of familiar structural materials caused by powerful fluxes of radiation and heat emanating from the reactor. Hence the need to create new materials. The third is the need to develop a completely new technology for operating nuclear aircraft and the construction of corresponding air bases with numerous underground structures. After all, it turned out that after stopping the open-cycle engine, not a single person would be able to approach it for another 2-3 months! This means that there is a need for remote ground handling of the aircraft and engine. And, of course, safety issues - in the broadest sense, especially in the event of an accident of such an aircraft.

Awareness of these and many other problems of stone unturned did not leave the original idea to use the M-50 glider. The designers focused on finding a new layout that seemed solvable to the problems mentioned. At the same time, the main criterion for choosing the location of a nuclear power plant on an aircraft was recognized as its maximum distance from the crew. In accordance with this, a preliminary design of the M-60 was developed, on which four atomic turbojet engines were located in the tail section of the fuselage in pairs in "two floors", forming a single nuclear compartment. The aircraft had a midplane layout with a thin cantilever trapezoidal wing and the same horizontal tail, located at the top of the keel. Missile and bomb armament was planned to be placed on the internal sling. The length of the aircraft was to be about 66 m, the take-off weight was to exceed 250 tons, and the cruising flight speed was 3000 km / h at an altitude of 18,000-20,000 m.

The crew was supposed to be placed in a deaf capsule with powerful multilayer protection made of special materials. The radioactivity of the atmospheric air excluded the possibility of using it for pressurizing the cabin and breathing. For these purposes, it was necessary to use an oxygen-nitrogen mixture obtained in special gasifiers by evaporation of liquid gases on board. The lack of visual coverage was to be compensated for by periscopes, television and radar screens, as well as the installation of a fully automatic aircraft control system. The latter was supposed to provide all stages of the flight, including takeoff and landing, target exit, etc. This led logically to the idea of an unmanned strategic bomber. However, the Air Force insisted on the manned version as more reliable and flexible in use.

Ground test bench for the reactor

Nuclear turbojet engines for the M-60 were supposed to develop a take-off thrust of the order of 22,500 kgf. Design Bureau A.M. Lyulka developed them in two versions: "coaxial" scheme, in which the annular reactor was located behind a conventional combustion chamber, and a turbocharger shaft passed through it; and the "rocker arm" scheme - with a curved flow path and the removal of the reactor outside the shaft. The Myasishchevites tried to use both the one and the other type of engine, finding in each of them both advantages and disadvantages. But the main conclusion contained in the Conclusion to the preliminary M-60 project sounded like this: “... along with the great difficulties in creating the engine, equipment and airframe of the aircraft, completely new problems arise in ensuring ground operation and protecting the crew, population and terrain in the event of an emergency landing. These tasks ... have not yet been resolved. At the same time, it is the possibility of solving these problems that determines the feasibility of creating a manned aircraft with a nuclear engine. " Truly prophetic words!

To translate the solution of these problems into a practical plane, V.M. Myasishchev began developing a project for a flying laboratory based on the M-50, on which one atomic engine would be located in the nose of the fuselage. And in order to radically increase the survivability of nuclear aircraft bases in the event of a war, it was proposed to abandon the use of concrete runways altogether, and turn the atomic bomber into a supersonic (!) M-60M flying boat. This project was developed in parallel with the land version and retained significant continuity with it. Of course, in this case, the wing and air intakes of the engines were raised as much as possible above the water. The take-off and landing devices included a nasal hydro-ski, ventral retractable hydrofoils and pivoting lateral stability floats at the ends of the wing.

Placement of the reactor and radiation sensors on the Tu-95LAL

The designers faced very difficult problems, but the work was going on, and the impression was that all difficulties could be overcome in a time significantly shorter than increasing the flight range of conventional aircraft. In 1958, V.M. Myasishchev, on the instructions of the Presidium of the Central Committee of the CPSU, prepared a report "The state and possible prospects of strategic aviation", in which he unequivocally stated: "... In connection with the significant criticism of the M-52K and M-56K projects [bombers on conventional fuel , - ed.] By the Ministry of Defense, in the line of insufficient range of such systems, it seems to us useful to concentrate all work on strategic bombers on the creation of a supersonic bombing system with atomic engines, providing the necessary flight ranges for reconnaissance and for precision bombing by suspended projectile aircraft and mobile and stationary targets ".

Myasishchev had in mind, first of all, a new project of a strategic bomber-missile carrier with a closed-cycle nuclear power plant, which was designed by the ND Kuznetsov Design Bureau. He hoped to create this car in 7 years. In 1959, an aerodynamic "canard" configuration with a delta wing and a significant sweep front tail was chosen for it. Six nuclear turbojet engines were supposed to be located in the tail section of the aircraft and combined into one or two packages. The reactor was located in the fuselage. It was supposed to use a liquid metal as a coolant: lithium or sodium. The engines were also able to run on kerosene. The closed cycle of the control system made it possible to make the cockpit ventilated with atmospheric air and to significantly reduce the weight of the protection. With a takeoff weight of about 170 tons, the mass of the engines with heat exchangers was assumed to be 30 tons, the protection of the reactor and the cockpit was 38 tons, and the payload was 25 tons. The length of the aircraft was about 46 m with a wingspan of about 27 m.

The first flight of the M-30 was planned for 1966, but Myasishchev's OKB-23 did not even have time to start detailed design. By a government decree, OKB-23 Myasishchev was involved in the development of a multistage ballistic missile of the OKB-52 design by V.N. Chelomey, and in the fall of 1960 it was liquidated as an independent organization, making this OKB branch No. 1 and completely reorienting to rocket and space topics. Thus, the groundwork of OKB-23 on nuclear aircraft was not embodied in real designs.

Tu-95LAL. In the foreground is a container with a radiation sensor.

Unlike the team of V.M. Myasishchev, who was trying to create a supersonic strategic aircraft, A.N. Tupolev's OKB-156 was initially given a more realistic task - to develop a subsonic bomber. In practice, this task was exactly the same as the one facing the American designers - to equip an already existing machine with a reactor, in this case the Tu-95. However, the Tupolevites did not even have time to comprehend the work ahead, as in December 1955, through Soviet intelligence channels, reports began to come in about the conduct of test flights of the B-36 with a reactor on board in the United States. NN Ponomarev-Stepnoy, now an academician, and in those years still a young employee of the Kurchatov Institute, recalls: “... Once Merkin [one of Kurchatov's closest colleagues - author] called Kurchatov and said that he had information that that in America a plane with a reactor flew. He is now going to the theater, but by the end of the performance he should have information about the possibility of such a project. Merkin gathered us. It was a brainstorming session. We came to the conclusion that such an aircraft exists. He has a reactor on board, but he flies on conventional fuel. And in the air, there is a study of the very scattering of the radiation flux that worries us so much. Without such research, it is impossible to assemble protection on an atomic plane. Merkin went to the theater, where he told Kurchatov about our findings. After that, Kurchatov suggested that Tupolev conduct similar experiments ... ".

On March 28, 1956, the Resolution of the Council of Ministers of the USSR was issued, according to which the Tupolev Design Bureau began designing a flying nuclear laboratory (LAL) based on the serial Tu-95. The direct participants in these works V.M.Vul and D.A.Antonov talk about that time: “... leading nuclear scientists of the country A.P. Aleksandrov, A.I.Leypunsky, N.N. Ponomarev-Stepnoy, V.I.Merkin and others told us about the physical foundations of atomic processes, reactor design, protection requirements, materials , control system, etc. Very soon, these seminars began lively discussions: how to combine nuclear technology with aircraft requirements and restrictions. Here is one example of such discussions: the volume of a reactor facility was initially described by atomic scientists to us as the volume of a small house. But the layout designers of the OKB were able to greatly "squeeze" its dimensions, especially the protective structures, while fulfilling all the stated requirements for the level of protection for the LAL. At one of the seminars, A.N. Tupolev noticed that “... houses are not carried on airplanes” and showed our layout. Atomic engineers were surprised - they had met such a compact solution for the first time. After careful analysis, it was jointly adopted for the LAL on the Tu-95 ”.

Tu-95LAL. Reactor fairings and air intake

During these meetings, the main goals of LAL creation were formulated, incl. study of the effect of radiation on aircraft assemblies and systems, verification of the effectiveness of compact protection against radiation, experimental study of the reflection of gamma and neutron radiation from the air at different flight altitudes, mastering the operation of nuclear power plants. Compact defense has become one of the "know-how" of the Tupolev team. Unlike OKB-23, the projects of which provided for placing the crew in a capsule with spherical protection of constant thickness in all directions, the designers of OKB-156 decided to use protection of variable thickness. In this case, the maximum degree of protection was provided only from direct radiation from the reactor, i.e. from behind the pilots. At the same time, the side and front shielding of the cockpit should be minimized due to the need to absorb radiation reflected from the surrounding air. For an accurate assessment of the level of reflected radiation, in the main, and set up a flight experiment.

For a preliminary study and gaining experience with the reactor, it was envisaged to build a ground test stand, the design work for which was entrusted to the Tomilinsky branch of the OKB, headed by I.F. Nezval. The stand was created on the basis of the middle part of the Tu-95 fuselage, and the reactor was installed on a special platform with a lift, and, if necessary, it could be lowered. Radiation protection at the stand, and then at the LAL, was manufactured using materials that were completely new for aviation, for the production of which new technologies were required.

Tu-95LAL. Dismantling the reactor.

A serial strategic bomber Tu-95M No. 7800408 with four NK-12M turboprop engines with a capacity of 15,000 hp each was converted into a flying laboratory, designated Tu-95LAL. All weapons were removed from the aircraft. The crew and experimenters were in the front pressurized cabin, where a sensor was also located, which recorded the penetrating radiation. A protective shield made of a 5-cm lead plate and combined materials (polyethylene and ceresin) with a total thickness of about 20 cm was installed behind the cockpit. A second sensor was installed in the bomb bay, where the combat load was to be located in the future. Behind it, closer to the tail of the aircraft, was the reactor. The third sensor was located in the rear cab of the vehicle. Two more sensors were mounted under the wing consoles in non-removable metal fairings. All sensors were rotatable around a vertical axis for orientation in the desired direction.

The reactor itself was surrounded by a powerful protective shell, also consisting of lead and combined materials, and had no connection with the aircraft engines - it served only as a source of radiation. Distilled water was used in it as a neutron moderator and, at the same time, as a coolant. The heated water gave off heat in an intermediate heat exchanger, which was included in a closed primary water circulation loop. Through its metal walls, heat was transferred to the water of the secondary circuit, in which it was dissipated in a water-to-air radiator. The latter was blown in flight by a stream of air through a large air intake under the fuselage. The reactor slightly went beyond the contours of the aircraft fuselage and was covered with metal fairings at the top, bottom and sides. Since the all-round protection of the reactor was considered to be quite effective, it included windows that could be opened in flight for conducting experiments on reflected radiation. The windows made it possible to create beams of radiation in different directions. The control of their opening and closing was carried out from the control panel of the experimenters in the cockpit.

Project of a nuclear anti-submarine aircraft based on Tu-114

The construction of the Tu-95LAL and the provision of the necessary equipment took 1959-60. By the spring of 1961, “... the plane was at an airfield near Moscow,” continues NN Ponomarev-Stepnoy's story, “and Tupolev arrived with Minister Dementyev to look at it. Tupolev explained the radiation protection system: "... It is necessary that there is not the slightest gap, otherwise neutrons will come out through it." "So what?" - the minister did not understand. And then Tupolev explained in a simple way: "On a frosty day you will go out onto the airfield, and your fly will be unbuttoned - everything will freeze!" The minister laughed - they say, now everything is clear with neutrons ... ”.

From May to August 1961, 34 flights were performed on the Tu-95LAL. The plane was flown by test pilots M.M. Nyukhtikov, E.A. Goryunov, M.A. Zhila and others, engineer N.V. Lashkevich was the leader of the car. The head of the experiment, the atomic scientist N. Ponomarev-Stepnoy and the operator V. Mordashev, took part in the flight tests. The flights took place both with a "cold" reactor and with an operating one. Investigations of the radiation situation in the cockpit and outside were carried out by physicists V. Madeev and S. Korolev.

Tests of the Tu-95LAL showed a fairly high efficiency of the applied radiation protection system, but at the same time revealed its cumbersomeness, too heavy weight and the need for further improvement. And the main danger of a nuclear aircraft was recognized as the possibility of an accident and the contamination of large spaces with nuclear components.

The further fate of the Tu-95LAL aircraft is similar to the fate of many other aircraft in the Soviet Union - it was destroyed. After the completion of the tests, he stood for a long time at one of the airfields near Semipalatinsk, and in the early 1970s. was transferred to the training airfield of the Irkutsk Military Aviation Technical School. The head of the school, Major General S.G. Kalitsov, who had previously served for many years in long-range aviation, had a dream of creating a museum of long-range aviation. Naturally, the fuel elements have already been removed from the reactor core. During the Gorbachev period of strategic arms reduction, the aircraft was counted as a combat unit, dismantled and thrown into a landfill, from which it disappeared into scrap metal.

The program assumed that in the 1970s. development of a series of atomic supersonic heavy aircraft under the single designation “120” (Tu-120) will begin. It was assumed that all of them would be equipped with closed-cycle nuclear turbojet engines developed by the ND Kuznetsov Design Bureau. The first in this series was to be a long-range bomber, close in purpose to the Tu-22. The aircraft was carried out according to the normal aerodynamic configuration and was a high-wing aircraft with swept wings and empennage, bicycle landing gear, a reactor with two engines in the rear fuselage, at the maximum distance from the cockpit. The second project was a low-altitude strike aircraft with a low delta wing. The third was the project of a long-range strategic bomber with

And yet the Tupolev program, like Myasishchev's projects, was not destined to be embodied in real constructions. Let it be a few years later, but the government of the USSR closed it too. The reasons, by and large, were the same as in the United States. The main thing is that the atomic bomber turned out to be an overwhelmingly complex and expensive weapon system. The newly appeared intercontinental ballistic missiles solved the problem of total destruction of the enemy much cheaper, faster and, so to speak, more guaranteed. Yes, and the Soviet country did not have enough money - at that time there was an intensive deployment of ICBMs and a nuclear submarine fleet, which spent all the funds. The unresolved problems of the safe operation of nuclear aircraft also played a role. The political excitement also left the Soviet leadership: by that time, the Americans had already curtailed work in this area, and there was no one to catch up, and it was too expensive and dangerous to go ahead.

In general, we installed the reactor on the platform, rolled it into An-22 No. 01-07 and flew to Semipalatinsk in early September. Pilots V. Samovarov and S. Gorbik, the leading engineer for engines V. Vorotnikov, the head of the ground brigade A. Eskin and I, the leading designer for the special installation, participated in the program from the Antonov Design Bureau. BN Omelin, a representative of CIAM, was with us. The military, nuclear scientists from Obninsk, joined the test site, there were a total of 100 people. Colonel Gerasimov was in charge of the group. The test program was called "Stork", and we drew a small silhouette of this bird on the side of the reactor. There were no special external markings on the plane. All 23 flights under the "Aist" program went smoothly, there was only one emergency. Once An-22 took off for a three-hour flight, but landed right there. The reactor did not turn on. The reason turned out to be a poor-quality plug connector, in which the contact was broken all the time. Sorted it out, inserted a match into the SR - it all worked. So they flew with a match until the end of the program.

In parting, as usual in such cases, they had a small feast. It was a holiday of men who had done their job. We drank, talked with the military, physicists. We were glad that we were returning home to our families. But physicists grew more and more gloomy: most of them were left by their wives: 15-20 years of work in the field of nuclear research negatively affected their health. But they had other consolations: after our flights, five of them became doctors of science, and fifteen people became candidates. "

So, a new series of flight experiments with a reactor on board was completed successfully, and the necessary data were obtained for the design of a sufficiently effective and safe aviation nuclear control system. The Soviet Union nevertheless overtook the United States, coming close to creating a real atomic plane. This machine was radically different from the concepts of the 1950s. with open cycle reactors, the operation of which would be associated with enormous difficulties and causing colossal harm to the environment. Thanks to the new protection and the closed cycle, radiation contamination of the aircraft structure and the air was minimized, and in environmental terms, such a machine even had certain advantages over chemical-fueled aircraft. In any case, if everything is working properly, then the exhaust stream of an atomic engine contains nothing but clean heated air.

4. Combined turbojet-nuclear engine:

1 - electric starter; 2 - dampers; 3 - air duct of the direct-flow circuit; 4 - compressor;

5 - combustion chamber; 6 - atomic reactor vessel; 7 - fuel assembly.

But this is if ... In the event of a flight accident, the problems of environmental safety in the An-22PLO project were not sufficiently resolved. Firing coal rods into the core did end the chain reaction, but again, as long as the reactor was intact. But what if this happens as a result of hitting the ground, and the rods do not take the desired position? It seems that it was precisely the danger of such a development of events that prevented this project from being realized in metal.

However, Soviet designers and scientists continued to search for a solution to the problem. Moreover, in addition to the anti-submarine function, the nuclear aircraft has found a new application. It arose as a logical development of the trend of increasing the invulnerability of ICBM launchers as a result of giving them mobility. In the early 1980s. The United States developed a strategic MX system, in which missiles constantly moved between numerous shelters, depriving the enemy of even the theoretical possibility of destroying them with a pinpoint strike. In the USSR, intercontinental missiles were installed on an automobile chassis and railway platforms. The next logical step would be to place them on a plane that would patrol over its territory or over the ocean. Due to its mobility, it would be invulnerable to the enemy's missile attack. The main quality of such an aircraft was the longest possible stay in flight, which means that the nuclear control system suited it perfectly.

... The end of the Cold War and the collapse of the Soviet Union prevented the implementation of this project. The motive, quite often encountered in the history of Russian aviation, was repeated: as soon as everything was ready for solving the problem, the problem itself disappeared. But we, the survivors of the Chernobyl disaster, are not very upset about this. And only the question arises: how to relate to the colossal intellectual and material costs incurred by the USSR and the United States, trying for decades to create an atomic plane? After all, everything is in vain! .. Not really. Americans have an expression: "We are looking beyond the horizon." So they say when they do work, knowing that they themselves will never use its results, that these results may be useful only in the distant future. Maybe someday mankind will once again set itself the task of building a nuclear powered aircraft. Maybe it won't even be a combat aircraft, but a cargo or, say, a scientific aircraft. And then future designers will be able to rely on the results of the work of our contemporaries. Who just looked beyond the horizon ...

M-60 strategic atomic bomber project
Let's start with the fact that in the 1950s. in the USSR, in contrast to the United States, the creation of an atomic bomber was perceived not only as desirable, even if very much, but as a vital task. This attitude was formed among the top leadership of the army and the military-industrial complex as a result of the realization of two circumstances. First, the enormous, overwhelming advantage of the United States in terms of the very possibility of atomic bombing of the territory of a potential adversary. Operating from dozens of air bases in Europe, in the Middle and Far East, US aircraft, even with a flight range of only 5-10 thousand km, could reach any point in the USSR and return. Soviet bombers were forced to work from airfields on their own territory, and for a similar raid on the United States they had to cover 15-20 thousand km. There were no planes with such a range in the USSR at all. The first Soviet strategic bombers M-4 and Tu-95 could "cover" only the very north of the United States and relatively small areas of both coasts. But even these machines in 1957 numbered only 22. And the number of American aircraft capable of striking the USSR had reached 1800 by that time! Moreover, these were first-class bombers carrying atomic weapons B-52, B-36, B-47, and a couple of years later they were joined by the supersonic B-58.

Nevertheless, the closure of the nuclear issue in the Tupolev Design Bureau did not at all mean the abandonment of the nuclear power plant as such. The military-political leadership of the USSR refused only from using the atomic plane as a means of delivering weapons of mass destruction directly to the target. This task was entrusted to ballistic missiles, incl. submarine-based. Submarines could covertly stay on duty for months off the coast of America and at any moment inflict a lightning strike from close range. Naturally, the Americans began to take measures aimed at combating Soviet missile submarines, and specially created attack submarines turned out to be the best means of such a fight. In response, Soviet strategists decided to organize a hunt for these secretive and mobile ships, and even in areas remote thousands of miles from their native shores. It was recognized that a sufficiently large anti-submarine aircraft with an unlimited flight range, which only a nuclear reactor could provide, could cope most effectively with such a task. to Semipalatinsk. Pilots V. Samovarov and S. Gorbik, the leading engineer for engines V. Vorotnikov, the head of the ground brigade A. Eskin and I, the leading designer for the special installation, participated in the program from the Antonov Design Bureau. BN Omelin, a representative of CIAM, was with us. The military, nuclear scientists from Obninsk, joined the test site, there were a total of 100 people. Colonel Gerasimov was in charge of the group. The test program was called "Stork", and we drew a small silhouette of this bird on the side of the reactor. There were no special external markings on the plane. All 23 flights under the "Aist" program went smoothly, there was only one emergency. Once An-22 took off for a three-hour flight, but landed right there. The reactor did not turn on. The reason turned out to be a poor-quality plug connector, in which the contact was broken all the time. Sorted it out, inserted a match into the SR - it all worked. So we flew with a match until the end of the program.

4. Combined turbojet-nuclear engine:

1 - electric starter; 2 - dampers; 3 - air duct of the direct-flow circuit; 4 - compressor;

5 - combustion chamber; 6 - atomic reactor vessel; 7 - fuel assembly.

It is not hard to guess that the idea of an aircraft with a nuclear power plant came into the minds of not only the American military and designers. In the Soviet Union, which was making the first steps in the development of atomic technologies, similar proposals appeared in the late 1940s. True, due to the general lag in the projects of nuclear warheads, the USSR did not seriously deal with this issue until a certain time. Nevertheless, over time, it became possible to allocate certain forces to create atomic-powered aircraft, besides, the country still needed such aircraft. Rather, the Soviet air force did not need nuclear-powered aircraft as a class of technology, but a new means of delivering nuclear weapons to the territory of a potential enemy.

The first Russian strategic bombers had insufficient range. So, after several years of work, the design team under the leadership of V.M. Myasishchev managed to increase the range of the 3M aircraft to 11-11.5 thousand kilometers. When using the in-flight refueling system, this indicator increased. However, the strategic bombers of that time had many problems. In light of the increased range, the greatest difficulty was ensuring timely refueling in the face of the risk of attack by enemy fighters. Later, due to the development of air defense systems, the problem of range became aggravated, and it was also necessary to start work on the creation of supersonic strategic aircraft.

By the end of the fifties, when these issues began to be considered, it became possible to conduct research on the topic of alternative power plants. Nuclear power plants have become one of the main options. In addition to providing a high flight range, including supersonic, they promised great financial savings. In the conditions of that time, the maximum range flight of one regiment of strategic bombers with jet engines could "eat" several thousand tons of kerosene. Thus, all the costs of building a complex nuclear power plant were fully justified. However, Soviet engineers, like American ones, faced a number of problems inherent in such power plants.

Start

The first documentary evidence of the existence of the Soviet atomic bomb program dates back to 1952, when the director of the Institute of Physical Problems of the USSR Academy of Sciences, future academician A.P. Alexandrov sent I.V. Kurchatov a document that spoke about the fundamental possibility of creating a nuclear power plant for aircraft. The next three years were spent on a leisurely study of the theoretical aspects of the issue. Only in April 1955, the USSR Council of Ministers issued a decree according to which the design bureaus of A.N. Tupolev, S.A. Lavochkin and V.M. Myasishchev were to begin the development of a heavy aircraft with a nuclear power plant, and the design organizations of N.D. Kuznetsov and A.M. The cradle was instructed to create engines for them. At this stage, the Soviet program for the creation of aircraft with a nuclear power plant was divided into several projects that differed from each other in the type of the aircraft itself, the engine layout, etc.

Intercontinental cruise missile "Tempest" - "Burana" grandmother

For example, OKB-301 (chief designer S.A. Lavochkin) was commissioned to create the 375 intercontinental cruise missile. The basis for this was to be the Tempest rocket, also known as the 350. After a series of investigations, the shape of the new rocket "375" was determined. In fact, it was the same "Tempest", but instead of a ramjet engine powered by kerosene, it was proposed to install a small nuclear reactor on it. Passing through the channels inside the rocket, the outside air had to come into contact with the reactor core and heat up. This simultaneously protected the reactor from overheating and provided sufficient thrust. It was also planned to change the layout of the original design in the absence of the need for fuel tanks. The development of the rocket itself was relatively simple, but, as is often the case, the subcontractors let down. OKB-670 under the direction of M.M. Bondaryuk for a long time could not cope with the creation of a ramjet nuclear engine for the product "375". As a result, the new cruise missile was not even built in metal. Soon after the death of Lavochkin in 1960, the topic "375", together with the original "Tempest", was closed. By this time, the design of a nuclear engine had gotten off the ground, but it was still far from testing the finished sample.

The teams of V.M. Myasishchev and A.M. Cradle. They were supposed to make a strategic bomber with a nuclear power plant. The project of the aircraft with the index "60" or M-60 at first seemed simple. It was supposed to put nuclear turbojet engines on the M-50 bomber under development, which would not require additional time and effort. The M-60 was seriously considered a contender for the title of the first full-fledged atomic aircraft not only in the USSR, but also in the world. It was only a few months after the start of the project that it became clear that the construction of Product 60 had been postponed for at least several years. In the project, it was necessary to solve a lot of specific issues that previously simply did not arise before domestic aircraft manufacturers.

First of all, the questions were raised by the protection of the crew. Of course, it would be possible to seat the pilots in a monolithic metal capsule. However, in this case, it was necessary to somehow provide an acceptable view, as well as make some rescue systems. The second major problem of the M-60 project concerned the safety of ground personnel. According to preliminary calculations, after only one flight, such a bomber should have "fired" for a couple of months. Maintenance of such equipment required a new approach, for example, the creation of certain systems for remote work with units and assemblies. Finally, the aircraft "60" had to be made of new alloys: a structure built in accordance with the available technologies would have an insufficient resource due to radiation and thermal loads. The chosen type of engine gave additional complexity to the project: an open-circuit turbojet.

All the technical problems associated with the characteristic features as a result forced the designers to completely rethink their first ideas. The glider of the M-50 aircraft could not be used in conjunction with nuclear engines. This is how the updated look of the 60 project appeared. Now the atomolet looked like a midwing with a thin trapezoidal wing. A stabilizer of a similar shape was planned to be installed on the keel. In front of the fuselage, in front of the wing, air intakes with a semicircular cross-section were placed. They walked along the fuselage along its entire length, skirting the cargo compartment in the middle. Four open-cycle nuclear turbojet engines were placed in the very tail of the fuselage, collecting them in a 2x2 square package.

In the nose of the M-60, it was supposed to install a multi-layer capsule-cockpit. Maintaining the working pressure inside the cabin was carried out using a supply of liquefied air on board. The intake of atmospheric air was quickly abandoned due to the possibility of radioactive particles entering the plane. The capsule-cabin did not have any glazing to ensure the proper level of protection. The pilots were supposed to observe the situation through periscopes, telesystems, and also with the help of a radar station. To ensure takeoff and landing, it was planned to create a special automatic system. Interestingly, plans for an automatic control system almost led to a change in the status of the project. The idea was to make the M-60 completely unmanned. However, as a result of disputes, the military insisted on the creation of a manned aircraft. Simultaneously with the M-60, the project of the M-60M flying boat was created. Such an atomic plane did not need runways vulnerable to air strikes, and also slightly facilitated nuclear safety. The flying boat differed from the original aircraft "60" in the location of the air intakes and other ski-type landing gear.

Preliminary calculations showed that with a take-off weight of about 250 tons, the M-60 aircraft should have an engine thrust of 22-25 tons each. With such engines, a bomber at altitudes of about 20 kilometers could fly at a speed of about 3000 km / h. In the design bureau A.M. Cradle considered two main options for similar turbojet nuclear engines. The coaxial scheme implied the placement of a nuclear reactor in the place where a combustion chamber is located in conventional turbojet engines. In this case, the motor shaft passed directly through the reactor structure, including through the core. Also considered was the scheme of the engine, which received the code name "Rocker". In this version of the engine, the reactor was moved away from the compressor and turbine shaft. The air from the air intake through a curved pipe reached the reactor and in the same way got to the turbine. In terms of the safety of the engine units, the “rocker arm” scheme was more advantageous, but it was inferior to the coaxial engine in its simplicity of design. As for the radioactive hazard, in this aspect the schemes were almost the same. Designers of OKB-23 worked out two options for the layout of engines, taking into account their dimensions and design differences.

M-30

By the end of the development of the M-60 project, both the customer and the designers came to not very pleasant conclusions regarding the prospects for atomic-powered aircraft. Everyone recognized that, with their advantages, nuclear engines have a number of serious disadvantages, both constructive and radiation in nature. At the same time, the entire program rested precisely on the creation of nuclear engines. Despite the difficulties with the creation of engines, Myasishchev convinced the military of the need to further continue research and design work. At the same time, the new project involved the installation of closed-type nuclear engines.

The new aircraft was named M-30. By the end of the fifties, the designers had already decided on its appearance. It was a duck-type aircraft equipped with two keels. In the middle of the fuselage of the aircraft there was a cargo compartment and a reactor, and in the tail section - six nuclear turbojet engines of a closed cycle. The power plant for the M-30 was developed at the design bureau of N.D. Kuznetsov and implied the transfer of heat from the reactor to the air in the engine through the coolant. Lithium and sodium in the liquid state were considered as the latter. In addition, the design of closed-type nuclear turbojet engines made it possible to use conventional kerosene in them, which promised to simplify the operation of the aircraft. A characteristic feature of the new closed circuit engine is the absence of the need for a dense arrangement of engines. Thanks to the use of a pipeline with a coolant, the reactor could be reliably closed with insulating structures. Finally, the engine did not emit radioactive material into the atmosphere, which made it possible to simplify the ventilation system of the cockpit.

In general, the use of a closed-type engine proved to be more profitable compared to the previous version. First of all, the benefit had a weight "embodiment". Of the 170 tonnes of takeoff weight of the aircraft, 30 accounted for the engines and heat transfer system and 38 for the protection of the reactor and crew. At the same time, the payload of the M-30 was 25 tons. The calculated flight characteristics of the M-30 differed slightly from the data of the M-60. The first flight of the new nuclear-powered bomber was scheduled for 1966. However, a few years before that, all projects with the letter "M" were curtailed. First, OKB-23 was involved in work on a different topic, and later it was reorganized. According to some sources, the engineers of this organization did not even have time to deploy a full-fledged design of the M-30 bomber.

Tu-95LAL

Simultaneously with OKB-23, the designers of the Tupolev firm worked on their project. Their task was a little simpler: to modify the existing Tu-95 for use with a nuclear power plant. Until the end of the 55th year, engineers were working on various issues related to the design of the aircraft, a specific power plant, etc. Around the same time, Soviet intelligence officers working in the United States began to send in the first information regarding similar American projects. Soviet scientists became aware of the first flights of an American flying laboratory with a nuclear reactor on board. Moreover, the available information was far from complete. Therefore, our engineers had to brainstorm, according to the results of which they came to the conclusion about a simple "removal" of the reactor, without using it as a source of energy. As a matter of fact, it was so in reality. In addition, the purpose of the test flights, our scientists considered the measurement of various parameters directly or indirectly related to the effect of radiation on the structure of the aircraft and its crew. Shortly thereafter, Tupolev and Kurchatov agreed to conduct similar tests.

Tu-95 LAL, the photo shows a convex lantern above the reactor

The development of a flying laboratory based on the Tu-95 was carried out in an interesting way. Designers of OKB-156 and nuclear scientists regularly held seminars, during which the latter were the first to tell about all the nuances of nuclear power plants, about their protection and design features. Thus, aircraft engineers received all the necessary information, without which they could not have made an atomic plane. According to the recollections of the participants in those events, one of the most memorable moments was the discussion of the protection of reactors. As the atomic lobbyists said, a ready-made reactor with all protection systems is the size of a small house. The layout department of the design bureau became interested in this problem and soon developed a new reactor layout in which all the units were of acceptable size and at the same time provided the proper level of protection. With an annotation in the style of "they don't carry at home on airplanes," this scheme was demonstrated to physicists. The new version of the reactor layout was thoroughly tested, approved by nuclear scientists and adopted as the basis for a power plant for a new flying laboratory.

The main goal of the Tu-95LAL project (flying nuclear laboratory) was to check the level of protection of the on-board reactor and to work out all the design nuances associated with it. An interesting approach was taken already at the design stage. Unlike Myasishchev's team, the Tupolevites decided to protect the crew only from the most dangerous directions. The main elements of radiation protection were placed behind the cockpit, and the rest of the directions were covered with less serious packages of various materials. In addition, the idea of a compact protection of the reactor was further developed, which, with some changes, was included in the Tu-95LAL project. At the first flying laboratory, it was planned to test the applied ideas of protecting the units and crew, and use the data obtained for the further development of the project and, if necessary, design changes.

By 1958, the first test reactor was built for testing. He was placed in a dimensional simulator of the fuselage of the Tu-95 aircraft. Soon, the test bench, along with the reactor, was sent to the test site near Semipalatinsk, where in 1959 the work reached the test launch of the reactor. By the end of the year, it was brought to its design capacity, and the protection and control systems were also finalized. Simultaneously with the tests of the first reactor, the assembly of the second, intended for the flying laboratory, was underway, as well as the alteration of the serial bomber for use in the experiment.

Serial Tu-95M # 7800408, when converted into a flying laboratory, lost all weapons, including the equipment associated with it. Immediately behind the cockpit, a five-centimeter lead plate and a 15-centimeter thick package of polymer materials were installed. In the nose, tail and middle of the fuselage, as well as on the wings, sensors were installed to monitor the level of radiation. An experimental reactor was placed in the rear cargo compartment. Its protection to some extent resembled that used in the cockpit, but the reactor core was placed inside a round protective casing. Since the reactor was used only as a radiation source, it was necessary to equip it with a cooling system. Distilled water circulated in the immediate vicinity of the nuclear fuel and cooled it. Then the heat was transferred to the water of the secondary circuit, which dissipated the received energy using a radiator. The latter was blown by the oncoming stream. The outer casing of the reactor as a whole fit into the outlines of the fuselage of the former bomber, however, holes had to be cut through the top and sides in the skin and covered with fairings. In addition, a radiator intake was brought out to the lower surface of the fuselage.

For experimental purposes, the reactor containment vessel was equipped with several windows located in different parts of it. Opening and closing of one or another window occurred on command from the control panel in the cockpit. With the help of these windows it was possible to increase the radiation in a certain direction and measure the level of its reflection from the environment. All assembly work was completed by the beginning of 1961.

In May 1961, the Tu-95LAL first took to the air. Over the next three months, 34 flights were performed with a "cold" and operating reactor. All experiments and measurements have proven the fundamental possibility of placing a nuclear reactor on board an aircraft. At the same time, several problems of a constructive nature were discovered, which were planned to be corrected in the future. And yet the accident of such an atomic aircraft, despite all the means of protection, threatened with serious environmental consequences. Fortunately, all experimental flights of the Tu-95LAL went smoothly and without any problems.

Dismantling the reactor from the Tu-95 LAL aircraft

In August 61st, the reactor was removed from the flying laboratory, and the aircraft itself was parked at the airfield at the test site. Several years later, the Tu-95LAL without a reactor was transferred to Irkutsk, where it was later decommissioned and cut into scrap metal. According to some sources, the reason for cutting the plane was the bureaucratic affairs of the Perestroika era. During this period, the Tu-95LAL flying laboratory was allegedly considered a combat aircraft and treated in accordance with international agreements.

Projects "119" and "120"

According to the results of tests of the Tu-95LAL aircraft, nuclear scientists finalized the reactor for the aircraft, and the Tupolev design bureau began work on the creation of a new atomic aircraft. Unlike the previous experimental aircraft, the new one was proposed to be made on the basis of the passenger Tu-114 with a slightly larger fuselage. The Tu-119 was supposed to be equipped with two kerosene turboprop engines NK-12M and two NK-14A, created on their basis. The "fourteenth" engines, in addition to the standard combustion chamber, were equipped with a heat exchanger to operate in the mode of heating air from the reactor, in a closed circuit. The layout of the Tu-119 to a certain extent resembled the placement of the units on the Tu-95LAL, but this time the plane had pipelines for the coolant connecting the reactor and two engines.

The development of turboprop engines with heat exchangers to transfer heat from the reactors was slow due to constant delays and problems. As a result, the Tu-119 never received the new NK-14A engines. Plans to create two flying laboratories with two nuclear engines on each were not implemented. The failure with the first experimental aircraft "119" led to the disruption of further plans, which implied the construction of an aircraft with four NK-14A at once.

The closure of the Tu-119 project also buried all plans for the 120 project. This high-wing aircraft with a swept wing was supposed to be equipped with four engines and carry anti-submarine equipment and weapons in the fuselage. Such an anti-submarine aircraft, according to calculations, could patrol for two days. The range and duration of the flight was actually limited only by the capabilities of the crew. Also in the course of the "120" project, the possibilities of creating a strategic bomber like the Tu-95 or 3M, but with six engines and a supersonic strike aircraft with the possibility of low-altitude flight, were studied. Due to problems with the NK-14A engines, all these projects were closed.

Nuclear "Antey"

Despite the unsuccessful completion of Project 119, the military did not lose the desire to get an ultra-long-range anti-submarine aircraft with a large payload. In 1965, it was decided to take the An-22 Antey transport plane as a basis for it. Inside the wide fuselage of this aircraft, it was possible to place a reactor, a whole range of weapons, and operator workstations along with special equipment. The NK-14A was again proposed as engines for the AN-22PLO aircraft, work on which gradually began to move forward. According to calculations, the duration of the patrol of such an aircraft could reach 50 (fifty!) Hours. Takeoff and landing were carried out using kerosene, flight at cruising speed - on the heat generated by the reactor. It should be noted that 50 hours was only the recommended flight duration. In practice, such an anti-submarine aircraft could fly even more until the crew loses the ability to work effectively or until technical problems begin. 50 hours in this case was a kind of warranty period, during which the An-22PLO would not have any problems.

The employees of the design bureau O.K. Antonova wisely disposed of the internal volumes of the Antey's cargo compartment. Immediately behind the cockpit, a compartment was placed for the target equipment and its operators, behind it were provided for living quarters, then a compartment for a rescue boat was "inserted" in case of an emergency landing on the water, and a reactor with protection was placed in the rear of the cargo compartment. At the same time, there was almost no room for weapons. Mines and torpedoes were proposed to be placed in enlarged landing gear fairings. However, after preliminary work on the layout, a serious problem was revealed: the finished aircraft turned out to be too heavy. Nuclear engines NK-14A with a capacity of 8900 hp simply could not provide the required flight characteristics. This problem was solved by changing the design of the reactor shield. After the revision, its mass was significantly reduced, but the level of protection not only did not suffer, but even increased slightly. In 1970, An-22 No. 01-06 was equipped with a point radiation source with protection, made in accordance with the later versions of the An-22PLO project. During ten test flights, it turned out that the new version of protection fully justified itself, and not only in terms of weight.

A full-fledged reactor was created under the leadership of A.P. Alexandrova. Unlike previous designs, the new aircraft reactor was equipped with its own control systems, automatic protection, etc. To control the reaction, the new nuclear unit received an updated carbon rod control system. In case of an emergency, a special mechanism was provided that literally fired these rods into the reactor core. The nuclear power plant was mounted on aircraft No. 01-07.

The test program, codenamed "Stork", began in the same 1970 year. During the tests, 23 flights were carried out, almost all of them went without complaints. The only technical problem was related to the connector of one of the equipment blocks. Due to a loose contact during one of the flights, it was not possible to turn on the reactor. Small repairs "in the field" made it possible to continue full-fledged flights. After the 23rd flight, the tests of the An-22 with an operating nuclear reactor on board were recognized as successful, the prototype aircraft was parked and research and design work on the An-22PLO project continued. However, this time too, design flaws and the complexity of the nuclear power plant led to the closure of the project. The ultra-long-range anti-submarine aircraft turned out to be super-expensive and super-complicated. In the mid-seventies, the An-22PLO project was closed.

After the termination of work on the anti-submarine version of "Antey" for some time, other options for the use of atomic-powered aircraft were considered. For example, it was seriously proposed to make a loitering carrier of strategic missiles on the basis of the An-22 or a similar machine. Over time, there were also proposals for improving the level of security. The main thing was to equip the reactor with its own parachute-based rescue system. Thus, in the event of an accident or serious damage to the aircraft, its power plant could independently make a soft landing. The area of her landing was not in danger of contamination. However, these proposals were not further developed. Due to past failures, the main customer in the person of the Ministry of Defense has lost interest in atomic-powered aircraft. The seemingly limitless prospects of this class of technology did not resist the pressure of technical problems and, as a result, did not lead to the expected result. In recent years, from time to time there have been reports of new attempts to create aircraft with a nuclear power plant, but even half a century after the flights of the Tu-95LAL flying laboratory, not a single aircraft flew using the fission energy of uranium nuclei.

Based on materials from sites:
http://vfk1.narod.ru/
http://testpilot.ru/
http://airwar.ru/
http://nkj.ru/
http://laspace.ru/
http://airbase.ru/

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