Aircraft 3M: history of creation and development, technical characteristics

The 3M airplane is a Soviet strategic bomber, which served for about four decades. In the history of this aircraft there were many different events. In the end, he received an ambiguous reputation. Someone calls this plane an emergency model, and someone considers it a great achievement. Anyway, the 3M aircraft, whose history of creation became the subject of our conversation, deserves attention as the most serious project of Soviet aircraft designers.

Prerequisites for creating

In the late 1940s, when nuclear weapons appeared, there was a need for its transportation and mobile delivery to the right place. The military complex needed bombers, which, according to characteristics, could exceed the models produced at that time by a factor of 1.5-2. So the concept of a strategic bomber was formed. America began to develop such aircraft earlier. In 1946, immediately two American aircraft companies - Boeing and Konveur - engaged in the development of a strategic bomber. So, in 1952, the first flight was made by the B-52 and B-60 aircraft. Both models differed from their predecessors with high ceilings, as well as impressive speed and range.

Start of development

In the USSR, similar developments started with a significant delay. It all began with the fact that the designer V. Myasishchev, who worked as a professor at the MAI, offered the government the creation of a strategic bomber capable of flying up to 12,000 kilometers. As a result, having consulted with the experts, J. Stalin decided, under his responsibility, to instruct Myasishchev to develop the aircraft he proposed, but he set deadlines. The development was to be completed on May 24, 1951. The Council of Ministries of the USSR commissioned the construction of the plane reconstructed after the closure of the OKB-23 MAP. The main designer was Myasishchev. Soon the Air Force Chief Commander approved the tactical and technical requirements for the car. The maximum range should be no less than 12 thousand kilometers with a bomb load of 5 tons. The plane was supposed to fly at a speed of 900 km / h at an altitude of 9 kilometers.

The time allotted for the design and construction of the bomber for the "Project 25" (as it was called in the development process) required the design bureau to cooperate with a number of other industry organizations: other design bureaus, research institutes and factories.

First developments

The first sketches of the aircraft were made by L. Selyakov - he had the role of a designer, aerodynamics and hardness at the same time. V. Myasishchev of those times was engaged in the formation of units, divisions and brigades. The team was created in parallel with the bomber. In the short term, the draft of the project was prepared and approved. Along with this, the production technology was developed, because before the USSR did not produce such large and heavy aircraft. For the machine, new sizes of profiles and materials, as well as nomenclature, were needed.

The bomber should have good aerodynamic performance, develop a high speed and be as light as possible. Designers paid much attention to the shape of the wing. During the first six months of development in the wind tunnel, TsAGI tested many models, until the optimum was found. The created wing was relatively light, had flexible end parts and was carried out according to the caisson structure. It well resisted the influence of the flutter. In the root part of the wing there were motors, each of which had an air intake. With its help it was possible to exclude the mutual influence of the engines when operating in different modes. The nozzles were deployed in the horizontal and vertical planes by 4 degrees. This measure was necessary to divert the hot gas jet from the fuselage and tail unit.

Equipment

The bomber's power plant included four of the most powerful turbojet engines of the Mikulina design. Their thrust was 8700 kG. When designing the power plant, the stake was made for maximum reliability. Incidentally, according to the original design, the aircraft was to be equipped with three motors with a thrust of 13,000 kG. However, OKB Dobrynina did not manage to prepare in a short period of time the prototypes of these engines.

Separately it is worth noting the design chosen by the designers of the bomber chassis. To work out the dynamics of the movement of such a heavy aircraft along the runway, a special expert group was organized. Initially, several chassis schemes were considered: standard with three supports, multi-support and bicycle. In the course of testing, the chassis, constructed on a bicycle scheme with a front "tug" trolley and side racks located at the ends of the wings, showed itself best of all. The plane steadily drove along the runway and took off with the necessary run-time.

The head pair of wheels, mounted on the front trolley, was oriented in a small range of angles (+ 15 ⁰ ). When the pair turned, the direction of the trolley's movement changed, and after it the direction of the whole aircraft changed. In the "uplifting" mode, the front pair of wheels became uncontrollable. At the final stage of takeoff the nose of the plane rose, and the angle of attack increased. Participation of the pilot in takeoff was minimal. This scheme was tested on a flying laboratory "Tu-4", a three-bearing chassis of which was specially replaced with a bicycle. A model of a separate electrically operated trolley was also constructed. The experimental chassis samples underwent a full range of tests and confirmed their suitability for use on the bomber.

The bomb load of the aircraft was 24 tons, and the largest caliber of bombs - 9000 kg. Thanks to the radar sight of the RPB-4, aiming bombing was provided. The bomber had a pretty powerful weapon for defense. It included six automatic guns with a caliber of 23 mm. They were placed in pairs in three rotary installations in the upper, lower and tail sections of the fuselage. The crew, consisting of eight people, was housed in two hermetic cabins. The seats were catapulted through the hatches down.

Testing

By December 1952, an experimental bomber was built. And on January 20 next year the car was first lifted into the air. Flight was led by test pilot F. Opadchiy. Since that day, the factory tests of the sample have started at full speed. They lasted until April 15, 1954. The delay was due to the volume and complexity of the tests.

The maximum flight weight of the aircraft was 181.5 tons. Its speed at an altitude of 6700 meters was 947 kilometers per hour. The practical ceiling (maximum range) with a weight of 138 tons was 12,500 meters. Designers managed to place on board a huge amount of fuel tanks. In them was placed 132390 liters of fuel. However, the maximum refueling was limited to 123600 liters.

In 1954, a second prototype was connected to the tests, which had a nose, shortened by 1 m, an enlarged wing area and a number of other, less significant modifications. Engineers began to prepare for batch batch production. By this time, in honor of the designer Myasishchev, the car was called "Aircraft M". "3M" is the index that was assigned to the model later. And at first it was called M-4.

The tests were not going well. For most of the characteristics, the aircraft was fully consistent with the mission, but the main requirement - the maximum flight range with 5 tons of bombs on board - it could not satisfy. After a number of improvements, the bomber did take it into service. But the issue of insufficient flight range remained open.

Revisions

To solve the above problem, the bomber has been equipped with more powerful and yet economical RD-3M engines developed by P. Zubets. The bomber with a new power plant received the "3M" index. In fact, the engines were a modified version of the engine AM-3A. The maximum thrust was increased to 9500 kG. Moreover, the installation of the RD-3M had an emergency mode, which in the event of a single engine failure increases the power of the rest to 10,500kG. With such power equipment, the 3M was able to develop a speed of 930 km / h and fly without stopping for distances up to 8100 km.

At this search for opportunities to increase the range of flight is not over. The second pilot version was equipped with a refueling system developed at the Alekseev Design Bureau. Above the cockpit of the pilot appeared "barbell" for fuel. Well, the tanker was equipped with an additional tank, equipment for pumping and a winch.

While the 3M Myasischev plane was being created, work was underway to develop its high-altitude version, which received the working name 2M. On it designers intended to install just four turbojet engines VD-5 - on pylons, spaced under the wing. However, the design of the "skyscraper" was discontinued, since the 3M version was able to achieve its design characteristics.

Aircraft 3M: development

Despite the good performance, the model continued to develop. March 27, 1956 took the first flight by car 3M. The aircraft received new VD-7 engines, which had a thrust of 11,000 kGs. At the same time, they weighed less and spent less fuel. First, the aircraft was equipped with two new engines, and by 1957 all four. Thanks to the installation of the new configuration wings and the improvement of the horizontal tail characteristics, the aerodynamic qualities of the aircraft have increased significantly. In addition, the volume of fuel tanks was increased. This was achieved, among other things, thanks to the suspension tanks. Two of them were suspended in the bomb compartment (if the bomb load allowed it), and two more - under the wings, between the engines.

The 3M aircraft, whose characteristics we are discussing today, received a lightweight design. However, its weight still rose to 193 tons, and with suspension tanks and even more - up to 202 tons. Over time, the front of the fuselage acquired a new layout. There was an opportunity to move the antenna station from under the fuselage to the nose, which was lengthened by 1 meter. Thanks to the new navigation equipment, the 3M aircraft could carry out effective bombing from a great height at any time of the day and under any conditions.

As a result, all the improvements led to the fact that the maximum flight range, compared with previous versions, increased by 40%. With one refueling, suspension tanks and maximum bomb load, this figure exceeded 15,000 km. To conquer such a distance, the plane needed about 20 hours. Thus, there appeared the prospect of using it as an intercontinental strategic bomber. The 3M aircraft was exactly the machine that Myasishchev originally wanted to create, assuming great responsibility and enlisting the support of Stalin.

Another interesting quality of 3M is the fact that it can be used as a distant marine torpedo bomber. Torpedoes entered the staff of the armament, but they were used extremely rarely. The first tests of the sea version of the bomber were carried out on the prototype M-4.

Merits of the aircraft 3M

The airplane after the latest improvements was adopted for service and launched into mass production. In 1959 pilots N. Goryainov and B. Stepanov, together with their crews, installed 12 world records on it. Among them was a rise with a 10-ton cargo to a height of more than 15 kilometers and a rise with a 55-ton cargo to a height of 2 kilometers. In the tables of world records, the aircraft was named 201M. In the same year test pilot A. Lipko and his team set seven speed records on a closed route, with varying degrees of loading. With a cargo weight of 25 tons, he developed a speed of 1,028 km / h. In official documents, 3M Myasishchev's plane was again named in another - 103M.

When the new strategic bomber entered service, some of the previously released versions of the M-4, which differed only in a weak power plant, were refitted into tankers.

Problems in operation and a new motor

Despite the highest performance, the aircraft had a number of problems. The most important of them was that the overhaul life of the VD-7 engines was much lower than that of the RD-3M-500A engines. Therefore, for the purpose of carrying out routine maintenance work, the engines were often changed. While solving problems with VD-7, the planes were installed by those same RD-3M, from which the success of the model began. With this power plant, it was called 3MS. Of course, compared to the 3M aircraft showed the worst results, but it was much better than its prototype - the M-4 version. In particular, without refueling, the ZMS aircraft could fly 9400 kilometers.

The problem with the motors was allowed to develop a modification of VD-7B. To extend the life of the engine, designers had to reduce its traction to the level of RD-3M. It was 9,500 kG. It is necessary to recognize that, despite the fact that the resource of the motor was increased and increased several times, it never reached the level of RD-3M. Nevertheless, with a general deterioration in performance, the range of flight, due to the economy of the power plant, was 15% higher than the range of the 3MS version.

Modification with motors VD-7B was called 3MN. Externally, it differed from version 3MS only engine hoods. On top of the hoods VD-7B were barred hatches, designed to release into the atmosphere hot air from under the bypass tapes. In flight, the planes were also different: the VD-7B engine left a noticeable smoky trail.

Latest Modifications

In 1960, another version of the aircraft came out, which was called the 3MD. It was characterized by more advanced equipment and improved aerodynamics. The motor remained the same.

In the 60th issue of the aircraft began to decline steadily, and soon it stopped altogether. The country's leadership shifted its priorities toward rocket technology. Therefore, one more modification of the bomber, which received the VD-7P engine and the name 3ME, remained an experimental example. The take-off thrust of the engines increased to 11300 kG. The tests were carried out in 1963. However, the company still recalls the 3M aircraft - the history of the model does not end there.

With the reduction in the number of strategic bombers, some of them (versions 3MS and 3MN) were converted into tankers for refueling. They refueled in the air as "Tu-95", and remained in service with a 3M strike aircraft. The 3M tanker, thus, changed the version of M-4-2. But, in fact, all this was one machine, only with different motors and related communications.

Transport tasks

In the late 70-ies, there was a need for transportation of aggregates of a new missile complex from factories to the Baikonur cosmodrome. Due to the large dimensions, weight and decent range of transportation, none of the types of conveyor could solve this problem. For example, the central tank of the carrier rocket was 40 meters long and 8 meters wide. V. Myasishchev reminded of himself and offered to transport cargo on the fuselage of his bomber. The 3M aircraft was already out of production at that time, and Myasishev himself was the general designer of the OKB re-created in 1967. In 1978, his proposal was accepted. When Vladimir Mikhailovich died (October 14, 1978), his work was continued by V. Fedotov.

In order not to delay the development, construction and testing of the carrier aircraft, three tankers were selected. They were immediately sent for testing to identify weaknesses. As a result, the aircraft received an updated skeleton and new fuselage panels. The tail part was rearranged and lengthened by 7 meters. The plumage became two-kilo. A number of systems and nodes have been improved or replaced. The aircraft were supplied with more powerful engines VD-7M with a shot off-shot camera, the thrust of which reached 11000 kG. The same motors, but with the afterburner, were installed on the Tu-22, but by that time they were no longer produced.

As a result, five configurations of the carrier aircraft were developed, each of which, due to specific dynamic and flight characteristics, was intended for cargo of a certain weight. The model was called 3M-T. One of the three constructed aircraft was transferred to TsAGI for static testing. And one more was equipped with a bar refueling.

In 1980, the transport plane 3M-T was first raised to the sky. And on January 6 next year test pilot A. Kucherenko transported the cargo for the first time. Later, the aircraft was renamed into ZM-T Atlant. On the transporters of this series, more than 150 cargoes were transported to Baikonur. They transported all the large-sized parts of the Energia and Bhutan complexes. The cargo plane 3M, whose photo was once recognized by everyone, was regularly shown on all kinds of aviation holidays, including Mosaeroshow in 1992.

Finally it should be noted that the Tu-134A-3M aircraft, which are sometimes confused with the hero of our story because of the "3M" index in the title, have nothing to do with it. All "Tu-134" are passenger ones. And the Tu-134A-3M airplanes are a VIP version of the agricultural version of 134СХ.

Conclusion

In 2003, 50 years have passed since the first flight of the 4-M aircraft, which became the first-born in the family of Soviet bombers. Surprisingly, the model of the 3M aircraft is still found in the combat units of the Air Force. We just have to admire the talent of designers who managed to build a technique with such a strong potential in the difficult post-war years.