The 3M aircraft is a Soviet strategic bomber that has served for about four decades. There have been many different events in the history of this aircraft. He eventually gained an ambiguous reputation. Someone calls this aircraft an emergency model, and someone considers it a great achievement. One way or another, the 3M aircraft, the history of which was the subject of our conversation, deserves attention as a serious project of Soviet aircraft designers.
Prerequisites for creating
In the late 1940s, when nuclear weapons appeared, the need arose for their transportation and mobile delivery to the right place. The military complex needed bombers, which, according to their characteristics, could exceed the models produced at that time by 1.5-2 times. So the concept of a strategic bomber was formed. America began to develop such aircraft earlier. In 1946, two American aviation companies at once - Boeing and Conver - began developing a strategic bomber. So, in 1952, the B-52 and B-60 aircraft made their first flight. Both models differed from their predecessors by a high ceiling, as well as impressive speed and range.
Start of development
In the USSR, similar developments started with a significant delay. It all started with the fact that designer V. Myasishchev, who worked as a professor at the Moscow Aviation Institute, proposed to the government the creation of a strategic bomber capable of flying up to 12 thousand kilometers. As a result, after consulting with experts, I. Stalin decided to entrust Myasishchev with the development of the aircraft proposed by him, but set strict deadlines. Development was to be completed on May 24, 1951. The Council of Ministries of the USSR ordered the construction of the aircraft recreated after the closure of OKB-23 MAP. Myasishchev became the chief designer. Soon, the Air Force Commander-in-Chief approved the tactical and technical requirements for the machine. The maximum flight range was to be at least 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 under 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 designer, aerodynamics and rigidity at the same time. V. Myasishchev at that time was engaged in the formation of units, divisions and brigades. The team was created in parallel with the bomber. In a short time, a draft sketch was prepared and approved. Along with this, production technology was developed, because before the USSR did not produce such large and heavy aircraft. The machine needed new sizes of profiles and materials, as well as the nomenclature.
The bomber should have had good aerodynamic performance, develop great speed and be as light as possible. Designers paid a lot of attention to the shape of the wing. During the first six months of development in the wind tunnel, TsAGI tested many models until the optimal one was found. The created wing was relatively light, had flexible end parts and was made according to the caisson construction. It resisted flutter well. 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 engines when working in different modes. The nozzles were deployed in horizontal and vertical planes at 4 degrees. This measure was necessary to divert the hot gas stream from the fuselage and tail.
Equipment
The power plant of the bomber included four powerful turbojet engines designed by Mikulin. Their thrust was 8700 kG. When designing the power plant, a bet was placed on maximum reliability. By the way, according to the initial project, the aircraft was to be equipped with three engines with a thrust of 13,000 kG. However, the Dobrynin Design Bureau did not have time to prepare prototypes of these engines in such a short time.
Separately, it is worth noting the variant of the bomber chassis chosen by the designers. To study the dynamics of the movement of such a heavy aircraft on the runway, a special expert group was organized. Initially, several chassis designs were considered: standard with three supports, multi-support and bicycle. During the tests, the chassis, built according to the bicycle scheme with the front “climbing up” trolley and side racks located at the ends of the wings, proved to be the best. The aircraft steadily drove along the runway and took off with the maintenance of the required take-off run.
The head pair of wheels mounted on the front bogie was oriented in a small range of angles (+ 15 0 ). When the pair turned, the direction of movement of the trolley changed, and after it the direction of the entire aircraft changed. In the “sprinting” mode, the front pair of wheels became uncontrollable. At the final stage of the takeoff, the nose of the aircraft rose, and the angle of attack increased. The participation of the pilot in take-off was minimal. This scheme was tested at the Tu-4 flying laboratory, the three-leg chassis of which was specially replaced by a bicycle one. A model of a separate electrically operated trolley was also built. Chassis prototypes underwent a full range of tests and confirmed their suitability for use on a bomber.
The bomb load of the aircraft was 24 tons, and the largest bomb caliber - 9000 kg. Thanks to the RPB-4 radar sight, targeted bombing was provided. The bomber had contented powerful weapons for defense. It included six automatic guns with a caliber of 23 mm. They were placed in pairs on three rotary installations in the upper, lower and rear fuselage. The crew, consisting of eight people, was housed in two pressurized cabins. The seats ejected through the hatches down.
Test
By December 1952, a prototype bomber was built. And on January 20 of next year, the car was first lifted into the air. The flight was led by test pilot F. Opadchiy. From that day, factory tests of the specimen began in full swing. 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 6,700 meters was equal to 947 kilometers per hour. The practical ceiling (maximum flight range) with a weight of 138 tons was 12,500 meters. The designers managed to place a huge amount of fuel tanks on board. They housed 132390 liters of fuel. However, the maximum refueling was limited to 123600 liters.
In 1954, the second prototype was connected to the tests, which had a nose section shortened by 1 m, an increased wing area and a number of other, less significant improvements. Engineers began to prepare for mass production of a bomber. By this time, in honor of the designer Myasishchev, the car received the name "Airplane M". 3M is the index that was assigned to the model later. And at first it was called the M-4.
The tests went far from the best. By most characteristics, the aircraft was fully consistent with the task, but the main requirement - the maximum flight range with 5 tons of bombs on board - it could not be satisfied. After a number of improvements, the bomber was nevertheless adopted. But the question of insufficient range remained open.
Improvements
To solve the above problem, the bomber was installed with more powerful and at the same time economical RD-3M engines, which were developed by P. Zubets. The bomber with a new power plant received the 3M index. In fact, the motors were modified versions of the AM-3A engine. The maximum thrust was increased to 9500 kG. Moreover, the RD-3M installation had an emergency mode, which in the event of a failure of one motor increases the remaining power up to 10 500 kG. With such power equipment, the 3M aircraft was able to reach a speed of 930 km / h and fly non-stop at distances of up to 8100 km.
The search for opportunities to increase flight range did not end there. The second experimental version was equipped with a refueling system developed at Alekseev Design Bureau. Over the cockpit appeared "rod" for receiving fuel. Well, the tanker was equipped with an additional tank, equipment for pumping and a winch.
While the 3M Myasishchev plane was being created, in parallel, work was underway to develop its high-altitude version, which received the working name 2M. The designers intended to install four VD-5 turbojet engines on it at once - on pylons spaced under the wing. However, the design of the “skyscraper” was stopped, since the 3M version was able to achieve its design characteristics.
3M airplane: development
Despite the good performance, the model continued to develop. March 27, 1956 the first flight on a 3M car took place. The aircraft received new VD-7 engines, which had a thrust of 11,000 kG. At the same time, they weighed less and consumed less fuel. At first, the aircraft was equipped with two new engines, and by 1957 - all four. Thanks to the installation of wings of a new configuration and the improvement of the characteristics of the horizontal tail, the aerodynamic qualities of the aircraft have increased markedly. In addition, the volume of fuel tanks was increased. This was achieved, among other things, thanks to the hanging 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, the characteristics of which we are discussing today, received a lightweight design. However, its weight still rose to 193 tons, and with hanging tanks even more - up to 202 tons. Over time, the front of the fuselage gained a new layout. It became possible to move the antenna station from under the fuselage to the bow, which was extended by 1 meter. Thanks to the new navigation equipment, the 3M aircraft could conduct effective bombing from high altitude 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, hanging tanks and maximum bomb load, this figure exceeded 15,000 km. To conquer such a distance, the aircraft needed about 20 hours. Thus, the prospect of using it as an intercontinental strategic bomber appeared. The 3M plane was exactly the machine that Myasischev originally wanted to create, taking on great responsibility and securing the support of Stalin.
Another interesting quality of 3M is the fact that it can be used as a distant marine torpedo bomber. Torpedoes became part of the regular armament, but they were used extremely rarely. The first tests of the marine version of the bomber were carried out on a prototype M-4.
Merit 3M
After the latest modifications, the aircraft was put into service and put into serial production. In 1959, pilots N. Goryainov and B. Stepanov, together with their crews, set 12 world records on it. Among them was a lift with a 10-ton load to a height of more than 15 kilometers and a lift with a 55-ton load to a height of 2 kilometers. In the world records tables, the aircraft was named 201M. In the same year, test pilot A. Lipko and his team set seven records of flight speed on a closed route, with varying degrees of load. With a load of 25 tons, he developed a speed of 1028 km / h. In official documents, the 3M Myasishchev aircraft was again named differently - 103M.
When the new strategic bomber entered service, some of the earlier versions of the M-4, which differed only in their weak power plant, were converted into refueling tanks.
Operational problems and new motor
Despite the highest performance, the plane 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, in order to carry out routine repairs, the motors were often changed. While problems with the VD-7 were being resolved, the same RD-3M was installed on the aircraft, with which the successes of the model began. With this power plant, it was called 3MS. Of course, compared with 3M, the plane showed worse results, but it was much better than its prototype - the M-4 version. In particular, without refueling the ZMS aircraft could fly 9,400 kilometers.
The problem with the motors was allowed by the development of the VD-7B modification. To extend the life of the engine, the designers had to reduce its thrust to the level of RD-3M. It amounted to 9500 kgf. It is worth recognizing that, despite the fact that the motor resource was increased and increased several more times, it still did not reach the RD-3M level. Nevertheless, with a general deterioration in performance, the flight range, due to the efficiency of the power plant, was 15% higher than the range of the 3MS version.
Modification with motors VD-7B was called 3MN. Outwardly, it differed from the 3MS version only in engine hoods. On top of the hoods of the VD-7B were barred hatches designed to discharge into the atmosphere of hot air from under the bypass tapes. In flight, the aircraft also differed: the VD-7B engine left a clearly visible smoky trail.
Recent Modifications
In 1960, another modification of the aircraft was released, which was called 3MD. She was distinguished by more advanced equipment and improved aerodynamics. The motor remains the same.
In the 60s, the release of the aircraft began to systematically decline, and soon completely stopped. The country's leadership shifted priorities towards rocket technology. Therefore, another of the modifications of the bomber, which received the VD-7P engine and the name 3ME, remained a prototype. Takeoff thrust of engines increased to 11300 kG. The tests were carried out in 1963. However, the company will still remember the 3M aircraft - the history of the model does not end there.
With a reduction in the number of strategic bombers, some of them (versions 3MS and 3MN) were converted into tankers for refueling. They refueled both the Tu-95 and the remaining 3M strike aircraft. The 3M tanker, therefore, changed the version of M-4-2. But, in fact, it was all one machine, only with different motors and related communications.
Transport tasks
At the end of the 70s, there was a need to transport units of a new missile complex from factories to the Baikonur cosmodrome. Due to the large size, weight and decent range of transportation, none of the types of conveyor could solve this problem. For example, the central tank of the launch vehicle was 40 meters long and 8 meters wide. V. Myasischev reminded of himself and offered to carry goods on the fuselage of his bomber. The 3M plane at that time was already discontinued, and Myasishchev himself was the general designer of the design bureau recreated 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 frame and new fuselage panels. The tail part was rearranged and extended by 7 meters. The plumage became two-keel. A number of systems and components have been improved or replaced. The aircraft were supplied with more powerful VD-7M engines with the afterburner removed, the thrust of which reached 11,000 kG. The same motors, but with an 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 cargoes of a certain weight. The model is called 3M-T. One of the three aircraft built was transferred to TsAGI for static tests. And one more was equipped with a refueling bar.
In 1980, the 3M-T transport aircraft was first raised to the sky. And on January 6 of the following year, test pilot A. Kucherenko first transported cargo on it. Subsequently, the aircraft was renamed the “ZM-T Atlant”. The carriers of this series transported more than 150 cargoes to Baikonur. They transported all the bulky parts of the Energia and Bhutan complexes. A 3M cargo plane, a photo of which everyone once recognized, was regularly shown at all kinds of aviation festivals, including at the Moscow Air Show in 1992.
In conclusion, it is worth noting that the Tu-134A-3M aircraft, which are sometimes confused with the hero of our story because of the 3M index in the name, have nothing to do with it. All Tu-134s are passenger. And the Tu-134A-3M aircraft are at all a VIP modification of the agricultural version 134.
Conclusion
In 2003, it was 50 years since the first flight of the 4-M aircraft, which became the first-born in the family of Soviet bombers. Surprisingly, the 3M aircraft model is still found in the combat units of the Air Force. We can only admire the talent of designers who managed to build equipment with such a strong potential in the difficult post-war years.