Myasishchev DVB-202 / DVB-302
The most modern heavy bomber of the USSR during the Second World War was the Pe-8 "Flying Fortresses" competition. The first version of the long-range bomber DVB-2O2 was proposed by V.M. Myasishchev during the war.
In 1942, when no one could say with certainty who would win the raging war, Myasishchev and Tupolev were asked to develop four-engine bombers with M-71TK-M engines, airtight cabins and cannon armament. A maximum speed of 500 km / h was set at an altitude of 10,000 m, a range of 5000 km with two bombs of 5000 kg and 6000 km with a bomb load of seven to eight tons. The draft project was to be prepared by September 15, 1943.
Raul Colon reports that little "effort was invested in the development of a new type of heavy bomber to replace the outmoded Pe-8 during the first two years of the war. It was not until the autumn of 1943, that Soviet Russia began to emphasized the development of such platforms. In early 1944 the Soviet Unionís State Committee for Defense (GKO) passed a resolution calling for the immediate development of a massive four engine heavy bomber that could strike anywhere within the European Continent.... The Flying Fortress Contest, as the competition was referred to, began in earnest in the summer of 1944."
In 1944, the requirements for a long-range bomber changed. By the Resolution of the State Defense Committee, A.N.Tupolev was instructed to design an aircraft with AM-43 engines and turbochargers TK-300B, which soon received the serial number "64". S.V.Ilyushin was instructed to develop the Il-14 with AM-43 engines with a direct fuel injection device, and V.M. Myasishchev and IF. Nezval were guided by star-shaped air cooling engines Sh-72. It is interesting that only to the decision on the bomber A.N.Tupolev prepared an annex entitled "Measures to ensure the construction of four-engine aircraft ..."
The TTT of the Air Force set the following flight-technical characteristics for the long-range bomber:
- the maximum speed at a design altitude of 10,000 m should be 630 km / h;
- lifting time to a height of 10 000 m - 40 min;
- practical ceiling - 12 000 m;
- the flight range at V = 0.8 max. at an estimated altitude of 10,000 m with a bomb load of 4 tons - 6,000 km;
- the take-off run with fully filled tanks and 10 tons of bombs inside the fuselage - 600 m;
- take-off distance up to climbing 25 m - not more than 1200 m;
- landing speed without bombs with 25% fuel reserve - 140 km / h;
- length of run - 400 m;
- The crew of the aircraft - 11 people (two pilots, two navigators, four riflemen and one flight technician, radar operator and radio operator).
According to the decree, the collective of V.M.Myasishchev (OKB-482) developed and submitted to the People's Commissariat in late December 1945 a draft design bomber DVB-202. When preparing the project, the OKB carried out a lot of work on the overall arrangement of the entire machine in several variants. Together with TsAGI, the wing layout was selected by selecting the most favorable elongation and profiles. The options for deploying remote small arms that provide spherical shelling have been worked out in detail, and the screw-motor group of the ASh-72TK engines has been developed. Calculations were carried out for the strength, aerodynamics, as well as for the altitude, hydraulic and electrical equipment of the aircraft. In parallel with these works, the OKB produced working drawings of the front cabin, and even its full-scale layout was built.
In the process of working out the draft design, the possibilities of using not only the AH-72TK, but also other engines were considered: VK-109 and AM-46TK. Thus, with the installation of VK-109 engines, the aircraft's flight weight, in comparison with the version equipped with the AH-72TK, decreased somewhat, decreased by 10-15 km / h and the maximum speed, but the maximum range from 5000 kg of bombs increased by 1000 km.
When working on the DVB-202 project, the American experience in building heavy B-29 bombers and, of course, the experience gained in the development and flight tests of DVB-102 was taken into account. Therefore, the flight performance of this aircraft was significantly higher than the data of the US B-29 bomber.
Only the calculated range in the DVB-202 was slightly lower than that of the B-29. This was due to the fact that the Americans, because of their distance from the bases of possible adversaries, were forced to build aircraft with a large range of action. For the Soviet Union the range factor was of less importance, and by reducing the range it was possible to increase other characteristics of the aircraft: climb rate, ceiling and speed. With the available range, the DVB-202 in its range captured Great Britain, France, part of Spain, Italy, as well as part of North Africa, including Tunisia, the Suez Canal, Upper Egypt, the northern part of the Persian Gulf, carrying 5000 kg of bombs. Thus, the requirements for the continental bomber were fulfilled completely, and at the intercontinental range at the time did not fly.
The aircraft had three airtight cabins. In the forward cockpit there were pilots, navigators, a radio operator, a flight technician and a gunner of the upper installation. Workstations of navigators were located ahead of the pilots. In the middle sealed cabin - the arrows of the lower and upper units. In the rear (tail) hermetic cabin was the arrow of the tail unit. The radio operator was stationed in one of the cabins with the provision of conditions for working with radars.
The most serious attention was paid to the armament of the aircraft and its rational deployment. On the plane it was planned to install five cannon points with 10 guns of 20-23 mm caliber:
- for firing at the upper hemisphere, two mobile units with two coupled cannons with circular firing on the horizon and with angles of firing vertically upwards 80 ', down from the side 10'. The stock of shells for each gun is 400 pieces;
- for firing at the lower hemisphere - two mobile units for two coupled cannons with circular firing on the horizon with angles vertically upward + 3`, down 80`. Stock of shells per gun 400 pieces;
- for the firing of the rear hemisphere, a mobile tailing installation of two guns with angles of firing along the horizon + 80` and vertically + 60` Reserve of shells of 400 pieces per gun. It was provided for the installation on the plane of one or two guns of 37 mm caliber.
The gun control was remote and was carried out from sighting posts located in sealed cabins. The aircraft was provided with a central control post and aiming at several shooting points. To conduct the aiming of the cannon (from the upper, lower and stern points), automatic synchronous collimating sights were used to ensure shooting up to 1200-1500 m. Automatic range detection was provided by radio range meters.
The normal bomb load of the aircraft was 10,000 kg. The maximum bomb load is 20,000 kg. Inside, the fuselage suspension provided a suspension of normal loading bombs for various caliber variants. Holders of internal and external suspension allowed the following main variants of bomb loading: 1xFAB-10000; 2xFAB-5000; 2xFAB-4000; 8xFAB-2000; 12xFAB-1000; 24xFAB-500; 40xFAB-250 or 70xFAB-100.
For targeted bombing, an integrated sighting device consisting of a synchronous sight, a stabilizer of direction, a course sensor connected to the pilot and the autopilot is installed in the forward fuselage. The aircraft was provided with equipment with a radar installation, which ensures the performance of bombing because of clouds.
All members of the crew had armor protection from fire damage from the rear hemisphere. Reservation of pilots provided protection for each pilot behind in the cone + 30` from the longitudinal axis of the aircraft. The pilots and arrows were armored from below and from the sides, and the arrows of the upper and lower cannon units had additional rear-end (in the horizontal plane + 30` and in the vertical plane, taking into account the angles of the gunshot). Booking navigators in conjunction with the booking of pilots provided each of them in working position a solid protection from the fire from the rear hemisphere in the cone + 30`. The armor was designed to protect against 25 mm cannon shells from a distance of 200 m. Thus, even in the early 1950s, the newest American jet fighters armed with large-caliber machine guns could not effectively repel the attacks of the Myasischev strategists.
The increased attention was paid to the very design of the aircraft. The cockpits of the pilots and the forward part of the fuselage provided a good view to each pilot in the sides, up and straight, forward to 10 "below the horizon. Both pilots were provided with a view through the upper and combat glazing of the cockpit, the engines and the chassis of the aircraft, as well as viewing behind the flying aircraft (during flight by formation). The glazed forward part of the front airtight cockpit provided the navigators with a complete view of the front hemisphere. In the working corners of the scope, the glazing did not give distortions and ruptures.
The design of the airframe of the aircraft provided for the possibility of its use in transport and landing versions, while, after the aircraft was modified in the factory, it was ensured:
- placing in the fuselage of a group of paratroopers up to 70 people, ensuring that the entire group is thrown out within 15 seconds;
- loading of dimensional cargoes into the fuselage, for which a door with a size of 2350 mm in width and 2000 mm in height (type C-47) was provided;
- Exterior suspension of cargo bridges;
- the anti-skid angle with allowance for braking was not less than 25 'with the maximum front operating centering. The design of the aircraft ensured the quick and convenient dismantling, installation, verification and convenient operation of all equipment installed on the aircraft.
During the design of the Air Force machine, gradually getting acquainted with the real samples of Western aviation equipment, as well as giving in to information on the machines being designed, raised the bar of demands for a new domestic bomber higher and higher. Therefore, it is not surprising that by the end of 1944 OKB-482 came to the conclusion that it was necessary to work out a new design for a four-engine bomber with data exceeding the characteristics of the original project both in speed and range, and in terms of bomb load. The new project received the code DVB-302.
Far high-altitude heavy bomber DVB-302 with powerful small arms, performing strategic bombing in distant rear, day and night, unaccompanied by fighters, has become the further development of the DVB-202 project. From the variants of the aircraft application, in contrast to the previous project, only one option was worked out - a bomber. The creation and launch of the DVB-302 in serial production was to signify a decisive step forward not only in aircraft construction, but also in a number of related industries. In accordance with VM Myasishchev's principles, under the condition of simultaneous and coordinated shift in all these branches, the creation of such an aircraft was quite possible, and was not much more complex than the full copying of the B-29.
Several factors influenced the choice of the airplane layout. Initially, it was planned to place two 5,000 kg bombs inside the bomb compartment. However, this was not possible, since the location of bombs nearby or one above the other required too much fuselage midship, which adversely affected the mass and flight data of the aircraft. The location of the bombs, one by one, entailed an excessively long cargo hold, which is impossible both for constructive reasons and because of the large take-off of the alignments when one of the five-ton bombs is dropped. Therefore, it was decided to place in the fuselage only one five-ton bomb. The size of this bomb was such that placing it inside the fuselage required the location of the wing from above. Thus, with the chosen load, the high-order scheme is rational.
In February 1946, by order No. 61 of the NKAP, signed by the new People's Commissar, M.V. Khrunichev, OKB-482 Myasischev closed. Vladimir Mikhaylovich Myasishchev was dismissed from the post of chief designer and director of the plant. Order NKAP, signed by the Deputy People's Commissar for Experimental Aircraft AS. Yakovlev on March 8, 1946, Myasishchev was appointed dean of the aircraft building faculty of the Moscow Aviation Institute and part-time acting professor of the department "Design and Engineering of Aircraft", saving him the salary of the chief designer and cards of limit and literary supply.
Simultaneously, all work on the subjects of OKB-482 stopped. The prospective aircraft OKB were not finished: bombers DVB-102, DB-IV-108, VB-109, jet RB-17, projects DVB-202 and DVB-302. OKB-482 ceased to exist, but the technical solutions born within its walls continued to excite the minds of the customer.
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