Aviation of World War II

DVB-102 - Myasishchev's long-range high-altitude bomber, developed at TsKB-29.

Powerplant - by the beginning of the design, Myasishchev could only rely on the new M-120TK engines developed in KB-26 under the leadership of V.Ya. Klimov. They can be called new only for their unusual layout - three cylinder blocks of the M-105 engine, which began its pedigree with the French "Hispano-Suiza", were arranged in the form of the Latin letter "Y". As a result, the engine developed take-off power, although while on the stand, 1850 hp, and the installed turbochargers had to keep the power of 1430 hp. to heights over 10,000 m.

The high-altitude flight of the aircraft sharply increased its invulnerability from air defense systems. For the life of the crew at high altitudes, it was supposed to create a cabin with a high-altitude system - the air taken from the compressor of the supercharger was supplied to the cabin, creating the required pressure. The crew could breathe this air, but in case of depressurization, it was envisaged to use oxygen masks powered by oxygen cylinders.

On July 24, 1940, the day before Myasishchev was released from prison, the customer approved the draft design of a bomber with two M-120TK liquid-cooled engines (with a turbocharger). In the same summer, the construction of a prototype began, but WWII and the evacuation of TsKB-29 in July 1941 delayed it until the beginning of 1942. In the evacuation, V.M. Myasishcheva continued his work at plant No. 288, created on the basis of aircraft repair shops, in the suburbs of Omsk. Difficulties were created by new engines, turbochargers, the nose support of the landing gear, during the first takeoff, the Shimmy effect was declared, which almost led to an accident.

On February 17, 1942, the plane made its first flight. The report on state tests noted that "... the plane is simple on takeoff, stable on the run. Side winds at an angle of 60 ° on takeoff (with a wind speed of 5 m / s) are hardly felt.

In level flight, the aircraft is sufficiently stable, the resulting rudder loads are completely removed by trimmers.

On turns and turns, the aircraft is stable and obeys the rudders well. At roll angles of 50 ° -70 °, significant loads arise on the rudders, especially the ailerons and elevator. The aircraft turns well with roll angles up to 70 °. The landing technique is much simpler than that of the Pe-2, Er-2 and 103-B.

Flight on one engine with a flight weight of 13000 kg is possible at speeds up to 260 km / h. With a lot of weight, not tested due to poor performance of the propeller group. "

* - The ceiling reached

Armament - three 20-mm ShVAK cannons, one 7.62-mm ShVAK machine gun and two 12.7-mm BK machine guns or three BK machine guns , bomb load - 1000-4000 kg.

On June 20, 1942, on the aircraft was installed M-71 air-cooled radial engines, developed at the A.D. Shvetsova. Although this engine was previously installed on the fighters of the N.N. Polikarpov and S.A. Lavochkin, was clearly "raw" and required refinement. After the third flight due to a breakdown of the left engine, tests were interrupted until a new M-71 was received.

In August 1943, the crew of V.I. Zhdanov performed the first long-distance flight on the DVB-102 on the route Omsk-Kazan-Moscow (Chkalovskaya airfield), which made it possible to determine the range of the vehicle. The finishing of the "102nd" car was carried out under the direction of N.G. Nurova. In Moscow, or rather, at the experimental plant of the Air Force Research Institute in Chkalovskaya, on the plane, they began training on the installation of forced ASh-71F engines with TK-3 turbochargers, which were obtained only in 1944.At the same time, in accordance with the layout of the understudy, the nose the cockpit, replacing the drop-shaped pilot's canopy, shifted to the left side, with a new one, which occupied almost the entire width of the fuselage. This significantly improved the visibility and made it possible for the navigator to replace the pilot in a long flight.

Despite the fact that the M-71F engine, which developed a take-off power of 2250 hp, passed 50-hour bench tests, its poor performance was constantly manifested in flights.

DVB-102 with M-71F engines, due to the failure of one of them and the lack of new ones in the industry, and its backup were mothballed along with other aircraft of the Myasishchev Design Bureau. Having stood for a long time near the hangar of plant No. 240 at the Frunze Central Aerodrome, these planes were written off and scrapped. But the ideas embodied in DVB-102 did not die. Suffice it to note that the design feature of its wing, together with the team of designers OKB-482, migrated to OKB-240 S.V. Ilyushin. A wing with a technological split along the chord line along the span was used on the Il-22 and Il-28 aircraft.

Photo	Description
	Drawing DVB-102

Bibliography

• V.M. Myasishchev`s aircrafts/ Rusavia. N. Yakubovich, V. Lavrov. /
• "Sleeping Beauty" / AiK 2017-05 Sergey Moroz /
• The history of aircraft designs in the USSR, 1938-1950. / V.B. Shavrov /

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It is known from theory that it is more profitable to fly long distances at angles of attack close to the maximum aerodynamic quality and at economic operating modes of the engines, which leads to a decrease in speed. The flight at maximum speeds is carried out at angles of attack corresponding to the minimum frontal resistance and at maximum engine operating conditions. It was very difficult to combine high speed and range in an airplane. The reason for this was the absence of powerful high-altitude engines, effective means of wing mechanization and, accordingly, a rather low specific load on the wing. But there was a certain "golden mean" that allowed flying at acceptable speeds over long distances. This required raising the plane as high as possible. At altitudes close to the stratosphere, in rarefied air, you can fly at angles of attack close to the maximum aerodynamic quality mode, with a fairly high speed.

For example, when installing TK-1 turbochargers on TB-3, the maximum speed at an altitude of 8500 m remained the same as before it was at an altitude of 4200 m. To maintain a level flight mode, as follows from the laws of aerodynamics, the angles of attack of the aircraft should increase by more than one and a half times, i.e. from 3 ° -4 ° to 5 ° -6 °, in proportion to the decrease in air density.

Despite the existence in the USSR of the Central Institute of Aircraft Motor Building, a number of factories for the production of engines and several design bureaus, aircraft motor building was one of the weakest links in the aviation industry. The production of new types of engines in the USSR was usually preceded by the acquisition of licenses abroad, and this factor was the impetus for the introduction of advanced technologies both in the pre-war and post-war years.

It was supposed, after replacing the wing and engines with Charomsky diesel engines with DVB-102, to reach a range of 20 thousand km and fly through the South Pole. On August 10, 1945 the pilots Gromov, Baidukov, Yumashev, Danilin addressed this proposal in a letter to Stalin. However, by this time the country had no time for record flights and had to abandon this idea.