DIS 2VK-107A. VM-14. In the spring of 1945, the design bureau of plant No. 482 began designing a long-range escort fighter (DIS) based on the recently tested Pe-2I dive bomber. Note that both pilots, the pilot and the navigator were in the same cockpit and sat back to back with the possibility of turning the latter.

Armament. A characteristic feature of this aircraft was a very powerful offensive weaponry. In the nose of the fuselage, two (one) B-20 cannons were installed, fixed in a stationary position, and at the bottom of the hull, in a thickening made on the Pe-2I for the suspension of a protruding one-ton bomb, two more cannons of 37 mm caliber, or 45 mm and even two 57 mm guns. For ammunition, respectively, 250 shells, 200 shells and, finally, 175 shells each, it was determined quite enough space in the aircraft body. The mass of a second salvo ranged from 12.3 kg to 17.8 kg. The navigator had one more short-barreled cannon installed on the turret by M.E. Berezina BT-20 for protection from the rear hemisphere.

Construction. All-metal, like all previous "Pawns", especially like the Pe-2I. The innovations were anti-icers on all important components of the aircraft. Due to the tips, the wingspan was slightly increased. The engines were installed in the same places, but with a radically changed cooling system. So, water radiators were placed in the developed wing center section. The oil coolers, along with the air intakes of the carburetors, were spaced out on the outer sides of the engines to the extent limited by the propellers. Engines VK-107 differed from VK-105 in two upper rows of exhaust pipes. Four rows of exhausts were required by the minders due to the extreme increase in the temperature regimes of the VK-107 compared to the VK-105 engine.

Construction of the aircraft began on July 15 and was completed by November 2, 1945. Everywhere the plan was overfulfilled, and the simplified assembly technology contributed to the acceleration of assembly and assembly work in all shops of the enterprise under construction. Recall that V.M. Myasishchev was evacuated to Kazan in 1942 and replaced the chief designer A.I. Putilov, who worked on the Pe-2 series. After the death of V.M. Petlyakov, his place was temporarily taken by A.M. Isakson, continuing to lead the dive bomber series. When he ceased to cope with the frantic pace of work, he was dismissed and appointed the next successor to A.I. Petlyakov. Putilov, whom A.N. Tupolev, recommending Myasishchev in his place. From Kazan, where at the 22 plant Myasishchev still managed to achieve the required performance in the production of "Peshek", his design bureau was re-evacuated to Moscow, where a small area of ​​the former plant No. 133 was allocated to designers and production workers. This fenced patch on Khodynka was named the plant No. 482. The design, model work and construction of future Myasishchev's aircraft began in parallel with the rebuilding of new high-quality hulls intended for the design bureau, laboratories, workshops and other factory services.

It is known that the fine-tuning of the M-107 engines on his I-110 aircraft in the sharaga of plant No. 288 in Omsk was carried out by D.L. Tomashevich. By 1944, he managed to do this at the expense of powerful oil and water radiator groups. Then motors of this type went to experienced Pawns ...

At the end of 1945, the Myasishchevsky DIS entered flight tests, but the end of the war and the transition to jet technology determined the fate of the aircraft, which remained in a single copy.

Photo	Description
	Drawing DIS (VM-14)
	Layout DIS 2VK-107A

In accordance with the order of the NKAP No. 358 of May 27, 1944, OKO Myasishchev was tasked, along with fine-tuning and transferring the Pe-2I for state tests, "to design and build in duplicate and submit for state tests in December 1944 a twin-engine high-speed day bomber with VK-108 engines without small arms with the following data: maximum flight speed at an altitude of 6000 m - 700 km / h; flight range with 1000 kg of bombs inside the fuselage - 2000 km.

In the summer of 1944, the design team headed by V.M. Myasishchev, began the development of the DB-2VK-108 high-speed day bomber (other names used were DB-108 and DSB-2VK-108). Its design was based on the Pe-2I scheme with a further increase in the volume of the fuselage bomb bay. The increased flight weight of the aircraft was fully compensated by the installation of two powerful VK-108 engines with four-bladed VISH-108L-20 propellers. The VK-108 motor practically did not differ in size and weight from the VK-107A, but had a new two-speed supercharger with Polikovsky control vanes and was 150-200 hp. more powerful.

In addition to the propeller group and an enlarged bomb bay (the internal suspension of the shortened FAB-2000 M44 bomb became possible), the new machine differed from the Pe-2I in a modified engine nacelle configuration, improved aerodynamics and larger wheels (1000x350 mm), corresponding to the increased takeoff weight. And although GKO Decree No. 5947 of May 22, 1944 and the order of the NKAP did not provide for equipping the DB-108 with defensive weapons, Myasishchev was soon forced to abandon such radicalism (he took into account the opinion of A.A. Novikov about the Pe-2I). Therefore, on December 10, 1944, at the mock-up commission, a variant with a UB-20 cannon mounted motionless under the pilot's seat, as well as with a tail remote-controlled installation of a DEU (20-mm UB-20 cannon) with an ammunition load of 80 shells was considered.

The aircraft was designed in three versions at once: two-seat VM-16 (Vladimir Myasishchev - project No. 16) for attacks from level flight; diving VM-17 with a third crew member and a four-seat VM-18 with an increased bomb load. The designation of all three variants of the aircraft is DB-108 day bomber with VK-10V engines). The new VK-108 engines designed by V. Ya. Klimov developed 1850 hp near the ground in takeoff mode. s, cruising at an altitude of 4500 m - 1500 hp.

On all versions of the bomber, propeller groups were located on the wing, water and oil radiators of the engines were located in the center section and wing consoles with air intakes in the leading edge and lower adjustable sliding doors. The tricycle undercarriage with tail wheel, spaced tail and 43.1 m² wing were also the same for all DB-108s.

The design of the bomber is all-metal, well suited for mass production.

The crew of the VM-16 was placed in one cockpit, which had good visibility due to the extended glazing of the lower part of the nose of the fuselage. The seat of the navigator-gunner could unfold in flight to fire backwards from the aft remote-controlled movable gun mount.

The front cockpit of the VM-17 aircraft was designed in approximately the same way. However, it placed the upper turret with a 20 mm cannon for shelling the front hemisphere. The cabin of the third crew member was in the rear fuselage. To repel fighter attacks, the gunner had a UB-12.7 heavy machine gun in the turret and a 20-mm cannon in a hatch mount.

Quadruple VM-18 had a significantly enlarged fuselage. In its front part, a separate cabin was equipped for the navigator. The designers and weapons of the bomber were strengthened.

When using the VM-16, VM-17 and VM-18 as long-range escort fighters, and the designers foresaw this possibility, a battery of 37 or 45 mm guns was suspended in the bomb bays.

Photo	Description
	Drawing DB-108 (VM-18)

In accordance with the main purpose - the destruction and suppression of strong enemy fortifications - DB-108 had the ability to carry bombs weighing 1000 and 2000 kg. A two-ton bomb on the VM-16 and VM-17 was suspended in the bomb bay with difficulty, only after it was shortened by trimming the stabilizer. In addition, it was possible to suspend bombs with a total weight of up to 1000 kg under the wing. On the VM-18, due to the new layout of the fuselage, the bomb bay was enlarged. A two-ton bomb entered it without alterations, and the maximum load was no longer 3000, but 4000 kg, taking into account the suspension of additional heavy bombs under the wing.

To carry out a normal takeoff with a maximum load or to reduce the takeoff run at normal takeoff weight, the VM-17 and VM-18 were equipped with an underwing installation of solid rocket boosters.

The first experimental aircraft VM-16 was built by December 30, 1944 and transferred to flight tests. They ran from January to June 1945. In flights with a normal takeoff weight of 9400 kg (empty weight - 6922 kg), the bomber showed a maximum speed near the ground - 575 km / h, and at an altitude of 6000 m - 700 km / h, that is, the highest among all domestic front-line bombers. The practical ceiling of the car is 12,000 m. The flight range with 2 tons of bombs is 2250 km.

In June 1945, the VM-17 dive bomber was completed. Its flight performance was slightly lower than that of the VM-16 due to the increase in takeoff weight (9990 kg with a normal load at an empty weight of 7512 kg) and the installation of brake grids under the wing. The maximum speed of this option near the ground is 545 km/h, at an altitude of 6000 m - 670 km/h. Practical ceiling - 10,000 m.

The negative reaction of the Air Force leadership to the "weakened defensive armament" of the Pe-2I after the completion of the second stage of testing the "Soviet Mosquito" was quite clear. Therefore, in the order of the NKAP No. 42 dated February 5, 1945, the task was to "equip the second experimental DB-108 with a reinforced version of the armament," which additionally included a hatch cannon mount and a UBT machine gun on the pivot of the third crew member - the gunner-radio operator. The construction of this machine was completed on May 25, 1945. With all the imperfections of the new mobile installations made in haste, their introduction was dictated by cruel necessity. It was still not possible to bring the tail DEU suffering from chronic defects. The Soviet aircraft industry managed to finally solve the problem of creating a remote-controlled cannon installation only a few years later, after getting acquainted with the captured German developments and the mobile turrets of the American B-29 bomber.

From the first days of flight tests of the DB-108 prototype, it became obvious that the new engines are even more "raw" and capricious than the VK-107A. Fine-tuning the machine turned out to be an extremely difficult and dangerous business. In one of the test flights on June 5, 1945, a catastrophe occurred - when landing on one engine (the second was on fire and turned off), the pilot Vasilchenko caught on a village house and crashed into another. The leading engineer of the aircraft, L.A., died. Dyakonov and three residents (including two children), and Vasilchenko himself was seriously wounded and miraculously survived. The indirect cause of the disaster was the negligence of the management of the flight test station of plant No. 22, which released the prototype aircraft into flight simultaneously with the planned flight of production aircraft. One of these "pawns" prevented Vasilchenko, who was pulling to land, he had to make a "snake" and lose precious seconds and meters of altitude.

The four-seater version of the DB-108 was built after the VM-17. Like his "older brother", he did not pass full flight tests, since in connection with the end of the war, the serial production of this family of bombers was not planned. However, partial tests and calculated data indicated that the VM-18 had very high performance characteristics. Its speed at the ground with a normal takeoff weight of 10,530 kg reached 542 km/h, and at the most advantageous altitude of 5800 m it exceeded 660 km/h, and the flight range was 2000 km. It is worth noting that for this version of the bomber, the designers provided for the replacement of standard detachable wing consoles with other, larger ones. With such consoles, the total wing area reached 48 m² with a span of 20.6 m. The designers provided for the replacement of consoles for those cases of combat use when it is necessary to achieve a greater flight range without reducing the overall combat load.

Bibliography

• The history of aircraft designs in the USSR, 1938-1950. /V.B. Shavrov /
• Evolution of the Pe-2 /Vladimir Kotelnikov/
• Planes of the World. Heavy fighters of the Second World War / Aviation collection /
• DIS-2VK-107A (VM-14) / Ivanamin Sultanov /