At the beginning of 1948, the Design Bureau was tasked with designing and building an experimental bomber Il-38 with turbojet engines TR-3 with take-off thrust of 4,600 kgf. The range of his flight with a bomb load of 2000 kg was to be 2500 km, and the maximum speed at an altitude of 1000 km / h. On the plane it was required to provide defensive armament in the composition: forward - one 23 mm caliber gun, back - two-gun installation. The deadline for transferring the machine to state tests was set for the summer of 1949. It was supposed to conduct studies of the behavior of a bomber with a wing with a large sweep angle on an airplane. In the summer of the same year, the development of a new machine was interrupted by another government decree on the beginning of the design and construction of the IL-30 front-line bomber with the same engines.
It was proposed to provide the new machine with a flight range of 3,500 km, a maximum speed of at least 10 ° km / h and a normal bomb load of 2,000 kg. In the midst of the ongoing “struggle” for the recognition of the IL-28 aircraft, the Chief Designer, trying to use its design well studied during the tests, decided to use a larger wing on the designed prototype machine. However, purges performed at TsAGI showed the undesirability of choosing such a wing configuration due to a significant deterioration in its load-bearing properties in a given speed range. Ultimately, numerous studies and recommendations made it possible to stay on the swept wing, which has a slight narrowing and aerodynamic walls on the upper surface.
The location of the wing in the middle of the fuselage cross section, which is more advantageous in aerodynamic terms, made it necessary to abandon the placement of engines on pylons and install them in nacelles, closely pressed against the lower wing skin. The two main supports of the bicycle-type chassis, first used on a domestic bomber, were installed in the fuselage, and the side support legs in the cowl fairings of the engines. The bomber’s crew, consisting of a pilot, navigator, radio operator gunner and gunner gunner, was housed in two pressurized cabins and had protective armor. The defensive armament of the bomber consisted of two front fixed guns NR-23, which were controlled by the pilot, two similar cannons in the upper turret of the Il-V 12, remotely controlled by the gunner-radio operator, and two of the same guns in the rear aft IL-Kb. The increased size of the bomb compartment made it possible to accommodate 4000 kg of various bombs in the reload version, and the installed complex of modern radio and electronic equipment at that time allowed the crew to carry out combat missions with confidence and with a high degree of reliability at any time, regardless of meteorological conditions.
The aircraft was built in the summer of 1949 and performed several runs on the runway of LII. However, on this his short biography was cut short. New design ideas and scientific recommendations incorporated in the machine raised doubts about the reliability and strength of its design at the flight speeds specified by the decree. This was especially true for a thin swept wing, in which high-speed profiles with a small relative thickness were used. A more thorough study of the behavior of such a wing at transonic speeds, its ability to withstand aerodynamic phenomena and loads resulting from this, could be studied in advance on the failed IL-38 bomber. However, now, in the absence of the necessary operating experience, this required lengthy theoretical and experimental checks.
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