Ilyushin Il-18 (1946)
The Ilyushin Il -18 (Russian Ильюшин Ил -18) from 1946 is a four-engine passenger aircraft of the Soviet Ilyushin manufacturer. The guy was equipped with a retractable landing gear, radial engines and a pressurized cabin. The low-wing aircraft had a conventional tail. The first flight took place on 17 August 1946.
Development
The machine is based in their interpretation on the Tupolev Tu- 4 and with their civilian offshoot Tupolev Tu- 70 comparable. The flight tests, which lasted until July 30, 1947 showed a satisfactory flight characteristics. The project was still set. The official reason was mentioned that the originally planned turbocharged engines of the type ASch - 73TK were not available in time. Was further cited the fact that the Tu- 70 could be made cheaper because of the use of about 75 percent of the parts produced in large series Tu- 4. More likely, however, is that aviation at this time simply still did not need such a large civil aircraft in the former USSR. It was therefore only built a machine.
Technical design
The Il -18 had a circular fuselage cross -section with a diameter of 3.5 m. However, in contrast to the simultaneously developed smaller Il -12 it had a pressurized cabin with oval windows.
The wings have been designed as a tapered wing with a high commercial aircraft geometric aspect ratio of 12, which caused a high wing loading (up to 3400 N / m²).
For use on long routes, the Il -18 was equipped with an extensive de-icing system. The nose edges of the wings were heated by engine exhaust gases. For the cockpit windows and the propeller blades there was a chemical de-icing. As an innovation, the nasal edge of the tail were electrically de-iced. For four generators were required.
The main landing gear had four wheels and drove into the engine nacelles forward one. The nose gear was equipped with twin tires and drove to the back. A new feature was the time that the gear doors closed again after lowering the landing gear.
Originally, the Il -18, four diesel engines of the type Atsch -71 should receive. Even before the construction was decided from the experience of flight testing of the Il -12 to use gasoline radial engines of the type ASch - 73K with turbochargers TK -19.
Flight testing
The prototype was built by the summer of 1946. The first flight on August 17, 1946 led the test pilot Vladimir Konstantinovich Kokkinaki by at Moscow airport W. M. Frunze. Since the turbo-compressors were not yet available at this time, the flight altitude was limited to 2000 m. During the flight testing has been shown that the rise could one engine inoperative sure Il -18 with 42.5 t and. With a flying weight of 36 tonnes, it was possible to fly without descent. On August 3, 1947, she was presented publicly on the air parade in Tushino.
Following the decision not to mass produce Il -18, the prototype came to 1950 for various test programs to use. Among other things he was used as a tow plane of the load sailor Il -32. The prototype was given to the registration CCCP - L1789.