The Ilyushin Il-18 (

NATO reporting name NATO uses a system of code names, called reporting names, to denote military aircraft and other equipment used by post-Soviet states, former Warsaw Pact countries, China, and other countries. The system assists military communications by providi ...

: Clam) was a

Soviet The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...

four-engined

airliner An airliner is a type of airplane for transporting passengers and air cargo. Such aircraft are most often operated by airlines. The modern and most common variant of the airliner is a long, tube shaped, and jet powered aircraft. The largest ...

designed and built by

Ilyushin The Open joint-stock company , public joint stock company Ilyushin Aviation Complex, operating as Ilyushin () or as Ilyushin Design Bureau, is a Russian aircraft manufacturer and design bureau, founded in 1933 by Sergey Ilyushin , Sergey Vladimir ...

immediately after

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. Although the aircraft itself was successful, its Shvetsov ASh-73TK engines were too unreliable for civilian use and were further needed to equip the

Tupolev Tu-4 The Tupolev Tu-4 (; NATO reporting name: Bull) is a piston-engined Soviet Union, Soviet strategic bomber that served the Soviet Air Force from the late 1940s to the mid-1960s. The aircraft was a copy of the American Boeing B-29 Superfortress, ha ...

bomber, so it was cancelled in 1948.

Development

The Il-18 was developed to meet

Aeroflot PJSC AeroflotRussian Airlines (, ), commonly known as Aeroflot ( or ; , , ), is the flag carrier and the largest airline of Russia. Aeroflot is headquartered in the Central Administrative Okrug, Moscow, with its hub being Sheremetyevo Interna ...

's need for a high-altitude, long-range aircraft to fly its long-haul national and international routes. It was conceived as a cantilever low-wing

monoplane A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple wings. A monoplane has inherently the highest efficiency and lowest drag of any wing con ...

, powered by four Charomskii ACh-32

diesel engine The diesel engine, named after the German engineer Rudolf Diesel, is an internal combustion engine in which Combustion, ignition of diesel fuel is caused by the elevated temperature of the air in the cylinder due to Mechanics, mechanical Compr ...

s, as initially used in the Ilyushin Il-12, with a tricycle

landing gear Landing gear is the undercarriage of an aircraft or spacecraft that is used for taxiing, takeoff or landing. For aircraft, it is generally needed for all three of these. It was also formerly called ''alighting gear'' by some manufacturers, s ...

. To improve the wing's lift-to-drag ratio and the aircraft's maximum speed, the wing was given a very high

aspect ratio The aspect ratio of a geometry, geometric shape is the ratio of its sizes in different dimensions. For example, the aspect ratio of a rectangle is the ratio of its longer side to its shorter side—the ratio of width to height, when the rectangl ...

of 12. It was intended to operate from both paved and unpaved

runway In aviation, a runway is an elongated, rectangular surface designed for the landing and takeoff of an aircraft. Runways may be a human-made surface (often asphalt concrete, asphalt, concrete, or a mixture of both) or a natural surface (sod, ...

s with a length of less than . Its main wheels were larger than normal to handle the rough surfaces. The pressurized fuselage was circular in cross-section, which provided room for cargo and baggage compartments under the cabin floor. A variety of seating plans were under consideration, ranging from 66 seats to 27 sleeping berths, but no decision had been made before it was canceled. Before the Il-18 had made its first flight its engines were changed to the Shvetsov ASh-73TK radial piston engine because they were entering production, unlike the diesels.Gordon, p. 189 They drove four-blade AV-16NM-95 variable pitch

propeller A propeller (often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon a working flu ...

s. Electro-thermal deicing boots were fitted on the leading edges of the wings, horizontal and vertical tail, driven by four engine-driven electric generators. A

bleed air Bleed air in aerospace engineering is compressed air taken from the compressor stage of a gas turbine, upstream of its fuel-burning sections. Automatic air supply and cabin pressure controller (ASCPC) valves bleed air from low or high stage engine ...

deicing De-icing is the process of removing snow, ice or frost from a surface. Anti-icing is the application of chemicals that not only de-ice but also remain on a surface and continue to delay the reformation of ice for a certain period of time, or pr ...

system was fitted for the

cockpit A cockpit or flight deck is the area, on the front part of an aircraft, spacecraft, or submersible, from which a pilot controls the vehicle. The cockpit of an aircraft contains flight instruments on an instrument panel, and the controls th ...

glazing and propeller blades. The first flight of the Il-18 was made on 18 August 1946, in a sixty-passenger configuration, even though the turbosuperchargers for its engines had not been fitted. To save time Sergey Ilyushin gave the order to commence flight tests without them. However, this proved to be in vain because the manufacturer's flight tests were not concluded until 30 July 1947 as the turbo-superchargers were not delivered in a timely manner. Other problems were the short time between overhauls for the ASh-73TKs, initially only 25 hours, and the disintegration of one engine on 25 June 1947. Flight characteristics were docile and the passenger cabin proved to be far more comfortable than those of the

Lisunov Li-2 The Lisunov Li-2 (NATO reporting name: Cab), originally designated PS-84, was a license-built Soviet-version of the Douglas DC-3. It was produced by Factory #84 in Khimki, Moscow-Khimki and, after the factory's evacuation in 1941, at the Tash ...

, the

C-47 Skytrain The Douglas C-47 Skytrain or Dakota ( RAF designation) is a military transport aircraft developed from the civilian Douglas DC-3 airliner. It was used extensively by the Allies during World War II. During the war the C-47 was used for troo ...

or the Il-12. It had a comfortable margin of power that allowed it to continue to cruise if one or even two engines weren't running. Its engines were in short supply as they were needed to power the

and they were not yet reliable enough for economical use so the aircraft was canceled.Gordon, pp. 190–91 The prototype was displayed at the 1947 air display at Tushino where it led a formation of Il-12 airliners. Later it was fitted with a towing shackle and used for flight tests of the heavy Ilyushin Il-32 glider, as it was one of the few aircraft available powerful enough to tow the glider.Gordon, p. 191 It was flown well into the early 1950s although its ultimate fate is unknown.Gordon, p. 191

Specifications

References

;Notes ;Bibliography * * * {{Ilyushin aircraft Il-018 (1947) 1940s Soviet airliners Abandoned civil aircraft projects Four-engined tractor aircraft Low-wing aircraft Aircraft first flown in 1946 Four-engined piston aircraft Aircraft with retractable tricycle landing gear Glider tugs

Development

Specifications

See also

References