The Tupolev Tu-4 (;

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 ...

: Bull) is a piston-engined

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 ...

strategic bomber A strategic bomber is a medium- to long-range Penetrator (aircraft), penetration bomber aircraft designed to drop large amounts of air-to-ground weaponry onto a distant target for the purposes of debilitating the enemy's capacity to wage war. Unl ...

that served the

Soviet Air Force The Soviet Air Forces (, VVS SSSR; literally "Military Air Forces of the Union of Soviet Socialist Republics"; initialism VVS, sometimes referred to as the "Red Air Force") were one of the air forces of the Soviet Union. The other was the Sovie ...

from the late 1940s to the mid-1960s. The aircraft was a copy of the American

Boeing B-29 Superfortress The Boeing B-29 Superfortress is a retired American four-engined propeller-driven heavy bomber, designed by Boeing and flown primarily by the United States during World War II and the Korean War. Named in allusion to its predecessor, the Bo ...

, having been

reverse-engineered Reverse engineering (also known as backwards engineering or back engineering) is a process or method through which one attempts to understand through deductive reasoning how a previously made device, process, system, or piece of software accompl ...

from seized aircraft that had made emergency landings in the USSR.

Design and development

Toward the end of

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 ...

, the Soviet Union saw the need for a strategic bombing capability similar to that of the Western Allies. The Soviet VVS air arm had the locally designed

Petlyakov Pe-8 The Petlyakov Pe-8 () was a Soviet heavy bomber designed before World War II, and the only four-engine bomber the USSR built during the war. Produced in limited numbers, it was used to bomb Berlin in August 1941. It was also used for so-called " ...

four-engined "heavy" in service at the start of the war, but only 93 had been built by the end of the war and the type had become obsolete. The U.S. regularly conducted bombing raids on Japan from distant

Pacific The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean, or, depending on the definition, to Antarctica in the south, and is bounded by the cont ...

forward bases using B-29 Superfortresses.

Joseph Stalin Joseph Vissarionovich Stalin (born Dzhugashvili; 5 March 1953) was a Soviet politician and revolutionary who led the Soviet Union from 1924 until Death and state funeral of Joseph Stalin, his death in 1953. He held power as General Secret ...

ordered the development of a comparable bomber. The U.S. twice refused to supply the Soviet Union with B-29s under

Lend Lease Lend-Lease, formally the Lend-Lease Act and introduced as An Act to Promote the Defense of the United States (),

."Aircraft Deliveries."
''airforce.ru''. Retrieved: 21 September 2007. However, on four occasions during 1944, individual B-29s made emergency landings in Soviet territory and one crashed after the crew bailed out. In accordance with the

Soviet–Japanese Neutrality Pact The , also known as the , was a non-aggression pact between the Soviet Union and the Empire of Japan signed on April 13, 1941, two years after the conclusion of the Soviet-Japanese Border War. The agreement meant that for most of World War II, ...

, the Soviets were neutral in the

Pacific War The Pacific War, sometimes called the Asia–Pacific War or the Pacific Theatre, was the Theater (warfare), theatre of World War II fought between the Empire of Japan and the Allies of World War II, Allies in East Asia, East and Southeast As ...

and so the bombers were interned and kept by the Soviets. Despite Soviet neutrality, the U.S. demanded the return of the bombers, but were refused."Soviet Union Impounds and Copies B-29."
National Museum of the USAF. Retrieved: 17 July 2017. Three repairable B-29s were flown to Moscow and delivered to the

Tupolev Tupolev ( rus, Туполев, , ˈtupəlʲɪf), officially United Aircraft Company Tupolev - Public Joint Stock Company, is a Russian aerospace and Arms industry, defence company headquartered in Basmanny District, Moscow. UAC Tupolev is succes ...

OKB OKB () is a transliteration of the Russian initials for "" (), which translates to "Experimental Design Bureau." It could also mean or "Special Design Bureau" in english. During the Soviet era, OKBs were closed institutions working on design and ...

. One B-29 was dismantled, the second was used for flight tests and training, and the third was left as a standard for cross-reference.Kerber, Leonid
"Tu-4 bomber epic"
. ''militera.lib.ru'': a compilation of articles published in 1988–1990 (in Russian). Retrieved: 29 December 2009. The aircraft included one Boeing-Wichita –5-BW, two Boeing-Wichita –15-BWs and the wreckage of one Boeing-Renton –1-BN, comprising three different models from two different production lines, at Wichita and Renton. Only one of the four had

deicing boot A deicing boot is a type of ice protection system installed on aircraft surfaces to permit a mechanical deicing in flight. Such boots are generally installed on the leading edges of wings and flight control surfaces, control surfaces (e.g. hori ...

s, as would be used on the Tu-4. The fourth B-29 was returned to the US along with its crew with the end of the Soviet-Japanese peace. The Soviets declared war on Japan two days after the

atomic bombing of Hiroshima On 6 and 9 August 1945, the United States detonated two atomic bombs over the Japanese cities of Hiroshima and Nagasaki, respectively, during World War II. The aerial bombings killed between 150,000 and 246,000 people, most of whom were civil ...

, in accordance with the

Yalta Agreement The Yalta Conference (), held 4–11 February 1945, was the World War II meeting of the heads of government of the United States, the United Kingdom, and the Soviet Union to discuss the postwar reorganization of Germany and Europe. The three sta ...

. Stalin told Tupolev to duplicate the Superfortress in as short a time as possible instead of continuing with his own comparable ANT-64/Tu-10. The reverse-engineering effort involved 900 factories and research institutes, which finished the design work during the first year, and 105,000 drawings were made. By the end of the second year, the Soviet industry was to produce twenty copies of the aircraft, ready for state acceptance trials. The Soviet Union used the

metric system The metric system is a system of measurement that standardization, standardizes a set of base units and a nomenclature for describing relatively large and small quantities via decimal-based multiplicative unit prefixes. Though the rules gover ...

and so sheet aluminium in thicknesses matching the B-29's U.S. customary measurements was unavailable. The corresponding metric-gauge metal was of different thicknesses. Alloys and other materials new to the Soviet Union had to be brought into production. Extensive re-engineering had to take place to compensate for the differences, and Soviet official strength margins had to be decreased to avoid further redesign. Despite those challenges, the prototype Tu-4 weighed only more than the B-29, a difference of less than 1%. The engineers and suppliers of components were under pressure from Tupolev, Stalin, and the government to create an exact clone of the original B-29 to facilitate production. Tupolev had to overcome substantial resistance to use equipment that was not only already in production but also sometimes superior to that found on the B-29s. Each alteration and every component made was scrutinized and was subject to a lengthy bureaucratic decision process. Kerber, then Tupolev's deputy, recalled in his memoirs that engineers needed authorization from a high-ranking general to use Soviet-made parachutes. Differences were limited to the aforementioned sheet-metal gauges, the engines, the defensive weapons, the radio (a later model used in lend-lease B-25s was used in place of the radio in the interned B-29s) and the

identification friend or foe Identification, friend or foe (IFF) is a combat identification system designed for command and control. It uses a transponder that listens for an ''interrogation'' signal and then sends a ''response'' that identifies the broadcaster. IFF syst ...

(IFF) system since the American IFF was obviously unsuitable. The Soviet

Shvetsov ASh-73 The Shvetsov ASh-73 was an 18-cylinder, air-cooled, radial aircraft engine produced between 1947 and 1957 in the Soviet Union. It was primarily used as the powerplant for the Tupolev Tu-4 heavy bomber, an unlicensed, reverse engineered copy of t ...

engine was a development of the

Wright R-1820 The Wright R-1820 Cyclone 9 is an American radial engine developed by Curtiss-Wright, widely used on aircraft in the 1930s through 1950s. It was produced under license in France as the Hispano-Suiza 9V or Hispano-Wright 9V, and in the Soviet Uni ...

but was not otherwise related to the B-29's

Wright R-3350 The Wright R-3350 Duplex-Cyclone is an American twin-row, supercharged, air-cooled, radial aircraft engine with 18 cylinders displacing nearly . Power ranged from , depending on model. Developed before World War II, the R-3350's design requi ...

. The ASh-73 also powered some of

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 remaining obsolescent

airframes, a much-earlier Soviet four-engined heavy bomber, whose production was curtailed by higher-priority programs. The B-29's remote-controlled gun turrets were redesigned to accommodate the Soviet Nudelman NS-23, a harder-hitting and longer-ranged cannon. Additional changes were made as a result of problems encountered during testing related to engine and propeller failures, and equipment changes were made throughout the aircraft's service life. The Tu-4 first flew on 19 May 1947 and was flown by test pilot Nikolai Rybko. Serial production started immediately, and the type would enter large-scale service by 1949. The aircraft was first displayed during a flyover on 3 August 1947 at the Tushino Aviation Day parade. At first three aircraft flew over and the Western observers assumed that they were merely the three B-29 bombers which they knew had been diverted to the Soviet Union during World War II. Minutes later a fourth aircraft appeared, and the observers realized the Soviets had reverse-engineered the B-29. Entry into service of the Tu-4 threw the

U.S. Air Force The United States Air Force (USAF) is the air service branch of the United States Department of Defense. It is one of the six United States Armed Forces and one of the eight uniformed services of the United States. Tracing its origins to 1 ...

into panic since the aircraft possessed sufficient range to attack

Chicago Chicago is the List of municipalities in Illinois, most populous city in the U.S. state of Illinois and in the Midwestern United States. With a population of 2,746,388, as of the 2020 United States census, 2020 census, it is the List of Unite ...

Los Angeles Los Angeles, often referred to by its initials L.A., is the List of municipalities in California, most populous city in the U.S. state of California, and the commercial, Financial District, Los Angeles, financial, and Culture of Los Angeles, ...

on a one-way mission, and that may have informed the maneuvers and air combat practice conducted by US and British air forces in 1948 involving fleets of B-29s. The tests were conducted by the RAF

Central Fighter Establishment The Central Fighter Establishment was a Royal Air Force formation that dealt with the development of fighter aircraft tactics which was formed on 4 September 1944 as a nucleus at RAF Tangmere. It also tested new fighter aircraft and equipment, a ...

and co-operative US B-29 groups and involved demonstration of recommended methods of attack against B-29/Tu 4-type bombers using RAF

Gloster Meteor The Gloster Meteor was the first British jet fighter and the Allies' only jet aircraft to engage in combat operations during the Second World War. The Meteor's development was heavily reliant on its ground-breaking turbojet engines, pioneere ...

and

de Havilland Vampire The de Havilland DH100 Vampire is a British jet fighter which was developed and manufactured by the de Havilland, de Havilland Aircraft Company. It was the second jet fighter to be operated by the Royal Air Force, RAF, after the Gloster Meteo ...

jet fighters. The Soviets developed four different midair refueling systems to extend the bomber's range, but these were fitted to only a few aircraft, and only a small number of the final design were installed on operational aircraft before the Tu-4 was superseded by the

Tu-16 The Tupolev Tu-16 (USAF/DOD reporting name Type 39; NATO reporting name: Badger) is a twin-engined jet strategic heavy bomber used by the Soviet Union. It has been flown for almost 70 years. While many aircraft in Soviet service were retired af ...

Operational history

A total of 847 Tu-4s had been built when production ended in the Soviet Union in 1952, some of which went to China during the later 1950s. Many experimental variants were built and the experience launched the Soviet strategic bomber program. Tu-4s were withdrawn from Soviet service in the 1960s, being replaced by more advanced aircraft including the

Tupolev Tu-16 The Tupolev Tu-16 (USAF/DOD reporting name Type 39; NATO reporting name: Badger) is a twin-engined jet strategic heavy bomber used by the Soviet Union. It has been flown for almost 70 years. While many aircraft in Soviet service were retired af ...

jet bomber (starting in 1954) and the

Tupolev Tu-95 The Tupolev Tu-95 (; NATO reporting name: "Bear") is a large, four-engine turboprop-powered strategic bomber and missile platform. Maiden flight, First flown in 1952, the Tu-95 entered service with the Soviet Long Range Aviation, Long-Range Avia ...

turboprop bomber (starting in 1956). By the beginning of the 1960s, the only Tu-4s still operated by the Soviets were used for transport or airborne laboratory purposes. A Tu-4A was the first Soviet aircraft to drop a nuclear weapon, the

RDS-3 RDS-3 () was the third atomic bomb developed by the Soviet Union in 1951, after the RDS-1 and RDS-2. It was called ''Marya'' in the military. The bomb had a composite design with a plutonium core inside a uranium shell, providing an explosive powe ...

Variants

;Tu-4: main production version, originally designated B-4 ;Tu-4 Variants without special designations: :Tu-4

ELINT Signals intelligence (SIGINT) is the act and field of intelligence-gathering by interception of ''signals'', whether communications between people (communications intelligence—abbreviated to COMINT) or from electronic signals not directly u ...

and

ECM ECM may refer to the following: Economics and commerce * Engineering change management * Equity capital markets * Error correction model, an econometric model * European Common Market Mathematics * Lenstra's Elliptic curve method for factor ...

:Tu-4 mothership for the DFS 346A.Gordon, 2002, p. 54(Note:other DFS346 prototypes were carried by one of the

Boeing B-29 The Boeing B-29 Superfortress is a retired American four-engined propeller-driven heavy bomber, designed by Boeing and flown primarily by the United States during World War II and the Korean War. Named in allusion to its predecessor, the Bo ...

s interned during the war). :Tu-4 escort fighter mothership (Project Burlaki) :Tu-4 remotely controlled

target drone A target drone is an unmanned aerial vehicle, generally remote controlled, usually used in the training of anti-aircraft crews. One of the earliest drones was the British DH.82 Queen Bee, a variant of the Tiger Moth trainer aircraft operation ...

converted from time expired bombers. :Tu-4 fuel carrierGordon, 2002, p. 53 :Tu-4

in-flight refuelling Aerial refueling ( en-us), or aerial refuelling ( en-gb), also referred to as air refueling, in-flight refueling (IFR), air-to-air refueling (AAR), and tanking, is the process of transferring aviation fuel from one aircraft (the tanker) to ano ...

testbeds (four different systems were trialled) :Tu-4 radiation reconnaissance aircraftGordon, 2002, p. 43 :Tu-4 communications relay aircraft ;Tu-4A: Nuclear capable bomber used to test Soviet

RDS-1 The RDS-1 (), also known as Izdeliye 501 (device 501) and First Lightning (), was the nuclear bomb used in the Soviet Union's first nuclear weapon test. The United States assigned it the code-name Joe-1, in reference to Joseph Stalin. It was de ...

and RDS-5 nuclear bombs. The standard Tu-4 was not capable of carrying these weapons. ;Tu-4D: Troop transport (300 conversions). Also known as Tu-76. ;Tu-4K/KS: Anti-shipping version, armed with

KS-1 Komet The Raduga KS-1 Comet ( (Крылатый Снаряд: winged projectile), NATO reporting name: AS-1 Kennel) was a Soviet short range air-to-surface missile, primarily developed for anti-ship missions. It was carried on two aircraft, the Tupole ...

missiles carried between the engines under the wings. ;Tu-4LL: Engine testbed for the

Mikulin AM-3 The Mikulin AM-3 (also called RD-3M) was a turbojet engine developed in the Soviet Union by Alexander Mikulin.Gunston 1989, p. 104. Design and development The development of the high-performance single-shaft engine began in 1948. The engine was ...

jet engine, the

Ivchenko AI-20 The Ivchenko AI-20 is a Soviet turboprop engine developed by the Ivchenko design bureau in the 1950s. It has been built in large numbers, serving as the powerplant for both the Antonov An-12 transport and the Ilyushin Il-18 airliner. Design and ...

Kuznetsov NK-4 The Kuznetsov NK-4 is a turboprop engine, designed by the Kuznetsov Design Bureau. Development Development of the NK-4 began on September 27, 1955 at the Kuznetsov Design Bureau. Factory tests were passed on April 17, 1956 and state tests were ...

and

Kuznetsov 2TV-2F Kuznetsov, Kuznyetsov, Kuznetsoff, or Kouznetsov (masculine, ) or Kuznetsova (feminine, ) is the third most common Russian surname, an equivalent of the English "Smith" (derived from a Russian word ''kuznets'' that means ''blacksmith''). Men * Al ...

turboprop engines, the Dobrynin VD-3K radial engine and AV-28 contra-rotating propellers. ;Tu-4NM: Drone launcher aircraft with

Lavochkin La-17 The Lavochkin La-17 was the first Soviet Union, Soviet unmanned aerial vehicle (UAV) to reach operational service. The first versions were developed in the early 1950s, and remained in service into the 1980s. Early development The La-17 was desi ...

unmanned aerial vehicle An unmanned aerial vehicle (UAV) or unmanned aircraft system (UAS), commonly known as a drone, is an aircraft with no human pilot, crew, or passengers onboard, but rather is controlled remotely or is autonomous.De Gruyter Handbook of Dron ...

s carried underwing ;Tu-4R: Long-range reconnaissance.Gordon, 2002, p. 42 ;Tu-4T: Paratroop transport (one example only) ;Tu-4TRZhK:

Liquid oxygen Liquid oxygen, sometimes abbreviated as LOX or LOXygen, is a clear cyan liquid form of dioxygen . It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an application which is ongoing. Physical ...

tanker aircraft. ;Tu-4UShS: Navigational trainer. ;ShR-1: Testbed for

Myasishchev M-4 The Myasishchev M-4 ''Molot'' (), USAF/DoD reporting name "Type 37", Air Standardization Coordinating Committee, ASCC reporting name Bison) was a four-engined strategic bomber designed by Myasishchev, Vladimir Mikhailovich Myasishchev and manufa ...

to develop a bicycle-type landing gear. ;UR-1/-2: Testbed for

powered controls. KJ-1

;Tu-4 AWACS: Chinese prototype with

KJ-1 AEWC The KJ-1 (from zh, s=空警, p=Kōng Jǐng, short for 空中预警 ''kōngzhōng yùjǐng'' meaning "airborne early warning") was a Chinese experimental airborne early warning (AEW) aircraft, based on a Tupolev Tu-4 bomber aircraft (itself bein ...

airborne early warning and control An airborne early warning and control (AEW&C) system is an airborne radar early warning system designed to detect aircraft, ships, vehicles, missiles and other incoming projectiles at long ranges, as well as performing command and control of the ...

radar and powered by Ivchenko AI-20K

turboprop A turboprop is a Gas turbine, gas turbine engine that drives an aircraft Propeller (aeronautics), propeller. A turboprop consists of an intake, reduction drive, reduction gearbox, gas compressor, compressor, combustor, turbine, and a propellin ...

engines. Two converted to allow the Chinese to monitor US nuclear weapons tests in the Pacific. ; Tu-70: Airliner, never reached mass production. ; Tu-75: Cargo derivative, never reached mass production. ;Tu-79: Tu-4 powered by M-49TK engines. ; Tu-80: Long-range bomber development, never reached mass production. ; Tu-85: Long-range bomber development, never reached mass production. ;Tu-94: Tu-4 powered by Kuznetsov TV-2 turboprop engines.

Operators

; *

The Soviet Air Force operated 847 Tupolev Tu-4 bombers between 1948 and early 1960, initially as long-range bombers. The first regiment to be re-equipped on the Tu-4 was the 185th Guards Aviation Regiment of the 13th Guards Bomber Aviation Division, stationed at Poltava Air Base in the

Ukrainian SSR The Ukrainian Soviet Socialist Republic, abbreviated as the Ukrainian SSR, UkrSSR, and also known as Soviet Ukraine or just Ukraine, was one of the Republics of the Soviet Union, constituent republics of the Soviet Union from 1922 until 1991. ...

. The training of personnel was carried out in

Kazan Kazan; , IPA: Help:IPA/Tatar, ɑzanis the largest city and capital city, capital of Tatarstan, Russia. The city lies at the confluence of the Volga and the Kazanka (river), Kazanka Rivers, covering an area of , with a population of over 1. ...

, at the 890th long-range bomber regiment, turned into a training unit. The pilots of the 890th Regiment had extensive experience flying American

Boeing B-17 Flying Fortress The Boeing B-17 Flying Fortress is an American four-engined heavy bomber aircraft developed in the 1930s for the United States Army Air Corps (USAAC). A fast and high-flying bomber, the B-17 dropped more bombs than any other aircraft during ...

es and

Consolidated B-24 Liberator The Consolidated B-24 Liberator is an American heavy bomber, designed by Consolidated Aircraft of San Diego, California. It was known within the company as the Model 32, and some initial production aircraft were laid down as export models desi ...

aircraft. In March 1949 the received Tu-4s; the 121st Guards received Tu-4Rs in 1953. In 1954 the Soviets began phasing out the Tu-4 as

bombers entered service and, beginning in 1956, to

bombers. Tu-4s withdrawn from front line units were used for transport duties. ; *

People's Liberation Army Air Force The People's Liberation Army Air Force, also referred to as the Chinese Air Force () or the People's Air Force (), is the primary aerial warfare service of the People's Liberation Army. The PLAAF controls most of the PLA's air assets, includi ...

On 28 February 1953,

gave China ten Tu-4 heavy bombers, and in 1960 two additional aircraft configured as navigational trainers arrived in

Beijing Beijing, Chinese postal romanization, previously romanized as Peking, is the capital city of China. With more than 22 million residents, it is the world's List of national capitals by population, most populous national capital city as well as ...

. 11 Tu-4s were refitted with AI-20K turboprop engines between 1970 and 1973. The last PLAAF Tu-4 was retired in 1988. In 1969, China developed its first

airborne early warning An airborne early warning and control (AEW&C) system is an airborne radar early warning system designed to detect aircraft, ships, vehicles, missiles and other incoming projectiles at long ranges, as well as performing command and control of t ...

aircraft based on the Tu-4 airframe. The project was named KJ-1 and mounted a Type 843

rotodome A radome (a portmanteau of "radar" and "dome") is a structural, weatherproof enclosure that protects a radar antenna. The radome is constructed of material transparent to radio waves. Radomes protect the antenna from weather and conceal an ...

above the fuselage of the aircraft. However, due to clutter noise the KJ-1 failed to meet the PLAAF's requirements. The project was canceled in 1979 although further projects were proposed based on Tu-4 platform. The airframe was already obsolete however and the Tu-4 was ruled out for future developments. The single prototype is displayed at the PLAAF museum north of Beijing.

Survivors

;Tu-4 ''4114'' (c/n 2805601), ex-KJ-1 AEWC, "4114" :Stored at Datangshan,

China China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...

"Photo of the Tu-4 (4114, cn 2806501) AWACS example exhibited in the Datangshan Museum, China."
''airliners.net''. Retrieved: 29 December 2009. ;Tu-4 ''4134'' (c/n 2205008), "4134" :Stored at Datangshan,

;Tu-4 ''unknown'' (c/n 2805103), "01" :Stored at the

Central Air Force Museum The Central Air Force Museum () is an aviation museum in Monino, Moscow Oblast, Russia. A branch of the Central Armed Forces Museum, it is one of the world's largest aviation museums, and the largest for Soviet aircraft, with a collection includi ...

Monino Monino () is an urban locality (a work settlement) in Shchyolkovsky District of Moscow Oblast, Russia, located east of Moscow. Population: History Monino was founded in the Muninskaya Wasteland () on August 23, 1792. The name "Monino" or "M ...

Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...

"Photo of the Tu-4 exhibited in the Central Air Force Museum in Monino, Russia."
''airliners.net''. Retrieved: 29 December 2009.

Specifications (Tu-4)

References

Notes

Bibliography

* * * * * * * {{Authority control Tu-0004 1940s Soviet bomber aircraft Four-engined tractor aircraft Soviet Union–United States relations Tu-04 Mid-wing aircraft Aircraft first flown in 1947 Four-engined piston aircraft Aircraft with retractable tricycle landing gear