The Tupolev Tu-4 was a piston-engined Soviet strategic bomber that served the
Soviet Air Force from the late 1940s to mid-1960s. It was a reverse-engineered
copy of the American-made Boeing B-29 Superfortress.
Design and development Toward the end of World War II, the
Soviet Union saw the need for a strategic bombing capability similar to
that of the United States Army Air Forces. The Soviet VVS air arm had the
locally designed Petlyakov Pe-8 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 forward bases using B-29 Superfortresses. Joseph Stalin ordered
the development of a comparable bomber. The U.S. twice refused to supply the
Soviet Union with B-29s under Lend Lease. 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 Soviets were neutral in the Pacific War and the
bombers were therefore interned and kept by the Soviets. Despite Soviet
neutrality, America demanded the return of the bombers, but the Soviets refused.
Three repairable B-29s were flown to Moscow and delivered to the Tupolev OKB.
One B-29 was dismantled, the second was used for flight tests and training, and
the third one was left as a standard for cross-reference. The aircraft included 1
Boeing-Wichita −5-BW, 2 Boeing-Wichita −15-BWs and the wreckage of 1
Boeing-Renton −1-BN – three different models from two different production
lines. Only one of the 4 had de-icing boots as used on the Tu-4. With the
Soviet declaration of war against Japan in accordance with the Yalta agreement
to enter the war within 90 days of VE day at about 11pm on August 8, 1945—two
days after the U.S. atomic bombing of Hiroshima and the subsequent entente
with Japan ending, the fourth B-29 was returned to the US along with its crew.
Stalin told Tupolev to clone the Superfortress in as short a time as
possible instead of continuing with his own comparable ANT-64. The
reverse-engineering effort involved 900 factories and research institutes, who
finished the design work during the first year; 105,000 drawings were made.
By the end of the second year, the Soviet industry was to produce 20 copies
of the aircraft ready for State acceptance trials.
The Soviet Union used the metric system, thus sheet aluminum in thicknesses
matching the B-29's imperial measurements were 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,
yet despite these challenges the prototype Tu-4 only weighed about 340 kg
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 and Tupolev had to overcome substantial
resistance in favor of using equipment that was not only already in production
but in some cases better than the American version. Each component made
and each alteration was scrutinized and was subject to a lengthy bureaucratic
process. Differences were limited to the engines, the defensive weapons, the
radio and the identification friend or foe system – the American IFF being
unsuitable. The Soviet engine, the Shvetsov ASh-73 was a development of the
Wright R-1820 but was not otherwise related to the B-29's Wright R-3350 —
the ASh-73 also powered some of Aeroflot's remaining obsolescent
Petlyakov Pe-8 airframes, an 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 harder
hitting and longer ranged Soviet Nudelman NS-23 23mm cannon. Kerber,
Tupolev's deputy at the time, recalled in his memoirs that engineers needed
authorization from a high-ranking general to use Soviet-made parachutes.
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,
piloted by test pilot Nikolai Rybko. Serial production started immediately,
and the type entered large-scale service in 1949. Entry into service of the Tu-4
threw the USAF into a panic, since the Tu-4 possessed sufficient range to
attack Chicago or Los Angeles on a one-way mission, and this may have
informed the maneuvers and air combat practice conducted by US and British air
forces in 1948 involving fleets of B-29s. Some attempts to develop midair
refueling systems were made to extend the bomber's range, but these were
fitted to only a few aircraft. = First public appearance=
The aircraft was first displayed during a flyover at the Aviation Day parade on
3 August 1947 at the Tushino Airport in Moscow. Three aircraft flew overhead. It
was assumed that these were merely the three B-29 bombers that were known to
have been diverted to the USSR during World War II. Minutes later a fourth
aircraft appeared. Western analysts realized that the Soviets must have
reverse-engineered the B-29. The appearance of an obviously
Superfortress-derived Tu-70 transport over the crowd removed any doubt about
the success of the reverse-engineering. Operational history
Eight hundred and forty-seven Tu-4s had been built when production ended in the
Soviet Union in 1952, some going to China during the later 1950s. Many
experimental variants were built and the valuable experience launched the Soviet
strategic bomber program. Tu-4s were withdrawn in the 1960s, being replaced
by more advanced aircraft including the Tupolev Tu-16 jet bomber and the Tupolev
Tu-95 turboprop bomber. 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-1. Variants
Tu-4 main production version, originally
designated B-4 Tu-4 Variants without special
designations: Tu-4 ELINT and ECM
Tu-4 mothership for DFS 346. Tu-4 escort fighter mothership
Tu-4 remotely controlled target drone converted from time expired bombers.
Tu-4 fuel carrier Tu-4 in-flight refuelling testbeds
Tu-4 radiation reconnaissance aircraft Tu-4 communications relay aircraft
Tu-4A nuclear capable bomber used to test
Soviet RDS-1 RDS-3 and RDS-5 nuclear bombs. The standard Tu-4 was not capable
of carrying these weapons. Tu-4D
troop transport. Tu-4K/KS
anti-shipping version, armed with KS-1 Komet missiles carried between the
engines under the wings. Tu-4LL
engine testbed for the Mikulin AM-3 jet engine, the Ivchenko AI-20, Kuznetsov
NK-4 and Kuznetsov 2TV-2F turboprop engines, the Dobrynin VD-3K radial
engine and AV-28 contra-rotating propellers.
Tu-4NM drone launcher aircraft with Lavochkin
La-17 unmanned aerial vehicles carried underwing
Tu-4R long range reconnaissance.
Tu-4T paratroop transport
Tu-4TRZhK liquid oxygen tanker aircraft.
Tu-4UShS navigational trainer.
ShR-1 testbed for Myasishchev M-4 to develop a
bicycle type landing gear. UR-1/-2
testbed for Myasishchev M-4 powered controls.
Tu-4 AWACS Chinese prototype with KJ-1 AEWC,
"AWACS" radar and powered by Ivchenko AI-20K turboprop engines. 2 converted to
allow the Chinese to monitor US nuclear weapons tests in the Pacific.
Tu-70 Airliner derivative, never reached mass
production. Tu-75
Cargo aircraft derivative, never reached mass production.
Tu-79 Tu-4 with M-49TK engines.
Tu-80 Bomber derivative, never reached mass
production. Tu-85
Bomber derivative, never reached mass production.
Tu-94 Tu-4 with turboprop engines.
Operators Soviet Union
Soviet Air Force The Soviet Air Force operated 847
Tupolev Tu-4 bombers between 1948 and early 1960. They were initially used as
long-range bombers. In 1954 the Soviets began phasing out the Tu-4; units
upgraded to Tupolev Tu-16 bombers and, beginning in 1956, to Tupolev Tu-95
bombers. Tu-4s withdrawn from front line units were used for transport duties.
People's Republic of China People's Liberation Army Air Force
On 28 February 1953, Joseph Stalin gave China 10 Tu-4 heavy bombers. These
Tu-4's were refitted with AI-20K turboprop engines in 1966. The last
PLAAF Tu-4 were retired in 1988. In 1967 China attempted to develop its
first airborne early warning aircraft, based on the Tu-4 airframe. The project
was named KJ-1 and mounted a Type 843 rotodome on top of the aircraft.
However, the radar and equipment was too heavy, and the KJ-1 did not meet PLAAF's
requirements. The project was canceled in 1971. The single prototype aircraft
is now on display at the PLAAF museum north of Beijing.
Survivors Tu-4 4114, ex-KJ-1 AEWC, "4114"
Stored at Datangshan, China Tu-4 4134, "4134"
Stored at Datangshan, China Tu-4 unknown, "01"
Stored at the Central Air Force Museum, Monino, Russia
Specifications Data from Tupolev Tu-4 Soviet
Superfortress General characteristics
Crew: 11 Length: 30.179 m
Wingspan: 43.047 m Height: 8.46 m
Wing area: 161.7 m2 Aspect ratio: 11.5
Empty weight: 36,850 kg Gross weight: 47,850 kg
Max takeoff weight: 55,600 kg – 63,600 kg
Powerplant: 4 × Shvetsov ASh-73TK 18-cyl. air-cooled radial piston
engines, 1,790 kW each Propellers: 4-bladed V3-A3 or V3B-A5,
5.06 m diameter Performance
Maximum speed: 558 km/h at 10,250 m Range: 5,400 km at 3,000 m with 63,600
kg take-off weight including 3,000 kg of bombs and 10% fuel reserves
Service ceiling: 11,200 m Rate of climb: 4.6 m/s at 1,000 m
Time to altitude: 5,000 m in 18.2 minutes
Wing loading: 400 kg/m2 Power/mass: 0.11 kW/kg
Armament Guns:
10 × 23 mm Nudelman-Suranov NS-23 aircraft cannon, two cannon in each of
the four turrets and two cannon in the tail barbette
Missiles: 2 × KS-1 Komet standoff missiles
Bombs: 6 × 1,000 kg bombs
or 1 x RDS-1, RDS-3 or RDS-5 nuclear
fission bomb See also
Related development Boeing B-29 Superfortress
Tupolev Tu-70 Tupolev Tu-75
Tupolev Tu-80 Tupolev Tu-85
Aircraft of comparable role, configuration and era
Avro Lincoln Consolidated B-32 Dominator
Messerschmitt Me 264 Related lists
List of bomber aircraft List of military aircraft of the Soviet
Union and the CIS References
= Notes= = Bibliography=
External links Tu-4 Photos at airliners.net, including
PLAAF examples. Tu-4 "Bull" entry at the FAS.org website