Tupolev Tu-4 (Bull)
Strategic Heavy Bomber Aircraft
The Tupolev Tu-4 Bull was nothing more than a Soviet reverse-engineered copy of the famous American Boeing B-29 Superfortress
Authored By: Staff Writer | Last Edited:
During World War 2, the Soviet Union was threatened by both the Empire of Japan to the East and Nazi Germany to the West. Its commitment to the war effort along two fronts required a basic stable of medium-sized bomber aircraft that could reach either frontline. The primary power of the Soviet Union was its Long-Range Aviation but this force served to manage the rather limited group of several dozen Petlyakov Pe-8 bombers. As the war began drawing to a close, the West - in particular the United States - stood as the new enemy of the Soviet Union and this posed a serious challenge to their current crop of bombers that might be called to action in the event of all out war. The new Soviet nuclear program was also kick-started in 1943 and this further relied upon a successful long-range, high-flying weapons delivery platform. The Americans did supply the Soviet Union with tons of war goods via Lend-Lease during their fight against Germany (contrary to Stalin's declarations) and among this booty included Douglas DC-3 transports and North American B-25 medium bombers. However, neither of these airframes could be viably converted for the more appropriate role at hand. The Soviets did manage to "requisition" some four-engined Boeing B-17 Flying Fortresses and Consolidated B-24 Liberators which had landed on Soviet soil by emergency but these aircraft were limited in their own right, particularly concerning the modern battlefield, and beginning to pass their prime altogether.
Conversely, the United States was enjoying success with its new Boeing B-29 Superfortress four-engined high altitude, long range heavy bomber which made regular visits over the Japanese mainland from bases afar. The need for such an aircraft was brought about by the vast expanses of ocean-scape the US military needed to cover in their fight against the Japanese Empire. Fearing a technological advantage for the Americans, Soviet leader Josef Stalin called for a design of similar scope and function to the B-29.
In 1944, the Soviet concerns of Tupolev and Myasishchev were charged with development of such an aircraft but neither held the know-how to make it possible. Initial designs were stymied due to the technological requirements involved and any further work on these early projects was altogether dropped. Fortune found the Soviets however when, during the course of 1944, three B-29s had landed during emergencies after completing their missions over the Japanese mainland. These B-29s promptly became property of Stalin and the technological barriers limiting the initial Soviet efforts were now lifted. The Tupolev concern was then ordered to simply copy the American design - thusly giving rise to the Tupolev "Tu-4". First flight of the prototype was recorded on May 19th, 1947 with the aircraft formally adopted for service in 1949. Production of the "new" bomber began that same year and spanned into 1952 to which 847 examples were ultimately produced. The Tu-4 saw operational service with the Soviet Air Force and would subsequently be passed on to allied China during the 1950s. In all, the Soviets took possession of three complete B-29 bombers (the most famous of these being "Ramp Tramp") and a fourth that had crash-landed in Siberia according to the USAF. Its crews were detained for months while undergoing questioning before being released - such was the Soviet modus operandi.
The Soviets did little to hide the fact that their Tu-4 was simply a reverse-engineered copy of the American B-29. The type followed the American-made product closely in both form and function - every rivet amazingly accounted for. Essentially, the Tu-4 incorporated Soviet weaponry, engines and gauges to suit the Soviet need for the aircraft still largely retained the B-29's cigar-shaped fuselage complete with its heavily glazed cockpit flight deck. Weapon stations inherent in the B-29 were faithfully located in their proper locations about the Soviet design. The wings remained mid-mounted monoplanes extending out a distance away from the fuselage to which each carried a pair of large engine nacelles sporting massive four-bladed propellers. The empennage was dominated by the decidedly Boeing-trademark - a large, curved vertical tail fin with applicable horizontal planes. The undercarriage was nothing more than two-wheeled main landing gear legs under the wings and the two-wheeled nose leg under the cockpit floor. The Tu-4 required a full operating crew of eleven personnel to operate the various onboard systems. Power was supplied by 4 x Shvetsov ASh-73TK 18-cylinder, air-cooled, radial piston engines each delivering 2,400 horsepower. This provided the aircraft with a top speed of 347 miles per hour, a range of 3,355 miles and a service ceiling of 36,745 feet. In comparison the B-29 was powered by 4 x Wright R-3350-23/23A turbosupercharged radial piston engines of 2,200 horsepower for a top speed of 357 miles per hour, a range of 5,600 miles and a service ceiling of 32,000 feet and carried 20,000lbs of internal ordnance while being defensed by 12 x 12.7mm Browning heavy machine guns and 1 x 20mm cannon.
Defense for the Tu-4 was provided for by a network of 10 x 23mm Nudelman-Suranov NS-23 series aerial cannons. Two cannons were fitted across four separate turrets, two found along the top and two found along the bottom of the fuselage. The standard bomb load was made up of 6 x 2,205lb conventional bombs though these - in the event of nuclear war or to be used in the deterrent role - would have been replaced by a single RDS-1, RDS-3 or RDS-5 nuclear bomb. An anti-ship version of the aircraft brought about use of a pair of KS-1 "Komet" anti-ship missiles.
The main production "Bull" model was known simply under the "Tu-4" designation. The aforementioned anti-ship variant was developed from this to become the "Tu-4K" and appropriately armed with KS-1 "Komet" anti-ship missiles. Two further developments of the Tu-4 bomber were also proposed with refinements becoming the abandoned Tu-80 and Tu-85 "Barge" designations - only one and two prototypes, respectively, were produced. A dedicated cargo transport was unveiled as the Tu-75 while a passenger airliner version became the Tu-70 "Carl". Neither of these two designs ever entered large-scale serial production, each only appearing in "one-off" prototypes. The Tu-4 was first identified by Western observers in the August 3rd, 1947 Tushino Airport Aviation Day celebration in Moscow. Three flew over the crowd during the festivities followed by a fourth - which proved the Soviets held the mastery of adequately copying advanced American technology. The Tu-4 then became a permanent fixture of the growing Cold War landscape and placed Western targets within reach of nuclear weapons for the first time in history - a fact that stunned American warplanners in the West.
In February of 1953, the Soviets delivered ten Tu-4 bombers to neighboring China and it was from this that the Chinese attempted to develop their own "AWACS" aerial radar platform featuring Ivchenko AI-20K engines under the "K-1" project designation from 1967 onwards. The endeavor eventually failed and ended with the project's cancellation in 1971. The Chinese continued use of the Tu-4 as a long-range strategic bomber until 1988.
The Soviet Union managed their Tu-4s in a frontline role up until the 1950s to which the type began giving way to the newer breed of Tupolev Tu-16 "Badger" strategic bombers. These went on to have successful careers ultimately being produced in over 1,000 examples. The last Soviet Air Force Tu-4 was retired in the early 1960s.
The B-29 allowed the Soviets to close a technology gap and lay the foundation for perhaps its greatest Cold War aircraft initiative - the Tu-95 "Bear" bomber still to come.