Tu-4 BULL - Origins

In the first days of June 1945, AN Tupolev and his first deputy AA Arkhangelsky were urgently summoned to the Kremlin to JV Stalin. As Arkhangelsky recalled later, Stalin immediately went on to the point: "Comrade Tupolev, we decided to copy the US B-29 bomber, you will learn the details from Shakhurin." The famous aircraft designer was confused by such a statement. His deputy, violating the sudden silence, cheerfully reported: "The task of the party and government will, of course, be fulfilled." And what else could they say in such a situation? Try to explain, that the Soviet aviation industry was not in a position to organize the serial production of most of the B-29 units and components? Suggest to create a domestic machine with similar characteristics? And how long will it take to implement this project? The decree of the State Defense Committee was adopted on June 6, 1945.

Of reference for the development of B-4 included in the plan of an experimental aircraft EI in 1946, but on 26 February 1946 a Decree of the Government approved its highlights: a normal take-off weight - 54500 kg, LHS - 61250 kg, speed no less than 470 km/h at an altitude of 10500 m-560 km/h during normal flight and with a bomb load of 1500 kg range required not less than 5000 kmwith 5000 kg of bombs and a take-off weight 6000 kg-61250 km, with 8000 kg of bombs is 4900 km (the latter requirement in June 1946 was changed: 7120 kg bombs-3000 miles). The plane was supposed to install engines Al-73TK with driving centrifugal supercharger and turbochargers. Plant and State testing engines planned for October 1946 and August 1947, respectively.

In mid 1945 the three American B-29 bombers were moved from the far East to Moscow. One plane was transferred to the Flight-test institute in Zhukovski to train pilots for preparing flight training manuals, the second plane was completely broken up to study its' design to make the design drawings, and the third was left as a standard for comparison. Each separate unit had its own team of designers and engineers. Each unit or part weighed, photographed, and described. Any equipment was subjected to spectral analysis to identify the material. Following thorough reverse engineering of the B-29, (down to the minutest of detail), OKB-156 began to build the Soviet copy of the B-29. The project received the highest priority and was under direct control of the Politbureau, and targeted for completion within two years.

However, to just repeat the B-29 was impossible. The Soviet Union did not have the opportunity to reproduce many details, and even in B-29, aluminum cladding with a thickness of 1/16 was used, and in the USSR - a metric system of units. However, the cloning of the aircraft was completed successfully. The group of designers and designers Tupolev copied even the color interior scheme and repair patch General HH Arnold Special.

The differences between the B-29 and the Tu-4 were hidden inside. The powerful Wright R-3350 engine at 2,200 hp found in the B-29 was unavailable. Tu-4 equipped with a version of the copy of this engine, the ASh-73TK with a centrifugal supercharger and two turbochargers. The first version of the engine was inferior in power to Wright R-3350. The 12.7 mm caliber from the B-29 could not be produced, so the Tu-4 was equipped with air guns. The massive B-29 tires were beyond the power of Soviet industry, so agents were sent to the Western military market to produce suitable tires.

Americans thickness plating was 1/16 of an inch. But the Soviet Union did not have a plant for such roll sheets. So designers had to go for a compromise. The fuselage had a sheet thickness of 0.8 to 1.8 mm depending on the strength. A similar conflict had arisen with the wires. When the cross-section B-29 wires was transferred to metric, it produced absurd scales: 0.88; 1.93; 3.05; 5.15; 8.8; 13.0; 21.0; 41.0 mm 2. An attempt to use the "next" section failed. If the "plus" was rounded up, weight or power supply increased by 8-10%. If the minus sign was taken, the voltage dropped. Having lost a lot of time on the controversy, cable plant just copied the American sections.

However, the Soviets decided not to attempt to copy the American engine, and instead equipped the bomber with the Soviet ASH-73TK engine designed by A.D. Shvetsov. Even before the war, the American firm Wright and Motostroitel'nym OKB-19 A.D.Shvetsov had a license agreement. For example, the M-71 engine for fighter and Polikarpov-185 was close to the Wright R-3350 engines "Duplex Cyclone" used on the B-29. In addition, the firm had the Wright engines for United States in inch measurement, and for Europe, where they were widely used in metric. No changes had been put into production units, for which our industry had lagged General Electric turbochargers — with their carburetors, magnetos, heat-resistant electric multi-turn bearings. This engine retained the B-29's original turbocompressor and the magnet and heat-resistant bearings.

The B-29 had a shortwave radio station of obsolete design. At the same time, the lend-lease bombers from the Americans were the latest VHF stations. It was decided on the Tu-4 to use latter.

The greatest complexity in the system for remote control of small defensive weapons were computers that determine the parallax. The "American" system had five turrets: four remote-controlled turelâh stood two 12.7-mm machine gun at the rear, in addition to the two machine guns, was a gun. Any combination of these units could manage by five gunners from their seats. The distance from the nose to the stern guns was close to 30 meters, the shooting was carried out at a distance of 300-400 meters, so the distance between the shooter and the gun could be approximately 10% of the distance from the gun to the target. Such conditions forced taking into account the parallax. Computing machines immediately injected an amendment to it, when one of the gunners took control of shooting of a few turrets. Rifle scopes had been conventional collimeters. Development of the drive became one of the biggest challenges for the Soviet industry when copying the aircraft. Subsequently, such systems have long been used in all major Soviet bombers. The Soviet bomber also carried improved gun turrets of Soviet design.

The resulting Soviet airplane was designated the Tu-4.

The TU-4 was so similar to the American B-29 that some worried that if an attack was made, the Russians might put U.S. markings on their bombers to confuse the defenses. A joke among American Air Defense Command [ADC] pilots was that if one went up to identify a B-29-type bomber, identification could be made by looking in the window. If someone in there was pouring coffee out of a thermos, the bomber was American, but if he was pouring tea out of a samovar, it was Russian.

Two reliable genres - submarine adventure and the threat of World War III - came together in director (and co-writer) Samuel Fuller's Hell and High Water, a 1954 film that remains surprisingly relevant more than half a century later. Before the credits, an off-screen voice-over narrates: "In the summer of 1953, it was announced that an atomic bomb of foreign origin had been exploded somewhere outside of the United States. Shortly thereafter it was indicated that this atomic reaction, according to scientific reports, originated in a remote area in North Pacific waters, somewhere between the northern tip of the Japanese Islands and the Arctic Circle."

The plot, involving the Chinese's dastardly plan to incite a nuclear conflagration and blame the US, is soemwhat preposterous, yet believable during the Cold War years of the mid-1950s. A secret Chinese Communist base in the Arctic would launch a false flag nuclear attack on on either Korea or Manchuria with an American with a B-29 that would be attributed to the US and ignite a world war. There were exciting moments like the shooting down of the false flag bomber - and the resulting nuclear detonation. Substituting North Korea or Iran for China, the notion of a rogue nation with atomic capabilities is no less timely now than then.

Around the TU-4 arose a lot of myths, for example, that this is an absolutely exact copy of the B-29, right up to the scratches on one of the wings from the anti-aircraft fire. In fact, this is not so.