Boeing’s B-17 was the most numerous heavy bomber of World War II, and its reputation of being nigh indestructible in the face of Messerschmidts and flak cannons is stuff of legend. The first flight of the B-17 was in 1935, and a decade later at the close of World War II, the B-17 would begin to show its age. It could only carry 6,000 pounds of ordnance; the first atomic bombs, Little Boy and Fat Man, weighed 9,700 pounds and 10,300 pounds, respectively. The Avro Lancaster notwithstanding, a new aircraft would be needed for the Allied invasion of Japan. This aircraft would be the Boeing B-29 Superfortress.
On paper, the B-29 nearly holds its own against all but the most modern bombers of aviation history. Yes, the B-29 is slow, but that’s only because jet engines were in their infancy in 1944. This bomber was a forgotten super weapon of World War II, and everyone – Japan, German, Great Britain and the USSR – wanted their own. Only the Soviets would go as far to build their own B-29, reverse engineering the technology from crashed and ditched American bombers.
Like all countries in World War II, the Soviets needed a heavy bomber. Flying from Moscow to Berlin was a mere 1,000 miles, Vladivostok to Tokyo is only 700 miles. Russia did not need a long-range bomber as much as they needed a bomber that could carry more than a dozen 500 pound bombs.
At the outset of the war, the Soviet Air Forces’ most powerful bomber would be outmatched by any other four-engine bomber in the Allied inventory. The Petlyakov Pe-8 could carry 2,000 pounds of bombs 1,200 miles. the B-17 could carry 6,000 pounds the same distance. The Soviets were outclassed, and even though Berlin is less than a thousand miles from Moscow, and Tokyo is seven hundred miles from Vladivostok, a larger bomber would eventually be needed.
Raids on Tokyo
The US had hit Tokyo early in the war, in April 1942 during the Doolittle Raid, but the success of this operation was marginal. The operation included carrier-launching B-25 bombers to overfly Japan and land in China. For the planes, it was a one-way trip. Little damage was done and after the mission, Lieutenant Colonel James H. Doolittle believed he would be court marshaled on his return to the states. It was only because of the massive morale boost that the Doolittle raid could be called a success.
The Doolittle would never be duplicated, and it would take another two years before the next attack on Japan. In the summer of 1944, the US Army Air Forces launched Operation Matterhorn, bombing raids from air bases deep in China’s interior to Japanese-controlled Manchuria, Formosa, and the Japanese home island of Kyushu. While this operation would not be a resounding success – the logistics of moving fuel and bombs from bases in India to forward air bases in China would be a nightmare – it did provide the Soviets with several B-29 airframes to study.
Recovering the B-29
Although the Soviet Union was an ally, the United States refused to provide the B-29 under the a lend-lease agreement. That’s not to say the United States was unwilling to provide aircraft to the Soviets; the American-designed P-39 Ariacobra would be best known as a Soviet plane, with thousands ferried over from plants in the United States to Alaska, through Siberia, and over to Europe’s eastern front. The B-29 was special, it was the biggest and most powerful bomber of its day, something every country wanted, and a plane the US would not share.
During the few missions of Operation Matterhorn, several B-29s were damaged and rerouted to Russian territory. One B-29 crashed, with three others making controlled landings. Estimates to build a Soviet-designed long-range heavy bomber were about five years, and there were no plans on the drawing board. To Stalin, the arrival of B-29s on Soviet soil was a gift. The order was given by Stalin to copy the B-29, bolt for bolt, in two years.
A Mechanical Marvel
The B-29 was a mechanical marvel. The remote-controlled gun turrets, Norden bomb sight, pressurized compartments, and extraordinarily powerful engines were the pinnacle of technology in the 1940s. There were other technological advances in the B-29 less apparent to the American workers on B-29 assembly lines. The landing gear for the B-29 was enormous, and this was something Soviet industry could not manufacture. The impressive clear plastic dome on the nose of the B-29 was something the Soviets could not duplicate; test pilots frequently complained the Soviet-manufactured acrylic panels were distorted.
The most advanced bomber in the Soviet inventory used fabric-covered ailerons, while the B-29 was an all-aluminum marvel. Cloning the B-29 would be a nigh-impossible task even in the best of times, and one that would fall directly on the shoulders of Andrei Tupolev, head of the most important Soviet aircraft design bureau on the outskirts of Moscow.
Three aircraft diverted to Siberia during a raid on Japan, and were quickly ferried to the Central Aerodrome in Moscow. These aircraft, General H.H. Arnold Special, Ding How, and Ramp Tramp would be either disassembled, used for training and flight testing, or kept as a reference airframe. The reverse engineering of the B-29 would require over 100,000 components to be remanufactured, and the directive from Stalin required these aircraft to be perfect reproductions. This copy of the B-29 would become known as the Tu-4.
This was easier said than done. The Soviet Union did not have the manufacturing ability to reproduce many parts, and either way, the B-29 used a 1/16″ aluminum skin. The Soviet Union used the metric system. Still, the reproduction was a success. Tupolev’s design team replicated the interior paint scheme, and a repair patch on the General H.H. Arnold Special was reproduced in the cloned aircraft.
The differences between the B-29 and Tu-4 were more than skin deep. The powerful, 2,200 horsepower Wright R-3350 engine found in the B-29 was unavailable. The Tu-4 was fitted with a variant of a clone of this engine, the ASh-73TK that produced 2,300 horsepower. The first version of this engine did not match the performance of the Wright engine. The .50 caliber machine guns used in the B-29 could not be sourced, and the Tu-4 was fitted with cannons. The massive tires from the B-29 could not be manufactured, and agents turned to the western war surplus market to outfit the landing gear of the Tu-4.
Germany fell to the Allied powers on May 8th, 1945, and because of agreements at the Tehran conference, the USSR would enter the war 90 days after Germany fell. On August 6th, the atomic bomb would fall on Hiroshima. On August 9, Nagasaki. Japan would surrender on August 15th, and the Soviet Union would not enter the war in the Pacific. By this time, the B-29 was fully disassembled in a Moscow hangar, although it would be another two years until the latest Soviet bomber would be revealed.
On August 3, 1947, the Soviet Union held Aviation Day at the Tushino airfield northwest of Moscow. Representatives from all major air forces were present. This air show would be the first public viewing of the Su-9 and Su-11, a copy of captured German Messerschmitt Me 262 jet fighters. During the show, three large bombers flew past at 600 feet. The distinctive streamlined shape, four roaring engines, and unique Plexiglas nose told the observers these were the forgotten B-29s lost years earlier. After this fly-by, another bomber, this time a passenger version of the Soviet Tu-4 roared past the crowd. The world now knew the Soviets were flying brand new B-29s.
The B-29 would not see much service after the war; it was quickly eclipsed by the massive B-36 peacemaker, itself eclipsed by the B-52 Stratofortress in 1955. The Tu-4, though, would remain in the Soviet inventory for decades.
Although the mythos surrounding the Tu-4 revolves around it being a carbon copy of the B-29 – down to the alleged inclusion of flak damage on one of the wings – this isn’t truly the case. The Tu-4 served to bootstrap the Soviet aerospace industry, and a mere decade after the introduction of the Tu-4, the Soviet Air Forces introduced The Tu-16, a jet bomber still in service with the Chinese Air Force, and the Tu-95, a turboprop bomber that will remain in service until the 2040s.
It’s an impressive piece of engineering, despite most of the design work being a Boeing product. It’s also not the only time an American design was copied by Soviet aerospace engineers. The Soviet’s first atomic bomb – the RDS-1, a copy of the Fat Man and Gadget devices to come out of Los Alamos – was dropped by a Tu-4.
Now, only one Tu-4 aircraft survives, in an aviation museum on the outskirts of Moscow. While that’s not a remarkable survival rate for a manufacturing run of hundreds, it is an excellent example of how far Stalin would go to bootstrap the Soviet aerospace industry.