Copyright© 1999, Douglas Alberg.   Photographed July, 1999
The United States provided Russia with medium bombers, fighters and transports under the Lend-Lease Act during World War II, but would not provide heavy bombers. The Soviets had very little heavy bomber capabilities and no near-term prospects of developing a modern four-engine bomber.
Since the Soviet Union was not at war with Japan until August, 1945, they confiscated all American aircraft that made emergency landings in Russia prior to that time. The first aircraft to be seized was a B-25 that flew in the Doolittle raid on Tokyo in April, 1942. A total of three B-29's were confiscated, all in 1944:
On July 29, 1944 Ramp Tramp, a B-29-5-BW serial number 42-6256, was unable to return to its base after a raid in Manchuria and landed in Vladivostok.
On November 11, 1944 The General H.H. Arnold Special, serial number 42-6365, was damaged during a raid against Omura on Kyushu was forced to divert to Vladivostok
On November 21, 1944 Ding How, serial number 42-6358, also landed in Vladivostok.
In January, 1945 the crews of these aircraft were quietly returned to the U.S. via Teheran, but their aircraft stayed behind.
After flight tests of Ramp Tramp, Stalin launched a program to exactly duplicate the B-29 on June 22, 1945. The aircraft was initially called B-4, but was soon renamed Tu-4 after Andrei Tupolev became manager of the project.
Though the order was to produce an exact copy, there were practical difficulties in doing this. In the end, several concessions were made to enable the use of Soviet designs. These included the use of Soviet NS-23 canons instead of American .50-caliber machine guns. Shvetsov ASh-73TK engines replaced the original 2,200HP Wright R-3350 engines. These were a soviet copy of earlier Wright engine designs that had been acquired under license from the U.S. They were supposed to have slightly greater horsepower, but initial versions did not perform as well as the R-3350.
In order to appear to comply with Stalin's orders, Tupolev ensured that obvious features of the Tu-4, such as the interior paint scheme, were identical to the B-29. Even a repair patch was duplicated from the original B-29. In less obvious ways, the aircraft was different. For example, the Tu-4 used metric units, as machinery used to manufacture components and materials were calibrated to metric units. Since the B-29's 1/16" aluminum skin would have required an impractical 1.5875 millimeter thickness in order to be an exact duplicate, a skin of varying thickness between .8 and 1.8 millimeters was used instead.
The General H.H. Arnold Special was disassembled at the Central Aerodrome in Moscow. Ding How was grounded as a reference aircraft and Ramp Tramp remained flyable. Ramp Tramp's engines were replaced with ASh-73TK's to make the aircraft more maintainable and it remained in-service for nine years.
Each of the B-29's 105,000 components had to be reverse-engineered by various design bureaus in Russia. There was difficulty producing the large tires and landing gear, so agents were sent to the West to purchase them on the surplus market. In the end, the Tu-4 was only one percent heavier than the B-29.
When disassembling the General H.H. Arnold Special, a plaque next to the bombardier's seat was found. It said:
The first Tu-4's were produced on-schedule in 1947, less than two years after the project began. Its maiden flight was in May, 1947 and its first public display was on Aviation Day in August, 1947. Western visitors who saw the Aviation Day demonstration became aware of the Tu-4 at this time.
Tu-4 had many problems initially (as did B-29's), but these were resolved over the years. The Tu-4 become operational in 1948. In the early 1950's, a number of Tu-4's were sent to China. A total of 845 Tu-4's were produced.
In May, 1947 Ramp Tramp was the mother ship to the rocket-powered Samolet 346. This was the product of a German experimental project called DFS 346. The Soviets reportedly captured the DFS 346 in 1945 and built the Samolet 346 using German scientists and a German test pilot.
On October 18, 1951, a Tu-4 dropped the first Soviet atomic bomb to be delivered by air.
Several variants of the Tu-4 were made. An experimental tanker was developed in 1952. An experimental low-wing passenger version of the Tu-4 named the Tu-70 was also built and flown but never saw production.
The Chinese replaced the engines with turboprops and created their own variants, including an early warning and electronic countermeasure aircraft and a craft for launching drones. These were reportedly in-use as late as 1968. An example of each of these two aircraft is on display at the Chinese Aviation Museum outside of Beijing.
By 1954, Tu-4's were beginning to be removed from military service and the Ramp Tramp was scrapped this year. The Tu-4 at Monino is the most original remaining example. The two turboprop Tu-4's in China are the only other known examples on display that I am aware of.