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 Soviet B-29, a Tupolev Tu-4 Story |
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 Photograph by John Sloan (JohnS426@aol.com) Tu-4 Soviet Copy of the B-29 by Joe Baugher (Joseph.F.Baugher@att.com) On July 29, 1944, B-29-5-BW serial number 42-6256 commanded by Capt. Howard R. Jarrel was damaged by flak during a raid on the Showa steel works at Anshan in Manchuria. Unable to make the trip back to its base around Chengtu in China, the crew decided to divert to Vladivostok in the Soviet Union. Since the Soviet Union was not at war with Japan at the time, both the aircraft and Capt. Jarrel's crew were interned. On August 20, 1944, during a raid on Yawata staged out of the Chengtu bases, B-29A-1-BN 42-93829 was forced to divert to the Soviet Union. It crashed in the foothills of Sikhote Alin Range east of Khabarovsk after the crew baled out. The crew was interned. On the night of November 10/11, 1944, B-29 42-6365 was damaged during a raid against Omura on Kyushu and was forced to divert to Vladivostok. It was followed on November 21 by 42-6358. Again, both crews and both aircraft were interned. The Soviets were now holding three intact B-29s and four B-29 crews. In January of 1945, it was arranged by the Soviets for these four crews to "escape" to the West via Teheran, but their B-29s remained behind. World War 2 had been over only for a little over a year when an article appeared in the November 11, 1946 issue of the Berlin newspaper Der Kurier claiming that the Soviet Union was manufacturing a bolt-for-bolt copy of the B-29 in a series of factories located in the Urals. [RAP comment: This most likely leaked from German scientists and engineers who were detained in the Soviet Union after WWII] This report was widely disbelieved, since the Soviet Union was at the time thought incapable of manufacturing an aircraft as large and sophisticated as the B-29. However, the report was given more credence when it was revealed that some Soviet agents had been attempting to purchase B-29 tires, wheels, and brake assemblies in the USA. [RAP comment: This could have been for a transport version of the Tu-4, Tu-70] During the August 3, 1947 Aviation Day parade over Tushino Airport, Moscow, three four-engined aircraft which were obviously B-29s appeared during a low-altitude flyover. It was at first thought that these three aircraft might have been the same 3 intact B-29s known to have been in Soviet hands, but a fourth aircraft appeared which was obviously a transport conversion of the B-29, leaving no doubt that the earlier report of B-29 manufacture in the Soviet Union was completely accurate. The transport version was designated Tu-70, but it was only revealed later that the designation of the bomber was Tu-4. During the Great Patriotic War, Josef Stalin had allocated the highest priority to the development of a strategic bombing capability, and the presentation to the Soviet Union of three intact B-29s was extremely fortuitous, since the Soviet aircraft industry could now overcome the immense technological problems involved in the development of a strategic bomber in a fraction of the time it would have taken to develop an indigenous design from scratch. [RAP comment: It is not that USSR have not had experience with large bombers. Sikorskii's Ilya Muromets was first four engined bomber ever build. Tupolev prewar designs (early 30's) such as TB bomber series were revolutionary at the time of introduction. The rest of the world was using biplane bombers when sleek TB was delivered to Red Army air force. ANT-20 Maksim Gorkii was the largest aircraft when it was build and Petlyakov's Pe-8 was on pair with B-17, although only few were build during WWII]. Stalin ordered that the Soviet Union develop a copy of the B-29 for immediate manufacture. The design bureau of Andrie N. Tupolev was given responsibility for the airframe, while the engine bureau headed by Arkadii B. Shvetsov was assigned the responsibility of copying the Wright R-3350 Duplex Cyclone engine. The Soviet version of the B-29 was assigned the designation Tu-4. The Shvetsov version of the Wright Duplex Cyclone was known as the ASh-73TK. Two of the USAAF B-29s were disassembled for detailed evaluation, with the third being kept intact for flight testing. [RAP comment: This remaining B-29 was used for flight tests of DSF-346 rocket plane captured from Germany. DSF was hang under the wing of B-29 and released at high altitutde]. The go-ahead for the program was given before the end of 1944, and the Tu-4 project was well under way by the first quarter of 1945. A factory on the Volga was given the task of building 20 test and evaluation aircraft, and two factories behind the Urals were given the responsibility for full-scale production. In spite of the end of the war, the Soviet Tu-4 program went forward with all deliberate speed. The first Tu-4 test aircraft was ready by the late summer of 1946. Early test flights turned up problems with the electrically-actuated undercarriage which forced several wheels-up landings. In addition, there were frequent runaway propellers. Lots of test pilots complained about the distortion of vision caused by the extensively-glazed nose. [RAP comment: See discussion below]. Following the public debut of the Tu-4 in the Aviation Day parade on August 3, 1947, initial long-range trials began. Many teething problems with both the Tu-4 systems and the Shvetsov ASh-73TK engines still remained to be resolved. The Tu-4 began to enter service with the Soviet strategic bombing arm, the Dal'naya Aviatsiya (DA), in 1948, providing the Voennovosdushniye Sily (V-VS, the Air Forces of the USSR) with true strategic bombing capability. The series production Tu-4s suffered continuously from malfunctions in the remotely-controlled defensive armament system and in the crew cabin pressurization system. The reliability of the ASh-73TK turbosupercharged engines still left a lot to be desired. Quality control at the manufacturing plants had to be tightened up, and by early 1949, most of the more serious defects had been corrected. It was not until mid-1949 that the Tu-4s of the DA had achieved full operational capability. By the end of 1949, some 300 Tu-4s had entered service with the DA. In addition, a few Tu-4s entered service with the Aviatsiya Voenno-Morskovo Flota (AV-MF, the Naval Air Force) as long-range patrol aircraft. The Tu-4 was assigned the code name "Bull" in the NATO code naming system. The entrance into service of the Tu-4 threw the USAF into a virtual panic, since the Tu-4 possessed sufficient range to attack Chicago, Los Angeles, and New York with a worthwhile load on a one-way "suicide" mission. From seized airfields in Iceland, Soviet Tu-4s were even capable of hitting targets in New England, New York, Pennsylvania, and Ohio, and from bases in Greenland they could hit targets as far away as New Orleans or Denver. Since the Soviets now had a weapon capable of attacking North America, this forced the United States government to develop an extremely costly air-interception capability involving ground radar installations, a Ground Observer Corps, radar picket planes, Nike surface-to-air missiles, and a fleet of jet interceptor fighters. The development of the Soviet atomic bomb in 1949 gave the air defense program a new urgency, since the United States was itself now in danger of a nuclear attack. Approximately 1200 Tu-4s are believed to have been built in the Soviet Union, with some going to China during the later 1950s. During the later 1950s, the Tu-4 was progressively withdrawn from operational service with the DA and replaced by more advanced types. These planes were then transferred to the air transport force, the Voenno-Transportnaya Aviatsiya to supplement the short-range Li-2s and Il-14s. As the Antonov An-12 turboprop transport became available, the Tu-4 was progressively withdrawn from the transport role. By the beginning of the 1960s, the Tu-4 was essentially also out of the inventory of the shore-based maritime patrol force. A few Tu-4s had been provided to China to provide that country with at least a token bombing force, and some of these were reportedly still in service in China as recently as 1968. Specification of Tu-4:
From: mark_orr (mark_orr@dgc.ceo.dg.com) I was watching a documentary regarding the first air drop of an A-bomb by the USSR, the airplane they used was a ringer for the B-29. Did they copy the B-29??? Does anyone out there know anything about this??
From: "Emmanuel.Gustin" (gustin@hhipe.uia.ac.be) Yes, they built their own version of it, the Tupolev Tu-4 'Bull'. As pattern aircraft they used a B-29 that had been interned during the war, after an attack on Japan. The USSR was neutral in the conflict between the USA and Japan, so they kept the aircraft. Contrary to what is often thought, the Tu-4 was not an exact copy. They had to reverse-engineer the entire thing for many reasons, from the trivial --- the Soviet industry produced metal plate and screws in metric sizes! --- to the intricate. For example, they were not able to manufacture the integral wing fuel tanks of the B-29, and they used 23mm Nudelman-Suranov cannon for defensive armament.
From: "Dimitriy A. Levin" (dlevin@stega.smoky.org) I've looked through some of the stuff I have on Tu-4 and it's really amuzing to see through how much trouble Tupolev went to make B-29. They had to rescale every single part to metric system. And I don't even want to mention how much fun they'd had with the bolts, nuts, and wires.
From: Simon Shpilfoygel (simon@cs.ucla.edu)
Yeah, that was a major challenge. More funny, the first batch of Tu-4s got custom-ordered parachutes: Soviet parachutes couldn't fit into US-standard seats ( and vice versa ) so the orders [ to copy everything or else ] were followed exactly and both seats and parachutes were copied. The subsequent batches of Tu-4 got standard issue seats and parachutes ...
From: Chris Jamesson Absolutely, they even copied it down to a metal repair plate on the tail.
From: Alexei Gretchikhine (agretch@aeroweb.lucia.it) Yet another urban myth. Few others: The damage from air-defence guns (holes in one of the wing roots) were copied. The scroll tunnel connecting cockpit and rear parts of the bomber was half green and half white, because Boeing run out of one of the color when painting this particular specimen. Tupolev team was thinking of keeping USAAF insignia instead of the red stars. But these are nothing but myths...
From: Chris Douglas (cdouglas@origin.ea.com) Why do you say that? Considering the tyranny of Stalin (arguably the most evil man that has ever lived), and the fear he espoused in his subjects, the motivation for the workers to replicate these artifacts appears to be there. Granted there's likely little specific evidence that it did happen, but what have you heard that makes you certain it didn't?
From: Paul Tomblin (ptomblin@compass.xcski.com) Because your justification for saying that it did happen is that: The first premise I'll dismiss out of hand, because that's the classic defense of somebody who wants to believe an urban legend but doesn't have any evidence. The second premise is absolutely ludicrous. The Soviets had to re-engineer the aircraft to use metric machining, metric fasteners and bolts, their own sized guns and other armaments. They then had to figure out how to manufacture this slightly different B-29 with no reference to how the original was constructed, and make sure that any changes they made were still within reasonable weight and balance and aerodynamic regimes. The Soviets have proven themselves to be absolute geniuses in reverse engineering, both in aircraft and computers. They weren't so bad at doing their own designs either, so they had the expertise to tell the difference between stress relief holes and bullet holes.
From: Bev Clark/Steve Gallacci (bevnsag@netcom.com) Well, they had at least three machines to examine, so individual quirks of one would be canciled out.
From: David J Sherlock (davids@titan.oit.umass.edu) Don't know if this is a myth too but I recall reading somewhere that the Soviets had some problems reproducing the compound curves of the B29's glazed nose. Seems their plexiglass technology wasn't as far ahead as the West's. Can anyone confirm or deny this?
From: Alexei Gretchikhine (agretch@aeroweb.lucia.it) Ever wondered why none of Tu-4 followers had "greenhouse" cockpit? "Superior" design was discarded very soon because crew complained about reflections off the inside glass surfaces of the Tu-4 cockpit. I guess it is very disturbing to spot a what seems like afterburner of the closing interceptor and realize in couple of seconds that it is just a reflection of one of the cockpit lights.
From: Mike Dembinski (mdembinski@delphi.com) 'Viktor Suvorov' (pseudonym) wrote 'The Liberators', a tragi-comedy about his experiences in the WarPac invasion of Czechoslovakia in 1968. While most of the book sticks to incidents and anecdotes highlighting the sheer stupidity/globe-threatening danger of the Soviet military, he includes one chapter (which sits rather uneasily with the rest of the narative) about the Tu-4. I quote selectively: 'The B-29 was dismantled into thousands of the smallest possible parts , which were distributed among the various ministries, departments, desing bureaux and scientific research institutes with the explicit commant to copy each detail, aggregate or device and then to embark upon its mass-production within ten months... Difficulties arose from the very beginning of the copying process. To begin with, the use of the metric system of measuring was quite out of the question...Soviet trade representatives in Canada, England and the USA started to buy up measuring equipment in small quantities in order not to create suspicion. And the retraining of thousands of engineers, technicians and workers, to swtich over to calculating in inches, feet and pounds, began urgently. About the 'urban myths': A little hole was found on the left wing of the [first] aircraft. No aerodynamics or durability expert had he slightest idead what the hell it was there for. There was no tube or wire attached to it, and there was no equivalent to it on the right wing. The opinion of a commission of experts was that the hole had been bored by a factory drill at the same time as the other holes for the rivets. So what to do? Most probably, the hole had been drilled by mistake, and later no one had bothered to fill it in as it was much too small. The chief designer was aked his opinion. 'Do the Amercans have it?' 'Yes.' 'So why the hell are you asking me? Weren't we ordered to make them identical! Alike as two peas?' So, for that reason, a very small hole indeed, made with the thinnest possible drill, appeared on the left wing of all Tu-4 strategic bombers...' Similar tale about the crew tunnel: two thirds was painted chromate green, the aft portion left in white primer. 'Later, this ratio was included in all the instruction books on how to paint the interior of the bomber'. About the stars: 'What kind of stars should be put on the mass-produced aircraft - white American stars of red Soviet ones? If you put white stars, you risk being shot as an enemy of the people. If you put red, first, it will not be a copy, and second maybe Stalin is planning to use the bombers against America, England or China, and therefore keep the American markings.' The question went all the way up to Stalin himself: Beria (NKVD chief, in charge of B-29 duplication project) 'told Stalin about the stars as if it were a funny story and that by the way in which Stalin laughed at the joke, Beria knew unerringly which stars should be used. The last problem was solved and mass-production started...' I'll leave it up to you to judge the credibility of 'Suvorov's' story. The US successfully 'stretched' the B-29 into the B-50, and that stayed in front-line medium bomber duties until replaced by the B-47. The Soviets unsuccessfully stretched the Tu-4 'Bull' into the Tu-85 'Barge'. This had bigger span, stepped nose, longer fuselage, more powerful radial engines but did not attain production status. What eventually did supercede the 'Bull' was the Tu-95 (aka Tu-20) 'Bear'. Further fuselage stretch, swept wings and tail surfaces, contra-rotating turbo-props, but at heart, an American B-29 Superfortress that force-landed in Siberia...
From: Mike Dembinski (mdembinski@delphi.com) First Soviet atom bomb was detonated on 29 August 1949 from a 30m (100 ft) tower 70km south of Semipalatinsk-21. It yielded 20 kilotons Second Soviet atom bomb was also exploded from a tower on 24 September 1951; it was half the weight of the first and yielded 40-50 kilotons. An identical bomb was dropped from a Tu-4 on 18 October 1951; third bomb, first aerial drop. The CIA concluded that this was an airburst. First aerial drop of an H-bomb was not until 22 November 1955, from a Tu-16 (painted white to reflect blast), two years and three months after the first ground-burst H-bomb test. From David Holloway's 'Stalin and the Bomb', 1994, Yale Univ. Press (ISBN 0-300-06056-4) 'The first flight test of the Tu-4 took place in July 1947. The new bomber had a range of 5,100 kilometres with a bomb load of 6-8 metric tonnes and a flight speed of about 550 km/h at 10,000 metres. It was not quite as good a plane as the B-29. Stalin authorised full production in 1948, even though there were still problems to iron out with the design. More than a thousand Tu-4s were built over the next five-six years and some of these were modified to carry atomic bombs. The Tu-4 entered service with the Long-Range Air Force in 1948, but Soviet designers soon realised it was becoming obsolete.' |
