Weapons of World War Two
In 1925, the Soviet military authorities decided to request to the industry a bomber of notably advanced characteristics for its time. For example, it was requested that the aircraft were able to transport 5000 kilograms of bombs and that it were armed in such a way that it could fly without a fighter escort. Logically, also the operational range should be notable. Considering that the Soviet aviation was in full phase of reorganization and that the industry still had not fully recovered from the hard hits received during the Revolution, it can be understood the difficulties that projectists and technicians found.
Because of this was directly sought Andrei Nikolaievich Tupolev, an engineer who already had achieved prestige with his creations and who seemingly had an inclination towards large aircraft. Indeed, Tupolev would remain always at the level of his fame by projecting a family of gigantic aircraft that would go from the ANT 14 of 1931, a penta-engined transport aircraft, to the modern multi-jet bombers built during the 1960s. The realization of his project, given the difficulties that Russia was suffering, required a certain time, and in the prototype could not be used only components of national production (as, for example, the engines, initially the American Curtiss, later replaced by the BMW produced in Russia under license).
Finally, the first ANT 6 (first denomination of the TB 3) could fly the 22nd December 1930. Its optimal characteristics made that the aircraft were promptly accepted, and the serial production was started as soon as possible. Indeed, the TB 3 was, for the time on which it was devised and built, an excellent aircraft. For its realization, Tupolev was inspired by some projects that the Germans were elaborating in the worshops Junkers located near Moscow after a German-Soviet agreement. Traces of this relation with Junkers can be found in many details of the aircraft, particularly the coating of corrugated sheet.
The TB 3 was a gigantic four-engined aircraft with almost 40 meters in wingspan. Of entirely metallic construction, with low wing and fixed landing gear, it had the cockpit made the old style, open. The defensive armament, which originally comprised ten 7.62-millimeter machine guns in five positions, was later reduced to six and finally three machine guns, adopting in this version only three positions, as seen in the illustration. The structure of the aircraft, exceptionally robust and easy for maintenance, allowed the crew even to reach the interior of the wings during flight, passing from the fuselage to reach for the outer engines, to effectuate controls or repair small malfunctions.
Over time the formula of the TB 3 logically felt outdated, and it was tried several times to update it, but at the outbreak of the war it had fallen irremediably obsolete. However, in the first days these aircraft effectuated some isolated night bombings over Berlin, to be later wisely relegated to the role of transporting materials and paratroopers, and so they operated during the war.
As a curiosity it can be mentioned that it was elaborated as well an "aircraft carrier" version of the TB 3, able to transport up to five aircraft (two biplane fighters I 15 over the wings and three monoplanes I 16, two under the wings and one under the landing gear). But during the war some TB 3 transported two SPB (I 16 dive bombers) under the wings to the vicinity of the target. Arrived there, the aircraft were detached and once effectuated the bombing they took altitude again and returned to base escorting the "mother aircraft". With a version of this type was how it ended in August 1941 the operative life in the frontline of this undoubtedly well achieved aircraft.
First flight: 22 December 1930
Wingspan: 39.50 meters (Model 1932); 40.50 meters (Model 1934 and Model 1935)
Wing area: 250 square meters
Length: 24.40 meters (Model 1932); 25.20 meters (Model 1934 and Model 1935)
Height: 8.45 meters
Full load/Empty weight: 18000/10000 kilograms (Model 1932); 17500/ kilograms (Model 1934); 15180/ kilograms (Model 1935)
Payload/Crew: 8000 kilograms/7 (Model 1932); /5 (Model 1934); /5 (Model 1935)
Engines: Four Mikulin AM 17F of 680 horsepower (Model 1932); four Mikulin AM 34R of 830 horsepower (Model 1934); four Mikulin AM 34RN of 1050 horsepower (Model 1935)
Cruising speed: 160 kilometers/hour (Model 1932); 200 kilometers/hour (Model 1934); 257 kilometers/hour (Model 1935)
Maximum speed: 230 kilometers/hour (Model 1932); 250 kilometers/hour (Model 1934); 320 kilometers/hour (Model 1935)
Service ceiling: 3800 meters (Model 1932); 5000 meters (Model 1934); 10000 meters (Model 1935)
Defensive armament: Ten Degtyarev 7.62-millimeter machine guns (Model 1932); six Degtyarev 7.62-millimeter machine guns (Model 1934); three ShKAS 7.62-millimeter machine guns (Model 1935)
Drop armament: 1500 kilograms of bombs (Model 1932); 1000 kilograms of bombs (a) (Model 1934); 1500 kilograms of bombs (a) (Model 1935)
Operational range: 2000 kilometers (Model 1932 and Model 1934); 1680 kilometers (Model 1935)
(a) With possibility of overload for short travels
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