In 1933 A. N. Tupolev proposed to make the Soviet analogue of “Martin”. He undertook this task, but decided it differently. His ANT-40 in no way resembled an American bomber. For maximum speed the fuselage is very compressed, completely abandoned corrugated cladding and outer charms of bombs.
The first prototype of the American motors “Cyclone” took off on 7 October 1934 But more successful was the second, with a French engine Hispano-Suiza 12Y (we – M-100) up in the air 30 Dec. It has launched since the end of 1935, under the name of SB.
Next the car was built two factories in Moscow and Irkutsk, to the spring of 1941, Bomber repeatedly modernized. He was released with motors M-100, M-103, M-104 and M-105 capacity from 750 to 1,050 HP Total produced 6831 instance. The machine was shipped to Spain, China and Czechoslovakia.
In combat units of the red army air force SB was operated from may 1936 to October it was used in the civil war in Spain, from November 1937 – Sino-Japanese war. Later, SB was used in the fighting at Khasan and Khalkhin Gol, in the war with Finland, the great Patriotic war (up to late 1943).
Data SB 257-series. Scope – of 20.33 m, length is 12.4 m. the Maximum take – off weight 6450 kg Maximum speed – 430 km/h, practical ceiling – 9700 m range -1200 km Armament four 7.62 mm machine guns, bomb load up to 1000 kg.