The Tupolev ANT-7, known by the VVS as the Tupolev R-6, was a reconnaissance aircraft and escort fighter of the Soviet Union. The R-6 traces its roots back to early 1928 when the Soviet Air Force needed a long-range multirole aircraft. The requirements were that it could be used for long-range transport, defensive patrolling, reconnaissance, light bombing and torpedo attack.
Design and development
Under Ivan Pogosski and guided by Andrei Tupolev, TsAGI developed the ANT-7 from the Tupolev TB-1 by scaling it down by about one third. Power for the ANT-7 was intended to be provided by two – Hispano Suiza engines or Bristol Jupiter engines, but the prototype was powered by two – BMW VI engines. The first flight of the ANT-7 took place on 11 September 1929, piloted by Mikhail Gromov. Flight tests started in March 1930 after TsAGi decided to postpone them until after the winter. That summer, the NII-VVS conducted state tests which revealed tailplane buffeting, which was alleviated by fitting enlarged elevators. The next flight encountered radiator damage and an engine failure, but in spite of this, the ANT-7 passed the state acceptance tests.
Operational history
Production aircraft were designated R-6 by the Soviet Air Force. The first production aircraft was rolled off the GAZ-22,, assembly line in November 1931, a year after production started. Another 410 aircraft were made during the following three years: 385 at GAZ-22 in Moscow, five at GAZ-31 in Taganrog, and 20 more at GAZ-12 in Komsomolsk-on-Amur. The standard aircraft crew consisted of the pilot, gunner and observer and the aircraft was able to carry of bombs to a distance of up to. Some were built with floats as the MP-6,, for maritime patrol duties. Another variant was the KR-6, which had two PV-2 machine guns and a second gunner, that was later relegated to training duties. By 1935, the R-6 was becoming obsolete, and several were transferred to Aeroflot and Avia Arktika, which used them to carry passengers and cargo in Siberia before the Great Patriotic War, designated PS-7-2M17, or as MP-6-2M17 if floats were attached.
Variants
Data from: The Osprey Encyclopedia of Russian Aircraft 1875–1995 ;ANT-7:The OKB designation of the project and prototype, powered by two BMW VI V-12 engines. ;R-6: reconnaissance version, powered by two Mikulin M-17F V-12 engines. first flight 1929, trials 1930. ;KR-6: escort fighter version 1934, powered by two Mikulin M-17 V-12 engines, fitted with two PV-2 machine guns and a second gunner. ;KR-6P:Alternative designation of the MR-6 floatplane version. ;MP-6 2M-17: Civil floatplane version, powered by two Mikulin M-17 V-12 engines.. ;PS-7 2M-17: Civil transport version PS-7 2M-17, cargo and passenger transport, first versions open cockpit, one version enclosed. ;MR-6: R-6, torpedo bomber version, 1932. ;P-6: Civil cargo and passenger transport version. ;R-6 Limuzin:Nine-seat civil transport version with a closed cockpit and a seven-seat cabin with glass windows and a luggage compartment. Powered by two BMW VI V-12 engines. First flown in July 1933, the sole R-6L crashed on 5 September 1933 as a result of a maintenance error. ;ANT-18:Ground attack version with two Mikulin M-34 engines, armor protection, and two dorsally-mounted machine guns.
June 23, 1941: A Dalstroi Aviation PS-7 crashed on takeoff from Chokurdakh after the left float struck a submerged log; all five on board survived, but the aircraft was written off.
October 19, 1943: A Dalstroi Aviation PS-7 crashed on takeoff from Zyryanka owing to improper luggage loading caused by crew error; all 12 on board survived, but the aircraft was written off.