Known-7 Soukhoï

The Soukhoï Known-7 (Code NATO " Fitter A") is a fighter-bomber with sweptback wings designed by the the USSR during the years 1950. It was built with more than 1800 specimens used by ten different countries.

The Known-7 is very close to the Soukhoï Known-9 which lays out him of a Delta wing. At the end of the years 1960, Known-7 the Soukhoï Known-17 with variable Géométrie was improved to give rise to.

Design

Known-7 Soukhoï is resulting from the same request as that which led to MIG-21. Emitted in August 1953, this request related to a Fighter plan Supersonique with either a sweptback wing or a Delta wing. The research department of Soukhoï proposed two projects of each type:

the T-1 and T-3 with delta wing, which ended in the Soukhoï Known-9
S-1 and S-3 with sweptback wings

It is S-1 which was retained and gave rise to Known-7. It had a wing with an arrow of 60°, a frontal air intake with an adjustable cone, and was to receive new engine AL-7F of approximately 10 tons of push.

A first prototype made its inaugural flight on September 7th, 1955, with a provisional version without Postcombustion of the engine. In January 1956, a first series of tests was finished and engine AL-7F final installed. Put in competition with the future MIG-21, Known-7 was in advance in its development and took down a first order, after having shown its capacity to reach the speed of 2070 km/h. The planes of preproduction were tested of September 1956 at the end of 1958. Engine AL-7F proved not very reliable, consequently it was decided to install an improved version AL-7F-1 on the production aircraft. After some other modifications, the deliveries with the operational units started during the summer 1959.

Meanwhile, the Soviet air force had emitted a new request for a Avion of attack on the ground, and Soukhoï had proposed a version modified of Known-7. The principal changes were a reinforcement of the structure of the plane and landing gear. A prototype indicated C22-1 made its first flight in March 1959 with an engine AL-7F, and at the end of April with an engine AL-7F-1. After a series of tests, the series production was launched and the first specimens delivered during the summer 1960. The plane was declared operational in January 1962.

These first Known-7 had an autonomy very limited, and Soukhoï worked to solve this problem. A S22 prototype appeared in 1961, with fuel tanks in the wings and of the pylons of carrying modified to make it possible to install external reservoirs. A little later, of the additional modifications were done to carry more fuel in the fuselage and to improve the Avionique. Indicated Known-7BM, this new version entered in service in 1963 and was the first with being exported (Poland and Czechoslovakia). It was followed in 1967 by Known-7BMK intended for export, with a degraded Avionique, whose seven countries became purchasers.

Soukhoï then attacked the other defect of Known-7: the important length of track which it needed (2400 meters for a takeoff with full load). A system of blowing of the shutters was tested, but did not make sufficient improvement. The finally adopted solution was the addition of a rocket with powder to improve acceleration at the time of takeoff, and the installation of two parachutes for braking. In parallel, tests were carried out with a landing gear equipped with a kind of skis, allowing the use of not prepared grounds. This led to the version Known-7BKL, put in production as from 1965.

First flight of a two-seater version intended for the drive take place on October 25th, 1965, and the series production started as of next May. Indicated Known-7U (Code NATO " Moujik"), this version was also declined in version of export.

Alternatives

Known-7 Fitter a: first version of series (20 specimens)
Known-7B: version intended for the attack on the ground (431 specimens)
Known-7BM: version with increased capacity by carburizing (290 specimens)
Known-7BMK: version intended for export (441 specimens)
Known-7BKL: version able to use not prepared grounds (267 specimens)
Known-7U Mujik: two-seater version for the drive (367 specimens)
Known-7UMK: two-seater version intended for export (44 specimens)

Users

Engagements

War the six day old (1967)
Third indo-Pakistani War (1971), with 19 planes lost by India
War of Kippour (1973)

See too

Internal bonds

Soukhoï Known-9
Soukhoï Known-17

External bonds

Known-7 about the official site of its manufacturer
Known-7 about Air Vectors
Known-7 in the Indian air force

Random links: