S-37 BIERKUT

The Sukhoi S-47 Berkut is an experimental Russian interceptor with a metal-composite structure and a very rare negative wing slant. The drive is provided by two Soloviev D-30F6 turbojet engines. The prototype flight took place in September 1997. To date, only four copies of this machine have been built. The machine has no fixed armament. Work on the Sukhoi S-47 began in the early 1980s and was aimed at creating a far-reaching modernization of the very successful Su-27 aircraft. After many turbulences and suspensions of the project related to financial problems, the Suchoj company decided to finish the project on its own and in 1999 presented the finished machine. The plane, however, was not intended for mass production, but rather became a technology demonstrator. First of all, the machine is distinguished by the negative skew of the wings, which has many advantages, including: it gives better maneuverability at speeds of about 1 Ma, it also allows to reduce fuel consumption. It also uses new composites, which constitute approx. 15% of the materials from which the S-47 was made. Weapons were placed in the inner chamber, which was also rarely found in other Soviet fighters. A fly-by-wire system was also introduced. Although the S-47 did not enter mass production, it allowed the Sukhoi company to gather valuable experience, which was used in the Su-35 aircraft and in the development of the Russian 5th generation fighter - PAK-FA.