The Polikarpov I-15 is a mixed Soviet single-engine fighter with a classic tail, a biplane with an upper wing in the seagull arrangement. The prototype's flight took place in 1933. The I-15 is a far-reaching modification to the design of the I-5 aircraft. The first machines of this type were still equipped with M22 engines with a capacity of 480HP, but later models were equipped with British Cyclone engines with a capacity of 715HP, and from 1936. The I-15 was equipped with M25 engines of the same power. I-15 planes fought in Manchuria against Japan and were delivered to China. In clashes with Japanese biplanes, it equaled them in performance, but was rather lost in combat, e.g. with the Ki-27. The I-15 was also used in the Spanish Civil War, where it proved to be one of the best biplanes of the time. However, with the large-scale introduction of monoplane aircraft, the I-15 became obsolete. By the end of 1942, all aircraft of this type were transferred to the USSR to secondary tasks. Technical data: length: 6.1 m, wingspan: 9.75 m, height: 2.2 m, maximum speed: 350 km / h, speed of climb: 7.6 m / s, practical ceiling: 7250 m, maximum range: 530 km, armament: fixed - 2 machine guns BS caliber 12.7 mm, suspended - up to 100 kg of bombs.