The Polikarpov I-15 was a Soviet biplane fighter aircraft of the 1930s. Nicknamed Chaika because of its gulled upper wings it was operated in large numbers by the Soviet Air Force and together with the Polikarpov I-16 monoplane was one of the standard fighters of the Spanish Republicans during the Spanish Civil War where it was called Chato (snub-nose) in the Republican Air Force or Curtiss (because its resemblance to Curtiss F9C Sparrowhawk) in the Nationalist Air Force.
Made by Polikarpov.
It is the successor of the Polikarpov I-5 ,
Polikarpov I-15 is the predecessor of the Polikarpov I-153.