I-1, First Soviet Monoplane Fighter

I-1 (IL-400b) was the first fighter created in the USSR and the first airplane designed by N. N. Polikarpov. The unusual distinctive feature of IL-400 in twenties was the cantilever monoplane wing design.

The second prototype, named IL-400b, made its maiden flight July 18, 1924. During 1926-1927 12 serial fighters I-1 have commissioned.