Polikarpov 2I-N1 (DI-1)

The first two-seat fighter of indigenous Soviet design, the 2I-N1 (the designation signifying Dvukhmyestny istrebitel, or two-seat fighter, with one Napier engine) was a single-bay unequal-span biplane of wooden construction with a monocoque fuselage and a 450hp Napier Lion water-cooled engine. The sole prototype of the 2I-N1 (also referred to as the DI-1) was flown on 12 January 1926, and demonstrated a performance higher than that of contemporary single-seat fighters. Armament comprised one fixed 7.62mm gun and a similar calibre weapon on a ring mount in the rear cockpit. On 31 March 1926, high speed tests during the ninth flight terminated with the destruction of the aircraft as a result of a structural failure, no further development being undertaken.

3-View

A three-view drawing (1280 x 922)