Sukhoi's team produced the ANT-31, a low-wing monoplane with an unbraced cantilever wing, retractable undercarriage, an enclosed cockpit and heavy cannon armament.

The mainwheels of the conventional landing gear retracted backwards into the wing, being operated by cables driven by a handwheel turned by the pilot.

The first prototype was powered by an imported 433 kW (580 hp) Bristol Mercury radial engine enclosed by an NACA cowling and driving a two-bladed wooden propeller.

[3][4] It was therefore decided to build a second prototype, the I-14bis (also known as the ANT-31bis and the I-142 with a more powerful (531 kW (712 kp) Wright Cyclone engine, also imported, an uncorrugated wing and a new undercarriage.

The I-14bis demonstrated excellent performance, although handling was still difficult, and an order was placed for production of 55 aircraft, to be powered by the Shvetsov M-25, a licensed version of the Cyclone, with an armament of two 45 mm (1.8 in) Kurchevsky APK-11 recoilless cannons and two ShKAS machine guns.