This plane, believed to be the first prototype DIT-1, was described as white with red markings, and red stars of plain type on the upper and lower wings and on the rudder.

image from Polikarpov biplane fighter, red stars, Gordon and Dexter

Again, the DIT-1.

image from Polikarpov biplane fighter, red stars, Gordon and Dexter

Here we can see the red star on the upper surface of the wing.

Below: a profile of DIT-1.

image from Polikarpov biplane fighter, red stars, Gordon and Dexter

This plane was probably the second prototype, DIT-2. The shape and the shade of the painting on the nose and on the wheel fairings are well different, lighter than the red of the star on the rudder, and could be medium blue.

image from Polikarpov biplane fighter, red stars, Gordon and Dexter

Front view of DIT-2

Image from Polikarpow i-15bis of Maslov, Wydawnictwo Militaria 199

Rear view, probably of DIT-2.

image from Polikarpov biplane fighter, red stars, Gordon and Dexter

A detail of the cockpits of DIT-1.

Image from Polikarpow i-15bis of Maslov, Wydawnictwo Militaria 199

The front windshield and aiming device.

Image from Polikarpow i-15bis of Maslov, Wydawnictwo Militaria 199

Note the handgrips on the upper wing.

The slots at the root of the wing consoles are usually covered by metal plates.

Image from Polikarpow i-15bis of Maslov, Wydawnictwo Militaria 199

The front cockpit. Note the wiring passing through the windshield and in front of the instrument panel.

Image from Polikarpow i-15bis of Maslov, Wydawnictwo Militaria 199