This was one of the attempts to modify the I-16 into a Shturmovik attacker. Two batteries of three unsynchronized .30 cal ShKAS machine guns were placed in the wing. Four 110 lb bombs could be carried as well.

VTOL Slider - Movable .30 cal ShKAS machine guns

History:
In 1936, during the production of the Type 5, the engineers of Factory No.21 of Nizhny Novgorod A. A. Borovkov and I. F. Florov developed a new version of the I-16 with ground attack capability. The prototype of this variant received the numbering 9211 (Type 9 Factory 21, Issue No. 1). It was also generally referred to as I-16 Shturmovik or I-16Sh (there were other I-16Sh prototypes). The new model was basically similar to the Type 5 with the M-25 radial engine and was basically differentiated by its original armament consisting of two batteries of three ShKAS machine guns located in the center wing with the ability to turn downwards by 9º to allow the beating of ground targets. Another distinguishing feature was the fixed landing gear with two large trouser-type fairings. This arrangement allowed to use the entire lower area of ??the wing center section to place supports for six bombs of 55 lbs, or four bombs of 110 lbs. The set-up of the machine gun rotation mechanism and the timing of the salvo took quite some time. For this reason the first flight of I-16 No.9211 would be made only for December 27, 1937. In 1938, this model of the I-16 would be tested in the polygon of aviation armament tests, motivating a great interest due to the need of the VVS in an attack aircraft. Unfortunately, its developers would soon abandon Factory No.21 to dedicate themselves to the construction of their own model Borovkov-Florov I-207 after they were assigned a productive base of their own and the attack version of the Polikarpov fighter would fall into oblivion.

Photo of the prototype I-16 No.9211 during the factory tests in the autumn of 1937.