Kocherigin BSh-1

At the end of 1935, the USSR received information about the American light bomber and attack aircraft Vultee V-11. Under orders of the People's Commissar of Defence Kliment E. Voroshilov showed interest on the project in order to replace the outdated Soviet attack biplanes like the Polikarpov R-5Sh.
Therefore, the Vultee V-11 was included in the list of purchase licenses and, on 11th April 1935 negotiations with Vultee began.
Both Soviets and Vultee reached an agreement and four Vultee V-11GB were sold to the USSR together with production blueprints adapted to the metric system. These weren't the standard type as they had a crew of three, one pilot, a rear-gunner and one navigator-bombardier.
It was powered by a single Shvetsov ASh-62 rated at 1000hp (746Kw) radial engine and was armed with four forward firing 7.92mm ShKas machine guns mounted in the wings with 3600 rounds in total. It could also carry up to 400Kg (881lb) of ordnance under the fuselage. As defensive armament, it had one 7.92mm Shkas at the end of the canopy and another one that was deployed on a hatch ventrally placed just behind the one at the of the canopy.
The first Kocherigin BSh-1 rolled out of the factory on 11th December 1936 and it was tested so it wasn't until mid 1937 that it entered into production. It was found however that the armour fitted for the ground attack role, reduced performance greatly and it was decided to stop production after only 31 aircraft were manufactured. As they proved to be not suitable for service in the VVS (Soviet Air Force) they were transferred to Aeroflot, which redesignated them as Kocherigin PS-43 and used them as high-speed transports until June 1941 when Germany invaded. Then they were transferred both to the VVS and PVO (Soviet Air Defence).
They served all-through World War 2 and, albeit serving in small numbers, they were present at the Battle of Stalingrad as they were the ones, together with outdated Polikarpov R-5, that delivered air mail to the sieged troops. However, casualties were heavy and by 1st June 1944 there were only 9 of them active and by the end of that year, 8 serving with the 1st Baltic Front and 2nd and 3rd Byelorussian fronts as par of the 3rd Communications Division air unit. By the beginning of 1945 as the lend-leased Douglas A-20 and B-25 were somewhat outdated, they were sent to the 3rd Communications Division to serve in the liaison role so the extremely worn-out and old PS-43 were written-off. By September there weren't any Kocherigin BSh-1 or PS-43 active inside the USSR.
Finally we decided that this aircraft would fit perfectly in an alternate history universe where the Whites won the Russian civil war, so we decided to paint one of them in Russian Aeronaval colours.

Sources:
1. https://en.wikipedia.org/wiki/Vultee_V-11
2. http://www.airwar.ru/enc/aww2/bsh1.html (translated)