I've been interested in WW2 era history and equipment, particularly aircraft, armoured vehicles and weapons for well over 5 decades so when I discover something totally new it's a surprise.
Up until two days ago, I had not known about the Kharkiv R-10 ( sometimes known as the Kharkiv KhAI-5 and sometimes as the Neman R-10). Usually, if something like this happens it's because they were produced on a very limited basis but there were around 500 R-10's built and that is not a trifling number. Their first combat use was at Khalkhin Go and they were used to at least the end of 1943.
They are in the game now as fighter bombers and recce aircraft and in game terms for 1939 are the most modern UC 44 aircraft in the Russian OOB.
Just saying because this long after WW2 it's remarkable to find something "new"