Ok, here's yet another by-product of Polish Wings. These planes were used for training of Polish pilots in the Soviet Union, but I found no photographs or pictures of those particular planes nor even from that particular flight school, so it would be rather hard to include them in a manner typical to Polish Wings format. I was thinking to drop it altogether, but since I have gathered sources etc. I decided to do it anyway.
Polikarpov R-5 was the mainstay of the Soviet air force in the 1930, used in light bomber, attack, reconnaissance and advanced training roles, as well as in Aeroflot for transport duties and by air branch of Glavsevmorput (later Polar Aviation) in the Arctic service. Besides the basic combat models (which included R-5T torpedo-bomber and MR-5 seaplane) it was used as testbed for various engines and other devices, and produced (or converted) into more specialized versions, including P-5 civil aircraft, PL-5 with enclosed limousine cabin, LP-5 and ARK-5 arctic models. Additionaly Aram Rafelyants designed a passenger version PR-5 with new fuselage that was also produced in respectable numbers (over 200), culminating in prototype of a monoplane variant in 1938. In mid-1930s a heavily-redesigned (in the end giving practically new aircraft) attack version was introduced as R-Z - and later also used as testbed and in civilian purposes. Total production run was over 7000 for R-5 and additional 1000 for R-Z.
Russia, Polikarpov R-5 and SSS and P-5 and PL-5 and LP-5 and ARK-5 (Spain, China, Finland, Persia - Iran, Turkey)
Russia, Polikarpov R-Z (Spain, China)
Russia, Polikarpov PR-5
Russia, Polikarpov PR-12