The R-5 was developed by the design bureau lead by Nikolai Nikolaevich Polikarpov as a replacement for the R-1, the copy of the Airco DH.9A which served as the standard reconnaissance and light bomber aircraft with the Soviet Air Force. The prototype first flew in autumn 1928, powered by an imported German BMW VI V-12 engine. It was an unequal span single bay biplane of mainly wooden construction. After extensive evaluation, the R-5 entered production in 1930, powered by Mikulin M-17s, a licence built copy of the BMW-VI, as a reconnaissance bomber. Further modified versions were produced to serve as floatplanes, ground attack aircraft and civil transports.
R-5s were also used by the Spanish Republicans in the Spanish Civil War, 31 being sold to Spain. These arrived in November 1936, and were quickly deployed on combat operations, but were found to be slow and were relegated to night bombing. Seven R-5s remained in good condition in March 1939. The aircraft was known as the "Natasha" in the Republican Air Force.
The R-Z or R-Zet was developed at the aircraft factory GAZ No 1 (State Aircraft Factory No 1) at Moscow as a development of, and a replacement for the Polikarpov R-5, the standard light reconnaissance bomber of the Soviet Air Force. Based on the R-5SSS, the most advanced variant of the R-5, the R-Z had a new, deeper, monocoque fuselage, with a sliding canopy for the pilot and fixed glazed fairing for the observer. The 544 kW (730 hp) M-17F engine (a licenced built copy of the BMW VI was replaced with the 611 kW (820 hp) M-34 engine. The R-Z first flew in January 1935 and was accepted for the Soviet Air Force in preference to the competing Kochyerigin LR, also an R-5 derivative. By the time production finished in spring 1937, 1,031 R-Zs had been built.
Its first use in combat was during the Spanish Civil War, where 61 R-Zs were delivered to the Spanish Republicans from 1937, where they were nicknamed Rasante. These were heavily used, flying in tight formations and using co-ordinated defensive fire to defend against fighter attack, while returning individually at low levels. Although many R-Zs were damaged by ground fire, complete losses were relatively low with 36 surviving to be captured by the Nationalists at the end of the war in April 1939.