The I-207 (official designation: Borovkov-Florov I-207) was a Soviet biplane fighter designed by A. A. Borovkov and I. F. Florov in the late 1930s. The prototypes were built at the Gorky Aircraft Plant No. 21 named after Ordzhonikidze in 1938–1939, and the first flight took place on June 29, 1939.[1]
Design and specifications
The aircraft was built to the classic biplane layout, with fixed landing gear and an open cockpit. The powerplant was the Shvetsov M-62 engine (a licensed copy of the American Wright R-1820 Cyclone), a nine-cylinder single-row air-cooled radial with a supercharger, rated at 1,000 hp for takeoff at 2,200 rpm; it drove a two-blade VISh-26 propeller 2,800 mm in diameter. Empty weight was 1,598 kg and takeoff weight 1,950 kg. Armament consisted of four fixed 7.62 mm ShKAS machine guns in the nose of the fuselage, with 550 rounds per barrel.[1]
Performance: maximum speed 436 km/h at an altitude of 4,750 m, rate of climb 13.44 m/s, time to climb to 5,000 m 6.2 minutes, service ceiling 9,150 m, range 700 km. Wingspan was 7.0 m, length 6.35 m, height 2.85 m, and wing area 18 m².[1]
Development and testing
The reason for building new prototypes was the crash of the original airframe, No. 7211, in May 1938: afterward the designers were tasked with preparing the aircraft for series production. Both reworked prototypes retained the fixed landing gear of the earlier design, but differed in the modified cowling of the M-62 engine — the air intake was moved to the upper part of the cowling — and in the installed ShKAS machine guns. The prototypes were ready in spring 1939; testing was carried out by test pilots P. M. Stefanovsky, L. M. Maksimov, and N. I. Nikolaev.[1]
Testing showed that an aircraft with fixed landing gear was conceptually obsolete: its performance fell between that of the I-153 and the I-16. The aircraft's small dimensions further limited the diameter of the propeller that could be used. Further work under the program was shifted to prototypes with the M-63 engine.[1]
The Nizhny Novgorod connection
The sole prototype (or both, if the two airframes are counted) of the I-207 was manufactured at Aircraft Plant No. 21 named after Ordzhonikidze in the city of Gorky (now Nizhny Novgorod) between 1938 and June 1939.[1] Plant No. 21 was one of the main producers of Soviet fighters of the period and was associated with a whole series of experimental designs by Borovkov and Florov.
Sources
- valka.cz — Borovkov-Florov I-207 : Ostatní