The Borovkov-Florov I-207 (''Istrebitel'' – fighter) was a fighter aircraft designed and built in the
USSR
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet ...
from 1936.
Development
In 1935, two designers from
GAZ-21 (''Gosoodarstvenny Aviatsiya Zavod'' – state aviation plant/factory), at Gor'ky began work on a new high-speed biplane fighter design. Borovkov and Florov drew heavily on their experience working in the
Polikarpov I-16 program, producing 'Prototype No.7211' (''Izdeliye 7, Zavod 21, Samolyet 1'' – article 7, factory 21, aircraft 1). The goal was the smallest possible aircraft with the most powerful engine then available in the Soviet Union, the
Mikulin M-85 14-cylinder radial, a licensed-built
Gnome-Rhône K14 Mistral Major. The No.7211 was a sleek biplane with fully cantilever outer wings, the upper centre-section being supported by four well-streamlined cabane struts. The No.7211 performed its maiden flight on 1 June 1937, but crashed on take-off due to engine failure.
The first production prototype was powered by the
Shvetsov M-62 radial, (license-built
Wright Cyclone
Wright Cyclone was the name given to a family of air-cooled radial piston engines designed by the Wright Aeronautical Corporation and used in numerous American aircraft in the 1930s, 1940s and 1950s.
Background
The Wright Aeronautical Corporatio ...
). Retaining the open cockpit, it featured a smooth close fitting cowl, fixed landing gear, and was fully armed with four
ShKAS 7.62-mm machine guns in the forward fuselage. It was first flown in April 1939 and led to improvements on the second production prototype. The second aircraft still featured the fixed gear, but had the improved
Shvetsov M-63 radial of and the lower wings were strengthened to accept either two
FAB-250
The FAB-250 is a Soviet-designed general purpose air-dropped bomb with a high-explosive warhead, primarily used by the Russian Air Force, former Soviet republics and customer countries. It is very widespread throughout the Third World and use ...
bombs or
Merkulov DM-4 ramjets for a rapid climb on takeoff, with a first flight in late April or early May 1939 proving its high performance - maximum airspeed 416 km/h (258.5 mph) at 5000 m (16,404 ft) and 18 m/s (3,543 ft/min) rate of climb after take-off.
One aircraft featured a retractable landing gear that rotated to lie flat in a small landing gear bay under the fuselage. This improved the top speed over the fixed gear version by 20 mph (32.5 km/h). Two aircraft reputedly saw combat in
Finland
Finland, officially the Republic of Finland, is a Nordic country in Northern Europe. It borders Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of Bothnia to the west and the Gulf of Finland to the south, ...
during the
Winter War
The Winter War was a war between the Soviet Union and Finland. It began with a Soviet invasion of Finland on 30 November 1939, three months after the outbreak of World War II, and ended three and a half months later with the Moscow Peac ...
, but there is little evidence for this.
The fourth production prototype featured a fully enclosed cockpit, a geared M-63 engine and a large smooth spinner that gave the little airplane a dart-like look. Though performance was quite impressive for a biplane fighter, the type was not accepted for manufacture, and all testing came to a halt with the German invasion of 1941.
Variants
* 7211 – The initial prototype aircraft, with an M-85 engine assembled from parts imported from France, crashed on first take-off due to engine failure.
* I-207 – Four prototype and pre-production aircraft with M-62 engines.
* I-207/M-63 – Three aircraft with M-63 engines plus provision for two FAB-250 bombs or two Merkulin DM-4 ramjet boosters under the lower wings. One aircraft later fitted with retractable main undercarriage retracting rearwards and rotating 90° to lie flat in the lower wings.
Specifications (I-207)
See also
References
* Gunston, Bill. ''The Osprey Encyclopaedia of Russian Aircraft 1875 – 1995''. London, Osprey. 1995.
* Taylor, Michael J.H. '' Jane's Encyclopedia of Aviation''. Studio Editions. London. 1989.
External links
* http://www.ctrl-c.liu.se/misc/ram/x-florov.html
* http://www.pavlamodels.cz/katalogy/detail.php?k=akk&c=72024
* http://www.internetmodeler.com/2000/december/first-looks/pavla_i207.htm {{Webarchive, url=https://web.archive.org/web/20150924035548/http://www.internetmodeler.com/2000/december/first-looks/pavla_i207.htm , date=2015-09-24
Polikarpov aircraft
1930s Soviet fighter aircraft