Grigorovich I-2

Grigorovich I-2 oli Neuvostoliitossa valmistettu ensimmäinen kaksitasoinen hävittäjä jonka tarkoitus oli muodostaa huomattava osa Neuvostoliiton ilmavoimille. 

Kone oli kehitetty versio Grigorovich IP-1 lentokoneesta. Ensilento oli 4. marraskuu 1924, ja ohjaaja oli AI Zhukov.

M-5 moottori oli Neuvostoliitossa lisenssillä valmistettu Liberty L-12 moottorin kopio.
Uudistettu I-2 A sarjan koneiden tuotanto oli yhteensä 211 lentokonetta.
Konetta valmisti Smolenskin Lentokone liikenteen tehdas No.3.
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Operators: Soviet Air Forces
Specifications: I-2bis
Crew: One, pilot
Length: 7.32 m (24 ft 0 in)
Wingspan: 10.80 m (35 ft 5 in)
Height: 3.00 m (9 ft 10 in)
Wing area: 23.4 m² (252 ft²)
Empty weight: 1,152 kg (2,540 lb)
Loaded weight: 1,575 kg (3,472 lb)
Powerplant: 1 × M-5 water-cooled 45-degree V12 engine, 298 kW (400 hp)
Maximum speed: 235 km/h (147 mph)
Range: 600 km (374 miles)
Service ceiling: 5,340 m (17,515 ft)
Rate of climb: 420 m/min (1,377 ft/min)
Wing loading: 67 kg/m² (14 lb/ft²)
Power/mass: 0.19 kW/kg (0.12 hp/lb)
Armament: 2 × 7.62 mm PV-1 machine guns

The Grigorovich I-2 was a biplane fighter aircraft of the Soviet Union, the first indigenous fighter to enter service in substantial numbers. Developed from the Grigorovich I-1, it first flew on 4 November 1924, piloted by A.I. Zhukov. 
The M-5 engine was a Soviet copy of the Liberty L-12.

Production of the redesigned I-2bis was 211 aircraft. Production was performed by Aviation Repair Plant No.3 in Smolensk.
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The Grigorovich I-1 was a Soviet fighter prototype of the 1920s. It was the first land-based fighter developed by the Grigorovich Design Bureau, who had previously concentrated on water-borne aircraft such as the Grigorovich M-5 of 1914.

Initially, design was started on a single-seat fighter by Dmitry Pavlovich Grigorovich, to compete with the Polikarpov I-1 biplane. The finished aircraft, finalised in 1924 and produced at Factory No. 1, at Khodinka, near Moscow, was a single-seat, single-bay biplane of wooden construction, with the forward portion of the fuselage being covered in plywood and the rear having fabric skinning. In development, a major problem was that of engine cooling - various methods were tested including radiators attached to the undercarriage legs, but in the end a radiator suspended beneath the engine was used.


After an initial flight in January 1924, testing took place in the spring of that year. The I-1 was found to have adequate speed for its purpose but its construction and therefore its flight were unstable, and its climb rate was found to be insufficient with repeated stalls. Therefore the prototype was abandoned, and Grigorovich refined the design into the Grigorovich I-2 which later entered service in the Soviet Air Force