"In early 1936, the AIR FORCE offered a number of Management. Design bureaus to begin designing combat high-speed monoplane, defined as ground attack aircraft or military reconnaissance aircraft (XB). Actually sought to create a multipurpose aircraft capable of a Stormtrooper following technical requirements:
1. speed of 450-470 km/h.combine functions, far Scout and light bomber. As the powerplant used engine am-34frn, takeoff power rating 1200 HP-it seemed the most appropriate at the time for the implementation of this task, as was the real product of the domestic aircraft industry. For project preparation the
2. normal Range 2000 km, with overload-4000 km.
3. Crew-2 person.
4. For bomber bomb load was to be 400-500 kg, maximum, when overloading is 1000 kg.
During the year, design collectives Grigorovich, Polikarpova, Neman, Kocherigina, dry and Ilyushin made their proposals at the level of preliminary designs.
December 20, 1936 head of ICPC M.m. Kaganovich in its report note in the Government "of resources-Scouts along with great range and speed," confirmed the fact of most of these projects are multi-purpose aircraft. Grigorovich on projects indicated that it developed two variants: KB nizkoplana and vysokoplana.
Vysokoplana Grigorovich project with the installation of the engine high above the wing was originally designed with the subsequent processing of the seaplane. Against him stated that this option gives a good overview and shelling in the forward hemisphere for the observer. The negative side was called the complexity of installation and operation of the engine, reducing the maximum speed and unusual for land vehicles equipment piloting.
However, prior to detailed development of both projects is vysokoplana and nizkoplana is not reached. In early 1937, the idea of establishing itself a multipurpose plane visibly transformed and received a sequel in the form of a draft-Smith ", now engine-oriented m-62. Grigorovich constructor in this program is no longer involved.The main settlement characteristics of LC-3 (DG-56)
Wingspan, m 20.0, The length of the flight line, m 13.0, Height, parked, 4.9 m, Wing area: 53.0 m², Design weight (kg) 1940 Full load, kg 2220
Gross weight, kg 5675
Wing loading, 111.0 kg/m2
Bombs, kg. 200 (overload)
Maximum speed, in the 5000 m, km/h. 428, Flight range (km) 1900
Light cruiser LC-3 (DG-56)
The exact date of the project or abandoning its continued development. Probably, the aircraft design was carried out throughout the d. 1935 it was at this time in the leadership of the Red Army AIR FORCE celebrated interest in high-speed flexible aircraft for which used the definition "light cruiser" (LC). Tasks for such aircraft were called protection of its bombers and destroying enemy aircraft, flying in large units. The project "light cruiser" Grigorovich was designated BM-3 (DG-56). Aircraft intended under two engines "Hispano Suiza" 12Ybrs declared maximum power for 860 HP DG-56 stood out graceful outline, the plane had landing gear, smooth lining. The crew consisted of two or three people. Armament was expected from two dinamoreaktivnyh guns APK-4 calibre 76 mm or 2 x SHVAK Cannon-calibre 20 mm."