Grušin BB-MAI

Grušin BB-MAI
Грушин ББ-МАИ
In the MAI (Moscow aviation institute - МАИ, Московвский авиационный институт) was created and the next the plane P. D. Grušina - attack aircraft and bomber for the přifrontovou the activity of the BB-MAI. Machine somewhat smaller dimensions, the classical scheme, but with the engine M-105 on the higher performance (1050 to. s). The engine was mounted filling dmýchadlo CIAM, powered by the exhaust gases.
The aircraft was designed in the years 1938-1939. as a ground attack aircraft and as a přifrontový bomber. Wing BB-MAI - double-girder, composed of the three sections of the shape, sculpted from bakelizované plywood. When were the individual sections inserted one into the other, their front edge, forming a wall of the beam, and reinforcement to create the cover of the wing. Section and the wing were attached with glue VIAM B-3, in their assembly created a monolithic box girder. The thickness of the coating on the leading edge of the wing was 5 mm in the tail parts to 3 mm, and between the walls of the beams - to 25 mm. The fuselage was monocoque construction of the bakelizované plywood and associated with the same glue. The surface of the BB-MAI, as well as with the previous aircraft, it was polished to a high gloss.
Production technology structure made of bakelite plywood helped in the race to introduce specialists VIAMu. The machine was equipped with shooting tower, confluent with the canopy pilot.
On the BB-MAI was for the first time in the USSR used three-wheeled chassis with nose wheel. For the nose wheel was placed radiator. The wheels would drag in the wings in the direction of the aircraft fuselage with the rotation of the wheels due to the feet. The wing was relatively small: surface area of 15.2 m2, tapering to 3.5. During the take-off weight of around 3500 kg and the low surface of the wing was the specific load on the wing around 210 kg/m2. (Such large loads was adopted in order to increase the maximum flight speed.) On the wing were installed automatic slots.

The construction of the aircraft began in 1939, at the end of 1940 was completed. Chief engineer of the construction of the machine was And. And. Lebedinskij( А. А. Лебединский), lead engineer testing And. And. Manučarov (А. А. Манучаров ). A test pilot became a graduate of the MAI AND. N. Grinčik (А. Н. Гринчик). Stretchy construction led to the fact that the first flight of the airplane took place only in December of 1940, when in the VVS interested in this machine has already waned. In addition, the USSR was attacked by hitler's Germany, which the development work also helped. Alone Grušina at the time appointed the main designer of KB Charkovského aviation factory no. 135, and KB, MAI, acting in the course of a few years, the role of the "kindergarten" of future engineers and designers, was repealed..