By the early 1930s,. KB, headed by KA. Kalinin, It constitutes a collective, able to solve completely new and complex tasks. So, in terms of the CB to 1929-1930,. bore the task to build a three-engine passenger aircraft K-7 22 seats. However, from the production of the machine refused to continue to index the K-7 was given transcontinental aircraft, who began designing in 1928 g. later, KA. Kalinin wrote: "The idea to construct the plane K-7, I was born in another 1925 g. AT 1929 g. I formed the project, which after two years of refinement was launched…
When you create a new large machines lead the way towards new schemes of aircraft, towards the use of the wing to accommodate cargo… To make the transition to flying wing, it became necessary to build a machine on the principle of "all in the wing". Initially wing K-7 was designed wooden, but due to lack of safety margin moved to all-metal. The plane is a gigantic elliptical wing thick airfoil span 53 m, from which came two triangular-section tail booms, bearing tail. The wing had a width center section 6 m, length 10,6 m and height 2,33 m, where the premises were placed for people and goods. For the center-console docked, that was taken 14 fuel tanks. In front of the aircraft cabin positioned axis, where two pilots placed, navigator, radio operator and mechanic. The remaining seven crew members were in the other compartments of the aircraft. Initially, the aircraft was calculated at six engine BMW, but then installed domestic AM-34. Due to lack of gears on engines and their low thrust had to install seventh pusher motor at the trailing edge of the wing between the tail boom. The original design of the chassis allows the aircraft to have a horizontal parking position.
The plane K-7 was designed in two embodiments,: civilian and military. The first option involves carriage 128 passengers at a distance 5000 km. In the embodiment of "luxury" involves the installation of bunk cabins 8 people each - all 64 berths. The design allows engineers to approach flight to the engine running. The military version of the aircraft was a real "flying fortress". It was supposed to set up 12 gun emplacements (eight 20-mm guns and eight 7.62-mm machine guns). special trolley has been designed to deliver even shooters to two tail machine guns, moves within tailboom. In terms of defense aircraft had virtually no "dead zones", wherein any point of view both at least three arrow. The stock of bombs fluctuated depending on the flight distance from 9,9 tons to 16,6 t.
Technical aircraft K-7 project was completed in early 1932 g. In the central part of the wooden model was built by the yard of the factory. In November 1932 g. construction giant started, and in August 1933 g. the aircraft was ready for test. After taxiing and the approach identified a large vibration tail rudders. We had to make tail biplane. The first flight of the aircraft makes a K-7 21 August 1933 g. with a crew led by a test pilot MA. Snegirev. At the site of the second pilot sat himself KA. Kalinin. Tests have shown good performance of the aircraft. Vibration of the vertical stabilizer stopped, horizontal but still remained. To determine the maximum flight speed of the volumetric base plane 21 November has made repeated flights (in the first flight, due to an error on the ground experimental measurements have not turned). Plane when flying at maximum speed crashed, killing 15 crew, five remained alive. K-7 plane went down in history of world aviation as a bold step, because such aircraft at the time did not exist in any country of the world.
The performance characteristics of the aircraft K-7
– chief designer: TO. A. Kalinin
– First flight: 21 August 1933 of the year
– End of operation: 21 November 1933 of the year (crashed)
– units produced: 1
Aircraft K-7 crew
– 12 people
The dimensions of the plane K-7
– Length: 28 m
– Wingspan: 53 m
– wing area: 452 m²
Weight of the aircraft K-7
– empty weight: 21 000 kg
– Maximum takeoff weight: 40 000 kg
K-7 aircraft engine
– 7 34 × AM
– engine power: 7 × 750 l. from.
Aircraft K-7 Speed
– full speed: 234 kmh
Range aircraft K-7 flight
– 1000 km
K-7 aircraft service ceiling
– 5500 m
Armament K-7
– Small-pushechnoe: 8 caliber guns 20 mm, 8 caliber machine guns 7,62 mm
– combat load: to 16 600 kg
K-7 photo Aircraft
