K-12 (ВС-2) - experimental, tailless military aircraft - close-range bomber, reconnaissance and artillery spotter. Approaching the "flying wing" according to the scheme, the aircraft was of interest for creating a high-speed high-altitude rocket aircraft in the future.
The aircraft was designed in 1934, the first flight in the fall of 1936, flew P.M. Stefanovsky. Tests have shown low efficiency of vertical tail at low speeds, insufficient stability and controllability.
The plane on Aviation Day, August 18, 1937, decorated in a bright red fairytale image of the "Firebird", was shown at the Tushino parade.
The impression of the car from the test specialists was as follows: "When creating this "tailless" aircraft, a number of problems were successfully resolved. ВС-12К in an incomplete form is dangerous.
With the synchronous operation of the motors, the machine stably and reliably maintains all modes and is easily controlled in flight.
The dimensions of the entire aircraft are too high. The fuselage is especially large, which also has poor aerodynamics. This negates all the advantages of the tailless scheme in obtaining high speeds.
Production design is satisfactory. "
General conclusion: the VS-2 aircraft, even with the installation of modern engines and retractable landing gear, will not be better than the serial SB aircraft.
Decision: all work on the BC-2 aircraft should be immediately stopped as unpromising, and the released resources should be directed to the production of aircraft necessary for the Red Army Air Force and having a future.