In 1936 Grigorii (according to Shavrov, Georgii) Ivanovich Bakshayev, aged 18, joined the UK GVF, the instructional combine of the civil air fleet. He was eager to test his belief that a superior aeroplane could be created by arranging for it to have a large wing for take-off and landing and a smaller wing for cruise. As the UK GVF was in Leningrad the NIAI adopted the idea. Called RK (Razdvizhnoye Krylo, extending wing), and also LIG-7 because it was the seventh project of the Leningrad Institute GVF, the aircraft was built quickly and was first flown in August 1937. Remarkably, the RK, LIG-7 aircraft can be hyper-efficient is doubtful, though the LK-1 did have useful STOL (short take-off and landing) qualities. system worked smoothly and reliably (better in the air than on the ground), and it led to the even more unconventional RK-I fighter (already posted in this forum) (Soviet X-Planes Yefim Gordon and Bill Gunston)