Pavel Ivanovich Ekonomov, profesional aviation carpenter and joiner, was a prolific inventor and made various propositions while he was working at MAI in 1930s. In 1936 he constructed primitive but large rotary-wing craft with two contra-rotating sets of two-blade rotors (virtually large wings) of 22m diameter. Thick wing profile, each with aileron. Called Zhiroplan; never completed.

Bill Gunston "The Osprey's Encyclopedia of Russian Aircraft", 2000