Technical data
Year	1911
Crew	1
Engines	1*25hp Anzani
Wingspan	8m/4.6m
Wing area	17m²
Power load (kg/hp)	13

Biplane by G.K.Demkin

Picture (24k) from "History of aircraft construction in the USSR", Vol.1 p.86

Tractor biplane, resembling BIS-2 and S-3, but lower wing was substantially smaller than the upper one. Struts had oval cross-section, whole design was more clean. Despite low engine power, short straight flights were performed during 1911.

References:

"History of aircraft construction in the USSR", Vol.1 p.85;