Single-seat close-cockpit helicopter with 85hp radial engine and two coaxial rotors. Completed by De Bothezat's colleagues after he passed away in 1939.

De Bothezat who, after abandoning his first helicopter in 1923, had created a firm for the design and manufacturing of industrial fans, returned in 1937 to the helicopter: he created then the Helicopter Corporation of America and built a coaxial helicopter whose testing was entrusted to a Russian ace of World War I Captain Sergievsky.

http://www.helicopteros.com.br/auhisi7.htm