Three years later Berliner used the fuselage of a Nieuport biplane with a 4.5m rotor mounted on an outrigger on either side of and slightly forward of the cockpit. Control vanes, similar to those used on their 1919 coaxial machine, were used in the slipstream.
Longitudinal control was by a small variable pitch lifting propeller near the tail. Hovering up to 3.3m was accomplished in June 1922, and flew about 90m.
Despite the fact that overall performance was unsatisfactory, the Smithsonian Institute considers the Berliner machine as the first helicopter to make a controlled flight on the basis of these tests. Berliner continued his efforts and built two additional machines, but they were short take-off convertaplanes incapable of vertical flight.