During the late 1950's and early 1960's three commercial gyroplanes were developed and manufactured by private companies. The Umbaugh (later the Air and Space 18A), the Avian, pictured below, (a Canadian design of that same period that reached FAA certification, but was never produced) and the McCulloch J-2, each having two seats, were FAA type certified. The designers of these three aircraft, however, did not fully use the gyroplane technology created by their 1930's predecessors. In fact, to make certification easier, they used rotor head and blade technology from the helicopter industry (omitting the most valued component of that technology, the collective pitch control).

Pitcairn and Kellett (and others such as Goodyear Rubber, Autogyro Company of America, Buhl, Alfaro, etc.) had learned things about gyroplane aerodynamics, disk loading, power loading, etc., that were overlooked in these three designs. The twist in the rotor blades of a helicopter, for instance, is backward from what would be useful in a gyroplane. Disk loadings were too high and power loadings were too low. As a result, they did not perform well and the companies failed. The Umbaugh and the McCulloch each delivered about 100 units.

Also during the 1950's, Igor Bensen, a colleague of Igor Sikorsky, developed a homebuilt kit gyroplane for amateurs. He called it the "gyrocopter". His idea for this open-frame model came from a German observation gyroplane (above) towed behind U-boats during the war. Homebuilt kits, most of which seat one person, are popular today, with more than a dozen manufacturers in the market.