Autogyro: The photographic story of early plane-helicopter hybrids, 1925-1940

A Spanish engineer and aeronautical pioneer, Juan de la Cerva, developed the original "Autogiro". Its name was derived from the self-stabilization accomplished by a four-bladed horizontal screw rotated by the wind generated in the sky.

In addition to the name autogyro, they are known as gyrocopters, gyroplanes, and autogyros. They were the first rotary wing aircraft to fly successfully with adequate control.

The autogyro was invented to solve the main issue: how to design an aircraft that will not crash when the engine stops? This question was inspired by the failure of Cierva's previous projects. In 1919, Cerva entered an aircraft design competition in which a large three-engined bomber piloted by Captain Julio Ríos Argueso, crashed in its initial flight due to engine stalling.

However, Cierva was fully committed to developing a safe means of air travel which he did not give up. Between 1920 and 1923 they progressively developed autorotation in a series of C.1, C.2 and C.3 models, but this would be their fourth model to conquer the air. His designs served as the basis for all future rotary wing aircraft and were later licensed to companies in the UK, US and elsewhere.

In later years, Sirva-licensed Harold F. Amazing planes were produced by Pitcairn. In February 1929, Pitcairn won the U.S. license for Cerva's inventions and autogyro patents.

Autogyros were used for roof-to-roof urban mail delivery, and some were even put to military use during World War II. The autogyro fell out of favor in the late 1930s with the rise of helicopters that could not only take off and land with precision, but could also hover for extended periods of time.

Another factor that prevented the autogyro from being accepted was purely psychological. Even though helicopters were not successful until 1935, they were developed into airplanes for a long time. The general public knew about helicopters, and understood the principle of a powered rotor.

Autogyros had an unpowered rotor that rotated due to aerodynamic forces. Most people didn't understand how it worked and therefore didn't trust it. Although it is actually safer than a helicopter or airplane, people did not realize this. They wanted something driven.

After the helicopters were successfully flown and the companies that designed them received military grants for further research, Autogyro was pretty much abandoned.

Except for a handful of concepts and only a handful of attempts at civilian design, the Autogyre survived only as a home-built aircraft, and that mostly as an ultralight.