In January 1923, Spanish engineer Juan de la Cierva successfully flew his C.4 gyrocopter for the first time.
In 1925 he began demonstrating it in France, England, and the United States. Later that same year he started the Cierva Autogiro Company, and in 1926 he demonstrated the latest developments successfully in France and Germany. In 1928 he managed to fly across the English Channel from Croydon to Paris in 18 minutes. He then took a 5 000 km trip across Europe showing off his creation.
A crash in 1927 led to incorporation of a “drag hinge” at the hub to allow each blade to drag back a little or pivot forward slightly as it rotated, to relieve stresses. He also developed a mechanical starter to spin the rotor before takeoff.
In the next ten years more than five hundred gyros were built around the world: in Britain, , Germany, France and in Russia. In 1928 a Cierva model C-8 gyrocopter flew for the first time in the United States. In 1929, two companies manufactured gyros in the United States, and in August that year the first public demonstration of a Cierva machine took place the Cleveland Air Races. A two seater with a top speed of 145 kilometres per hour cruised at 120 kilometres per hour.
In 1932 the development of the “direct control” rotor led to the elimination of ailerons and stub wings. The rotor was mounted so that it could be tilted, giving a force that would pull the gyro in the desired direction. This was a great improvement to earlier Gyrocopters, that had had rudders and controls like an airplane.
The next major improvement occurred in 1934. A gyrocopter was developed could perform a vertical “jump” takeoff. It was highly successful, and for the first time there was a rotating-wing flying machine that could lift itself vertically into the air.
In the 1930s, gyros serviced in the armies in the US, France, the Soviet Union, Britain and Japan, and it was used for airmail in the US.
Ironically, since his life goal was to invent an aircraft much safer than an airplane, Cierva died in an airplane crash in late 1936.