Gyrocopters were invented and first flown in the U.S by Dr. Igor Bensen in 1955. Before the Gyrocopter, there was the Gyroglider of the 1940’s. The original “autogiro” was invented by Sr. Juan de la Cierva, a Spanish aeronautical engineer around 1923. He had been injured while testing an airplane design, and vowed to build a safe aircraft that would not stall or spin, and descend safely in case of engine failure. Cierva came to the U.S to form his own company. About 200 autogyros were manufactured and sold during the 1930’s, where they saw action for agricultural work and by the US Army.
The name “Gyrocopter” combines the descriptions of the flying features of the autogyro and the helicopter. The name Gyrocopter is owned by the Bensen Aircraft Corporation and is actually a brand name like Kleenex. The FAA refers to these flying machines as gyroplanes, but whether they are referred to as gyrocopters, gyroplanes or autogyros, they are all talking about the same thing.
The first autogyros used short wings, but later the function of lift and flight controls were transferred to the rotor.
The rotor of the autogyro is not powered in flight. The airflow goes through the rotor from the bottom up. It is exactly the opposite of the helicopter, where the airflow comes from the top of the rotor. Because there is no power on the rotor, there is no torque against the airframe.
The helicopter came about much earlier than the autogyro. The first successes came in France as early as 1907, but the helicopter really didn’t blossom until 1940 when inventor Igor Sikorsky developed the tail-rotor type of helicopter design we are familiar with even to this day. The helicopter’s main advantages include its abilities to take off and land vertically, hover, and fly sideways and backwards, but the cost of this advanced flying machine puts it out of the reach of most average people.
The helicopter has a nose-down attitude during flight. That’s because it must tilt its rotor forward and pull itself forward by the rotor. This is just the opposite of the autogyro, which has the rotor tilted backward, with an almost level attitude during forward flight. Its forward motion comes from a pushing propeller.
Returning to the term “gyrocopter”… It is really derived from the similarities between helicopters and autogyros, for there are certain circumstances where the helicopter flies like autogyros and vice versa. The helicopter flies like an autogyro when its engine quits or power drops to zero. Almost all helicopters have the ability to fly in auto-rotation, where their rotors are turned by the force of wind alone, just as in autogyros. In a helicopter, this is a safety feature for descent under control in case of an engine failure.