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Helicopters

Helicopter is a kind of rotorcraft, in which the lift and thrust are provided by the rotor. This allows the helicopter to take off and land vertically, hover and fly forward, backward and laterally. These attributes enable helicopters to be used in congested or remote areas where fixed wing aircraft and many forms of VTOL aircraft cannot be performed.

The helicopter was developed and manufactured in the first half century of flight, of which focke Wulf fw61 was the first helicopter produced in 1936. Some of the helicopters were limited in production, but it was not until 1942 that Igor Sikorsky's helicopter was fully put into mass production and 131 aircraft had been built. Although more than one main rotor was used in the early design, the single main rotor with anti torque tail rotor configuration has become the most common helicopter configuration. Tandem rotor helicopters are also widely used because of their greater payload capacity. Coaxial, tilt rotor and composite helicopters are flying today. Quadcopter helicopter was first invented in France in 1907, and other types of multi axis helicopters have been developed for special applications, such as drones.