A helicopter is a type of rotorcraft in which lift and thrust are supplied by horizontally spinning rotors. This allows the helicopter to take off and land vertically, to hover, and to fly forward, backward and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft and many forms of short take-off and landing (STOL) or short take-off and vertical landing (STOVL) aircraft cannot perform without a runway.
A Bell 206 helicopter operated by the Los Angeles Police Department Air Support Division
Cabin view looking out from a helicopter in flight
Bell 412CF looking forward from the tail, showing its twin turbine endinge exhausts
1956 Hiller YROE-1 one-man "Rotorcycle" being tested at NASA Ames Research Center
A rotorcraft or rotary-wing aircraft is a heavier-than-air aircraft with rotary wings or rotor blades, which generate lift by rotating around a vertical mast. Several rotor blades mounted on a single mast are referred to as a rotor. The International Civil Aviation Organization (ICAO) defines a rotorcraft as "supported in flight by the reactions of the air on one or more rotors".
A Bell 47 helicopter, an early example of a powered rotorcraft
A Bell UH-1 Iroquois helicopter
A Magni M-16 Tandem Trainer autogyro
A Fairey Rotodyne prototype gyrodyne