Helicopter is flying object which is gift of science.A helicopter is an aircraft that is lifted and propelled by one or more horizontal rotors, each rotor consisting of two or more rotor blades. Helicopters are classified as rotorcraft or rotary-wing aircraft to distinguish them from fixed-wing aircraft because the helicopter achieves lift with the rotor blades which rotate around a mast. The word 'helicopter' is adapted from the French hélicoptère, coined by Gustave de Ponton d'Amecourt in 1861, which originates from the Greek helix/helik- (ἕλικ-) = "spiral" or "turning" and pteron (πτερόν) = "wing".[1][2]
The primary advantage of a helicopter is from the rotor which provides lift without the aircraft needing to move forward, allowing the helicopter take off and land vertically without a runway. For this reason, helicopters are often used in congested or isolated areas where fixed-wing aircraft cannot take off or land. The lift from the rotor also allows the helicopter to hover in one area and more efficiently than other forms of vertical takeoff and landing aircraft, allowing it to accomplish tasks that fixed-wing aircraft cannot perform.
Although helicopters were developed and built during the first half-century of flight, some even reaching limited production, it was not until 1942 that a helicopter designed by Igor Sikorsky reached full-scale production,[3] with 131 aircraft built.[4] Even though most previous designs used more than one main rotor, it was the single main rotor with antitorque tail rotor configuration of this design that would come to be recognized worldwide as the helicopter.
The primary advantage of a helicopter is from the rotor which provides lift without the aircraft needing to move forward, allowing the helicopter take off and land vertically without a runway. For this reason, helicopters are often used in congested or isolated areas where fixed-wing aircraft cannot take off or land. The lift from the rotor also allows the helicopter to hover in one area and more efficiently than other forms of vertical takeoff and landing aircraft, allowing it to accomplish tasks that fixed-wing aircraft cannot perform.
Although helicopters were developed and built during the first half-century of flight, some even reaching limited production, it was not until 1942 that a helicopter designed by Igor Sikorsky reached full-scale production,[3] with 131 aircraft built.[4] Even though most previous designs used more than one main rotor, it was the single main rotor with antitorque tail rotor configuration of this design that would come to be recognized worldwide as the helicopter.
