How do Helicopters Fly?

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The helicopter is a very useful and an unusual aircraft, unusual in the sense that it can fly in any direction and hover in mid-air. Invented in 1930s, it is used for all kinds of jobs especially sea and mountain rescue. It can take off and land vertically and can in areas too small for ordinary aircraft. The engine drives the rotor of the helicopter. The blades of the rotor on rotating generate the lift. When a helicopter hovers, the blades rotate at the same pitch. The weight of the craft balances the upward pull of the rotor. To ascend, the angle of attack of the blades is increased. To move forward, the blades are tilted forward. By adjusting the blades, the helicopter can fly in any direction.

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