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How does a helicopter create lift without moving forward at a fast pace?


Helicopters actually don’t create lift. They create vertical thrust using rotors. As their rotors spin, they create a difference in air pressure on top of and below the blades as they move. Slow moving high pressure air under the blades pushes the helicopter up into the faster moving, low pressure air on top of them.

Planes need a running start, because they need air actively moving over their static wings. The difference in air pressure on top and on the bottom of an airplanes wing is caused by the air moving around its shape – so to start flying, you need to already have air flowing over your plane. Helicopters can just move their rotors at a fast pace instead of the whole vehicle.

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