Lift is the force which causes the airplane to fly. Without lift the airplane would never get into the sky. Lift is created in two ways: dynamic lift (also known as Newtonian lift) and induced lift (or Bernoullis lift).
Dynamic lift is the force seen when placing a hand out of a car window. When the hand is tilted upward, the force of the wind reflecting downward causes the hand to move upward. This is an effect of Isaac Newtons third law: for every action there is an equal and opposite reaction. This means that whenever something moves in one direction, it causes something else to move in the opposite direction. In dynamic lift, the air moving downward causes the wing to go upward.
In the eighteenth century a Swiss scientist named Daniel Bernoulli came up with a theory: "As the velocity of a fluid increases, the pressure decreases." In science air is considered to be a fluid like water, so this theory applies to airplanes. The shape of the airfoil takes advantage of Bernoullis principal to create lift. The curve of the top of the wing is much larger than the curve on the relatively flat surface of the bottom of the wing. This means that the air needs to move faster when going over the top than when it goes underneath the wing. This creates a low pressure on the top part of the wing which acts like a vacuum and sucks the wing upward, thus creating lift.
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