LIFT: This is the force “lifting” the aircraft up in the air. In most cases, the majority of an airplane’s lift comes from its wings.

The Four Forces of Flight

There are always four basic forces acting on an airplane in flight. These laws of physics are the same for something as heavy as a 747 weighing 250,000 pounds or an airplane as little as a Piper Cub weighing less than 1,000 pounds.

The four forces that make an airplane fly are:

WEIGHT (or gravity): This is the force drawing the airplane back toward the earth. The heavier the aircraft, the greater this force is.

THRUST: This is the force propelling the airplane forward. In most cases, an airplane’s thrust is created by its engine.

DRAG: This force works against the forward movement of the airplane. Drag can be caused by the shape of the airplane itself, or by disturbed airflow.

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