Have you ever wondered who was the first person to make a flying machine? It was not the Wright brother. If you want to know just keep reading more about the history of the planes and how it evolved.
             Whenever I see a plane the first question that comes to mind is "What is causing that thing to stay off of the ground?"
             Well I finally discovered the answer. When a plane flies there are four forces at work that keep the plane flying. These forces are lift, thrust, gravity, and drag.
             Airplane wings are created with a special design called an airfoil. The airfoil design bulges out more on the top than on the bottom. This causes the air that hits the wing to go off into two different streams, one that goes over the top and one that goes under, and they both meet up in the back.
             The air moving over the top of the wing is caused to go faster than the slower moving air on the bottom. Faster moving air has less pressure, so this causes the pressure on the bottom of the wing to be greater and the plane is lifted. This effect is known as the Bernoulli Principle. This principle was developed by Daniel Bernoulli who was a Swiss mathematician and physician. He developed the principle in the 18th century. When a plane creates lift it overcomes the force of gravity that is pulling the plane down.
             Air pressure plays a big part in flight also. When you think about flight you have to realize that air pressure is a force pushing on every square inch of an airplane. When a plane is parked the air pressure is distributed evenly around the plane's surface. When a plane is in flight the pressure on top of the wings pushes down less and the pressure on the bottom of the wings pushes more. This is what causes the plane to feel a lift.
             Another force that has a great part in flight is drag. Drag is the force pulling the plane backwards. Drag is created when the air collides with the airplanes wings and creates fricti...