How does an aircraft fly?

Air, just like water, has supporting power, or lift. Think about what happens during a storm. Objects of all kinds are lifted by the wind and blown away. The harder it blows, the larger the objects the wind can carry. An aircraft simply creates its own storm. The engines push the aircraft forward on the ground, and the faster it moves, the faster the air “storms” over the wings. The wings have a specific shape, where the upper surface is curved slightly upward. This forces the air passing over the wing to travel further than the air passing under the wing. Behind the wing, the two air currents rejoin. To reach that point in time, the airflow over the wing must travel faster than the airflow under the wing. A condition called underpressure occurs above the wing. As the air moves faster, the underpressure becomes greater. Finally, the underpressure becomes so great that it is able to lift the aircraft off the ground and into flight. To make a larger aircraft fly, you can do two things. You can make the wings larger or you can make the engines stronger. Usually, both of these things are done in combination.

With hinged sections of the wing, you can adjust the direction of the airflow. By moving these, you can make the aircraft climb or descend, or steer it left and right. Other hinged sections of the wing allow the aircraft to fly more slowly or reduce speed in the air. 

In short, the air that we breathe every day is able, with enough speed, to make something fly. Even something as heavy as a Boeing 747 has no problem lifting off. When the aircraft races down the runway at around 300 km/h (190 mph) and the pilot pulls the steering yoke towards him, first the nose wheel and then the other wheels leave the ground and the aircraft starts to fly.