News 1: How do birds fly?

The shape of a bird’s wing is important for producing lift. The increased speed over a curved, larger wing area creates a longer path of air. This means the air is moving more quickly over the top surface of the wing, reducing air pressure on the top of the wing and creating lift. Also, the angle of the wing (tilted) deflects air downwards, causing a reaction force in the opposite direction and creating lift.

Larger wings produce greater lift than smaller wings. So smaller-winged birds (and planes) need to fly faster to maintain the same lift as those with larger wings.

Wing loading tells you how fast a bird or plane must fly to be able to maintain lift: wing loading = weight/wing area (. A smaller wing loading number means the bird/plane can fly more slowly while still maintaining lift and is more maneuvrable.

If you tried the paper activity from the front of this article, you might have been surprised by what happened. In most cases a person would think the paper would go down and not lift up when they blow air across the top.

It may not be what you would expect, but it is what birds and planes do to lift off the ground and fly. Blowing faster-moving air above the sheet paper lowered the air pressure above the paper. Now the air pressure below the paper is higher and creates lift. Lift does exactly what it sounds like; it lifts objects off the ground when everything is just right.

How Do You Make Air Move Faster?

We blew air over the top of the sheet of paper to create the lower pressure. You cannot do that for birds and planes. Instead, the wing of both birds and planes are shaped so that air passing over the top has to travel a longer distance and so it has to speed up as it goes over the top of the wing. This creates the difference in pressure above and below the wing.

How Do You Get the Air to Move Over a Wing?

Getting the air to move over and under the wing also requires the wing to be moving. This is called thrust. Thrust is created when birds flap their wings using their strong breast muscles. Planes use another method for thrust. They use engines. These can be either propeller or jet engines. With both birds and planes, thrust is the other part of creating lift and the ability to fly. So the shape of the wing and the ability to move it through the air are the two things needed for bird and plane flight.