Wing

A wing is a special part that helps objects fly through the air. It works by creating lift, an upward force that lets birds, airplanes, and some insects stay in the sky. Wings also create drag, which is the resistance they feel when moving through the air. The balance between lift and drag is very important for how well a wing works.

Wings have two main features that decide how they perform. The first is called an airfoil, which is the shape of the wing when you look at it from the side. The second feature is called a planform, which is the shape of the wing when you look at it from above. Engineers and scientists measure how good a wing is by using something called the lift-to-drag ratio. This tells us how much lift we get for the amount of drag we have.

The study of how wings move through air is part of a bigger science called aerodynamics. This science helps us understand how wings can fly faster, higher, and more efficiently. Similar shapes that move through water, called foils, are used on fast boats that lift out of the water, like hydrofoil power vessels and foiling sailboats. Even submarines use special parts called diving planes to move up and down under the water, and the science behind this is part of hydrodynamics.

Etymology and usage

The word wing comes from Old Norse vængr. At first, it described the front limbs of birds and parts of buildings called aisles. Later, "wing" came to mean things that can lift, like the wings of insects, bats, pterosaurs, boomerangs, some sail boats, aircraft, and the airfoil on a race car.

Aerodynamics

Main article: Lift (force)

The design of airplane wings is important for aerodynamics. Aerodynamics studies how air moves around things. For a wing to create lift — the upward force that helps planes fly — it needs to be at the right angle to the air. When the wing is at this angle, it pushes air down, and the air pushes back up on the wing.

This upward push happens because the air pressure is lower on the top of the wing and higher on the bottom. This difference in pressure creates lift, helping the plane stay in the sky. Different ways of thinking about air movement and pressure all explain how lift works.

Design features

Aircraft wings have special shapes that help them fly. They often have a rounded front edge called the leading edge and a sharp back edge called the trailing edge. Pilots can use devices like flaps and slats to change the wing’s shape during flight for better control.

Wings also have other helpful features, such as winglets at the tips to reduce drag and ailerons near the ends to make the plane roll. Some planes even have variable-sweep wing parts that change shape for different speeds, like the F-111 Aardvark and F-14 Tomcat.

Types

Wings come in many shapes and designs for different flying needs. Some common types are swept wings, angled backwards for faster flight. Delta wings are triangular and used in fast jets and spacecraft. Variable sweep wings can change their angle while flying. Elliptical wings have a curved shape to improve efficiency. Trapezoidal wings are often found on commercial airplanes.

Applications

Besides fixed-wing aircraft, wings are used in many other ways. Hang gliders use wings that can be flexible or rigid. Kites use different lifting surfaces. Flying model airplanes rely on wing shapes. Helicopters use a special kind of wing that rotates to control movement. Propellers use blades shaped like wings to help them move through the air.

The NASA Space Shuttle used its wings to glide safely when returning to the ground, making it a type of spaceplane. Some racing cars, like Formula One cars, have special upside-down wings called airfoils that help them stay steady at high speeds. Sailboats use sails shaped like vertical wings to travel across the water.

Flexible wings

In 1948, Francis Rogallo invented a special kind of wing that could bend easily. Later, Domina Jalbert made another type of flexible wing that could catch the wind well. These flexible wings helped create new kinds of airplanes.

In nature

Wings have evolved in many animals and plants. Birds, bats, and pterosaurs developed wings from their limbs. Insect wings are a separate structure. Wings help animals move and adapt in many ways. Some birds, like penguins, are great swimmers and use their wings to glide through the water.

Examples of wings in nature include winged tree seeds that spin as they fall, the special shape of a laughing gull's wings, bats flying through the air, and dragonflies mating while flying.