Wing

A wing is a special kind of structure that helps objects fly through the air. It works by creating lift, which is the upward force that lets birds, airplanes, and even some insects stay in the sky. At the same time, wings also create drag, which is the resistance they feel from 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. For a long time, it mainly described the front limbs of birds, as well as parts of buildings called aisles. Over time, the meaning of "wing" grew to include things that can produce lift, such as the wings of insects, bats, pterosaurs, boomerangs, some sail boats, aircraft, and even the airfoil on a race car.

Aerodynamics

Main article: Lift (force)

The design of airplane wings is a key part of aerodynamics, which studies how air moves around objects. For a wing to create lift — the upward force that helps planes fly — it needs to be at the right angle to the airflow. 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 pressure difference creates lift, helping the plane stay in the sky. Different ways of thinking about air movement and pressure all explain how lift works, even though they look at it from different angles.

Design features

Aircraft wings have special shapes and parts 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 different shapes and designs, each suited for specific flying needs. Some common types include swept wings, which are angled backwards to help aircraft fly faster, and delta wings, which are triangular and often used in fast jets and spacecraft. Other types include variable sweep wings, which can change their angle during flight, and elliptical wings, which have a curved shape that helps improve efficiency. Trapezoidal wings are another common design, often seen in commercial airplanes.

Applications

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

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

Flexible wings

In 1948, Francis Rogallo invented a special kind of wing that was very flexible. Later, Domina Jalbert created another type of flexible wing that could catch the wind well. These flexible wings were important for developing new kinds of aircraft.

In nature

Wings have evolved many times in different animals and plants. Birds, bats, and pterosaurs developed wings from their limbs, while insect wings formed as a separate structure. Wings help animals move, spread out, and adapt in many ways. Some birds, like penguins, are great swimmers and use their wings to help them 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.