Take Flight: How & Why Airplanes Are Built A Certain Way!
Updated: Aug 2
Flying in an airplane can be a unique experience, but have you ever wondered just how airplanes fly? Is it solely based on gravity, the sky, or is it a special magic?
If you have ever seen an airplane, you will first notice that most airplanes have the same basic shape. Why is that? The shape of an airplane is what makes it the most effective for flying. Before we dive into how this works, we must first learn the concept of aerodynamics and the four forces of flight.
Aerodynamics can be defined as the study of the properties of moving air and the interaction between the air and the solid bodies moving through it. Sounds complicated, doesn’t it? In simpler terms, aerodynamics is the way air moves around things!
Not only do the rules of aerodynamics explain how an airplane is able to fly, but anything that moves through the air reacts to aerodynamics. For example, someone jumping on a trampoline is moving through the air as their feet launch off the trampoline platform. Another example would be a rocket blasting off the launch pad, or a kite soaring through the sky.
In fact, aerodynamics even acts on cars, since air flows around cars when they are in motion!
Aerodynamics are essential to understand how airplanes fly, but there is also another key element to it, which are known to be the four forces of flight. The four forces of flight affect anything that fly, including airplanes! These four forces are weight, lift, thrust and drag. These forces affect the movement of an object, such as moving up or down, and even speed, such as going faster or slower.
Let's start with weight. Everything on planet Earth has weight, as this force comes from gravity pulling down on objects. In order for an airplane to fly, it must have a force that pushes it in the opposite direction from gravity, or upwards. Airplanes are built so that their weight is balanced, as its spread from the front of the plane to the back of the plane.
The bigger the weight, the more force upwards it will need. This is where the force of lift comes into play!
Lift is simply the push that allows an object or something to move upwards. It is the exact opposite force of weight. In order for something, including an airplane, to fly, it must have lift. In addition, for an airplane to move upwards, its lift must exceed the force of weight.
For instance, a helicopter’s rotor blades at the top of a helicopter is what allows it to give lift, as this force exceeds its force of weight pushing downwards on it.
You may be wondering where this “push” or lift comes from on an airplane. Of course, each airplane has rotors that contribute to its lift, but the true force of lift for an airplane is provided thanks to the shape of the wings on an airplane.
Airplane wings are found on the sides of an airplane, and are the sole reason as to how airplanes can fly. Airplanes’ wings are curved on top, and are flatter on the bottom. This shaping makes the air flow over the top faster than under the bottom, so less air pressure is on top of the wings. This specific condition, in appliance to general aerodynamics, makes the wing and the airplane body attached to it, move upwards. In sum, the way air moves around the wings gives the airplane lift which allows it to take air and fly!
Of course, there will always be a component with moving objects that try to slow it down, which is known as drag. Drag is essentially what makes it hard for an object to move. For example, it is hard to move in water than it is in air. Why? Water causes more drag, or resistance, than air. The shape of an object changes the amount of drag. It is proven that most round surfaces have less drag than flatter surfaces.
Newton’s laws of motion states, “for every action, there must be an equal and opposite reaction”.
This “equal and opposite” reaction to drag is known as thrust. Thrust is defined as the push that moves something forward. For an airplane to keep moving forward, it must have more thrust than drag. A small airplane, for instance, will get its thrust from a propeller. On the other hand, a larger airplane gets its thrust from jet engines.
The body of the airplane, or fuselage, is shaped like a tube, with its rounded front nose. This tube-like build makes the airplane, aerodynamic, which reduces the effect of drag. The wings located on both sides of the plane are spread out with rounded tops, generating as much lift as possible which helps the plane to stay in the air.
Overall, the shape of an airplane is designed to maximize the forces of lift and thrust, while minimizing the effects of drag. In summary, an airplane can fly when all four forces of flight are working together, but this is not possible without the specific shape and design of airplanes!
Next time you are jumping on a trampoline, think about how aerodynamics are effecting how high you go!