There are a lot of factors that act upon the airplane, all of which work in tandem to allow an airplane to fly.
It is hard to imagine that a century ago, it would have been impossible to fly. However, today there are hundreds of thousands of flights in the air this very minute. The credit for this goes to the Wright Brothers, who were responsible for the first successful flight. Still, a question to ask is ‘how do airplanes fly?’
The primary source of power for an airplane is jet engines. These engines are much more powerful than regular engines; they are also far noisier. These engines are powered by fuel, just like most regular engines, which is why it is quite common for planes to land for refueling especially on long trips.
However, in addition to engines, there are a variety of factors that play into flight. In fact, there are things that can fly without an engine. Imagine a paper airplane; it does not have an engine, yet it has the ability to fly across a room. Still, they can’t fly for long, and sometimes not even the length of the room. This is because of wind currents. The paper airplane lifts off on air currents using the force that the person flying the paper plane provides. Similarly, the airplane takes of using the jet engines, which provide the force, and then glides on air currents.
There are a total of four forces that act upon the airplane. These are the weight, lift, thrust, and drag. Weight and lift work against each other, as do thrust and drag. The thrust is the power that is provided by the jet engine, while the weight of the plane and the people on it pull the plane down. In addition, there are the winds that act upon the plane. The winds are responsible for both lift and drag.
As discussed, air currents allow the plane to lift off. However, in addition, these wind currents also push back on the plane, providing resistance for the plane. Hence, the lift and drag must cancel each other out at the least. In this, the wings of the plane play a great part; they are designed in such a way which maximizes lift while minimizing drag. Their shape is called an airfoil or aerofoil. It is curved downward on the top, and flat on the bottom. This allows the wings to cut through the wind by splitting it into two streams which flow over and under the wings. The curved top of the wing slows down the wind, while the bottom half leaves it the same. This mismatched speed is what creates lift.
In ideal circumstances, the lift and thrust, should be more than the drag and weight, which is what allows airplanes to fly.
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