Background:
At any given moment, roughly 5,000 airplanes crisscross the skies above the United States alone, amounting to an estimated 64 million commercial and private takeoffs every year (source: NATCA). Considering the rest of the world 's flight activity, the grand total is almost incalculable. In order to understand how airplanes fly, we must break down the parts of an airplane and understand the physics behind the airplanes most important components: the engine/propeller, and the wings.
In the earlier days, airplanes gained thrust only by a single propeller. Nowadays huge turbofans are attached to the wings or the tail of the aircraft instead. Of course propelled airplanes are still used, most modern planes have jet engines.
I will be going over the physics of propellers, and how airplanes gain lift. Lastly, I will go over the details and aspects of jet turbofans used on commercial airlines.
A propellers main function is to push the plane forward through the air. Hence it needs all the air that it can get. Since air becomes scarcer as we go higher, this is why most propelled airplanes do not travel at high altitudes like most jumbo airliners do, because these airplanes are able to fly only where there is the greatest amount of air; and that is nearer the earth’s surface. The physics behind propellers interestingly relates to Newton’s 3rd law. Newton’s 3rd law states “For every action, there is an equal and opposite reaction.” Propellers are an application to this law because as the propeller spins, it sucks in air and pushes it out the back of the plane. This is the action, and reaction is the forward motion of the plane (source: dynamic science website). The more air pushed back, the more the plane is pushed forward. The way my model airplane’s propeller works is from winding a rubber band. This model not only exhibits Newton’s 3rd law but also is an application of conservation of energy. It is an application of
Cited: Sanders. "AERODYNAMICS AND THEORY OF FLIGHT." Aerodynamics and Theory of Flight Langley Flying School. N.p., May 2008. Web. 19 Mar. 2013. Terry, John. "Flight-propeller-How It Works." Flight-propeller-How It Works. N.p., Oct. 2001. Web. 19 Mar. 2013. "The Physics of Airplane Flight." Mini Physics. N.p., 2007. Web. 19 Mar. 2013. "The Physics of Flight (Newton and Bernoulli)." The Physics of Flight (Newton and Bernoulli). N.p., n.d. Web. 19 Mar. 2013.