Theory of Flight
The subject is Aerodynamics or Theory of Flight.
The word Aerodynamics comes from two root words, aeros and dynamic. Aeros simply means air while dynamic means motion. Therefore the study of aerodynamics is the study of air in motion. By the way, there is another subject called aerostatics, which is the study of air that is not in motion (static meaning: not in motion.) Aerostatics explains things like hot-air balloons and dirigibles.
For my YouTube video series I chose the title "Theory of Flight" because I wanted to emphasize two distinct but important topics. Of course one of those topics is flight. I am fist and last a pilot. I love aeroplanes (that's airplane for any americans reading this.) Like all pilots I love to fly, and like many I like to think about how we defy gravity and float above the rest of humanity dancing with the clouds.
But, I also wanted to emphasize the meaning of the word theory, as it is used by scientists. In between flights I fancy myself a philosopher and one of the particular aspects of philosophy that gets me excited is epistemology, which is the study of how we (humans that is) know things. For most people in everyday life to "know something" is just to be certain of it. That is to say to really, really, really believe it. But to a philosopher that is not enough. After all, people were certain for millennia that the sun moved across the sky each day. A mere 450 years ago, in the middle of the 16th century, a guy called Copernicus suggested that this was an illusion. The sun isn't really moving across the sky, he said. The sky is moving across the sun. He was so "crazy" that he actually believed the earth was rotating on an axis. The belief that the earth rotates was a theory when Copernicus suggested it, and it is still a theory today. The only difference is that today people don't laugh at it, they mostly believe it to be true. But why? How did science, which did not exist in the 16th century, come about and eventually convince us all to believe that the earth is rotating and consequently the sun is not actually moving across the sky.
if you were transported back in time to the 16th century do you think you could convince the people from that time that the earth is rotating?
In this video I discuss what a theory is and how the power of logic is used in science to invalidate theories that are not true. I then give an example of a common theory that many pilots believe, namely that an airplane rolls because one wing produces more lift that the other. This is a false theory, easily disproved with a simple logical analysis, and yet it persists.