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Unit 1 How did aeronautics begin
Aeronautics is typically defined as the art or science of flight, or the science of operating aircraft. This includes a branch of aeronautics called aerodynamics. Aerodynamics deals with the motion of air and the way it interacts with objects in motion, such as an aircraft. Both of these branches are a part of the tree of physical science. Aviation, however, refers to the operation of heavier-than-air craft. The theoretical basis for these branches stems from the work of Sir Isaac Newton in the 1600s. Newton developed laws that defined the effects of forces acting on objects in motion or at rest. He also developed the concept of viscosity, or fluid friction, which is the resistance of air or any other fluid to flow. Daniel Bernoulli, in the 1700s, developed the principle that the speed of a fluid is directly related to pressure. That is, the faster the flow of a fluid, the lower the pressure that is exerted on the surface it is flowing over. For example, if air is flowing faster over the top of a surface than under a surface, the pressure on the top of the surface will be less than that underneath. Understanding of these concepts was necessary to the development of flight. Without understanding the aerodynamic principles of flight, humans would simply be mimicking the actions of birds. It was demonstrated through many spectacular yet often disastrous attempts that pure imitation would not enable humans to fly. How did aeronautics evolve past the imitation of birds? The science of aeronautics really began to evolve in the late 18th and early 19th centuries. Philosophers and early scientists began to look closely at physical phenomena such as gravity and motion. As paths of communication were established between distant cultures, the understanding of flight began to coalesce. With their wealth of understanding of kites, rockets and fireworks, the Asian cultures defined and harnessed propulsion. The Europeans with their penchant for analysis, definition and precision, began to piece together the concept of force. This growth in knowledge and communication continued throughout the 19th century. By the very late 19th and early 20th centuries, this knowledge had evolved to the point where people sought to put it to practical use. As space is the frontier of today, flight was a frontier of that time. Along with factual knowledge, the method of discovery as well as trial and error evolved into the scientific method. The scientific method became a widely accepted process to question, analyze, test and verify results. Concepts and ideas that were subjected to the scientific method received general acceptance and were used as bases for generating new ideas. The classification and definition of forces involved with flight were developed. We know them today as lift, drag, weight and thrust. Scientists began to understand how they worked together to enable an object heavier than air to fly. Once these concepts were well understood, it was only a matter of time before humans figured out how to not only fly, but to control their flight. Balloons, which by this time were old news, enabled people to fly but aeronauts remained at the mercy of the wind to determine where they went. With the invention of the airplane people could fly when, how and where they wanted. Another frontier had been conquered. Within a few short years, airplane designers refined the shape of wings and overall construction to improve airplane performance and safety. Further improvements in airplane design allowed flight to become accessible to everyone.
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