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Solids |
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Flight Mechanics |
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Manufacturing |
For over a century, aerospace engineers have led the progress of human technology, and brought the world closer together. Most simply, aerospace engineering is the realization of grand dreams through careful scientific thinking and planning, bold but informed innovation, and dedicated pursuit of perfection. It is the broadest of engineering disciplines, because it takes the best of all human knowledge to design, build, sell and operate a new (and always better!) aircraft or spacecraft, and to use it to the best advantage. Many aerospace projects appear so "far-out" that most people dismiss them as impossible, until they actually see them working: it is up to the AE to figure out these dreams, and reduce them to simple, step-by-step designs which are clean, simple, safe, cheap and reliable, so commonplace that anyone can use them and feel at home.
Click here to scare yourself thinking about the simple process of flying home for Christmas
So don't be surprised when you read that you can learn to design an airliner, starting out with a high-school background. The approach we take in this course is called the "Runway across Canyons".
The various disciplines of aerospace engineering, such as aerodynamics, propulsion, etc. are like mountain ranges. Sometimes we feel like we have to climb down into a canyon and then up a steep wall to get to another discipline, i.e., to really understand all the things that people have figured out over the years. In this course, we lay out a "runway", bridging these canyons, so that we can go at high speed from aerodynamics to propulsion to flight mechanics, etc., on our way to developing our own conceptual design for an aircraft. We do have a few resources, shown on the control panel of our craft, as we start the takeoff roll...
In this course we will use the motivation of designing a specific vehicle to learn about the various areas of aerospace engineering. So we will go off into one area after another, but always come back at the end of that detour, and do some more calculations or refinement of our design. All that you need is a notebook and pencil, a calculator for elementary calculations, and a spreadsheet.
Likewise, today's designs look extremely sophisticated to us. They can fly over 100 times as fast as the Wright Flyer, and go right out into Space, circle the earth every hour or so, and return to precise touchdowns on earth. Have we reached the limits of aerospace engineering? Many people, even in the 1920s, thought that airplanes had reached the limits of speed and altitude, and had detailed theories proving that not much more could be gained by investing in thought or development of these wierd machines. And today, still, we are just beginning. We have only about 100 years of powered flight experience, whereas the birds and insects that we see have evolved through maybe a million years of experience. We can't yet match them for control precision, landing versatility, payload fraction, engine weight fraction, fuel costs, maneuverability, reconfigurable geometry, or structure weight fraction. Our machines are fragile and clumsy: if their engines quit or a piece breaks off, they fall down quickly or even catch fire. They have stiff, rigid wings that can't flap, twist, fold or thrust to any significant degree. They need long runways and complex traffic control systems. You have to drive through 2 hours of downtown traffic and spend an hour and a half at the airport and another 30 minutes on the taxiway to make a flight of 200 miles. When we launch spacecraft, only about 30% of the structure and 10% of the total launch mass ever reaches orbit: the rest is wasted.
Next Section:
Today's Dreams, and their technical requirements.
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to the other topics in the course.