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The Avro Vulcan (Top) and Boeing B-47 (bottom) were designed for similar missions, but designers took very different approaches. The British favored buried engines for reduced skin friction drag (e.g Handley Page Victor, Vickers Valiant, de Havilland Comet) and delta wing. Boeing favored podded engines on a high aspect ratio wing. This was the forerunner of all long-range commercial aircraft designs. |
Dan Raymer's book "Aircraft Design: A Conceptual Approach" is the textbook for many aircraft design capstone undergraduate courses. It covers almost all aspects of conceptual design, including initial sizing, configuration layout, aerodynamics, propulsion, stability & control, mass properties, and structures and materials. The notes appended here provide some cross-references and annotations to the 4th edition of the book. A new edition is expected in 2012.
Characteristics of the standard atmosphere are listed in Appendix B. However, a procedure for calculating the characteristics of the atmosphere at an arbitrary altitude is not described in the book. If a spreadsheet is used to simulate the mission, a knowledge of pressure, density, temperature and the speed of sound is essential for mission analysis. A description of the atmosphere up to the top of the stratosphere (about 65,600 ft), can be found here, along with an accompanying Excel spreadsheet. There are also websites where the calculations can be performed, such ashttp://www.digitaldutch.com/atmoscalc/.
Raymer's website (www.aircraftdesign.com) also contains a cornucopia of useful information, plus links to other websites.
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Typographical Errors
Every textbook has some typographical errors. Raymer's text has its share, and here are
some corrections. The fifth edition of the book should have these errors corrected.
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The annotations use the same terminology as for Raymer's text, with a few exceptions. There is one particular area where Raymer's definitions can (and do) cause some confusion with students. This area is the terminology of components of drag due to lift. Raymer defines drag due to lift and induced drag as being one and the same thing. On page 307 he states that "Drag forces that are a strong function of lift are known as induced drag or drag due to lift". However, McCormick (p.186) makes the observation that "Strictly speaking, this definition of CDi [induced drag] is not correct. Although it has become practice to charge to CDi any drag increase associated with CL, some of this increase results from the dependency of the parasite drag on the angle of attack. What, then, is a more precise definition of CDi? Very simply, the induced drag at a given CL can be defined as the drag that the wing would experience in an inviscid flow at the same CL." This is a good enough definition, ignoring for a moment the problem that a wing could experience neither lift nor drag in an inviscid flow because the Kutta condition at the trailing edge would not be met.
The annotations more closely follow the definitions in Nicolai (pp. 11-7 to 11-9), in which drag due to lift is broken down into two parts:
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