AIRFOIL AND WING GEOMETRY Module 4 of Conceptual Aircraft Design: an interactive module for third-year aerospace engineering ========================================================================= WHAT IT IS Eight short, interactive lessons on choosing an aircraft's airfoil and wing geometry, following Raymer, Aircraft Design: A Conceptual Approach, Chapter 4, with the tail volume coefficients of Chapter 6: airfoil geometry and the NACA families; thin-airfoil theory, Reynolds number and stall; the design lift coefficient and the thickness a Mach number allows; aspect ratio; sweep; taper and the planform with its mean aerodynamic chord; twist, incidence, dihedral and wing position; and the tails. The business jet sized in Module 3 gets its wing and tails step by step through the whole module. The lessons have interactive figures, worked examples and questions with instant feedback. There is also a Practice Lab, a Self-Check Quiz, a printable worksheet, the Wing Planform Designer, a formula sheet and a glossary. Everything runs in your web browser from this folder. No internet connection, installation or account is needed. HOW TO OPEN 1. Unzip (extract) the download first. Windows: right-click the .zip file > Extract All... > Extract. macOS: double-click the .zip file. An unzipped folder appears next to it. 2. Open the unzipped folder and double-click index.html. The module opens in your default web browser. 3. Start with Lesson 1, or use "Continue where you left off" on the home page when you come back. Do not open the files from inside the zip preview (for example by double-clicking into the zip in File Explorer without extracting it). From there the pages cannot load their figures and styles, and your progress is not saved. Keep the folder structure as it is. BROWSER SUPPORT Current versions of Google Chrome, Microsoft Edge, Mozilla Firefox and Apple Safari. JavaScript must be on (it is by default). A laptop or desktop screen works best; the pages also fit tablets and phones. TROUBLESHOOTING Pages have no styling or figures are missing A box at the top of the page says so too. Either you are viewing the files inside the zip (unzip first, see HOW TO OPEN, and open index.html from the unzipped folder), or your browser is not allowed to read the module's files. Browsers from the Mac App Store, such as DuckDuckGo, may only be allowed to open the one file you double-clicked, not the assets folder next to it. Right-click index.html, choose Open With, and pick Google Chrome, Microsoft Edge, Firefox or Safari. Progress (lesson ticks, completed questions) is not saved Progress is stored by your browser, on this computer only. It is not kept in a private or incognito window, and it is lost if you clear browsing data or if your browser blocks cookies and site data for local files. Use a normal window, allow site data, and always open the module from the same folder in the same browser. The math shows raw code such as \( C_L \), or there is no menu JavaScript is turned off. Turn it on in your browser settings, then reload the page. The CSV download in the Wing Planform Designer does nothing Some browsers block downloads from local files. Allow downloads for the page when the browser asks, or try another browser. Printing Use your browser's Print command (Ctrl+P, or Cmd+P on a Mac) and choose "Save as PDF" to keep a copy. The Formula Sheet, the Printable Worksheet and the quiz results are designed for printing. FOLDER OVERVIEW index.html Start here: the module home page README.txt This file lessons/ Lessons 1-8 practice/ Practice Lab, Self-Check Quiz, Printable Worksheet tools/ Wing Planform Designer reference/ Formula Sheet and Glossary assets/ Styles, scripts, the aircraft data (assets/js/aero.js), the airfoil, planform and statistics library (assets/js/wing.js) and the bundled math library (never edit assets/vendor) DATA The aspect-ratio statistics, dihedral guidelines, tail aspect and taper ratios and tail volume coefficients are after Raymer (Tables 4.1 to 4.3 and 6.4); check them against the edition you use. The NACA four-digit equations are from NACA Report 460 (1933). The comparison aircraft are from L. K. Loftin, Quest for Performance, NASA SP-468 (1985), as in Module 1. The business jet comes from Module 3; the other example aircraft are illustrative designs, not real types. CREDITS AND LICENSES This module bundles one open-source library under the MIT License. Its full license text is in assets/vendor. KaTeX 0.18.9 (math typesetting) Copyright (c) 2013-2020 Khan Academy and other contributors License: MIT, see assets/vendor/katex/LICENSE.txt The page framework (assets/js/cyl-*.js) is shared with the dynamics modules (Cylindrical Coordinates, Curvilinear Motion, Mass Moments of Inertia, Angular Momentum).