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Wing Design There are essentially two parts to wing design: airfoil design and planform design. In designing both of these sections, all three dimensions of the wing will have been accounted for. 
Planform Design A birds eye view of the wings is known as the planform. The distance from one wing-tip to another is the span. Span is one of the first measurements that are determined. A longer span would directly reduce the induced drag. However, making the span too long puts too much stress on the fuselage, and increases the structural weight. Finding an optimum span does not only involve the analysis of span and weight, but these are the two main factors. If the span width were divided by the chord of the same wing, the resulting number is the aspect ratio. On a flight of a relatively slow velocity, a higher aspect ratio means more efficiency. 
What is an Airfoil? Well, if you've been reading some of the other pages on AeroNet, chances are you've probably have seen this word many times by now. An airfoil describes the teardrop like shape of a wing. Some parts of the tail assembly are airfoils as well. In most cases, airfoils are asymmetric, but some types of planes have symmetrical airfoils. Geometry of an Airfoil Figure 3.1.3 displays the various measurements of an airfoil that are important in defining how it will behave in a flow of air. As you can see, the chord is the straight line starting from the leading edge ending at the trailing edge. The mean camber line is a plot of the median distances from the top of an airfoil to the bottom. Finally the camber is the largest length from the chord to the mean camber line. This camber is a measure of the thickness of the wing. 
The camber usually depends on what type of flight an airplane will have to make. Generally, thinner cambers are used for high-speed planes, and thicker cambers for relatively slower larger planes that need more lift. Wing Area In addition to developing a suitable aspect ratio, engineers have to calculate an optimum wing area. Just like the camber in an airfoil, wing area influences the amount of lift produced. A larger wing area will produce more lift, however, it will also experience more induced drag as well as friction drag. Finding a well balanced medium within these main parameters is the main job in designing wing area. Designing a wing is no easy job. There are multitudes of factors to consider, all influencing one another. Making an improvement somewhere on the wing, generally requires a sacrifice of another type of performance. The fact that some planes are designed to fly faster or slower helps in deciding what to sacrifice. 
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