3.3.1: Geometry and nomenclature
- Page ID
- 78107
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Figure 3.20: Wing geometry
In order to characterize the geometry and nomenclature of a typical commercial aircraft wing, the following wing elements are illustrated in Figure 3.20:
- Wingspan \(b\).
- Chords: root chord \(c_r\) and tip chord \(c_t\).
- Leading and trailing edges, and the line corresponding to the locus of \(c/4\) points.
- \(c/4\) swept \(\wedge_{c/4}\).
The area enclosed into the leading and trailing edge and the marginal borders (the section with \(c_r\)) view in a plant-form is referred to as wet wing surface \(S_w\). The quotient between the wet wing surface and the wingspan is referred to as the geometric mean chord \(\bar{c}\). which represents the mean chord that a rectangular wing with the same \(b\) and \(S_w\) would have.
The enlargement, \(A\), is defined as:
\[A = \dfrac{b}{\bar{c}} = \dfrac{b^2}{S_w}.\]
There is also a parameter measuring the narrowing of the wing: \(\lambda = c_t / c_r\).