Taper ratio (English spelling)

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[Names of each plane part]
The length of a wing's planform from side to side is called the wing span, the length from front to back is called the chord length, and the area of ​​the planform is called the wing area (Figure 8). The chord length changes along the wing span except for rectangular wings, and the ratio of (chord length at the wing tip) to (chord length at the wing root) is called the taper ratio. The wing area usually includes the part where the fuselage overlaps the wing, because this part also generates considerable lift due to the influence of the airflow from both sides.

*Some of the terminology explanations that mention "taper ratio" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

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［平面形各部の名称］
　翼の平面形において左右の長さを翼幅wing span，前後方向の長さを翼弦長chord length，平面形の面積を翼面積wing areaという(図8)。翼弦長は矩形翼(長方形の翼)以外では翼幅に沿って変化し，(翼端翼弦長)/(付け根翼弦長)をテーパー比taper ratioという。翼面積には翼に胴体が重なる部分も含めるのがふつうで，これはこの部分も左右の気流の影響でかなりの揚力を出すからである。…

※「taper ratio」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報