Analytical Geometry in Common Layouts: II. Folding Wings Employing a Skew Hinge Axis Available to Purchase

FOLDING wings of the type employing a skew—hinge axis present a somewhat difficult lay‐out problem in way of the wing cut. The problem with which this article is concerned is that of obtaining, in the form of vertical spanwise sections, the surface swept out by one cut edge of the folding portion as the wing rotates. This enables the bottom cut line to be determined when the top cut line is known, or vice versa. If the leading edge rises when the wing folds, the top cut line will be determined by the fully folded position; if the leading edge falls, it will be the bottom cut line that is thus determined. The following diagrams and calculations are made for the rising leading edge type; the same method may be applied to the falling leading edge type viewing the wing upside down. A numerical example is worked along with the theory.