On Replacing an Ellipse with an Oval in Aircraft Design Elements
Authors: Kaverin V.A., Shchukin D.A., Morozov E.E., Taratonkina V.S.
Published in issue: #8(176)/2026
Category: Aviation and Rocket-Space Engineering | Chapter: Design, Construction, Production, Testing, and Operation of Aircraft
Aircraft structures employ elliptical profile elements are used, for example, nose parts and dropable nose fairings in the form of rotation shells with elliptical outer contours. Examples of such constructions are given and a method for replacing an ellipse with an oval with an exact approximation of the oval profile to the ellipse profile is considered. An oval is of interest to designers and technologists as a simpler shape than an ellipse, consisting of arcs of large-radius circles conjugated with arcs of small-radius circles. The method of replacing an ellipse with an oval is based on using the oval equation derived by the authors, as well as using the values of the maximum or minimum radius of curvature of the original ellipse as one of the radius of the oval, followed by calculating its second radius from the oval equation. Replacing an ellipse with an oval simplifies the design and manufacturing technology of aircraft hulls and functional components, including structural elements that extend to the outer contours.
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