Title: Case Study of Core-Stiffened Wing Versus Skin-Stringer Approach for Intermediate-Size Flight Structures

Authors: Jeffrey M. Perkins, Richard K. Dropek

DOI: 10.33599/nasampe/c.22.0170

Abstract: Advanced Air Mobility (AAM) companies aim to produce a new style of aircraft, with new materials at a pace and scale that has not yet been accomplished in the composites aerospace industry. Many material options and manufacturing processes exist for prospective manufacturers who are looking to optimize the performance and minimize the weight of composite structures. Vehicle weight, manufacturing efficiency, and FAA certification are a few of the top considerations for AAM designers. This paper presents the results of an engineering study conducted to compare two different approaches for representative AAM vehicle primary structures. Equivalent core-stiffened and skin-stringer wing designs were developed for a typical mid-size (~12-meter) aircraft structure. The composite design, along with the tooling and equipment required for manufacturing, were evaluated for the wing skin and spar. Equivalency comparisons were made for buckling, overall strength, structural deflections, and weight using typical loading scenarios. The composite study showed that the skin-stringer designs may have equivalent or improved performance when compared to the core-stiffened wing designs. The stringer and intercostal designs act as a gateway allowing for the closed mold Same Qualified Resin Transfer Molding (SQRTM) prepreg manufacturing approach to provide FAA certifiable structures with improved quality and repeatability. This may also accelerate FAA certification while simultaneously enabling a transition to out-of-autoclave (OOA) processing.

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Conference: CAMX 2022

Publication Date: 2022/10/17

SKU: TP22-0000000170

Pages: 18

Price: $36.00