Title: OOA Processing Using Same Qualified Resin Transfer Molding for Electric Aviation

Authors: Chad M. Frazer, Dimitrije Milovich

DOI: 10.33599/nasampe/c.22.0169

Abstract: Increased composites use in the aerospace industry has led to lighter weight and lower maintenance aircraft. Additional reduction in weight remains a goal, especially for the growing Electric Aviation market where battery energy density is limited. Applications for passenger or cargo missions include General Aviation, Regional Air Mobility, eSTOL and eVTOL. Further goals include improved laminate quality, reduced manufacturing costs and cycle times, as well as expedient FAA and other regulatory certification. Same Qualified Resin Transfer Molding (SQRTM) is a unique out of autoclave (OoA) manufacturing process with a relatively clear path to certification since SQRTM uses prepreg material in a closed mold to produce a net-shape composite structure. Demonstrating equivalency to existing databases such as NCAMP can ease the path to certification, compared to other OOA processes, since SQRTM has been certified for commercial aerospace structures. In the SQRTM process, prepreg is laid up and compacted per typical, established best practices. The preform is assembled into an SQRTM tool or mold. The tool is heated, resin pressure within the preform is increased to 80-100psi (5.5-7bar), and the tool continues to the cure temperature. This paper will address how SQRTM can offer opportunities for the Electric Aviation market. Design opportunities will be presented along with potential improvements in laminate quality provided by SQRTM. Approaches to reduce recurring costs and manufacturing cycle times will be included, as well as examples of current SQRTM aircraft structures that are certified for commercial and military use.

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Conference: CAMX 2022

Publication Date: 2022/10/17

SKU: TP22-0000000169

Pages: 11

Price: $22.00