Static strength of CFRP laminates with embedded fiber-optic edge connectors

Embedded fiber-optic connector systems in aircraft composite structures have to fulfill several requirements, e.g. low optical loss, enable composite part trim, small effect on structural strength, etc. In a previous paper by the author, a manufacturing technique for embedding standard fiber-optic connection hardware in aircraft composite components was presented. The manufacturing technique enables composite part trim and entails embedded fiber-optic connections with low optical loss. In the present paper, the manufacturing technique and fiber-optic connections were evaluated with respect to their effect on the composite static strength. The results reveal that the effect of embedded fiber-optic ferrules on the composite static strength is rather large, both in tension and compression, and that the reduction in strength is mainly related to the extensive ply waviness that occurs when fiber-optic ferrules are embedded. The reduction in composite static strength was, however, smaller when larger specimen size was used and when cutouts were made to accommodate the embedded fiber-optic ferrules.