An airfoil structure is presented. The airfoil structure includes an outer casing substantially surrounding a composite core. The composite core includes a plurality of fiber bands, each of the plurality of fiber bands is placed at a predetermined position and orientation at a time, wherein the plurality of fiber bands are interwoven in an in-plane and out-of-plane orientation by interleaving each of the plurality of fiber bands placed in a plane with one or more of the plurality of fiber bands of an adjacent plane to define an interleaved structure. A method for manufacturing an airfoil structure including the composite core is also presented.