An airfoil structure including a plurality of molded monolithic members that extend in a side-by-side manner along the spanwise direction of the airfoil structure. Each molded monolithic member is realized from continuous material that is molded to form a corrugated portion with top and bottom flange portions extending from the corrugated portion. As a result of the molding operation, the corrugated portion is integrally formed with and structurally joined to the top and bottom flange portions. The top flange portions of the side-by-side arrangement of molded monolithic members define a portion of the top surface of the airfoil structure. The bottom flange portions of the side-by-side arrangement of molded monolithic members define a portion of the bottom surface of the airfoil section. The corrugated portions of the side-by-side arrangement of monolithic members define internal support structures (preferably closed-cell cores) extending along the spanwise direction of the airfoil structure. The side-by-side arrangement of monolithic members structurally integrates portions of the top skin and bottom skin to support structures that extend between such top and bottom surface portions. Such structural integration provides enhanced structural resistance to torsional loading of the airfoil section due to the fact that such loads are resisted by the continuous material that makes up the both top and bottom surfaces as well as the support structures extending therebetween.