Abstract: A winch drum including a barrel portion having composite flanges secured at each end. The flanges including two or more partially independent, segmented, modules with each modular section placed diametrically one on the other thus forming an expanding concentric flange. The first modular section secured to the winch drum, barrel portion having a relatively small outside diameter with respect to the barrel is treated, from a design standpoint, as the primary shear module. The second and subsequent concentric sections are only secured to the lower modular section at their outer faces and treated independently for shear and bending with each cross section being sized to accommodate the forces applicable only to that modular section thus reducing shear and bending in these modules.