 During the winter of 1942–43, some of these destroyers were organized into Western Support Force (WSF) groupings of three ships to augment protection of convoys coming under attack in the western Atlantic.The WLEF was theoretically organized into eight escort groups able to provide an escort of four to six ships to each convoy.WLEF escort group assignments were more dynamic than the MOEF escort groups, and WLEF escorts seldom worked with the same team of ships through successive convoys.