ASEC was tasked to validate the existing capacities of a series of 345kV and 138kV H/A-Frames by the client. Utilizing historical documentation from a major tubular steel fabricator, ASEC modeled the structures in PLS-POLE to determine the structure capacities, as well as developed the structural loading based on the existing configurations. This effort was required to validate the original design intent and report on any deficiencies with current Client Standards. Additionally, a full evaluation of main member utilization, under original loading combinations and updated extreme event combinations, was performed. Lastly, a detailed analysis of all connection capacities under the original design conditions was performed utilizing Math CAD hand calculations.