SOSI recently completed construction of a large test pad at their primary manufacturing facility in Sultan, WA. This flush ground level concrete pad measures 40’ x 20’ x 2’ thick, weighs approximately 240,000 pounds, and contains embedded steel I-beams used to secure the winches and handling systems to the pad. It was built to allow SOSI to test medium and large line pull winches, launch and recovery systems, and other handling equipment requiring test loads to 60,000 lbs. It can also be used with SOSI’s spooling equipment to spool new working cables and lines onto winches under tension. Almost immediately upon completion, the test pad was used to conduct Factory Acceptance Tests of a Heavy Lift Winch and a Medium Lift Winch custom designed and built for Oregon State University and the University of Washington respectively. Both winches were delivered and installed aboard the R/V Thomas G. Thompson where they were used to successfully deploy complicated two legged moorings as part of the OOI cabled observatory off the Washington and Oregon coasts.