Concurrent with the first batch of Elco 70-foot PT boats (PT’s 10-19), the U.S. Navy also ordered twelve boats to be fitted out as submarine chasers, or PTC’s. These boats were the same as their torpedo-boat sisters, but the PTC’s would carry twenty-four depth charges instead of torpedoes. Six charges would be carried in racks on the stern, while four more charges could be carried in two Y-guns located forward of the stern racks. Reloads were carried on rails that ran alongside the port and starboard deck edge.
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