Radar picket escort ships, based in Guam or Pearl Harbor, provided long-term presence at sea offshore to guard against trawler infiltration. Originally built for WWII convoy duty, and then modified for distant early warning ("DEW") duty in the North Atlantic, their sea keeping capability made them ideal for long-term presence offshore where they provided support for SWIFT boats, pilot rescue and sampan inspection. There were two or three on station at all times. Deployments were seven-months duration, with a four- or five-month turn-around in Pearl. When off station, they alternated duty as Taiwan Defense Patrol, with stops in Subic and Sasebo for refit mid-deployment.