A fourth Predator drone will be launched over Arizona border skies this week, meaning the entire Southwest border from California to Texas will now be patrolled from above. Previously, drones were not approved by the Federal Aviation Administration for use in a stretch of West Texas. Two more unmanned vehicles will be added shortly, bringing to six the number used on the Southwest border. The fleet is anticipated to reach six by year's end, controlled by Customs and Border Protection in Corpus Christi, Texas.