In August 1960 the unit became one of the first to transition to the F-102A Delta Dagger Mach-2 all-weather interceptor and began a 24-hour alert to guard the Texas Gulf coast. On 1 January 1970, the squadron was re-designated as the 111th Combat Crew Training Squadron and served as the Air National Guard's RTU (Replacement Training Unit) for the TF/F-102A. In 1971, when the active-duty force ceased F-102A training and closed Perrin AFB, Texas on 30 June 1971, the Houston-based 111th FIS became the Replacement Training Unit (RTU) for all Air Defense Command F-102 pilots, and the squadron received several TF-102A dual-seat trainers which were transferred from Perrin AFB while also retaining the T-33A instrument training function.