The 1198th Operational Evaluation and Training Squadron was a unit at Norton Air Force Base, San Bernardino, California from 1965 to 1972 which conducted the initial testing of C-130 Hercules transports modified for special operations under the project names of Thin Slice and Heavy Chain which led to the MC-130 Combat Talons, still a key component of Air Force Special Operations Command. Its initial commander was Lt. Col. Robert Marks.