The 25th Space Range Squadron (25 SRS) is a non-flying squadron of the United States Air Force. It is assigned to the 595th Space Group, Air Force Space Command, Schriever Air Force Base, Colorado. The 25 SRS operates the Space Test and Training Range (STTR).The 25 SRS is one of the oldest units in the United States Air Force, first being organized as the 25th Aero Squadron on 13 June 1917 at Kelly Field, Texas.