Airfield Systems
Senior Airman Sida Avila, 92nd Operation Support Squadron airfield systems, measures far field phasing of the glide slope to ensure proper descent angle for landing aircraft Sept. 10, 2015, at Fairchild Air Force Base, Wash. The glide slope is part of the Instrumental Landing System, which is an internationally normalized system for navigation of aircrafts upon the final approach for landing and provides guidance necessary for an accurate landing. (U.S. Air Force photo/Airman 1st Class Taylor Bourgeous)