From left, U.S. Air Force Senior Airman Randall Brown and Airman 1st Class Ryan Mundt, 633rd Civil Engineer Squadron engineering technicians, prepare for an optical site survey at Joint Base Langley-Eustis, Va., March 9, 2017. Brown and Mundt are members of the mapping section, which keeps track of all on-base facilities and floor plans, as well as records of all renovations and floor plans of demolished buildings. (U.S. Air Force photo/Senior Airman Areca T. Bell)