Civil engineer squadron
PETERSON AIR FORCE BASE, Colo. -- Airman 1st Class Jerry Harrison, 21st Civil Engineer Squadron electrical systems journeyman, tests the incoming wire to a street lamp Jan. 4, 2012, at a parking lot east of the softball fields. The 21st CES operates and sustains essential facilities and utility infrastructure systems on base, responding to myriad work orders daily including maintaining roads, generators, and water and electrical lines. (U.S. Air Force photo/Senior Airman Jacob Morgan)