Senior Airman Eric Medina, 92nd Air Refueling Squadron boom operator, explains how a KC-135 Stratotanker works to Central Washington University Air Force ROTC students during a base wide tour April 17, 2015, at Fairchild Air Force Base, Wash. The tour included stops at the base headquarters for a mission briefing, the Aquatics Center for a water survival demonstration, a KC-135 Stratotanker static display, aerospace physiology demonstrations, military working dog demonstration and Survival, Evasion, Resistance and Escape School for a UH-1N Iroquois helicopter static display and shelter, signal and fire demonstration. (U.S. Air Force photo/Senior Airman Janelle Patiño)